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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/input/misc/rb532_button.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/input/misc/rb532_button.c')
-rw-r--r-- | drivers/input/misc/rb532_button.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/input/misc/rb532_button.c b/drivers/input/misc/rb532_button.c new file mode 100644 index 000000000..190a80e1e --- /dev/null +++ b/drivers/input/misc/rb532_button.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Support for the S1 button on Routerboard 532 + * + * Copyright (C) 2009 Phil Sutter <n0-1@freewrt.org> + */ + +#include <linux/input.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/gpio.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_dev *input) +{ + input_report_key(input, RB532_BTN_KSYM, rb532_button_pressed()); + input_sync(input); +} + +static int rb532_button_probe(struct platform_device *pdev) +{ + struct input_dev *input; + int error; + + input = devm_input_allocate_device(&pdev->dev); + if (!input) + return -ENOMEM; + + input->name = "rb532 button"; + input->phys = "rb532/button0"; + input->id.bustype = BUS_HOST; + + input_set_capability(input, EV_KEY, RB532_BTN_KSYM); + + error = input_setup_polling(input, rb532_button_poll); + if (error) + return error; + + input_set_poll_interval(input, RB532_BTN_RATE); + + error = input_register_device(input); + if (error) + return error; + + return 0; +} + +static struct platform_driver rb532_button_driver = { + .probe = rb532_button_probe, + .driver = { + .name = DRV_NAME, + }, +}; +module_platform_driver(rb532_button_driver); + +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); |