[PATCH 1/4 v2] add gpio keyboard support
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Thu Feb 16 05:20:24 EST 2012
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
V2:
use kfifo
Best regards,
J.
drivers/Kconfig | 1 +
drivers/Makefile | 1 +
drivers/input/Kconfig | 19 +++++++
drivers/input/Makefile | 1 +
drivers/input/gpio_keys.c | 115 +++++++++++++++++++++++++++++++++++++++++++++
include/driver.h | 5 ++
include/gpio_keys.h | 30 ++++++++++++
7 files changed, 172 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/Kconfig
create mode 100644 drivers/input/Makefile
create mode 100644 drivers/input/gpio_keys.c
create mode 100644 include/gpio_keys.h
diff --git a/drivers/Kconfig b/drivers/Kconfig
index c4e1517..c058b25 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -14,5 +14,6 @@ source "drivers/clk/Kconfig"
source "drivers/mfd/Kconfig"
source "drivers/led/Kconfig"
source "drivers/eeprom/Kconfig"
+source "drivers/input/Kconfig"
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 592c39e..61e85af 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -13,3 +13,4 @@ obj-y += clk/
obj-y += mfd/
obj-$(CONFIG_LED) += led/
obj-y += eeprom/
+obj-y += input/
diff --git a/drivers/input/Kconfig b/drivers/input/Kconfig
new file mode 100644
index 0000000..b488553
--- /dev/null
+++ b/drivers/input/Kconfig
@@ -0,0 +1,19 @@
+#
+# Input device configuration
+#
+
+menu "Input device support"
+
+config KEYBOARD_GPIO
+ bool "GPIO Buttons"
+ depends on GENERIC_GPIO
+ help
+ This driver implements support for buttons connected
+ to GPIO pins of various CPUs (and some other chips).
+
+ Say Y here if your device has buttons connected
+ directly to such GPIO pins. Your board-specific
+ setup logic must also provide a platform device,
+ with configuration data saying which GPIOs are used.
+
+endmenu
diff --git a/drivers/input/Makefile b/drivers/input/Makefile
new file mode 100644
index 0000000..7784d52
--- /dev/null
+++ b/drivers/input/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_KEYBOARD_GPIO) += gpio_keys.o
diff --git a/drivers/input/gpio_keys.c b/drivers/input/gpio_keys.c
new file mode 100644
index 0000000..4d0f6ab
--- /dev/null
+++ b/drivers/input/gpio_keys.c
@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
+ *
+ * Under GPLv2
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <init.h>
+#include <clock.h>
+#include <gpio_keys.h>
+#include <poller.h>
+#include <gpio.h>
+
+static inline struct gpio_keys_platform_data *
+poller_to_gk_pdata(struct poller_struct *poller)
+{
+ return container_of(poller, struct gpio_keys_platform_data, poller);
+}
+
+static inline struct gpio_keys_platform_data *
+cdev_to_gk_pdata(struct console_device *cdev)
+{
+ return container_of(cdev, struct gpio_keys_platform_data, cdev);
+}
+
+static void gpio_key_poller(struct poller_struct *poller)
+{
+ struct gpio_keys_platform_data *pdata = poller_to_gk_pdata(poller);
+ struct gpio_keys_button *gb;
+ int i, val;
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+
+ gb = &pdata->buttons[i];
+ val = gpio_get_value(gb->gpio);
+
+ if (val != gb->previous_state && val != gb->active_low) {
+ kfifo_put(pdata->recv_fifo, (u_char*)&gb->code, sizeof(int));
+ debug("pressed gpio(%d) as %d\n", gb->gpio, gb->code);
+ }
+ gb->previous_state = val;
+ }
+}
+
+static int gpio_keys_tstc(struct console_device *cdev)
+{
+ struct gpio_keys_platform_data *pdata = cdev_to_gk_pdata(cdev);
+
+ return (kfifo_len(pdata->recv_fifo) == 0) ? 0 : 1;
+}
+
+static int gpio_keys_getc(struct console_device *cdev)
+{
+ int code = 0;
+ struct gpio_keys_platform_data *pdata = cdev_to_gk_pdata(cdev);
+
+ kfifo_get(pdata->recv_fifo, (u_char*)&code, sizeof(int));
+ return code;
+}
+
+static int __init gpio_keys_probe(struct device_d *dev)
+{
+ int ret, i, gpio;
+ struct gpio_keys_platform_data *pdata;
+ struct console_device *cdev;
+
+ pdata = dev->platform_data;
+
+ if (!pdata) {
+ /* small (so we copy it) but critical! */
+ pr_err("missing platform_data\n");
+ return -ENODEV;
+ }
+
+ if (!pdata->fifo_size)
+ pdata->fifo_size = 50;
+
+ pdata->recv_fifo = kfifo_alloc(pdata->fifo_size);
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+ gpio = pdata->buttons->gpio;
+ ret = gpio_request(gpio, "gpio_keys");
+ if (ret) {
+ pr_err("gpio_keys: (%d) can not be requested\n", gpio);
+ return ret;
+ }
+ gpio_direction_input(gpio);
+ }
+
+ pdata->poller.func = gpio_key_poller;
+
+ cdev = &pdata->cdev;
+ dev->type_data = cdev;
+ cdev->dev = dev;
+ cdev->f_caps = CONSOLE_STDIN;
+ cdev->tstc = gpio_keys_tstc;
+ cdev->getc = gpio_keys_getc;
+
+ console_register(&pdata->cdev);
+
+ return poller_register(&pdata->poller);
+}
+
+static struct driver_d gpio_keys_driver = {
+ .name = "gpio_keys",
+ .probe = gpio_keys_probe,
+};
+
+static int gpio_keys_init(void)
+{
+ register_driver(&gpio_keys_driver);
+ return 0;
+}
+device_initcall(gpio_keys_init);
diff --git a/include/driver.h b/include/driver.h
index 1b8b16d..51d6393 100644
--- a/include/driver.h
+++ b/include/driver.h
@@ -260,6 +260,11 @@ static inline struct device_d *add_generic_usb_ehci_device(int id,
return add_usb_ehci_device(id, base + 0x100, base + 0x140, pdata);
}
+static inline struct device_d *add_gpio_keys_device(int id, void *pdata)
+{
+ return add_generic_device_res("gpio_keys", id, 0, 0, pdata);
+}
+
/* linear list over all available devices
*/
extern struct list_head device_list;
diff --git a/include/gpio_keys.h b/include/gpio_keys.h
new file mode 100644
index 0000000..fc548fa
--- /dev/null
+++ b/include/gpio_keys.h
@@ -0,0 +1,30 @@
+#ifndef _GPIO_KEYS_H
+#define _GPIO_KEYS_H
+
+#include <poller.h>
+#include <kfifo.h>
+
+struct gpio_keys_button {
+ /* Configuration parameters */
+ int code;
+
+ int gpio;
+ int active_low;
+
+ /* internal */
+ int previous_state;
+};
+
+struct gpio_keys_platform_data {
+ struct gpio_keys_button *buttons;
+ int nbuttons;
+
+ /* optional */
+ int fifo_size;
+
+ struct kfifo *recv_fifo;
+ struct poller_struct poller;
+ struct console_device cdev;
+};
+
+#endif
--
1.7.7
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