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goldfish: virtual input event driver

PATCH In review Alan Cox 2 participants 2 messages Jan 21, 2013 – Jan 22, 2013

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Alan Cox

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#0 lore raw

PATCH 1/1 goldfish: virtual input event driver

From: Brian Swetland <[email protected]>

This device is a direct pipe from "hardware" to the input event subsystem, allowing us to avoid having to route "keypad" style events through an AT keyboard driver (gross!)

As with the other submissions this driver is cross architecture.

[Tided up to work on x86]
[Ported to 3.4]
[Cleaned up for 3.7 and submission]

---

 drivers/input/keyboard/Kconfig           |   10 ++
 drivers/input/keyboard/Makefile          |    1 
 drivers/input/keyboard/goldfish_events.c |  187 ++++++++++++++++++++++++++++++
 drivers/tty/goldfish.c                   |   19 +--
 4 files changed, 205 insertions(+), 12 deletions(-)
 create mode 100644 drivers/input/keyboard/goldfish_events.c
drivers/input/keyboard/Kconfig +10 -0
index 008f96a..07f7bb2 100644
@@ -482,6 +482,16 @@ config KEYBOARD_SAMSUNG
 	  To compile this driver as a module, choose M here: the
 	  module will be called samsung-keypad.
 
+config KEYBOARD_GOLDFISH_EVENTS
+	depends on GOLDFISH
+	tristate "Generic Input Event device for Goldfish"
+	help
+	  Say Y here to get an input event device for the Goldfish virtual
+	  device emulator.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called goldfish-events.
+
 if TTY
 
 config KEYBOARD_STOWAWAY
drivers/input/keyboard/Makefile +1 -0
index 44e7600..49b1645 100644
@@ -13,6 +13,7 @@ obj-$(CONFIG_KEYBOARD_ATKBD)		+= atkbd.o
 obj-$(CONFIG_KEYBOARD_BFIN)		+= bf54x-keys.o
 obj-$(CONFIG_KEYBOARD_DAVINCI)		+= davinci_keyscan.o
 obj-$(CONFIG_KEYBOARD_EP93XX)		+= ep93xx_keypad.o
+obj-$(CONFIG_KEYBOARD_GOLDFISH_EVENTS)	+= goldfish_events.o
 obj-$(CONFIG_KEYBOARD_GPIO)		+= gpio_keys.o
 obj-$(CONFIG_KEYBOARD_GPIO_POLLED)	+= gpio_keys_polled.o
 obj-$(CONFIG_KEYBOARD_TCA6416)		+= tca6416-keypad.o
drivers/input/keyboard/goldfish_events.c new file +187 -0

187 lines not on this page · raw message

drivers/tty/goldfish.c +7 -12
index e2ccb6d..f17d2e4 100644
@@ -72,23 +72,18 @@ static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
 	unsigned long irq_flags;
 	unsigned char *buf;
 	u32 count;
-	struct tty_struct *tty;
 
 	count = readl(base + GOLDFISH_TTY_BYTES_READY);
 	if(count == 0)
 		return IRQ_NONE;
 
-	tty = tty_port_tty_get(&qtty->port);
-	if (tty) {
-		count = tty_prepare_flip_string(tty, &buf, count);
-		spin_lock_irqsave(&qtty->lock, irq_flags);
-		writel((u32)buf, base + GOLDFISH_TTY_DATA_PTR);
-		writel(count, base + GOLDFISH_TTY_DATA_LEN);
-		writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
-		spin_unlock_irqrestore(&qtty->lock, irq_flags);
-		tty_schedule_flip(tty);
-		tty_kref_put(tty);
-	}
+	count = tty_prepare_flip_string(&qtty->port, &buf, count);
+	spin_lock_irqsave(&qtty->lock, irq_flags);
+	writel((u32)buf, base + GOLDFISH_TTY_DATA_PTR);
+	writel(count, base + GOLDFISH_TTY_DATA_LEN);
+	writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
+	spin_unlock_irqrestore(&qtty->lock, irq_flags);
+	tty_schedule_flip(&qtty->port);
 	return IRQ_HANDLED;
 }
 
maintainer
#1 lore raw

Hi Alan,

Quoted 114 lines · Alan Cox

From: Brian Swetland <[email protected]>

This device is a direct pipe from "hardware" to the input event subsystem, allowing us to avoid having to route "keypad" style events through an AT keyboard driver (gross!)

As with the other submissions this driver is cross architecture.

[Tided up to work on x86]
[Ported to 3.4]
[Cleaned up for 3.7 and submission]

---

 drivers/input/keyboard/Kconfig           |   10 ++
 drivers/input/keyboard/Makefile          |    1 
 drivers/input/keyboard/goldfish_events.c |  187 ++++++++++++++++++++++++++++++
 drivers/tty/goldfish.c                   |   19 +--
 4 files changed, 205 insertions(+), 12 deletions(-)
 create mode 100644 drivers/input/keyboard/goldfish_events.c
drivers/input/keyboard/Kconfig +10 -0
index 008f96a..07f7bb2 100644
@@ -482,6 +482,16 @@ config KEYBOARD_SAMSUNG
 	  To compile this driver as a module, choose M here: the
 	  module will be called samsung-keypad.
 
+config KEYBOARD_GOLDFISH_EVENTS
+	depends on GOLDFISH
+	tristate "Generic Input Event device for Goldfish"
+	help
+	  Say Y here to get an input event device for the Goldfish virtual
+	  device emulator.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called goldfish-events.
+
 if TTY
 
 config KEYBOARD_STOWAWAY
drivers/input/keyboard/Makefile +1 -0
index 44e7600..49b1645 100644
@@ -13,6 +13,7 @@ obj-$(CONFIG_KEYBOARD_ATKBD)		+= atkbd.o
 obj-$(CONFIG_KEYBOARD_BFIN)		+= bf54x-keys.o
 obj-$(CONFIG_KEYBOARD_DAVINCI)		+= davinci_keyscan.o
 obj-$(CONFIG_KEYBOARD_EP93XX)		+= ep93xx_keypad.o
+obj-$(CONFIG_KEYBOARD_GOLDFISH_EVENTS)	+= goldfish_events.o
 obj-$(CONFIG_KEYBOARD_GPIO)		+= gpio_keys.o
 obj-$(CONFIG_KEYBOARD_GPIO_POLLED)	+= gpio_keys_polled.o
 obj-$(CONFIG_KEYBOARD_TCA6416)		+= tca6416-keypad.o
drivers/input/keyboard/goldfish_events.c new file +46 -0
new file mode 100644
index 0000000..8b1f0cd
@@ -0,0 +1,187 @@
+/*
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (C) 2012 Intel, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+enum {
+	REG_READ        = 0x00,
+	REG_SET_PAGE    = 0x00,
+	REG_LEN         = 0x04,
+	REG_DATA        = 0x08,
+
+	PAGE_NAME       = 0x00000,
+	PAGE_EVBITS     = 0x10000,
+	PAGE_ABSDATA    = 0x20000 | EV_ABS,
+};
+
+struct event_dev {
+	struct input_dev *input;
+	int irq;
+	void __iomem *addr;
+	char name[0];
+};
+
+static irqreturn_t events_interrupt(int irq, void *dev_id)
+{

drivers/input/keyboard/goldfish_events.c line 56

Quoted 10 lines
drivers/input/keyboard/goldfish_events.c new file +10 -0
+	struct event_dev *edev = dev_id;
+	unsigned type, code, value;
+
+	type = __raw_readl(edev->addr + REG_READ);
+	code = __raw_readl(edev->addr + REG_READ);
+	value = __raw_readl(edev->addr + REG_READ);
+
+	input_event(edev->input, type, code, value);
+	if (type == EV_KEY)
+		input_sync(edev->input);

Why do we send sync only for EV_KEY?

Quoted 31 lines
drivers/input/keyboard/goldfish_events.c new file +31 -0
+	return IRQ_HANDLED;
+}
+
+static void events_import_bits(struct event_dev *edev,
+			unsigned long bits[], unsigned type, size_t count)
+{
+	int i, j;
+	size_t size;
+	uint8_t val;
+	void __iomem *addr = edev->addr;
+	__raw_writel(PAGE_EVBITS | type, addr + REG_SET_PAGE);
+	size = __raw_readl(addr + REG_LEN) * 8;
+	if (size < count)
+		count = size;
+	addr = addr + REG_DATA;
+	for (i = 0; i < count; i += 8) {
+		val = __raw_readb(addr++);
+		for (j = 0; j < 8; j++)
+			if (val & 1 << j)
+				set_bit(i + j, bits);
+	}
+}
+
+static int events_probe(struct platform_device *pdev)
+{
+	struct input_dev *input_dev;
+	struct event_dev *edev = NULL;
+	struct resource *res;
+	unsigned keymapnamelen;
+	int i;
+	int count;

drivers/input/keyboard/goldfish_events.c line 97

Quoted 10 lines
drivers/input/keyboard/goldfish_events.c new file +10 -0
+	int irq;
+	void __iomem *addr;
+	int ret;
+
+	input_dev = input_allocate_device();
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!input_dev || !res)
+		goto fail;
+
+	addr = devm_ioremap(&pdev->dev, res->start, 4096);

No need to reserve region? And why hardcoding the length?

Quoted 64 lines
drivers/input/keyboard/goldfish_events.c new file +64 -0
+	irq = platform_get_irq(pdev, 0);
+
+	if (!addr || irq < 0)
+		goto fail;
+
+	__raw_writel(PAGE_NAME, addr + REG_SET_PAGE);
+	keymapnamelen = __raw_readl(addr + REG_LEN);
+
+	edev = devm_kzalloc(&pdev->dev, sizeof(struct event_dev) + keymapnamelen + 1,
+								GFP_KERNEL);
+	if (!edev)
+		goto fail;
+
+	edev->input = input_dev;
+	edev->addr = addr;
+	edev->irq = irq;
+
+	for (i = 0; i < keymapnamelen; i++)
+		edev->name[i] = __raw_readb(edev->addr + REG_DATA + i);
+
+	pr_debug("events_probe() keymap=%s\n", edev->name);
+
+	events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX);
+	events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX);
+	events_import_bits(edev, input_dev->relbit, EV_REL, REL_MAX);
+	events_import_bits(edev, input_dev->absbit, EV_ABS, ABS_MAX);
+	events_import_bits(edev, input_dev->mscbit, EV_MSC, MSC_MAX);
+	events_import_bits(edev, input_dev->ledbit, EV_LED, LED_MAX);
+	events_import_bits(edev, input_dev->sndbit, EV_SND, SND_MAX);
+	events_import_bits(edev, input_dev->ffbit, EV_FF, FF_MAX);
+	events_import_bits(edev, input_dev->swbit, EV_SW, SW_MAX);
+
+	__raw_writel(PAGE_ABSDATA, addr + REG_SET_PAGE);
+	count = __raw_readl(addr + REG_LEN) / (4 * 4);
+	if (count > ABS_MAX)
+		count = ABS_MAX;
+	for (i = 0; i < count; i++) {
+		int val[4];
+		int j;
+		if (!test_bit(i, input_dev->absbit))
+			continue;
+		for (j = 0; j < ARRAY_SIZE(val); j++)
+			val[j] = __raw_readl(edev->addr + REG_DATA + (i * ARRAY_SIZE(val) + j) * 4);
+		input_set_abs_params(input_dev, i, val[0], val[1],
+							val[2], val[3]);
+	}
+
+	platform_set_drvdata(pdev, edev);
+
+	input_dev->name = edev->name;
+	input_set_drvdata(input_dev, edev);
+
+	ret = input_register_device(input_dev);
+	if (ret)
+		goto fail;
+
+	if (devm_request_irq(&pdev->dev, edev->irq, events_interrupt, 0,
+				"goldfish-events-keypad", edev) < 0) {
+		input_unregister_device(input_dev);
+		return -EINVAL;
+	}
+
+	return 0;
+

drivers/input/keyboard/goldfish_events.c line 171

Quoted 10 lines
drivers/input/keyboard/goldfish_events.c new file +10 -0
+fail:
+	input_free_device(input_dev);
+	return -EINVAL;
+}
+
+static int events_remove(struct platform_device *pdev)
+{
+	struct event_dev *edev = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = edev->input;
+	input_unregister_device(input_dev);

This will explode if interrupt arrives here. We now have devm_input_allocate_device(), please switch to using it and then we can get rid of events_remove() completely.

drivers/input/keyboard/goldfish_events.c line 179

Quoted 8 lines
drivers/input/keyboard/goldfish_events.c new file +8 -0
+	return 0;
+}
+
+static struct platform_driver events_driver = {
+	.probe = events_probe,
+	.remove = events_remove,
+	.driver = {
+		.name = "goldfish_events",

.owner = THIS_MODULE,

Thanks.

Signature · 1 line
Dmitry