dt-bindings: leds: Add cznic,turris1x-leds.yaml binding

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

Signed-off-by Pali Rohár <[email protected]>

---
 .../testing/sysfs-class-led-driver-turris1x   |  23 +
 drivers/leds/Kconfig                          |   9 +
 drivers/leds/Makefile                         |   1 +
 drivers/leds/leds-turris-1x.c                 | 412 ++++++++++++++++++
 4 files changed, 445 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-class-led-driver-turris1x
 create mode 100644 drivers/leds/leds-turris-1x.c

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +11 -0

new file mode 100644
index 000000000000..02be9197554d
@@ -0,0 +1,23 @@
+What:		/sys/class/leds/<led>/device/brightness
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) On the back size of the Turris 1.x routers there is also
+		a button which can be used to control the intensity of all the
+		LEDs at once, so that if they are too bright, user can dim them.
+
+		The CPLD firmware cycles between 8 levels of this global
+		brightness (from 100% to 0%), but this setting can have any
+		integer value between 0 and 255. It is therefore convenient to be

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +1 -0

+		Format: %u %u %u %u %u %u %u %u

drivers/leds/Kconfig +9 -0

index a49979f41eee..71caf45c8ac3 100644
@@ -157,6 +157,15 @@ config LEDS_EL15203000
 	  To compile this driver as a module, choose M here: the module
 	  will be called leds-el15203000.
 
+config LEDS_TURRIS_1X
+	tristate "LED support for CZ.NIC's Turris 1.x"
+	depends on LEDS_CLASS_MULTICOLOR
+	depends on OF
+	select LEDS_TRIGGERS
+	help
+	  This option enables support for LEDs found on the front side of
+	  CZ.NIC's Turris 1.x routers.
+
 config LEDS_TURRIS_OMNIA
 	tristate "LED support for CZ.NIC's Turris Omnia"
 	depends on LEDS_CLASS_MULTICOLOR

drivers/leds/Makefile +1 -0

index 4fd2f92cd198..de08083dbbca 100644
@@ -82,6 +82,7 @@ obj-$(CONFIG_LEDS_TCA6507)		+= leds-tca6507.o
 obj-$(CONFIG_LEDS_TI_LMU_COMMON)	+= leds-ti-lmu-common.o
 obj-$(CONFIG_LEDS_TLC591XX)		+= leds-tlc591xx.o
 obj-$(CONFIG_LEDS_TPS6105X)		+= leds-tps6105x.o
+obj-$(CONFIG_LEDS_TURRIS_1X)		+= leds-turris-1x.o
 obj-$(CONFIG_LEDS_TURRIS_OMNIA)		+= leds-turris-omnia.o
 obj-$(CONFIG_LEDS_WM831X_STATUS)	+= leds-wm831x-status.o
 obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o

drivers/leds/leds-turris-1x.c new file +89 -0

new file mode 100644
index 000000000000..bd566f5210c7
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0
+// (C) 2022 Pali Rohár <[email protected]>
+//
+// CZ.NIC's Turris 1.x LEDs driver, controlled by CPLD firmware:
+// https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+#include <linux/i2c.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include "leds.h"
+
+/* LED registers starts at byte 0x13 in CPLD memory map */
+#define TURRIS1X_LED_REG_OFF(reg) ((reg)-0x13)
+
+/* LEDs 1-5 share common register for setting brightness */
+#define TURRIS1X_LED_BRIGHTNESS_OFF(idx)	({ const u8 _idx = (idx) & 7; \
+						   (_idx == 0) ? 0 : \
+						   (_idx <= 5) ? 1 : \
+						   (_idx - 4); })
+
+#define TURRIS1X_LED_BRIGHTNESS_REG(idx, color)	TURRIS1X_LED_REG_OFF(0x13 + \
+						  3 * TURRIS1X_LED_BRIGHTNESS_OFF(idx) + \
+						  ((color) & 3))
+#define TURRIS1X_LED_GLOBAL_LEVEL_REG		TURRIS1X_LED_REG_OFF(0x20)
+#define TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG	TURRIS1X_LED_REG_OFF(0x21)
+#define TURRIS1X_LED_SW_OVERRIDE_REG		TURRIS1X_LED_REG_OFF(0x22)
+#define TURRIS1X_LED_SW_DISABLE_REG		TURRIS1X_LED_REG_OFF(0x23)
+#define TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(lvl)	TURRIS1X_LED_REG_OFF(0x28 + ((lvl) & 7))
+
+struct turris1x_led {
+	struct led_classdev_mc mc_cdev;
+	struct mc_subled subled_info[3];
+	u32 reg;
+	bool registered;
+};
+
+#define to_turris1x_led(l)	container_of(l, struct turris1x_led, mc_cdev)
+
+struct turris1x_leds {
+	void __iomem *regs;
+	struct mutex lock;
+	struct turris1x_led leds[8];
+};
+
+static struct led_hw_trigger_type turris1x_hw_trigger_type;
+
+static int turris1x_hwtrig_activate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Disable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val &= ~BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+
+	return 0;
+}
+
+static void turris1x_hwtrig_deactivate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Enable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val |= BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+}
+
+static struct led_trigger turris1x_hw_trigger = {
+	.name		= "turris1x-cpld",
+	.activate	= turris1x_hwtrig_activate,
+	.deactivate	= turris1x_hwtrig_deactivate,
+	.trigger_type	= &turris1x_hw_trigger_type,
+};
+
+static enum led_brightness turris1x_led_brightness_get(struct led_classdev *cdev)
+{
+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);

drivers/leds/leds-turris-1x.c new file +11 -0

+		led_mc_calc_color_components(mc_cdev, brightness);
+		for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+			writeb(mc_cdev->subled_info[i].brightness,
+			       leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(led->reg, i));
+
+		/*
+		 * LEDs 1-5 (LAN) share common color settings in same sets
+		 * of HW registers and therefore it is not possible to set
+		 * different colors. So when chaning color of one LED then
+		 * reflect color change for all of them.
+		 */

drivers/leds/leds-turris-1x.c new file +10 -0

+	mutex_unlock(&leds->lock);
+
+	return 0;
+}
+
+static int turris1x_led_register(struct device *dev, struct turris1x_leds *leds,
+				 struct device_node *np, u8 val_sw_override,
+				 u8 val_sw_disable)
+{
+	struct led_init_data init_data = {};

drivers/leds/leds-turris-1x.c new file +29 -0

+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(np, "color", &color);
+	if (ret || color != LED_COLOR_ID_RGB) {
+		dev_err(dev,
+			"Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
+			np);
+		return -EINVAL;
+	}
+
+	led = &leds->leds[reg];
+
+	if (led->registered) {
+		dev_err(dev, "Node %pOF: duplicate 'reg' property %u\n",
+			     np, reg);
+		return -EINVAL;
+	}
+
+	led->registered = true;
+	led->reg = reg;
+
+	led->subled_info[0].color_index = LED_COLOR_ID_RED;
+	led->subled_info[0].intensity = 255;
+	led->subled_info[0].channel = 0;
+	led->subled_info[1].color_index = LED_COLOR_ID_GREEN;
+	led->subled_info[1].intensity = 255;
+	led->subled_info[1].channel = 1;
+	led->subled_info[2].color_index = LED_COLOR_ID_BLUE;

drivers/leds/leds-turris-1x.c new file +5 -0

+
+	/* All LEDs except LED 6 (WiFi) can be controller by hardware trigger */
+	if (reg != 6)
+		cdev->trigger_type = &turris1x_hw_trigger_type;
+

drivers/leds/leds-turris-1x.c new file +36 -0

+	ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
+							&init_data);
+	if (ret) {
+		dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
+			       char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int brightness;
+
+	/*
+	 * Current brightness value is available in read-only register
+	 * TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG. Equivalent code is:
+	 * level = readb(leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG) & 7;
+	 * brightness = readb(leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+	 */
+	brightness = readb(leds->regs + TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG);
+
+	return sprintf(buf, "%u\n", brightness);
+}
+
+static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
+				const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	int best_error, error, level, value;
+	unsigned long brightness;
+	u8 best_level;
+
+	if (kstrtoul(buf, 10, &brightness))

drivers/leds/leds-turris-1x.c new file +136 -0

+	best_level = 0;
+	best_error = INT_MAX;
+	for (level = 0; level < 8; level++) {
+		value = readb(leds->regs +
+			      TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+		error = abs(value - (int)brightness);
+		if (best_error > error) {
+			best_error = error;
+			best_level = level;
+		}
+	}
+
+	writeb(best_level, leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG);
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness);
+
+static ssize_t brightness_values_show(struct device *dev,
+				      struct device_attribute *a, char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int i;
+
+	for (i = 0; i < 8; i++)
+		vals[i] = readb(leds->regs +
+				TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return sprintf(buf, "%u %u %u %u %u %u %u %u\n", vals[0], vals[1],
+		       vals[2], vals[3], vals[4], vals[5], vals[6], vals[7]);
+}
+
+static ssize_t brightness_values_store(struct device *dev,
+				       struct device_attribute *a,
+				       const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int nchars;
+	int i;
+
+	if (sscanf(buf, "%u %u %u %u %u %u %u %u%n", &vals[0], &vals[1],
+		   &vals[2], &vals[3], &vals[4], &vals[5], &vals[6], &vals[7],
+		   &nchars) != 8 || nchars + 1 < count)
+		return -EINVAL;
+
+	for (i = 0; i < 8; i++)
+		writeb(vals[i],
+		       leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness_values);
+
+static struct attribute *turris1x_leds_controller_attrs[] = {
+	&dev_attr_brightness.attr,
+	&dev_attr_brightness_values.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(turris1x_leds_controller);
+
+static int turris1x_leds_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev_of_node(dev);
+	struct device_node *child;
+	struct turris1x_leds *leds;
+	struct resource *res;
+	void __iomem *regs;
+	u8 val_sw_override;
+	u8 val_sw_disable;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, leds);
+
+	leds->regs = regs;
+	mutex_init(&leds->lock);
+
+	ret = devm_led_trigger_register(dev, &turris1x_hw_trigger);
+	if (ret) {
+		dev_err(dev, "Cannot register private LED trigger: %d\n", ret);
+		return ret;
+	}
+
+	val_sw_override = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val_sw_disable = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+
+	for_each_available_child_of_node(np, child) {
+		ret = turris1x_led_register(dev, leds, child,
+					    val_sw_override, val_sw_disable);
+		if (ret) {
+			of_node_put(child);
+			return ret;
+		}
+	}
+
+	ret = devm_device_add_groups(dev, turris1x_leds_controller_groups);
+	if (ret) {
+		dev_err(dev, "Could not add attribute group!\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id of_turris1x_leds_match[] = {
+	{ .compatible = "cznic,turris1x-leds" },
+	{},
+};
+
+static struct platform_driver turris1x_leds_driver = {
+	.probe = turris1x_leds_probe,
+	.driver = {
+		.name = "turris1x_leds",
+		.of_match_table = of_turris1x_leds_match,
+	},
+};
+module_platform_driver(turris1x_leds_driver);
+
+MODULE_AUTHOR("Pali Rohár <[email protected]>");
+MODULE_DESCRIPTION("CZ.NIC's Turris 1.x LEDs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:turris1x_leds");

Quoted 45 lines · On Tue, 5 Jul 2022 02:04:48 +0200 Pali Rohár <[email protected]> wrote:

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

Signed-off-by Pali Rohár <[email protected]>

---
 .../testing/sysfs-class-led-driver-turris1x   |  23 +
 drivers/leds/Kconfig                          |   9 +
 drivers/leds/Makefile                         |   1 +
 drivers/leds/leds-turris-1x.c                 | 412 ++++++++++++++++++
 4 files changed, 445 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-class-led-driver-turris1x
 create mode 100644 drivers/leds/leds-turris-1x.c

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +15 -0

new file mode 100644
index 000000000000..02be9197554d
@@ -0,0 +1,23 @@
+What:		/sys/class/leds/<led>/device/brightness
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) On the back size of the Turris 1.x routers there is also
+		a button which can be used to control the intensity of all the
+		LEDs at once, so that if they are too bright, user can dim them.
+
+		The CPLD firmware cycles between 8 levels of this global
+		brightness (from 100% to 0%), but this setting can have any
+		integer value between 0 and 255. It is therefore convenient to be
+		able to change this setting from software.
+
+		Format: %u
+

Documentation/ABI/testing/sysfs-class-led-driver-turris1x line 21

Quoted 6 lines

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +6 -0

+What:		/sys/class/leds/<led>/device/brightness_values
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) Values of all 8 levels between which CPLD firmware cycles
+		when brightness buffer is pressed.

*button

Quoted 133 lines

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +1 -0

+		Format: %u %u %u %u %u %u %u %u

drivers/leds/Kconfig +9 -0

index a49979f41eee..71caf45c8ac3 100644
@@ -157,6 +157,15 @@ config LEDS_EL15203000
 	  To compile this driver as a module, choose M here: the module
 	  will be called leds-el15203000.
 
+config LEDS_TURRIS_1X
+	tristate "LED support for CZ.NIC's Turris 1.x"
+	depends on LEDS_CLASS_MULTICOLOR
+	depends on OF
+	select LEDS_TRIGGERS
+	help
+	  This option enables support for LEDs found on the front side of
+	  CZ.NIC's Turris 1.x routers.
+
 config LEDS_TURRIS_OMNIA
 	tristate "LED support for CZ.NIC's Turris Omnia"
 	depends on LEDS_CLASS_MULTICOLOR

drivers/leds/Makefile +1 -0

index 4fd2f92cd198..de08083dbbca 100644
@@ -82,6 +82,7 @@ obj-$(CONFIG_LEDS_TCA6507)		+= leds-tca6507.o
 obj-$(CONFIG_LEDS_TI_LMU_COMMON)	+= leds-ti-lmu-common.o
 obj-$(CONFIG_LEDS_TLC591XX)		+= leds-tlc591xx.o
 obj-$(CONFIG_LEDS_TPS6105X)		+= leds-tps6105x.o
+obj-$(CONFIG_LEDS_TURRIS_1X)		+= leds-turris-1x.o
 obj-$(CONFIG_LEDS_TURRIS_OMNIA)		+= leds-turris-omnia.o
 obj-$(CONFIG_LEDS_WM831X_STATUS)	+= leds-wm831x-status.o
 obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o

drivers/leds/leds-turris-1x.c new file +94 -0

new file mode 100644
index 000000000000..bd566f5210c7
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0
+// (C) 2022 Pali Rohár <[email protected]>
+//
+// CZ.NIC's Turris 1.x LEDs driver, controlled by CPLD firmware:
+// https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+#include <linux/i2c.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include "leds.h"
+
+/* LED registers starts at byte 0x13 in CPLD memory map */
+#define TURRIS1X_LED_REG_OFF(reg) ((reg)-0x13)
+
+/* LEDs 1-5 share common register for setting brightness */
+#define TURRIS1X_LED_BRIGHTNESS_OFF(idx)	({ const u8 _idx = (idx) & 7; \
+						   (_idx == 0) ? 0 : \
+						   (_idx <= 5) ? 1 : \
+						   (_idx - 4); })
+
+#define TURRIS1X_LED_BRIGHTNESS_REG(idx, color)	TURRIS1X_LED_REG_OFF(0x13 + \
+						  3 * TURRIS1X_LED_BRIGHTNESS_OFF(idx) + \
+						  ((color) & 3))
+#define TURRIS1X_LED_GLOBAL_LEVEL_REG		TURRIS1X_LED_REG_OFF(0x20)
+#define TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG	TURRIS1X_LED_REG_OFF(0x21)
+#define TURRIS1X_LED_SW_OVERRIDE_REG		TURRIS1X_LED_REG_OFF(0x22)
+#define TURRIS1X_LED_SW_DISABLE_REG		TURRIS1X_LED_REG_OFF(0x23)
+#define TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(lvl)	TURRIS1X_LED_REG_OFF(0x28 + ((lvl) & 7))
+
+struct turris1x_led {
+	struct led_classdev_mc mc_cdev;
+	struct mc_subled subled_info[3];
+	u32 reg;
+	bool registered;
+};
+
+#define to_turris1x_led(l)	container_of(l, struct turris1x_led, mc_cdev)
+
+struct turris1x_leds {
+	void __iomem *regs;
+	struct mutex lock;
+	struct turris1x_led leds[8];
+};
+
+static struct led_hw_trigger_type turris1x_hw_trigger_type;
+
+static int turris1x_hwtrig_activate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Disable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val &= ~BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+
+	return 0;
+}
+
+static void turris1x_hwtrig_deactivate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Enable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val |= BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+}
+
+static struct led_trigger turris1x_hw_trigger = {
+	.name		= "turris1x-cpld",
+	.activate	= turris1x_hwtrig_activate,
+	.deactivate	= turris1x_hwtrig_deactivate,
+	.trigger_type	= &turris1x_hw_trigger_type,
+};
+
+static enum led_brightness turris1x_led_brightness_get(struct led_classdev *cdev)
+{
+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(mc_cdev);
+
+	if (!(readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG) & BIT(led->reg)))
+		return LED_ON;

drivers/leds/leds-turris-1x.c line 99

Quoted 5 lines

drivers/leds/leds-turris-1x.c new file +5 -0

+	else if (!(readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG) & BIT(led->reg)))
+		return LED_ON;
+	else
+		return LED_OFF;
+}

LED_ON and LED_OFF are deprecated, as says in include/linux/leds.h. Just return 0 or 1.

drivers/leds/leds-turris-1x.c line 103

Quoted 4 lines

drivers/leds/leds-turris-1x.c new file +4 -0

+
+static int turris1x_led_brightness_set_blocking(struct led_classdev *cdev,
+						enum led_brightness brightness)
+{

The register write should be immediate, we don't need to use the _blocking variant here. On Omnia we need to, cause I2C is slow.

drivers/leds/leds-turris-1x.c line 113

Quoted 10 lines

drivers/leds/leds-turris-1x.c new file +10 -0

+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(mc_cdev);
+	int i, j;
+	u8 val;
+
+	mutex_lock(&leds->lock);
+
+	/* Set new brightness value for each color when LED is enabled */
+	if (brightness == LED_ON) {

if (brightness)

So this will also make sure that I can change LED color by writing new color to multi_intensity and 1 to brightness, even if the LED is in HW control mode, am I correct?

Quoted 15 lines

drivers/leds/leds-turris-1x.c new file +15 -0

+		led_mc_calc_color_components(mc_cdev, brightness);
+		for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+			writeb(mc_cdev->subled_info[i].brightness,
+			       leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(led->reg, i));
+
+		/*
+		 * LEDs 1-5 (LAN) share common color settings in same sets
+		 * of HW registers and therefore it is not possible to set
+		 * different colors. So when chaning color of one LED then
+		 * reflect color change for all of them.
+		 */
+		if (led->reg >= 1 && led->reg <= 5) {
+			for (j = 0; j < ARRAY_SIZE(leds->leds); j++) {
+				if (leds->leds[j].reg < 1 ||
+				    leds->leds[j].reg > 5 ||

drivers/leds/leds-turris-1x.c line 134

Quoted 6 lines

drivers/leds/leds-turris-1x.c new file +6 -0

+				    leds->leds[j].reg == led->reg)
+					continue;
+				for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+					leds->leds[j].mc_cdev.subled_info[i].intensity =
+						mc_cdev->subled_info[i].intensity;
+			}

I don't consider this a problem

but suppose that we are rewriting the
other LEDs colors, and at the same time someone is reading from sysfs the multi_intensity file of a LED that is being rewritten. This can result in wrong value being read, right? But probably only on multi-core systems...

Quoted 5 lines

drivers/leds/leds-turris-1x.c new file +5 -0

+		}
+	}
+
+	/* Enable / disable LED for software control */
+	val = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);

drivers/leds/leds-turris-1x.c line 145

Quoted 6 lines

drivers/leds/leds-turris-1x.c new file +6 -0

+	if (brightness == LED_ON && (val & BIT(led->reg)))
+		writeb(val & ~BIT(led->reg),
+		       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+	else if (brightness == LED_OFF && !(val & BIT(led->reg)))
+		writeb(val | BIT(led->reg),
+		       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);

Pls just use brightness or !brightness.

Or maybe just write the value?
Is the register write expensive on the CPLD or why are you trying to avoid it if unnecessary?

Quoted 10 lines

drivers/leds/leds-turris-1x.c new file +10 -0

+	mutex_unlock(&leds->lock);
+
+	return 0;
+}
+
+static int turris1x_led_register(struct device *dev, struct turris1x_leds *leds,
+				 struct device_node *np, u8 val_sw_override,
+				 u8 val_sw_disable)
+{
+	struct led_init_data init_data = {};

drivers/leds/leds-turris-1x.c line 166

Quoted 10 lines

drivers/leds/leds-turris-1x.c new file +10 -0

+	struct led_classdev *cdev;
+	struct turris1x_led *led;
+	int ret, color;
+	u32 reg;
+
+	ret = of_property_read_u32(np, "reg", &reg);
+	if (ret || reg >= ARRAY_SIZE(leds->leds)) {
+		dev_err(dev,
+			"Node %pOF: must contain 'reg' property with values between 0 and %u\n",
+			np, (unsigned int)ARRAY_SIZE(leds->leds)-1);

Weird that checkpatch doesn't warn about spaces around the minus operator in ARRAY_SIZE()-1.

Quoted 29 lines

drivers/leds/leds-turris-1x.c new file +29 -0

+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(np, "color", &color);
+	if (ret || color != LED_COLOR_ID_RGB) {
+		dev_err(dev,
+			"Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
+			np);
+		return -EINVAL;
+	}
+
+	led = &leds->leds[reg];
+
+	if (led->registered) {
+		dev_err(dev, "Node %pOF: duplicate 'reg' property %u\n",
+			     np, reg);
+		return -EINVAL;
+	}
+
+	led->registered = true;
+	led->reg = reg;
+
+	led->subled_info[0].color_index = LED_COLOR_ID_RED;
+	led->subled_info[0].intensity = 255;
+	led->subled_info[0].channel = 0;
+	led->subled_info[1].color_index = LED_COLOR_ID_GREEN;
+	led->subled_info[1].intensity = 255;
+	led->subled_info[1].channel = 1;
+	led->subled_info[2].color_index = LED_COLOR_ID_BLUE;

drivers/leds/leds-turris-1x.c line 205

Quoted 10 lines

drivers/leds/leds-turris-1x.c new file +10 -0

+	led->subled_info[2].intensity = 255;
+	led->subled_info[2].channel = 2;
+
+	led->mc_cdev.subled_info = led->subled_info;
+	led->mc_cdev.num_colors = ARRAY_SIZE(led->subled_info);
+
+	init_data.fwnode = &np->fwnode;
+
+	cdev = &led->mc_cdev.led_cdev;
+	cdev->max_brightness = LED_ON;

s/LED_ON/1/

drivers/leds/leds-turris-1x.c line 207

Quoted 2 lines

drivers/leds/leds-turris-1x.c new file +2 -0

+	cdev->brightness_get = turris1x_led_brightness_get;
+	cdev->brightness_set_blocking = turris1x_led_brightness_set_blocking;

See above about _blocking.

Quoted 5 lines

drivers/leds/leds-turris-1x.c new file +5 -0

+
+	/* All LEDs except LED 6 (WiFi) can be controller by hardware trigger */
+	if (reg != 6)
+		cdev->trigger_type = &turris1x_hw_trigger_type;
+

drivers/leds/leds-turris-1x.c line 222

Quoted 10 lines

drivers/leds/leds-turris-1x.c new file +10 -0

+	/* Disable hardware trigger for LED 6 (WiFi) - allow software control */
+	if (reg == 6 && !(val_sw_override & BIT(6))) {
+		if (!(val_sw_disable & BIT(6))) {
+			val_sw_disable |= BIT(6);
+			writeb(val_sw_disable,
+			       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+		}
+		val_sw_override |= BIT(6);
+		writeb(val_sw_override,
+		       leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);

Again, is the register write that expensive that you try to avoid it if the corresponding bit has the value you want?

drivers/leds/leds-turris-1x.c line 229

Quoted 7 lines

drivers/leds/leds-turris-1x.c new file +7 -0

+	}
+
+	if (!(val_sw_override & BIT(reg)))
+		cdev->default_trigger = turris1x_hw_trigger.name;
+
+	if (!(val_sw_override & BIT(reg)) || !(val_sw_disable & BIT(reg)))
+		cdev->brightness = LED_ON;

s/LED_ON/1/

Quoted 42 lines

drivers/leds/leds-turris-1x.c new file +42 -0

+	ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
+							&init_data);
+	if (ret) {
+		dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
+			       char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int brightness;
+
+	/*
+	 * Current brightness value is available in read-only register
+	 * TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG. Equivalent code is:
+	 * level = readb(leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG) & 7;
+	 * brightness = readb(leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+	 */
+	brightness = readb(leds->regs + TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG);
+
+	return sprintf(buf, "%u\n", brightness);
+}
+
+static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
+				const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	int best_error, error, level, value;
+	unsigned long brightness;
+	u8 best_level;
+
+	if (kstrtoul(buf, 10, &brightness))
+		return -EINVAL;
+
+	if (brightness > 255)
+		return -EINVAL;
+
+	/*

drivers/leds/leds-turris-1x.c line 276

Quoted 4 lines

drivers/leds/leds-turris-1x.c new file +4 -0

+	 * Brightness can be set only to one of 8 predefined value levels
+	 * available in TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level) registers.
+	 * Choose level which has nearest value to the specified brightness.
+	 */

Hmm. Wouldn't it make more sense to simply have the global brightness accept values from 0 to 7, instead of mapping it to 256 values? And call it something like selected_brightness_index?

Quoted 136 lines

drivers/leds/leds-turris-1x.c new file +136 -0

+	best_level = 0;
+	best_error = INT_MAX;
+	for (level = 0; level < 8; level++) {
+		value = readb(leds->regs +
+			      TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+		error = abs(value - (int)brightness);
+		if (best_error > error) {
+			best_error = error;
+			best_level = level;
+		}
+	}
+
+	writeb(best_level, leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG);
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness);
+
+static ssize_t brightness_values_show(struct device *dev,
+				      struct device_attribute *a, char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int i;
+
+	for (i = 0; i < 8; i++)
+		vals[i] = readb(leds->regs +
+				TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return sprintf(buf, "%u %u %u %u %u %u %u %u\n", vals[0], vals[1],
+		       vals[2], vals[3], vals[4], vals[5], vals[6], vals[7]);
+}
+
+static ssize_t brightness_values_store(struct device *dev,
+				       struct device_attribute *a,
+				       const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int nchars;
+	int i;
+
+	if (sscanf(buf, "%u %u %u %u %u %u %u %u%n", &vals[0], &vals[1],
+		   &vals[2], &vals[3], &vals[4], &vals[5], &vals[6], &vals[7],
+		   &nchars) != 8 || nchars + 1 < count)
+		return -EINVAL;
+
+	for (i = 0; i < 8; i++)
+		writeb(vals[i],
+		       leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness_values);
+
+static struct attribute *turris1x_leds_controller_attrs[] = {
+	&dev_attr_brightness.attr,
+	&dev_attr_brightness_values.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(turris1x_leds_controller);
+
+static int turris1x_leds_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev_of_node(dev);
+	struct device_node *child;
+	struct turris1x_leds *leds;
+	struct resource *res;
+	void __iomem *regs;
+	u8 val_sw_override;
+	u8 val_sw_disable;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, leds);
+
+	leds->regs = regs;
+	mutex_init(&leds->lock);
+
+	ret = devm_led_trigger_register(dev, &turris1x_hw_trigger);
+	if (ret) {
+		dev_err(dev, "Cannot register private LED trigger: %d\n", ret);
+		return ret;
+	}
+
+	val_sw_override = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val_sw_disable = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+
+	for_each_available_child_of_node(np, child) {
+		ret = turris1x_led_register(dev, leds, child,
+					    val_sw_override, val_sw_disable);
+		if (ret) {
+			of_node_put(child);
+			return ret;
+		}
+	}
+
+	ret = devm_device_add_groups(dev, turris1x_leds_controller_groups);
+	if (ret) {
+		dev_err(dev, "Could not add attribute group!\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static const struct of_device_id of_turris1x_leds_match[] = {
+	{ .compatible = "cznic,turris1x-leds" },
+	{},
+};
+
+static struct platform_driver turris1x_leds_driver = {
+	.probe = turris1x_leds_probe,
+	.driver = {
+		.name = "turris1x_leds",
+		.of_match_table = of_turris1x_leds_match,
+	},
+};
+module_platform_driver(turris1x_leds_driver);
+
+MODULE_AUTHOR("Pali Rohár <[email protected]>");
+MODULE_DESCRIPTION("CZ.NIC's Turris 1.x LEDs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:turris1x_leds");

Quoted 2 lines

I don't consider this a problem

I think it is a problem, to ensure that 'cat multi_intensity' for every

Quoted 3 lines

Or maybe just write the value?
Is the register write expensive on the CPLD or why are you trying to avoid it if unnecessary?

I just do not see any reason to do unnecessary writes.

Quoted 4 lines

Hmm. Wouldn't it make more sense to simply have the global brightness accept values from 0 to 7, instead of mapping it to 256 values? And call it something like selected_brightness_index?

All other drivers have brightness entry which operates on monotone brightness property.
Brightness levels do not have to be monotone and by default are
decreasing: 0 = brightness with higher intensity; 7 = no intensity (off)

I cannot image who would like or prefer usage of such API.

Just stick with existing APIs. "brightness" entry takes intensity value which is monotone, 0 the lowest, MAX (=255) the highest.

Quoted 4 lines · On Tue, 5 Jul 2022 12:56:09 +0200 Pali Rohár <[email protected]> wrote:

Quoted 2 lines

I don't consider this a problem

I think it is a problem, to ensure that 'cat multi_intensity' for every

Misunderstanding. I meant that I don't consider the eventual inconsistency a problem, i.e. I agree with your code.

Quoted 5 lines

Quoted 3 lines

Or maybe just write the value?
Is the register write expensive on the CPLD or why are you trying to avoid it if unnecessary?

I just do not see any reason to do unnecessary writes.

But now you do an unnecessary check.

Unless the writeb() is slower than
that check. Since this isn't i2c, I am wondering how fast that writeb() is... But this is just me wondering, we can keep it the way you wrote it...

Quoted 9 lines

Quoted 4 lines

Hmm. Wouldn't it make more sense to simply have the global brightness accept values from 0 to 7, instead of mapping it to 256 values? And call it something like selected_brightness_index?

All other drivers have brightness entry which operates on monotone brightness property.
Brightness levels do not have to be monotone and by default are
decreasing: 0 = brightness with higher intensity; 7 = no intensity (off)

What do you mean all other drivers? AFAIK only one driver does this global brightness thing, and that is Omnia. The global brightness is something different from LED cdev brightness property, the same names are just coincidental (in fact it caused confusion when Pavel was first reviewing Turris Omnia driver). Maybe it should have been called global_intensity, to avoid the confusion...

Quoted 1 line

I cannot image who would like or prefer usage of such API.

One file that represents the index of the selected global intensity (as is stored internally in the CPLD) and another file that represents the configured intensities between which the button switches makes sense, IMO.

Quoted 2 lines

Just stick with existing APIs. "brightness" entry takes intensity value which is monotone, 0 the lowest, MAX (=255) the highest.

Again, the name "brightness" does not imply that it is the same thing as "brightness" of a LED cdev. And since it even doesn't live in /sys/class/<led>/ directory, we are proposing new API and can use whatever makes sense.

I am not saying that the way you did it doesn't make sense. I am just wondering if it wouldn't make more sense to be able to read the index of what the user selected by button pressing.

Marek

Quoted 11 lines · On Tuesday 05 July 2022 13:52:27 Marek Behún wrote:

Quoted 4 lines · On Tue, 5 Jul 2022 12:56:09 +0200 Pali Rohár <[email protected]> wrote:

Quoted 2 lines

I don't consider this a problem

I think it is a problem, to ensure that 'cat multi_intensity' for every

Misunderstanding. I meant that I don't consider the eventual inconsistency a problem, i.e. I agree with your code.

Quoted 7 lines

Quoted 5 lines

Quoted 3 lines

Or maybe just write the value?
Is the register write expensive on the CPLD or why are you trying to avoid it if unnecessary?

I just do not see any reason to do unnecessary writes.

But now you do an unnecessary check.

I think that testing if some bit is set in 32-bit general purpose processor register is something which really does not play role here.

Note that readb() is always needed to do because it is required to modify just one bit and this cannot be done without read-modify-write operations.

Quoted 15 lines

Unless the writeb() is slower than
that check. Since this isn't i2c, I am wondering how fast that writeb() is... But this is just me wondering, we can keep it the way you wrote it...

Quoted 9 lines

Quoted 4 lines

Hmm. Wouldn't it make more sense to simply have the global brightness accept values from 0 to 7, instead of mapping it to 256 values? And call it something like selected_brightness_index?

All other drivers have brightness entry which operates on monotone brightness property.
Brightness levels do not have to be monotone and by default are
decreasing: 0 = brightness with higher intensity; 7 = no intensity (off)

Quoted 6 lines

What do you mean all other drivers? AFAIK only one driver does this global brightness thing, and that is Omnia. The global brightness is something different from LED cdev brightness property, the same names are just coincidental (in fact it caused confusion when Pavel was first reviewing Turris Omnia driver). Maybe it should have been called global_intensity, to avoid the confusion...

Ok. I thought "brightness" == "brightness" too.

Anyway, as Omnia has this API it makes sense to use same API for other devices, this allows userspace software to be compatible with more devices.

Quoted 6 lines

Quoted 1 line

I cannot image who would like or prefer usage of such API.

One file that represents the index of the selected global intensity (as is stored internally in the CPLD) and another file that represents the configured intensities between which the button switches makes sense, IMO.

And this is the issue. If you want to get current brightness, you need to read two files and then do non-trivial logic to derive current brightness.

Quoted 8 lines

Quoted 2 lines

Just stick with existing APIs. "brightness" entry takes intensity value which is monotone, 0 the lowest, MAX (=255) the highest.

Again, the name "brightness" does not imply that it is the same thing as "brightness" of a LED cdev. And since it even doesn't live in /sys/class/<led>/ directory, we are proposing new API and can use whatever makes sense.

Quoted 5 lines

I am not saying that the way you did it doesn't make sense. I am just wondering if it wouldn't make more sense to be able to read the index of what the user selected by button pressing.

Marek

So what about exporting another sysfs file which controls current level (0-7)?

Quoted 1 line · On Tue, 5 Jul 2022 14:22:38 +0200 Pali Rohár <[email protected]> wrote:

So what about exporting another sysfs file which controls current level (0-7)?

OK, that would be satisfactory. Something like
"selected_brightness_index".

Quoted 6 lines · On Tuesday 05 July 2022 14:30:01 Marek Behún wrote:

Quoted 1 line · On Tue, 5 Jul 2022 14:22:38 +0200 Pali Rohár <[email protected]> wrote:

So what about exporting another sysfs file which controls current level (0-7)?

OK, that would be satisfactory. Something like
"selected_brightness_index".

Too long? What about just "brightness_level" and make it R/W? We already call it level (not index).

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +13 -0

new file mode 100644
index 000000000000..fd09613c8d2d
@@ -0,0 +1,116 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/cznic,turris1x-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris 1.x LEDs driver
+
+maintainers:
+  - Pali Rohár <[email protected]>
+
+description:
+  This module adds support for the RGB LEDs found on the front panel of the

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +4 -0

+
+    properties:
+      reg:
+        minimum: 0

Quoted 32 lines · Pali Rohár

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +18 -0

new file mode 100644
index 000000000000..fd09613c8d2d
@@ -0,0 +1,116 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/cznic,turris1x-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris 1.x LEDs driver
+
+maintainers:
+  - Pali Rohár <[email protected]>
+
+description:
+  This module adds support for the RGB LEDs found on the front panel of the
+  Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD
+  firmware running on Lattice FPGA. Firmware is open source and available at
+  https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+properties:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 23

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+  compatible:
+    const: cznic,turris1x-leds
+
+  reg:
+    maxItems: 2

You need to describe the items, if it is really two items. However your example has only one item, so this was not tested and won't work.

You'll get warning from Rob's robot soon... but you should test the bindings instead.

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 34

Quoted 6 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +6 -0

+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#

This looks incorrect, unless you rebased on my patchset?

Quoted 8 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +8 -0

+
+    properties:
+      reg:
+        minimum: 0
+        maximum: 7
+
+    required:
+      - reg

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 48

Quoted 6 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +6 -0

+
+additionalProperties: false
+
+examples:
+  - |
+

No blank line.

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 51

Quoted 3 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +3 -0

+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

Generic node name.

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 60

Quoted 9 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +9 -0

+        #address-cells = <1>;
+        #size-cells = <1>;
+
+        led-controller@13 {
+            compatible = "cznic,turris1x-leds";
+            reg = <0x13 0x1d>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+

Best regards,
Krzysztof

Quoted 33 lines · On Tuesday 05 July 2022 13:36:54 Krzysztof Kozlowski wrote:

Quoted 32 lines · Pali Rohár

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +18 -0

new file mode 100644
index 000000000000..fd09613c8d2d
@@ -0,0 +1,116 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/cznic,turris1x-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris 1.x LEDs driver
+
+maintainers:
+  - Pali Rohár <[email protected]>
+
+description:
+  This module adds support for the RGB LEDs found on the front panel of the
+  Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD
+  firmware running on Lattice FPGA. Firmware is open source and available at
+  https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+properties:

Quoted 8 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 23

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+  compatible:
+    const: cznic,turris1x-leds
+
+  reg:
+    maxItems: 2

You need to describe the items, if it is really two items. However your example has only one item, so this was not tested and won't work.

Ehm? Example has two items in the reg.

Quoted 3 lines

You'll get warning from Rob's robot soon... but you should test the bindings instead.

I have tested bindings on the real hardware and it is working fine together with the driver from patch 2/2.

Quoted 14 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 34

Quoted 12 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +11 -0

+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#

This looks incorrect, unless you rebased on my patchset?

So what is the correct? (I used inspiration from
cznic,turris-omnia-leds.yaml file)

Quoted 17 lines

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +4 -0

+
+    properties:
+      reg:
+        minimum: 0

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 48

Quoted 10 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +10 -0

+        maximum: 7
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+

No blank line.

Ok.

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 51

Quoted 3 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +3 -0

+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

Generic node name.

Is not cpld name generic enough?

Quoted 43 lines · Pali Rohár

Quoted 41 lines · On Tuesday 05 July 2022 13:36:54 Krzysztof Kozlowski wrote:

Quoted 27 lines · Pali Rohár

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +13 -0

new file mode 100644
index 000000000000..fd09613c8d2d
@@ -0,0 +1,116 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/cznic,turris1x-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris 1.x LEDs driver
+
+maintainers:
+  - Pali Rohár <[email protected]>
+
+description:
+  This module adds support for the RGB LEDs found on the front panel of the

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 23

Quoted 10 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +10 -0

+  Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD
+  firmware running on Lattice FPGA. Firmware is open source and available at
+  https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+properties:
+  compatible:
+    const: cznic,turris1x-leds
+
+  reg:
+    maxItems: 2

You need to describe the items, if it is really two items. However your example has only one item, so this was not tested and won't work.

Quoted 1 line

Ehm? Example has two items in the reg.

No, you have exactly one item.
<0x13 0x1d>

Two items are for example:
<0x13 0x1d>, <0x23 0x1d>

Quoted 6 lines

Quoted 3 lines

You'll get warning from Rob's robot soon... but you should test the bindings instead.

I have tested bindings on the real hardware and it is working fine together with the driver from patch 2/2.

Bindings cannot be tested on real hardware. Bindings are tested with dt_binding_check, as explained in writing-schema.rst

Quoted 15 lines

Quoted 14 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 34

Quoted 12 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +11 -0

+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#

This looks incorrect, unless you rebased on my patchset?

Quoted 2 lines

So what is the correct? (I used inspiration from
cznic,turris-omnia-leds.yaml file)

Which according to current multicolor bindings is not correct. Correct is pwm-multicolor. However if you rebase on [1], it looks fine, except missing unevaluatedProperties.

[1]
https://lore.kernel.org/all/[email protected]/

Quoted 24 lines

Quoted 17 lines

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +4 -0

+
+    properties:
+      reg:
+        minimum: 0

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 48

Quoted 10 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +10 -0

+        maximum: 7
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+

No blank line.

Ok.

Quoted 4 lines

Quoted 3 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +3 -0

+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

Quoted 3 lines

Quoted 1 line

Generic node name.

Is not cpld name generic enough?

No, it means nothing to me. Just like "a", "ashjd" or "wrls".

"The name of a node should be somewhat generic, reflecting the function of the device and not its precise programming
model. If appropriate, the name should be one of the following choices:"

Best regards,
Krzysztof

Quoted 5 lines

Quoted 4 lines

Quoted 2 lines

You need to describe the items, if it is really two items. However your example has only one item, so this was not tested and won't work.

Ehm? Example has two items in the reg.

Quoted 5 lines

No, you have exactly one item.
<0x13 0x1d>

Two items are for example:
<0x13 0x1d>, <0x23 0x1d>

Ok. So I should change maxItems to 1 in this case?

And how you want to describe those items?

Quoted 8 lines

Quoted 7 lines

Quoted 4 lines

You'll get warning from Rob's robot soon... but you should test the bindings instead.

I have tested bindings on the real hardware and it is working fine together with the driver from patch 2/2.

Quoted 2 lines

Bindings cannot be tested on real hardware. Bindings are tested with dt_binding_check, as explained in writing-schema.rst

Ou... this is something which I was not able to run, it just does not work, throws lot of python dependency hell errors and it spend more than hour with it. So sorry, I really cannot run it. Maybe it would be a wise to provide web service for these checks for those who cannot run them locally?

Quoted 19 lines

Quoted 18 lines

Quoted 15 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 34

Quoted 13 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +11 -0

+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#

This looks incorrect, unless you rebased on my patchset?

So what is the correct? (I used inspiration from
cznic,turris-omnia-leds.yaml file)

Quoted 3 lines

Which according to current multicolor bindings is not correct. Correct is pwm-multicolor. However if you rebase on [1], it looks fine, except missing unevaluatedProperties.

Ok. So does it mean that I should just add
"unevaluatedProperties: false"?

Quoted 30 lines

[1]
https://lore.kernel.org/all/[email protected]/

Quoted 26 lines

Quoted 17 lines

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +4 -0

+
+    properties:
+      reg:
+        minimum: 0

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 48

Quoted 10 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +10 -0

+        maximum: 7
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+

No blank line.

Ok.

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 51

Quoted 3 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +3 -0

+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

Generic node name.

Quoted 3 lines

Quoted 1 line

Is not cpld name generic enough?

No, it means nothing to me. Just like "a", "ashjd" or "wrls".

If you never heard about it, I would suggest to read something about Programmable logic devices. It is interesting category of hardware with which you can play. CPLD and FPGA are very often used in lot of products and FPGA is very easy for playing and programming custom logic.

For example on wikipedia is list of different technologies of programmable logic devices:
https://en.wikipedia.org/wiki/Programmable_logic_device

So if you want more generic name, just name it "pld"?

But as it is CPLD
device I would suggest to name it really as "cpld". It does not matter from which manufactor you have CPLD, just like it does not matter from which manufactor you have NAND.

From bus point of view, cpld is like nand or nor nodes in DTS. All of them refers to specific memory map of chip selects on the local bus.

Quoted 3 lines

"The name of a node should be somewhat generic, reflecting the function of the device and not its precise programming
model. If appropriate, the name should be one of the following choices:"

Hm... You forgot to send what are those "choices:"?

Quoted 5 lines · Pali Rohár

Quoted 5 lines

Quoted 4 lines

Quoted 2 lines

You need to describe the items, if it is really two items. However your example has only one item, so this was not tested and won't work.

Ehm? Example has two items in the reg.

Quoted 7 lines

Quoted 5 lines

No, you have exactly one item.
<0x13 0x1d>

Two items are for example:
<0x13 0x1d>, <0x23 0x1d>

Ok. So I should change maxItems to 1 in this case?

Yes

Quoted 2 lines

And how you want to describe those items?

In that case, no need to describe.

Quoted 8 lines

Quoted 8 lines

Quoted 7 lines

Quoted 4 lines

You'll get warning from Rob's robot soon... but you should test the bindings instead.

I have tested bindings on the real hardware and it is working fine together with the driver from patch 2/2.

Quoted 8 lines

Quoted 2 lines

Bindings cannot be tested on real hardware. Bindings are tested with dt_binding_check, as explained in writing-schema.rst

Ou... this is something which I was not able to run, it just does not work, throws lot of python dependency hell errors and it spend more than hour with it. So sorry, I really cannot run it. Maybe it would be a wise to provide web service for these checks for those who cannot run them locally?

It's one pip command to install and one make command to run... I would say easy to start using, unless of course you use some unusual distro without Python 3 (cannot believe nowadays...) or without pip.

Rob's bot will test it for you.

Anyway, in such case please mark your bindings always as RFT, so we will not waste time on reviewing obvious stuff which is found by automated tools. I think we both agree that reviewers time should not be used for trivial stuff already pointed out by compiler/linter/automation.

Quoted 23 lines

Quoted 22 lines

Quoted 16 lines

Quoted 15 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 34

Quoted 13 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +11 -0

+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#

This looks incorrect, unless you rebased on my patchset?

Quoted 2 lines

So what is the correct? (I used inspiration from
cznic,turris-omnia-leds.yaml file)

Which according to current multicolor bindings is not correct. Correct is pwm-multicolor. However if you rebase on [1], it looks fine, except missing unevaluatedProperties.

Quoted 2 lines

Ok. So does it mean that I should just add
"unevaluatedProperties: false"?

Yes, on that level of indentation, so:
$ref: leds-class-multicolor.yaml#
unevaluatedProperties: false

Quoted 34 lines

Quoted 33 lines

[1]
https://lore.kernel.org/all/[email protected]/

Quoted 20 lines

Quoted 17 lines

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +4 -0

+
+    properties:
+      reg:
+        minimum: 0

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 48

Quoted 10 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +10 -0

+        maximum: 7
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+

No blank line.

Ok.

Quoted 7 lines

Quoted 5 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 51

Quoted 3 lines

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +3 -0

+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

Generic node name.

Is not cpld name generic enough?

No, it means nothing to me. Just like "a", "ashjd" or "wrls".

Quoted 4 lines

If you never heard about it, I would suggest to read something about Programmable logic devices. It is interesting category of hardware with which you can play. CPLD and FPGA are very often used in lot of products and FPGA is very easy for playing and programming custom logic.

The are many different acronyms in the language so without context might be tricky to connect the dots.

Quoted 6 lines

For example on wikipedia is list of different technologies of programmable logic devices:
https://en.wikipedia.org/wiki/Programmable_logic_device

So if you want more generic name, just name it "pld"?

That one would be fine.

Quoted 4 lines

But as it is CPLD
device I would suggest to name it really as "cpld". It does not matter from which manufactor you have CPLD, just like it does not matter from which manufactor you have NAND.

Then cpld is fine as well.

Quoted 8 lines

From bus point of view, cpld is like nand or nor nodes in DTS. All of them refers to specific memory map of chip selects on the local bus.

Quoted 3 lines

"The name of a node should be somewhat generic, reflecting the function of the device and not its precise programming
model. If appropriate, the name should be one of the following choices:"

Quoted 1 line

Hm... You forgot to send what are those "choices:"?

I didn't, I just assumed you will Google it (or use other web-search engine of your choice) to get the spec. As this is a quote, Google results should be very accurate. No need to duplicate entire pages of publicly available specification.

Best regards,
Krzysztof

This was the first thing which I did when I read email. No usable result. So the next thing was that I started git grep on the linux tree. Again no result. So at the end I come to the conclusion that you forgot to copy+paste whole quote or something like that.

Now I started searching a bit more and found it in following documentation:
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

Original link to the quote would be useful (but now I have it).

I have tested bindings on the real hardware and it is working fine together with the driver from patch 2/2.

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 116 ++++++++++++++++++
 1 file changed, 116 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

Signed-off-by Pali Rohár <[email protected]>

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

drivers/leds/Kconfig +4 -0

+       select LEDS_TRIGGERS
+       help
+         This option enables support for LEDs found on the front side of
+         CZ.NIC's Turris 1.x routers.

(quoted diff) +2 -0

+               return 0;
+}

drivers/leds/leds-turris-1x.c new file +8 -0

+                                   leds->leds[j].reg == led->reg)
+                                       continue;
+                               for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+                                       leds->leds[j].mc_cdev.subled_info[i].intensity =
+                                               mc_cdev->subled_info[i].intensity;
+                       }
+               }
+       }

drivers/leds/leds-turris-1x.c new file +15 -0

+       ret = of_property_read_u32(np, "reg", &reg);
+       if (ret || reg >= ARRAY_SIZE(leds->leds)) {
+               dev_err(dev,
+                       "Node %pOF: must contain 'reg' property with values between 0 and %u\n",
+                       np, (unsigned int)ARRAY_SIZE(leds->leds) - 1);
+               return -EINVAL;
+       }
+
+       ret = of_property_read_u32(np, "color", &color);
+       if (ret || color != LED_COLOR_ID_RGB) {
+               dev_err(dev,
+                       "Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
+                       np);
+               return -EINVAL;
+       }

drivers/leds/leds-turris-1x.c new file +9 -0

+       ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
+                                                       &init_data);
+       if (ret) {
+               dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
+               return ret;
+       }
+
+       return 0;
+}

drivers/leds/leds-turris-1x.c new file +5 -0

+static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
+                              char *buf)
+{
+       struct turris1x_leds *leds = dev_get_drvdata(dev);
+       unsigned int brightness;

+}

+ */

+ error = abs(value - (int)brightness);

+}

+}

+};

+ regs = devm_ioremap_resource(dev, res);

drivers/leds/leds-turris-1x.c new file +2 -0

+       if (IS_ERR(regs))
+               return PTR_ERR(regs);

+ }

+ for_each_available_child_of_node(np, child) {

drivers/leds/leds-turris-1x.c new file +3 -0

+                       return ret;
+               }
+       }

drivers/leds/leds-turris-1x.c new file +4 -0

+       }
+
+       return 0;
+}

drivers/leds/leds-turris-1x.c new file +2 -0

+        * So reset LEDs to default state before kernel reboots.
+        */

+ writeb(0xff,

drivers/leds/leds-turris-1x.c new file +3 -0

+                              leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(i, j));
+       }
+}

+};

Quoted 10 lines · Pali Rohár

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

Quoted 4 lines

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

Pardon me, but this driver seems like 3 years old by the APIs it's using... I have to say this, because I was surprised a lot to see some calls.

Quoted 14 lines · On Tuesday 05 July 2022 20:40:26 Andy Shevchenko wrote:

Quoted 13 lines · Pali Rohár

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

Quoted 5 lines

Quoted 1 line

This driver uses the multicolor LED framework and HW led triggers.

Pardon me, but this driver seems like 3 years old by the APIs it's using... I have to say this, because I was surprised a lot to see some calls.

I wrote it just recently according to other omnia multicolor driver.

This adds support for the RGB LEDs found on the front panel of the Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD firmware running on Lattice FPGA.

CPLD firmware provides HW triggering mode for all LEDs except WiFi LED which is automatically enabled after power on reset. LAN LEDs share HW registers for RGB colors settings, so it is not possible to set different colors for individual LAN LEDs.

CZ.NIC CPLD firmware is open source and available at:
https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v

This driver uses the multicolor LED framework and HW led triggers.

Signed-off-by Pali Rohár <[email protected]>

---
Changes in v2:
* Use 0/1 instead of LED_OFF/LED_ON
* Add brightness_level device attribute
* Implement callback brightness_set instead of brightness_set_blocking
* Reset LEDs to default state before kernel reboots

---
 .../testing/sysfs-class-led-driver-turris1x   |  31 ++
 drivers/leds/Kconfig                          |   9 +
 drivers/leds/Makefile                         |   1 +
 drivers/leds/leds-turris-1x.c                 | 474 ++++++++++++++++++
 4 files changed, 515 insertions(+)
 create mode 100644 Documentation/ABI/testing/sysfs-class-led-driver-turris1x
 create mode 100644 drivers/leds/leds-turris-1x.c

Documentation/ABI/testing/sysfs-class-led-driver-turris1x new file +31 -0

new file mode 100644
index 000000000000..bb8b82b43165
@@ -0,0 +1,31 @@
+What:		/sys/class/leds/<led>/device/brightness
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) On the back size of the Turris 1.x routers there is also
+		a button which can be used to control the intensity of all the
+		LEDs at once, so that if they are too bright, user can dim them.
+
+		The CPLD firmware cycles between 8 levels of this global
+		brightness (from 100% to 0%), but this setting can have any
+		integer value between 0 and 255. It is therefore convenient to be
+		able to change this setting from software.
+
+		Format: %u
+
+What:		/sys/class/leds/<led>/device/brightness_level
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) Current brightness level value (0-7).
+
+		Format: %u
+
+What:		/sys/class/leds/<led>/device/brightness_values
+Date:		July 2022
+KernelVersion:	5.20
+Contact:	Pali Rohár <[email protected]>
+Description:	(RW) Values of all 8 levels between which CPLD firmware cycles
+		when brightness button is pressed.
+
+		Format: %u %u %u %u %u %u %u %u

drivers/leds/Kconfig +9 -0

index a49979f41eee..71caf45c8ac3 100644
@@ -157,6 +157,15 @@ config LEDS_EL15203000
 	  To compile this driver as a module, choose M here: the module
 	  will be called leds-el15203000.
 
+config LEDS_TURRIS_1X
+	tristate "LED support for CZ.NIC's Turris 1.x"
+	depends on LEDS_CLASS_MULTICOLOR
+	depends on OF
+	select LEDS_TRIGGERS
+	help
+	  This option enables support for LEDs found on the front side of
+	  CZ.NIC's Turris 1.x routers.
+
 config LEDS_TURRIS_OMNIA
 	tristate "LED support for CZ.NIC's Turris Omnia"
 	depends on LEDS_CLASS_MULTICOLOR

drivers/leds/Makefile +1 -0

index 4fd2f92cd198..de08083dbbca 100644
@@ -82,6 +82,7 @@ obj-$(CONFIG_LEDS_TCA6507)		+= leds-tca6507.o
 obj-$(CONFIG_LEDS_TI_LMU_COMMON)	+= leds-ti-lmu-common.o
 obj-$(CONFIG_LEDS_TLC591XX)		+= leds-tlc591xx.o
 obj-$(CONFIG_LEDS_TPS6105X)		+= leds-tps6105x.o
+obj-$(CONFIG_LEDS_TURRIS_1X)		+= leds-turris-1x.o
 obj-$(CONFIG_LEDS_TURRIS_OMNIA)		+= leds-turris-omnia.o
 obj-$(CONFIG_LEDS_WM831X_STATUS)	+= leds-wm831x-status.o
 obj-$(CONFIG_LEDS_WM8350)		+= leds-wm8350.o

drivers/leds/leds-turris-1x.c new file +474 -0

new file mode 100644
index 000000000000..cf7567b64306
@@ -0,0 +1,474 @@
+// SPDX-License-Identifier: GPL-2.0
+// (C) 2022 Pali Rohár <[email protected]>
+//
+// CZ.NIC's Turris 1.x LEDs driver, controlled by CPLD firmware:
+// https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+#include <linux/i2c.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include "leds.h"
+
+/* LED registers starts at byte 0x13 in CPLD memory map */
+#define TURRIS1X_LED_REG_OFF(reg) ((reg)-0x13)
+
+/* LEDs 1-5 share common register for setting brightness */
+#define TURRIS1X_LED_BRIGHTNESS_OFF(idx)	({ const u8 _idx = (idx) & 7; \
+						   (_idx == 0) ? 0 : \
+						   (_idx <= 5) ? 1 : \
+						   (_idx - 4); })
+
+#define TURRIS1X_LED_BRIGHTNESS_REG(idx, color)	TURRIS1X_LED_REG_OFF(0x13 + \
+						  3 * TURRIS1X_LED_BRIGHTNESS_OFF(idx) + \
+						  ((color) & 3))
+#define TURRIS1X_LED_GLOBAL_LEVEL_REG		TURRIS1X_LED_REG_OFF(0x20)
+#define TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG	TURRIS1X_LED_REG_OFF(0x21)
+#define TURRIS1X_LED_SW_OVERRIDE_REG		TURRIS1X_LED_REG_OFF(0x22)
+#define TURRIS1X_LED_SW_DISABLE_REG		TURRIS1X_LED_REG_OFF(0x23)
+#define TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(lvl)	TURRIS1X_LED_REG_OFF(0x28 + ((lvl) & 7))
+
+struct turris1x_led {
+	struct led_classdev_mc mc_cdev;
+	struct mc_subled subled_info[3];
+	u32 reg;
+	bool registered;
+};
+
+#define to_turris1x_led(l)	container_of(l, struct turris1x_led, mc_cdev)
+
+struct turris1x_leds {
+	void __iomem *regs;
+	struct mutex lock;
+	struct turris1x_led leds[8];
+};
+
+static struct led_hw_trigger_type turris1x_hw_trigger_type;
+
+static int turris1x_hwtrig_activate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Disable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val &= ~BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+
+	return 0;
+}
+
+static void turris1x_hwtrig_deactivate(struct led_classdev *cdev)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(lcdev_to_mccdev(cdev));
+	u8 val;
+
+	/* Enable software control of LED */
+	mutex_lock(&leds->lock);
+	val = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val |= BIT(led->reg);
+	writeb(val, leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	mutex_unlock(&leds->lock);
+}
+
+static struct led_trigger turris1x_hw_trigger = {
+	.name		= "turris1x-cpld",
+	.activate	= turris1x_hwtrig_activate,
+	.deactivate	= turris1x_hwtrig_deactivate,
+	.trigger_type	= &turris1x_hw_trigger_type,
+};
+
+static enum led_brightness turris1x_led_brightness_get(struct led_classdev *cdev)
+{
+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(mc_cdev);
+
+	if (!(readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG) & BIT(led->reg)))
+		return 1;
+	else if (!(readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG) & BIT(led->reg)))
+		return 1;
+	else
+		return 0;
+}
+
+static void turris1x_led_brightness_set(struct led_classdev *cdev,
+					enum led_brightness brightness)
+{
+	struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
+	struct turris1x_leds *leds = dev_get_drvdata(cdev->dev->parent);
+	struct turris1x_led *led = to_turris1x_led(mc_cdev);
+	int i, j;
+	u8 val;
+
+	mutex_lock(&leds->lock);
+
+	/* Set new brightness value for each color when LED is enabled */
+	if (brightness) {
+		led_mc_calc_color_components(mc_cdev, brightness);
+		for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+			writeb(mc_cdev->subled_info[i].brightness,
+			       leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(led->reg, i));
+
+		/*
+		 * LEDs 1-5 (LAN) share common color settings in same sets
+		 * of HW registers and therefore it is not possible to set
+		 * different colors. So when chaning color of one LED then
+		 * reflect color change for all of them.
+		 */
+		if (led->reg >= 1 && led->reg <= 5) {
+			for (j = 0; j < ARRAY_SIZE(leds->leds); j++) {
+				if (leds->leds[j].reg < 1 ||
+				    leds->leds[j].reg > 5 ||
+				    leds->leds[j].reg == led->reg)
+					continue;
+				for (i = 0; i < ARRAY_SIZE(led->subled_info); i++)
+					leds->leds[j].mc_cdev.subled_info[i].intensity =
+						mc_cdev->subled_info[i].intensity;
+			}
+		}
+	}
+
+	/* Enable / disable LED for software control */
+	val = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+	if (brightness && (val & BIT(led->reg)))
+		writeb(val & ~BIT(led->reg),
+		       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+	else if (!brightness && !(val & BIT(led->reg)))
+		writeb(val | BIT(led->reg),
+		       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+
+	mutex_unlock(&leds->lock);
+}
+
+static int turris1x_led_register(struct device *dev, struct turris1x_leds *leds,
+				 struct device_node *np, u8 val_sw_override,
+				 u8 val_sw_disable)
+{
+	struct led_init_data init_data = {};
+	struct led_classdev *cdev;
+	struct turris1x_led *led;
+	int ret, color;
+	u32 reg;
+	int i;
+
+	const unsigned int colors[ARRAY_SIZE(led->subled_info)] = {
+		LED_COLOR_ID_RED, LED_COLOR_ID_GREEN, LED_COLOR_ID_BLUE
+	};
+
+	ret = of_property_read_u32(np, "reg", &reg);
+	if (ret || reg >= ARRAY_SIZE(leds->leds)) {
+		dev_err(dev,
+			"Node %pOF: must contain 'reg' property with values between 0 and %u\n",
+			np, (unsigned int)ARRAY_SIZE(leds->leds) - 1);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(np, "color", &color);
+	if (ret || color != LED_COLOR_ID_RGB) {
+		dev_err(dev,
+			"Node %pOF: must contain 'color' property with value LED_COLOR_ID_RGB\n",
+			np);
+		return -EINVAL;
+	}
+
+	led = &leds->leds[reg];
+
+	if (led->registered) {
+		dev_err(dev, "Node %pOF: duplicate 'reg' property %u\n",
+			     np, reg);
+		return -EINVAL;
+	}
+
+	led->registered = true;
+	led->reg = reg;
+
+	/* Set initial colors to what are currently in use */
+	for (i = 0; i < ARRAY_SIZE(led->subled_info); i++) {
+		led->subled_info[i].intensity =
+			readb(leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(reg, i));
+		led->subled_info[i].color_index = colors[i];
+		led->subled_info[i].channel = i;
+	}
+
+	led->mc_cdev.subled_info = led->subled_info;
+	led->mc_cdev.num_colors = ARRAY_SIZE(led->subled_info);
+
+	init_data.fwnode = &np->fwnode;
+
+	cdev = &led->mc_cdev.led_cdev;
+	cdev->max_brightness = 1;
+	cdev->brightness_get = turris1x_led_brightness_get;
+	cdev->brightness_set = turris1x_led_brightness_set;
+
+	/* All LEDs except LED 6 (WiFi) can be controller by hardware trigger */
+	if (reg != 6)
+		cdev->trigger_type = &turris1x_hw_trigger_type;
+
+	/* Disable hardware trigger for LED 6 (WiFi) - allow software control */
+	if (reg == 6 && !(val_sw_override & BIT(6))) {
+		if (!(val_sw_disable & BIT(6))) {
+			val_sw_disable |= BIT(6);
+			writeb(val_sw_disable,
+			       leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+		}
+		val_sw_override |= BIT(6);
+		writeb(val_sw_override,
+		       leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	}
+
+	if (!(val_sw_override & BIT(reg)))
+		cdev->default_trigger = turris1x_hw_trigger.name;
+
+	if (!(val_sw_override & BIT(reg)) || !(val_sw_disable & BIT(reg)))
+		cdev->brightness = 1;
+
+	ret = devm_led_classdev_multicolor_register_ext(dev, &led->mc_cdev,
+							&init_data);
+	if (ret) {
+		dev_err(dev, "Cannot register LED %pOF: %i\n", np, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static ssize_t brightness_show(struct device *dev, struct device_attribute *a,
+			       char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int brightness;
+
+	/*
+	 * Current brightness value is available in read-only register
+	 * TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG. Equivalent code is:
+	 * level = readb(leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG) & 7;
+	 * brightness = readb(leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+	 */
+	brightness = readb(leds->regs + TURRIS1X_LED_GET_GLOBAL_BRIGHTNESS_REG);
+
+	return sprintf(buf, "%u\n", brightness);
+}
+
+static ssize_t brightness_store(struct device *dev, struct device_attribute *a,
+				const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	int best_error, error, level, value;
+	unsigned long brightness;
+	u8 best_level;
+
+	if (kstrtoul(buf, 10, &brightness))
+		return -EINVAL;
+
+	if (brightness > 255)
+		return -EINVAL;
+
+	/*
+	 * Brightness can be set only to one of 8 predefined value levels
+	 * available in TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level) registers.
+	 * Choose level which has nearest value to the specified brightness.
+	 */
+	best_level = 0;
+	best_error = INT_MAX;
+	for (level = 0; level < 8; level++) {
+		value = readb(leds->regs +
+			      TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(level));
+		error = abs(value - (int)brightness);
+		if (best_error > error) {
+			best_error = error;
+			best_level = level;
+		}
+	}
+
+	writeb(best_level, leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG);
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness);
+
+static ssize_t brightness_level_show(struct device *dev,
+				     struct device_attribute *a, char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int level;
+
+	level = readb(leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG) & 7;
+
+	return sprintf(buf, "%u\n", level);
+}
+
+static ssize_t brightness_level_store(struct device *dev,
+				      struct device_attribute *a,
+				      const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned long level;
+
+	if (kstrtoul(buf, 10, &level))
+		return -EINVAL;
+
+	if (level > 7)
+		return -EINVAL;
+
+	writeb(level, leds->regs + TURRIS1X_LED_GLOBAL_LEVEL_REG);
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness_level);
+
+static ssize_t brightness_values_show(struct device *dev,
+				      struct device_attribute *a, char *buf)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int i;
+
+	for (i = 0; i < 8; i++)
+		vals[i] = readb(leds->regs +
+				TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return sprintf(buf, "%u %u %u %u %u %u %u %u\n", vals[0], vals[1],
+		       vals[2], vals[3], vals[4], vals[5], vals[6], vals[7]);
+}
+
+static ssize_t brightness_values_store(struct device *dev,
+				       struct device_attribute *a,
+				       const char *buf, size_t count)
+{
+	struct turris1x_leds *leds = dev_get_drvdata(dev);
+	unsigned int vals[8];
+	int nchars;
+	int i;
+
+	if (sscanf(buf, "%u %u %u %u %u %u %u %u%n", &vals[0], &vals[1],
+		   &vals[2], &vals[3], &vals[4], &vals[5], &vals[6], &vals[7],
+		   &nchars) != 8 || nchars + 1 < count)
+		return -EINVAL;
+
+	for (i = 0; i < 8; i++)
+		writeb(vals[i],
+		       leds->regs + TURRIS1X_LED_GLOBAL_BRIGHTNESS_REG(i));
+
+	return count;
+}
+static DEVICE_ATTR_RW(brightness_values);
+
+static struct attribute *turris1x_leds_controller_attrs[] = {
+	&dev_attr_brightness.attr,
+	&dev_attr_brightness_level.attr,
+	&dev_attr_brightness_values.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(turris1x_leds_controller);
+
+static int turris1x_leds_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev_of_node(dev);
+	struct device_node *child;
+	struct turris1x_leds *leds;
+	struct resource *res;
+	void __iomem *regs;
+	u8 val_sw_override;
+	u8 val_sw_disable;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, leds);
+
+	leds->regs = regs;
+	mutex_init(&leds->lock);
+
+	ret = devm_led_trigger_register(dev, &turris1x_hw_trigger);
+	if (ret) {
+		dev_err(dev, "Cannot register private LED trigger: %d\n", ret);
+		return ret;
+	}
+
+	val_sw_override = readb(leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+	val_sw_disable = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+
+	for_each_available_child_of_node(np, child) {
+		ret = turris1x_led_register(dev, leds, child,
+					    val_sw_override, val_sw_disable);
+		if (ret) {
+			of_node_put(child);
+			return ret;
+		}
+	}
+
+	ret = devm_device_add_groups(dev, turris1x_leds_controller_groups);
+	if (ret) {
+		dev_err(dev, "Could not add attribute group!\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static void turris1x_leds_shutdown(struct platform_device *pdev)
+{
+	struct turris1x_leds *leds = platform_get_drvdata(pdev);
+	int i, j;
+	u8 val;
+
+	/*
+	 * LED registers are persisent across board resets.
+	 * So reset LEDs to default state before kernel reboots.
+	 */
+
+	/* Disable software control of all LEDs except LED 6 (WiFi) */
+	writeb(BIT(6), leds->regs + TURRIS1X_LED_SW_OVERRIDE_REG);
+
+	/* Turn off LED 6 (WiFi) as there is no hardware trigger for it */
+	val = readb(leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+	writeb(val | BIT(6), leds->regs + TURRIS1X_LED_SW_DISABLE_REG);
+
+	/* Reset colors of all LEDs to default values */
+	for (i = 0; i < ARRAY_SIZE(leds->leds); i++) {
+		/* Skip LAN2-LAN5 LEDs which share color register with LAN1 */
+		if (i >= 2 && i <= 5)
+			continue;
+		for (j = 0; j < ARRAY_SIZE(leds->leds[i].subled_info); j++)
+			writeb(0xff,
+			       leds->regs + TURRIS1X_LED_BRIGHTNESS_REG(i, j));
+	}
+}
+
+static const struct of_device_id of_turris1x_leds_match[] = {
+	{ .compatible = "cznic,turris1x-leds" },
+	{},
+};
+
+static struct platform_driver turris1x_leds_driver = {
+	.probe = turris1x_leds_probe,
+	.shutdown = turris1x_leds_shutdown,
+	.driver = {
+		.name = "turris1x_leds",
+		.of_match_table = of_turris1x_leds_match,
+	},
+};
+module_platform_driver(turris1x_leds_driver);
+
+MODULE_AUTHOR("Pali Rohár <[email protected]>");
+MODULE_DESCRIPTION("CZ.NIC's Turris 1.x LEDs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:turris1x_leds");

Signature · 1 line

2.20.1

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
Changes in v2:
* Fix schema errors

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 118 ++++++++++++++++++
 1 file changed, 118 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +54 -0

new file mode 100644
index 000000000000..bcaab5b03128
@@ -0,0 +1,118 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/cznic,turris1x-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: CZ.NIC's Turris 1.x LEDs driver
+
+maintainers:
+  - Pali Rohár <[email protected]>
+
+description:
+  This module adds support for the RGB LEDs found on the front panel of the
+  Turris 1.x routers. There are 8 RGB LEDs that are controlled by CZ.NIC CPLD
+  firmware running on Lattice FPGA. Firmware is open source and available at
+  https://gitlab.nic.cz/turris/hw/turris_cpld/-/blob/master/CZ_NIC_Router_CPLD.v
+
+properties:
+  compatible:
+    const: cznic,turris1x-leds
+
+  reg:
+    description: CPLD address range where LED registers are mapped
+    maxItems: 1
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+patternProperties:
+  "^multi-led@[0-7]$":
+    type: object
+    $ref: leds-class-multicolor.yaml#
+    unevaluatedProperties: false
+
+    properties:
+      reg:
+        minimum: 0
+        maximum: 7
+
+    required:
+      - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {
+        #address-cells = <1>;
+        #size-cells = <1>;

Add device-tree bindings documentation for Turris 1.x RGB LEDs.

Signed-off-by Pali Rohár <[email protected]>

---
Changes in v2:
* Fix schema errors

---
 .../bindings/leds/cznic,turris1x-leds.yaml    | 118 ++++++++++++++++++
 1 file changed, 118 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 52

Quoted 5 lines · On Tue, 5 Jul 2022 17:59:28 +0200 Pali Rohár <[email protected]> wrote:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {

The generic node name should be just "bus". That it is a CPLD implementation should come from compatible string.

Quoted 11 lines · On Wednesday 06 July 2022 13:15:07 Marek Behún wrote:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 52

Quoted 5 lines · On Tue, 5 Jul 2022 17:59:28 +0200 Pali Rohár <[email protected]> wrote:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {  

The generic node name should be just "bus". That it is a CPLD implementation should come from compatible string.

Sorry, I do not understand why "bus". Why other memory chips are named e.g. "nand" or "nor" and not "bus" too?

By this logic should not be _every_ node called just "bus"? Hm... and are names needed at all then?

Quoted 13 lines · On Wed, 6 Jul 2022 13:19:12 +0200 Pali Rohár <[email protected]> wrote:

Quoted 11 lines · On Wednesday 06 July 2022 13:15:07 Marek Behún wrote:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml line 52

Quoted 5 lines · On Tue, 5 Jul 2022 17:59:28 +0200 Pali Rohár <[email protected]> wrote:

Documentation/devicetree/bindings/leds/cznic,turris1x-leds.yaml new file +5 -0

+examples:
+  - |
+    #include <dt-bindings/leds/common.h>
+
+    cpld@3,0 {  

The generic node name should be just "bus". That it is a CPLD implementation should come from compatible string.

Quoted 2 lines

Sorry, I do not understand why "bus". Why other memory chips are named e.g. "nand" or "nor" and not "bus" too?

As far as I understand this is because that is the preferred name for busses and this is a bus, since there is also the simple-bus compatible.

Quoted 2 lines

By this logic should not be _every_ node called just "bus"? Hm... and are names needed at all then?

:-)