diff options
author | Ingo Molnar <mingo@elte.hu> | 2009-06-07 12:22:15 +0200 |
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committer | Ingo Molnar <mingo@elte.hu> | 2009-06-07 12:22:15 +0200 |
commit | 5f4457a4f62cc9d78e04c0eb12ff0540899aad89 (patch) | |
tree | 0b973d527ea6b2ae31e08da0746b4965a3c5a6d8 /drivers/input/misc/rb532_button.c | |
parent | 9b94b3a19b13e094c10f65f24bc358f6ffe4eacd (diff) | |
parent | b87297fb405ef13cac375f202d114323b076a56d (diff) |
Merge branch 'linus' into x86/cpu
Diffstat (limited to 'drivers/input/misc/rb532_button.c')
-rw-r--r-- | drivers/input/misc/rb532_button.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/input/misc/rb532_button.c b/drivers/input/misc/rb532_button.c new file mode 100644 index 00000000000..e2c7f622a0b --- /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); |