Add DT support for netxbig LEDs

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
  .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
  .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
  drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
  include/dt-bindings/leds/leds-netxbig.h            |  18 ++
  4 files changed, 369 insertions(+), 21 deletions(-)

create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file +22 -0

new file mode 100644
index 000000000000..50ec2e690701
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +92 -0

new file mode 100644
index 000000000000..efadbecbfeb9
@@ -0,0 +1,92 @@
+Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
+boards (Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-leds".
+- gpio-ext: Phandle for the gpio-ext bus.
+
+Optional properties:
+- timers: Timer array. Each timer entry is represented by three integers:
+  Mode (gpio-ext bus), delay_on and delay_off.
+
+Each LED is represented as a sub-node of the netxbig-leds device.
+
+Required sub-node properties:
+- mode-addr: Mode register address on gpio-ext bus.
+- mode-val: Mode to value mapping. Each entry is represented by two integers:
+  A mode and the corresponding value on the gpio-ext bus.
+- bright-addr: Brightness register address on gpio-ext bus.
+- bright-max: Maximum brightness value.
+
+Optional sub-node properties:
+- label: Name for this LED. If omitted, the label is taken from the node name.
+- linux,default-trigger: Trigger assigned to the LED.
+
+Example:
+
+netxbig-leds {
+	compatible = "lacie,netxbig-leds";
+
+	gpio-ext = &gpio_ext;
+
+	timers = <NETXBIG_LED_TIMER1 500 500
+		  NETXBIG_LED_TIMER2 500 1000>;
+
+	blue-power {
+		label = "netxbig:blue:power";
+		mode-addr = <0>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 1
+			    NETXBIG_LED_TIMER1 3
+			    NETXBIG_LED_TIMER2 7>;
+		bright-addr = <1>;
+		bright-max = <7>;
+	};
+	red-power {
+		label = "netxbig:red:power";
+		mode-addr = <0>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <1>;
+		bright-max = <7>;
+	};
+	blue-sata0 {
+		label = "netxbig:blue:sata0";
+		mode-addr = <3>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 7
+			    NETXBIG_LED_SATA 1
+			    NETXBIG_LED_TIMER1 3>;
+		bright-addr = <2>;
+		bright-max = <7>;
+	};
+	red-sata0 {
+		label = "netxbig:red:sata0";
+		mode-addr = <3>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <2>;
+		bright-max = <7>;
+	};
+	blue-sata1 {
+		label = "netxbig:blue:sata1";
+		mode-addr = <4>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 7
+			    NETXBIG_LED_SATA 1
+			    NETXBIG_LED_TIMER1 3>;
+		bright-addr = <2>;
+		bright-max = <7>;
+	};
+	red-sata1 {
+		label = "netxbig:red:sata1";
+		mode-addr = <4>;
+		mode-val = <NETXBIG_LED_OFF 0
+			    NETXBIG_LED_ON 2
+			    NETXBIG_LED_TIMER1 4>;
+		bright-addr = <2>;
+		bright-max = <7>;
+	};
+};

drivers/leds/leds-netxbig.c +60 -5

index 25e419752a7b..dcd8302cccaf 100644
@@ -26,6 +26,7 @@
  #include <linux/spinlock.h>
  #include <linux/platform_device.h>
  #include <linux/gpio.h>
+#include <linux/of_gpio.h>
  #include <linux/leds.h>
  #include <linux/platform_data/leds-kirkwood-netxbig.h>
 

@@ -140,6 +141,11 @@ struct netxbig_led_data {
  	spinlock_t		lock;
  };
 
+struct netxbig_led_priv {
+	struct netxbig_led_platform_data *pdata;
+	struct netxbig_led_data leds_data[];
+};
+
  static int netxbig_led_get_timer_mode(enum netxbig_led_mode *mode,
  				      unsigned long delay_on,
  				      unsigned long delay_off,

@@ -304,12 +310,12 @@ static void delete_netxbig_led(struct netxbig_led_data *led_dat)
  	led_classdev_unregister(&led_dat->cdev);
  }
 
-static int
-create_netxbig_led(struct platform_device *pdev,
-		   struct netxbig_led_data *led_dat,
-		   const struct netxbig_led *template)
+static int create_netxbig_led(struct platform_device *pdev, int led,
+			      struct netxbig_led_priv *priv)
  {
-	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct netxbig_led_platform_data *pdata = priv->pdata;
+	struct netxbig_led_data *led_dat = &priv->leds_data[led];
+	const struct netxbig_led *template = &priv->pdata->leds[led];
 
  	spin_lock_init(&led_dat->lock);
  	led_dat->gpio_ext = pdata->gpio_ext;

@@ -346,38 +352,249 @@ create_netxbig_led(struct platform_device *pdev,
  	return led_classdev_register(&pdev->dev, &led_dat->cdev);
  }
 
+#ifdef CONFIG_OF_GPIO
+static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
+				 struct netxbig_gpio_ext *gpio_ext)
+{
+	int *addr, *data;
+	int num_addr, num_data;
+	int ret;
+	int i;
+
+	ret = of_gpio_named_count(np, "addr-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property addr-gpios\n");
+		return ret;
+	}
+	num_addr = ret;
+	addr = devm_kzalloc(dev, num_addr * sizeof(*addr), GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	for (i = 0; i < num_addr; i++) {
+		ret = of_get_named_gpio(np, "addr-gpios", i);
+		if (ret < 0)
+			return ret;
+		addr[i] = ret;
+	}
+	gpio_ext->addr = addr;
+	gpio_ext->num_addr = num_addr;
+
+	ret = of_gpio_named_count(np, "data-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property data-gpios\n");
+		return ret;
+	}
+	num_data = ret;
+	data = devm_kzalloc(dev, num_data * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	for (i = 0; i < num_data; i++) {
+		ret = of_get_named_gpio(np, "data-gpios", i);
+		if (ret < 0)
+			return ret;
+		data[i] = ret;
+	}
+	gpio_ext->data = data;
+	gpio_ext->num_data = num_data;
+

drivers/leds/leds-netxbig.c +72 -0

+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *gpio_ext_np;
+	struct device_node *child;
+	struct netxbig_gpio_ext *gpio_ext;
+	struct netxbig_led_timer *timers;
+	struct netxbig_led *leds, *led;
+	int num_timers;
+	int num_leds = 0;
+	int ret;
+	int i;
+
+	/* GPIO extension */
+	gpio_ext_np = of_parse_phandle(np, "gpio-ext", 0);
+	if (!gpio_ext_np) {
+		dev_err(dev, "Failed to get DT handle gpio-ext\n");
+		return -EINVAL;
+	}
+
+	gpio_ext = devm_kzalloc(dev, sizeof(*gpio_ext), GFP_KERNEL);
+	if (!gpio_ext)
+		return -ENOMEM;
+	ret = gpio_ext_get_of_pdata(dev, gpio_ext_np, gpio_ext);
+	if (ret)
+		return ret;
+	of_node_put(gpio_ext_np);
+	pdata->gpio_ext = gpio_ext;
+
+	/* Timers (optional) */
+	ret = of_property_count_u32_elems(np, "timers");
+	if (ret > 0) {
+		if (ret % 3)
+			return -EINVAL;
+		num_timers = ret / 3;
+		timers = devm_kzalloc(dev, num_timers * sizeof(*timers),
+				      GFP_KERNEL);
+		if (!timers)
+			return -ENOMEM;
+		for (i = 0; i < num_timers; i++) {
+			u32 tmp;
+
+			of_property_read_u32_index(np, "timers", 3 * i,
+						   &timers[i].mode);
+			if (timers[i].mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			of_property_read_u32_index(np, "timers",
+						   3 * i + 1, &tmp);
+			timers[i].delay_on = tmp;
+			of_property_read_u32_index(np, "timers",
+						   3 * i + 2, &tmp);
+			timers[i].delay_off = tmp;
+		}
+		pdata->timer = timers;
+		pdata->num_timer = num_timers;
+	}
+
+	/* LEDs */
+	num_leds = of_get_child_count(np);
+	if (!num_leds) {
+		dev_err(dev, "No LED subnodes found in DT\n");
+		return -ENODEV;
+	}
+
+	leds = devm_kzalloc(dev, num_leds * sizeof(*leds), GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	led = leds;
+	for_each_child_of_node(np, child) {
+		const char *string;

drivers/leds/leds-netxbig.c +46 -0

+		mode_val =
+			devm_kzalloc(dev,
+				     NETXBIG_LED_MODE_NUM * sizeof(*mode_val),
+				     GFP_KERNEL);
+		if (!mode_val)
+			return -ENOMEM;
+
+		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
+			mode_val[i] = NETXBIG_LED_INVALID_MODE;
+
+		ret = of_property_count_u32_elems(child, "mode-val");
+		if (ret < 0 || ret % 2)
+			return -EINVAL;
+		num_modes = ret / 2;
+		if (num_modes > NETXBIG_LED_MODE_NUM)
+			return -EINVAL;
+
+		for (i = 0; i < num_modes; i++) {
+			int mode;
+			int val;
+
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i, &mode);
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i + 1, &val);
+			if (mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			mode_val[mode] = val;
+		}
+		led->mode_val = mode_val;
+
+		if (!of_property_read_string(child, "label", &string))
+			led->name = string;
+		else
+			led->name = child->name;
+
+		if (!of_property_read_string(child,
+					     "linux,default-trigger", &string))
+			led->default_trigger = string;
+
+		led++;
+	}
+
+	pdata->leds = leds;
+	pdata->num_leds = num_leds;
+

drivers/leds/leds-netxbig.c +27 -16

+{
+	return -ENODEV;
+}
+#endif /* CONFIG_OF_GPIO */
+
  static int netxbig_led_probe(struct platform_device *pdev)
  {
  	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	struct netxbig_led_data *leds_data;
+	struct netxbig_led_priv *priv;
  	int i;
  	int ret;
 
-	if (!pdata)
-		return -EINVAL;
+	if (!pdata) {
+		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+		if (!pdata)
+			return -ENOMEM;
+		ret = netxbig_leds_get_of_pdata(&pdev->dev, pdata);
+		if (ret)
+			return ret;
+	}
 
-	leds_data = devm_kzalloc(&pdev->dev,
-		sizeof(struct netxbig_led_data) * pdata->num_leds, GFP_KERNEL);
-	if (!leds_data)
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv) +
+			    pdata->num_leds * sizeof(struct netxbig_led_data),
+			    GFP_KERNEL);
+	if (!priv)
  		return -ENOMEM;
+	priv->pdata = pdata;
 
  	ret = gpio_ext_init(pdata->gpio_ext);
  	if (ret < 0)
  		return ret;
 
  	for (i = 0; i < pdata->num_leds; i++) {
-		ret = create_netxbig_led(pdev, &leds_data[i], &pdata->leds[i]);
+		ret = create_netxbig_led(pdev, i, priv);
  		if (ret < 0)
  			goto err_free_leds;
  	}
-
-	platform_set_drvdata(pdev, leds_data);
+	platform_set_drvdata(pdev, priv);
 
  	return 0;
 
  err_free_leds:
  	for (i = i - 1; i >= 0; i--)
-		delete_netxbig_led(&leds_data[i]);
+		delete_netxbig_led(&priv->leds_data[i]);
 
  	gpio_ext_free(pdata->gpio_ext);
  	return ret;

@@ -385,14 +602,12 @@ err_free_leds:
 
  static int netxbig_led_remove(struct platform_device *pdev)
  {
-	struct netxbig_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
-	struct netxbig_led_data *leds_data;
+	struct netxbig_led_priv *priv = platform_get_drvdata(pdev);
+	struct netxbig_led_platform_data *pdata = priv->pdata;
  	int i;
 
-	leds_data = platform_get_drvdata(pdev);
-
  	for (i = 0; i < pdata->num_leds; i++)
-		delete_netxbig_led(&leds_data[i]);
+		delete_netxbig_led(&priv->leds_data[i]);
 
  	gpio_ext_free(pdata->gpio_ext);
 

@@ -403,7 +618,8 @@ static struct platform_driver netxbig_led_driver = {
  	.probe		= netxbig_led_probe,
  	.remove		= netxbig_led_remove,
  	.driver		= {
-		.name	= "leds-netxbig",
+		.name		= "leds-netxbig",
+		.of_match_table	= of_match_ptr(of_netxbig_leds_match),
  	},
  };
 

include/dt-bindings/leds/leds-netxbig.h new file +18 -0

new file mode 100644
index 000000000000..92658b0310b2
@@ -0,0 +1,18 @@
+/*
+ * This header provides constants for netxbig LED bindings.
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#ifndef _DT_BINDINGS_LEDS_NETXBIG_H
+#define _DT_BINDINGS_LEDS_NETXBIG_H
+
+#define NETXBIG_LED_OFF		0
+#define NETXBIG_LED_ON		1
+#define NETXBIG_LED_SATA	2
+#define NETXBIG_LED_TIMER1	3
+#define NETXBIG_LED_TIMER2	4
+
+#endif /* _DT_BINDINGS_LEDS_NETXBIG_H */

Hi Simon,

Please find my comments in the code below.

Quoted 40 lines

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
 .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
 .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
 drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
 include/dt-bindings/leds/leds-netxbig.h            |  18 ++
 4 files changed, 369 insertions(+), 21 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
 create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
 create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Quoted 57 lines

drivers/leds/leds-netxbig.c +57 -0

+#ifdef CONFIG_OF_GPIO
+static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
+				 struct netxbig_gpio_ext *gpio_ext)
+{
+	int *addr, *data;
+	int num_addr, num_data;
+	int ret;
+	int i;
+
+	ret = of_gpio_named_count(np, "addr-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property addr-gpios\n");
+		return ret;
+	}
+	num_addr = ret;
+	addr = devm_kzalloc(dev, num_addr * sizeof(*addr), GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	for (i = 0; i < num_addr; i++) {
+		ret = of_get_named_gpio(np, "addr-gpios", i);
+		if (ret < 0)
+			return ret;
+		addr[i] = ret;
+	}
+	gpio_ext->addr = addr;
+	gpio_ext->num_addr = num_addr;
+
+	ret = of_gpio_named_count(np, "data-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property data-gpios\n");
+		return ret;
+	}
+	num_data = ret;
+	data = devm_kzalloc(dev, num_data * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	for (i = 0; i < num_data; i++) {
+		ret = of_get_named_gpio(np, "data-gpios", i);
+		if (ret < 0)
+			return ret;
+		data[i] = ret;
+	}
+	gpio_ext->data = data;
+	gpio_ext->num_data = num_data;
+
+	ret = of_get_named_gpio(np, "enable-gpio", 0);
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to get GPIO from DT property enable-gpio\n");
+		return ret;
+	}
+	gpio_ext->enable = ret;
+

Review

Quoted 2 lines

(quoted diff) +2 -0

+	return 0;
+}

Since netxbig-gpio-ext extension bus can be also used to control other device, and the related DT bindings are meant for GPIO subsystem, then the above parser should also be placed there to make it available for reuse by other drivers. The gpio_ext_init function should be also moved to GPIO subsystem, presumably to the same module.

Moreover, if you switched to using devm* prefixed version of gpio_request_one and led_classdev_reqister, you could simplify the error paths in the driver.

Quoted 14 lines

drivers/leds/leds-netxbig.c +13 -0

+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *gpio_ext_np;
+	struct device_node *child;
+	struct netxbig_gpio_ext *gpio_ext;
+	struct netxbig_led_timer *timers;
+	struct netxbig_led *leds, *led;
+	int num_timers;
+	int num_leds = 0;
+	int ret;
+	int i;

Quoted 7 lines

drivers/leds/leds-netxbig.c +7 -0

+	led = leds;
+	for_each_child_of_node(np, child) {
+		const char *string;
+		int *mode_val;
+		int num_modes;
+
+		if (of_property_read_u32(child, "mode-addr",

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 496

Quoted 6 lines

drivers/leds/leds-netxbig.c +6 -0

+					 &led->mode_addr))
+			return -EINVAL;
+
+		if (of_property_read_u32(child, "bright-addr",
+					 &led->bright_addr))
+			return -EINVAL;

You don't parse bright-max DT property anywhere, AFAICT.

Quoted 51 lines

drivers/leds/leds-netxbig.c +50 -0

+		mode_val =
+			devm_kzalloc(dev,
+				     NETXBIG_LED_MODE_NUM * sizeof(*mode_val),
+				     GFP_KERNEL);
+		if (!mode_val)
+			return -ENOMEM;
+
+		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
+			mode_val[i] = NETXBIG_LED_INVALID_MODE;
+
+		ret = of_property_count_u32_elems(child, "mode-val");
+		if (ret < 0 || ret % 2)
+			return -EINVAL;
+		num_modes = ret / 2;
+		if (num_modes > NETXBIG_LED_MODE_NUM)
+			return -EINVAL;
+
+		for (i = 0; i < num_modes; i++) {
+			int mode;
+			int val;
+
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i, &mode);
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i + 1, &val);
+			if (mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			mode_val[mode] = val;
+		}
+		led->mode_val = mode_val;
+
+		if (!of_property_read_string(child, "label", &string))
+			led->name = string;
+		else
+			led->name = child->name;
+
+		if (!of_property_read_string(child,
+					     "linux,default-trigger", &string))
+			led->default_trigger = string;
+
+		led++;
+	}
+
+	pdata->leds = leds;
+	pdata->num_leds = num_leds;
+
+	return 0;
+}
+
+static const struct of_device_id of_netxbig_leds_match[] = {

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 553

Quoted 6 lines

drivers/leds/leds-netxbig.c +6 -0

+	{ .compatible = "lacie,netxbig-leds", },
+	{},
+};
+#else
+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)

s/static int/static inline int/

Quoted 3 lines · Jacek Anaszewski

Hi Simon,

Please find my comments in the code below.

Hi Jacek,

Thanks for the quick review.

Quoted 42 lines · Simon Guinot

Quoted 40 lines

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
  .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
  .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
  drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
  include/dt-bindings/leds/leds-netxbig.h            |  18 ++
  4 files changed, 369 insertions(+), 21 deletions(-)

create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

...

Quoted 57 lines

Quoted 57 lines

drivers/leds/leds-netxbig.c +57 -0

+#ifdef CONFIG_OF_GPIO
+static int gpio_ext_get_of_pdata(struct device *dev, struct device_node *np,
+				 struct netxbig_gpio_ext *gpio_ext)
+{
+	int *addr, *data;
+	int num_addr, num_data;
+	int ret;
+	int i;
+
+	ret = of_gpio_named_count(np, "addr-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property addr-gpios\n");
+		return ret;
+	}
+	num_addr = ret;
+	addr = devm_kzalloc(dev, num_addr * sizeof(*addr), GFP_KERNEL);
+	if (!addr)
+		return -ENOMEM;
+
+	for (i = 0; i < num_addr; i++) {
+		ret = of_get_named_gpio(np, "addr-gpios", i);
+		if (ret < 0)
+			return ret;
+		addr[i] = ret;
+	}
+	gpio_ext->addr = addr;
+	gpio_ext->num_addr = num_addr;
+
+	ret = of_gpio_named_count(np, "data-gpios");
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to count GPIOs in DT property data-gpios\n");
+		return ret;
+	}
+	num_data = ret;
+	data = devm_kzalloc(dev, num_data * sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	for (i = 0; i < num_data; i++) {
+		ret = of_get_named_gpio(np, "data-gpios", i);
+		if (ret < 0)
+			return ret;
+		data[i] = ret;
+	}
+	gpio_ext->data = data;
+	gpio_ext->num_data = num_data;
+
+	ret = of_get_named_gpio(np, "enable-gpio", 0);
+	if (ret < 0) {
+		dev_err(dev,
+			"Failed to get GPIO from DT property enable-gpio\n");
+		return ret;
+	}
+	gpio_ext->enable = ret;
+

Quoted 8 lines

Review

Quoted 2 lines

(quoted diff) +2 -0

+	return 0;
+}

Since netxbig-gpio-ext extension bus can be also used to control other device, and the related DT bindings are meant for GPIO subsystem, then the above parser should also be placed there to make it available for reuse by other drivers. The gpio_ext_init function should be also moved to GPIO subsystem, presumably to the same module.

Yes, this patch series is a first step. I am planning to move the netxbig-gpio-ext extension bus into a dedicated driver as soon as I need need it for an another device/driver. But for the time being, I was planning to keep it here. If you agree with that of course.

Quoted 4 lines

Moreover, if you switched to using devm* prefixed version of gpio_request_one and led_classdev_reqister, you could simplify the error paths in the driver.

Yes, I have a pending patch for this conversion. But since it is not really related with the subject of this patch series (add DT support), I was planning to send it next.

Do you want me to include this patch into this series.

Quoted 14 lines

Quoted 14 lines

drivers/leds/leds-netxbig.c +13 -0

+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)
+{
+	struct device_node *np = dev->of_node;
+	struct device_node *gpio_ext_np;
+	struct device_node *child;
+	struct netxbig_gpio_ext *gpio_ext;
+	struct netxbig_led_timer *timers;
+	struct netxbig_led *leds, *led;
+	int num_timers;
+	int num_leds = 0;
+	int ret;
+	int i;

...

Quoted 7 lines

Quoted 7 lines

drivers/leds/leds-netxbig.c +7 -0

+	led = leds;
+	for_each_child_of_node(np, child) {
+		const char *string;
+		int *mode_val;
+		int num_modes;
+
+		if (of_property_read_u32(child, "mode-addr",

Quoted 8 lines

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 496

Quoted 6 lines

drivers/leds/leds-netxbig.c +6 -0

+					 &led->mode_addr))
+			return -EINVAL;
+
+		if (of_property_read_u32(child, "bright-addr",
+					 &led->bright_addr))
+			return -EINVAL;

You don't parse bright-max DT property anywhere, AFAICT.

Yes I don't. I have added this bright-max property thinking ahead of moving the netxbig-gpio-ext stuff into a dedicated driver. For now, it is possible to compute bright-max from the number of data GPIOs of the extension bus. But once it will be removed something else will be needed. That's why I introduced this property.

But now, I am thinking I should have used this property right now. It will be more convenient when moving the netxbig-gpio-ext code out.

I'll do that for the next round.

Quoted 51 lines

Quoted 51 lines

drivers/leds/leds-netxbig.c +50 -0

+		mode_val =
+			devm_kzalloc(dev,
+				     NETXBIG_LED_MODE_NUM * sizeof(*mode_val),
+				     GFP_KERNEL);
+		if (!mode_val)
+			return -ENOMEM;
+
+		for (i = 0; i < NETXBIG_LED_MODE_NUM; i++)
+			mode_val[i] = NETXBIG_LED_INVALID_MODE;
+
+		ret = of_property_count_u32_elems(child, "mode-val");
+		if (ret < 0 || ret % 2)
+			return -EINVAL;
+		num_modes = ret / 2;
+		if (num_modes > NETXBIG_LED_MODE_NUM)
+			return -EINVAL;
+
+		for (i = 0; i < num_modes; i++) {
+			int mode;
+			int val;
+
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i, &mode);
+			of_property_read_u32_index(child,
+						   "mode-val", 2 * i + 1, &val);
+			if (mode >= NETXBIG_LED_MODE_NUM)
+				return -EINVAL;
+			mode_val[mode] = val;
+		}
+		led->mode_val = mode_val;
+
+		if (!of_property_read_string(child, "label", &string))
+			led->name = string;
+		else
+			led->name = child->name;
+
+		if (!of_property_read_string(child,
+					     "linux,default-trigger", &string))
+			led->default_trigger = string;
+
+		led++;
+	}
+
+	pdata->leds = leds;
+	pdata->num_leds = num_leds;
+
+	return 0;
+}
+
+static const struct of_device_id of_netxbig_leds_match[] = {

Quoted 8 lines

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 553

Quoted 6 lines

drivers/leds/leds-netxbig.c +6 -0

+	{ .compatible = "lacie,netxbig-leds", },
+	{},
+};
+#else
+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)

s/static int/static inline int/

Is that not already the case with modern compiler ?

Quoted 5 lines

Quoted 4 lines

Moreover, if you switched to using devm* prefixed version of gpio_request_one and led_classdev_reqister, you could simplify the error paths in the driver.

Quoted 5 lines

Yes, I have a pending patch for this conversion. But since it is not really related with the subject of this patch series (add DT support), I was planning to send it next.

Do you want me to include this patch into this series.

Why not, if you have it ready to go. If it needs some polishing, we can live with what we have now.

Quoted 10 lines

Quoted 9 lines

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 553

Quoted 7 lines

drivers/leds/leds-netxbig.c +7 -0

+static const struct of_device_id of_netxbig_leds_match[] = {
+	{ .compatible = "lacie,netxbig-leds", },
+	{},
+};
+#else
+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)

s/static int/static inline int/

Quoted 1 line

Is that not already the case with modern compiler ?

Could you elaborate on this?

Quoted 5 lines · Jacek Anaszewski

Quoted 5 lines

Quoted 4 lines

Moreover, if you switched to using devm* prefixed version of gpio_request_one and led_classdev_reqister, you could simplify the error paths in the driver.

Quoted 8 lines

Quoted 5 lines

Yes, I have a pending patch for this conversion. But since it is not really related with the subject of this patch series (add DT support), I was planning to send it next.

Do you want me to include this patch into this series.

Why not, if you have it ready to go. If it needs some polishing, we can live with what we have now.

No, the patch is ready. I'll add it.

Quoted 12 lines

Quoted 11 lines

Quoted 9 lines

drivers/leds/leds-netxbig.c create_netxbig_led(struct platform_device *pdev, · line 553

Quoted 7 lines

drivers/leds/leds-netxbig.c +7 -0

+static const struct of_device_id of_netxbig_leds_match[] = {
+	{ .compatible = "lacie,netxbig-leds", },
+	{},
+};
+#else
+static int netxbig_leds_get_of_pdata(struct device *dev,
+				     struct netxbig_led_platform_data *pdata)

s/static int/static inline int/

Is that not already the case with modern compiler ?

Quoted 1 line

Could you elaborate on this?

There is not much to say. netxbig_leds_get_of_pdata is a single line of code. I am not a gcc expert but I am quite confident that this function will be inlined anyway (given the optimisation level used to compile the Linux kernel). That's it.

But there is nothing wrong by adding "inline" neither.

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
 .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
 .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
 drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
 include/dt-bindings/leds/leds-netxbig.h            |  18 ++
 4 files changed, 369 insertions(+), 21 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
 create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
 create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file +22 -0

new file mode 100644
index 000000000000..50ec2e690701
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +0 -0

new file mode 100644
index 000000000000..efadbecbfeb9

Quoted 75 lines

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
 .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
 .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
 drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
 include/dt-bindings/leds/leds-netxbig.h            |  18 ++
 4 files changed, 369 insertions(+), 21 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
 create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
 create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file +22 -0

new file mode 100644
index 000000000000..50ec2e690701
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +0 -0

new file mode 100644
index 000000000000..efadbecbfeb9
@@ -0,0 +1,92 @@

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 6

Quoted 6 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +6 -0

+Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
+boards (Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-leds".
+- gpio-ext: Phandle for the gpio-ext bus.

Would being a subnode of gpio-ext work instead?

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 17

Quoted 12 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +11 -0

+
+Optional properties:
+- timers: Timer array. Each timer entry is represented by three integers:
+  Mode (gpio-ext bus), delay_on and delay_off.
+
+Each LED is represented as a sub-node of the netxbig-leds device.
+
+Required sub-node properties:
+- mode-addr: Mode register address on gpio-ext bus.
+- mode-val: Mode to value mapping. Each entry is represented by two integers:
+  A mode and the corresponding value on the gpio-ext bus.

I somewhat wonder if this is too low level and should just be in the driver instead. I guess with only 3 addr and data lines, it is okay. It wouldn't scale to a large number of registers though.

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 19

Quoted 3 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +2 -0

+- bright-addr: Brightness register address on gpio-ext bus.
+- bright-max: Maximum brightness value.

We already have a somewhat standard max-brightness property.

On Mon, Sep 21, 2015 at 10:38:45AM -0500, Rob Herring wrote:

Hi Rob,

Thanks for your feedback. Please, see my answers below.

Quoted 76 lines · Simon Guinot

Quoted 75 lines

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
  .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
  .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
  drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
  include/dt-bindings/leds/leds-netxbig.h            |  18 ++
  4 files changed, 369 insertions(+), 21 deletions(-)

create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file +22 -0

new file mode 100644
index 000000000000..50ec2e690701
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +0 -0

new file mode 100644
index 000000000000..efadbecbfeb9
@@ -0,0 +1,92 @@

Quoted 8 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 6

Quoted 6 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +6 -0

+Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
+boards (Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-leds".
+- gpio-ext: Phandle for the gpio-ext bus.

Would being a subnode of gpio-ext work instead?

Well, it is really unclear to me. I think that the GPIO extension bus can be seen as a "kind of" GPIO chip. And devices which are using a GPIO resource are not represented in DT as sub-nodes of the GPIO node. That's why I chose to use a phandle here.

Let me know if this representation is not correct.

Quoted 16 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 17

Quoted 12 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +11 -0

+
+Optional properties:
+- timers: Timer array. Each timer entry is represented by three integers:
+  Mode (gpio-ext bus), delay_on and delay_off.
+
+Each LED is represented as a sub-node of the netxbig-leds device.
+
+Required sub-node properties:
+- mode-addr: Mode register address on gpio-ext bus.
+- mode-val: Mode to value mapping. Each entry is represented by two integers:
+  A mode and the corresponding value on the gpio-ext bus.

I somewhat wonder if this is too low level and should just be in the driver instead. I guess with only 3 addr and data lines, it is okay. It wouldn't scale to a large number of registers though.

Even if it is not the case now, note that this values could be different for an another board. For example, we already have some x86-based boards (still no mainlined yet) which are using the leds-netxbig driver but with a different gpio-ext configuration. This could happen with some ARM-based boards too.

That's why I think it is better to have this properties in the DT rather than hardcoded values in the driver.

Quoted 5 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 19

Quoted 3 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +2 -0

+- bright-addr: Brightness register address on gpio-ext bus.
+- bright-max: Maximum brightness value.

We already have a somewhat standard max-brightness property.

Yes, Jacek mentioned that too. It made the change in the v5.

Thanks,

Simon

Hi Rob.

If you are satisfied with Simon's explanation, could you confirm that with your ack, please?

Quoted 128 lines · Rob Herring

Hi Rob,

Thanks for your feedback. Please, see my answers below.

Quoted 76 lines · Simon Guinot

Quoted 75 lines

This patch adds device tree support for the netxbig LEDs.

This also introduces a additionnal DT binding for the GPIO extension bus (netxbig-gpio-ext) used to configure the LEDs. Since this bus could also be used to control other devices, then it seems more suitable to have it in a separate DT binding.

Signed-off-by Simon Guinot <[email protected]>

Acked-by Linus Walleij <[email protected]>

---
 .../devicetree/bindings/gpio/netxbig-gpio-ext.txt  |  22 ++
 .../devicetree/bindings/leds/leds-netxbig.txt      |  92 ++++++++
 drivers/leds/leds-netxbig.c                        | 258 +++++++++++++++++++--
 include/dt-bindings/leds/leds-netxbig.h            |  18 ++
 4 files changed, 369 insertions(+), 21 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt
 create mode 100644 Documentation/devicetree/bindings/leds/leds-netxbig.txt
 create mode 100644 include/dt-bindings/leds/leds-netxbig.h

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file +22 -0

new file mode 100644
index 000000000000..50ec2e690701
@@ -0,0 +1,22 @@
+Binding for the GPIO extension bus found on some LaCie/Seagate boards
+(Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-gpio-ext".
+- addr-gpios: GPIOs representing the address register (LSB -> MSB).
+- data-gpios: GPIOs representing the data register (LSB -> MSB).
+- enable-gpio: latches the new configuration (address, data) on raising edge.
+
+Example:
+
+netxbig_gpio_ext: netxbig-gpio-ext {
+	compatible = "lacie,netxbig-gpio-ext";
+
+	addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH
+		      &gpio1 16 GPIO_ACTIVE_HIGH
+		      &gpio1 17 GPIO_ACTIVE_HIGH>;
+	data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH
+		      &gpio1 13 GPIO_ACTIVE_HIGH
+		      &gpio1 14 GPIO_ACTIVE_HIGH>;
+	enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>;
+};

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +0 -0

new file mode 100644
index 000000000000..efadbecbfeb9
@@ -0,0 +1,92 @@

Quoted 8 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 6

Quoted 6 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +6 -0

+Binding for the CPLD LEDs (GPIO extension bus) found on some LaCie/Seagate
+boards (Example: 2Big/5Big Network v2, 2Big NAS).
+
+Required properties:
+- compatible: "lacie,netxbig-leds".
+- gpio-ext: Phandle for the gpio-ext bus.

Would being a subnode of gpio-ext work instead?

Well, it is really unclear to me. I think that the GPIO extension bus can be seen as a "kind of" GPIO chip. And devices which are using a GPIO resource are not represented in DT as sub-nodes of the GPIO node. That's why I chose to use a phandle here.

Let me know if this representation is not correct.

Quoted 16 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt line 17

Quoted 12 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +11 -0

+
+Optional properties:
+- timers: Timer array. Each timer entry is represented by three integers:
+  Mode (gpio-ext bus), delay_on and delay_off.
+
+Each LED is represented as a sub-node of the netxbig-leds device.
+
+Required sub-node properties:
+- mode-addr: Mode register address on gpio-ext bus.
+- mode-val: Mode to value mapping. Each entry is represented by two integers:
+  A mode and the corresponding value on the gpio-ext bus.

I somewhat wonder if this is too low level and should just be in the driver instead. I guess with only 3 addr and data lines, it is okay. It wouldn't scale to a large number of registers though.

Even if it is not the case now, note that this values could be different for an another board. For example, we already have some x86-based boards (still no mainlined yet) which are using the leds-netxbig driver but with a different gpio-ext configuration. This could happen with some ARM-based boards too.

That's why I think it is better to have this properties in the DT rather than hardcoded values in the driver.

Quoted 4 lines

Quoted 3 lines

Documentation/devicetree/bindings/leds/leds-netxbig.txt new file +2 -0

+- bright-addr: Brightness register address on gpio-ext bus.
+- bright-max: Maximum brightness value.

Quoted 8 lines

Quoted 1 line

We already have a somewhat standard max-brightness property.

Yes, Jacek mentioned that too. It made the change in the v5.

Thanks,

Simon

_______________________________________________
linux-arm-kernel mailing list
[email protected]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Hello,

This patch series adds DT support for the LEDs found on the Kirkwood-based LaCie boards 2Big and 5Big Network v2.

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Jacek,

I did not convert the bright-max DT property into led-max-microamp. The reason is that I can't translate the bright-max values into microamperes.

Therefore, it looks more consistent to keep the same naming prefix for the bright-addr and bright-max DT properties.

Hi Simon,

Thanks for the update.

Quoted 27 lines · Simon Guinot

Hello,

This patch series adds DT support for the LEDs found on the Kirkwood-based LaCie boards 2Big and 5Big Network v2.

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Quoted 5 lines

Jacek,

I did not convert the bright-max DT property into led-max-microamp. The reason is that I can't translate the bright-max values into microamperes.

Doesn't specification of your device say what current value given brightness level reflects?

Quoted 38 lines · Jacek Anaszewski

Hi Simon,

Thanks for the update.

Quoted 32 lines · Simon Guinot

Hello,

This patch series adds DT support for the LEDs found on the Kirkwood-based LaCie boards 2Big and 5Big Network v2.

Changes for v2:
- Check timer mode value retrieved from DT.
- In netxbig_leds_get_of_pdata, don't use unsigned long variables to get timer delay values from DT with function of_property_read_u32_index. Instead, use a temporary u32 variable. This allows to silence a static checker warning.
- Make timer property optional in the binding documentation. It is now aligned with the driver code.

Changes for v3:
- Fix pointer usage with the temporary u32 variable while calling of_property_read_u32_index.

Changes for v4:
- In DT binding document netxbig-gpio-ext.txt, detail byte order for registers and latch mechanism for "enable-gpio".
- In leds-netxbig.c, add some error messages.
- In leds-netxbig.c, fix some "sizeof" style issues.
- In leds-netxbig.c, in netxbig_leds_get_of_pdata(), move the of_property_read_string() calls after the error-prone checks.
- Add some Acked-by.

Jacek,

I did not convert the bright-max DT property into led-max-microamp. The reason is that I can't translate the bright-max values into microamperes.

Quoted 2 lines

Doesn't specification of your device say what current value given brightness level reflects?

I double-checked and I can confirm that I don't have the current values for the LEDs. Although this feature is nice to have, it has not been used by the LaCie stock firmware. LEDs are only enabled at their maximum level. I believe it is the reason why it has not been specified...