5 files changed, 137 insertions, 18 deletions

diff --git a/arch/mips/include/asm/mach-rc32434/gpio.h b/arch/mips/include/asm/mach-rc32434/gpio.h
index 3cb50d17b62d..12ee8d510160 100644
--- a/arch/mips/include/asm/mach-rc32434/gpio.h
+++ b/arch/mips/include/asm/mach-rc32434/gpio.h
@@ -80,6 +80,9 @@ struct rb532_gpio_reg {
 /* Compact Flash GPIO pin */
 #define CF_GPIO_NUM             13
 
+/* S1 button GPIO (shared with UART0_SIN) */
+#define GPIO_BTN_S1             1
+
 extern void rb532_gpio_set_ilevel(int bit, unsigned gpio);
 extern void rb532_gpio_set_istat(int bit, unsigned gpio);
 extern void rb532_gpio_set_func(unsigned gpio);
diff --git a/arch/mips/rb532/devices.c b/arch/mips/rb532/devices.c
index 4a5f05b662ae..9f40e1ff9b4f 100644
--- a/arch/mips/rb532/devices.c
+++ b/arch/mips/rb532/devices.c
@@ -200,26 +200,9 @@ static struct platform_device rb532_led = {
         .id = -1,
 };
 
-static struct gpio_keys_button rb532_gpio_btn[] = {
-        {
-                .gpio = 1,
-                .code = BTN_0,
-                .desc = "S1",
-                .active_low = 1,
-        }
-};
-
-static struct gpio_keys_platform_data rb532_gpio_btn_data = {
-        .buttons = rb532_gpio_btn,
-        .nbuttons = ARRAY_SIZE(rb532_gpio_btn),
-};
-
 static struct platform_device rb532_button = {
-        .name   = "gpio-keys",
+        .name   = "rb532-button",
         .id     = -1,
-        .dev    = {
-                .platform_data = &rb532_gpio_btn_data,
-        }
 };
 
 static struct resource rb532_wdt_res[] = {
diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 806d2e66d249..203abac1e23e 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -238,4 +238,16 @@ config INPUT_GPIO_ROTARY_ENCODER
           To compile this driver as a module, choose M here: the
           module will be called rotary_encoder.
 
+config INPUT_RB532_BUTTON
+        tristate "Mikrotik Routerboard 532 button interface"
+        depends on MIKROTIK_RB532
+        depends on GPIOLIB && GENERIC_GPIO
+        select INPUT_POLLDEV
+        help
+          Say Y here if you want support for the S1 button built into
+          Mikrotik's Routerboard 532.
+
+          To compile this driver as a module, choose M here: the
+          module will be called rb532_button.
+
 endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index e86cee66c914..e94cfd9be6cc 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -23,4 +23,5 @@ obj-$(CONFIG_INPUT_APANEL)		+= apanel.o
 obj-$(CONFIG_INPUT_SGI_BTNS)            += sgi_btns.o
 obj-$(CONFIG_INPUT_PCF50633_PMU)        += pcf50633-input.o
 obj-$(CONFIG_INPUT_GPIO_ROTARY_ENCODER) += rotary_encoder.o
+obj-$(CONFIG_INPUT_RB532_BUTTON)        += rb532_button.o
 
diff --git a/drivers/input/misc/rb532_button.c b/drivers/input/misc/rb532_button.c
new file mode 100644
index 000000000000..e2c7f622a0b5
--- /dev/null
+++ b/drivers/input/misc/rb532_button.c
@@ -0,0 +1,120 @@
+/*
+ * Support for the S1 button on Routerboard 532
+ *
+ * Copyright (C) 2009  Phil Sutter <n0-1@freewrt.org>
+ */
+
+#include <linux/input-polldev.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <asm/mach-rc32434/gpio.h>
+#include <asm/mach-rc32434/rb.h>
+
+#define DRV_NAME "rb532-button"
+
+#define RB532_BTN_RATE 100 /* msec */
+#define RB532_BTN_KSYM BTN_0
+
+/* The S1 button state is provided by GPIO pin 1. But as this
+ * pin is also used for uart input as alternate function, the
+ * operational modes must be switched first:
+ * 1) disable uart using set_latch_u5()
+ * 2) turn off alternate function implicitly through
+ *    gpio_direction_input()
+ * 3) read the GPIO's current value
+ * 4) undo step 2 by enabling alternate function (in this
+ *    mode the GPIO direction is fixed, so no change needed)
+ * 5) turn on uart again
+ * The GPIO value occurs to be inverted, so pin high means
+ * button is not pressed.
+ */
+static bool rb532_button_pressed(void)
+{
+        int val;
+
+        set_latch_u5(0, LO_FOFF);
+        gpio_direction_input(GPIO_BTN_S1);
+
+        val = gpio_get_value(GPIO_BTN_S1);
+
+        rb532_gpio_set_func(GPIO_BTN_S1);
+        set_latch_u5(LO_FOFF, 0);
+
+        return !val;
+}
+
+static void rb532_button_poll(struct input_polled_dev *poll_dev)
+{
+        input_report_key(poll_dev->input, RB532_BTN_KSYM,
+                         rb532_button_pressed());
+        input_sync(poll_dev->input);
+}
+
+static int __devinit rb532_button_probe(struct platform_device *pdev)
+{
+        struct input_polled_dev *poll_dev;
+        int error;
+
+        poll_dev = input_allocate_polled_device();
+        if (!poll_dev)
+                return -ENOMEM;
+
+        poll_dev->poll = rb532_button_poll;
+        poll_dev->poll_interval = RB532_BTN_RATE;
+
+        poll_dev->input->name = "rb532 button";
+        poll_dev->input->phys = "rb532/button0";
+        poll_dev->input->id.bustype = BUS_HOST;
+        poll_dev->input->dev.parent = &pdev->dev;
+
+        dev_set_drvdata(&pdev->dev, poll_dev);
+
+        input_set_capability(poll_dev->input, EV_KEY, RB532_BTN_KSYM);
+
+        error = input_register_polled_device(poll_dev);
+        if (error) {
+                input_free_polled_device(poll_dev);
+                return error;
+        }
+
+        return 0;
+}
+
+static int __devexit rb532_button_remove(struct platform_device *pdev)
+{
+        struct input_polled_dev *poll_dev = dev_get_drvdata(&pdev->dev);
+
+        input_unregister_polled_device(poll_dev);
+        input_free_polled_device(poll_dev);
+        dev_set_drvdata(&pdev->dev, NULL);
+
+        return 0;
+}
+
+static struct platform_driver rb532_button_driver = {
+        .probe = rb532_button_probe,
+        .remove = __devexit_p(rb532_button_remove),
+        .driver = {
+                .name = DRV_NAME,
+                .owner = THIS_MODULE,
+        },
+};
+
+static int __init rb532_button_init(void)
+{
+        return platform_driver_register(&rb532_button_driver);
+}
+
+static void __exit rb532_button_exit(void)
+{
+        platform_driver_unregister(&rb532_button_driver);
+}
+
+module_init(rb532_button_init);
+module_exit(rb532_button_exit);
+
+MODULE_AUTHOR("Phil Sutter <n0-1@freewrt.org>");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Support for S1 button on Routerboard 532");
+MODULE_ALIAS("platform:" DRV_NAME);