| /* |
| * Driver for buttons on GPIO lines not capable of generating interrupts |
| * |
| * Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org> |
| * Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com> |
| * |
| * This file was based on: /drivers/input/misc/cobalt_btns.c |
| * Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> |
| * |
| * also was based on: /drivers/input/keyboard/gpio_keys.c |
| * Copyright 2005 Phil Blundell |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include <linux/slab.h> |
| #include <linux/input.h> |
| #include <linux/input-polldev.h> |
| #include <linux/ioport.h> |
| #include <linux/platform_device.h> |
| #include <linux/gpio.h> |
| #include <linux/gpio_keys.h> |
| #include <linux/of_platform.h> |
| #include <linux/of_gpio.h> |
| |
| #define DRV_NAME "gpio-keys-polled" |
| |
| struct gpio_keys_button_data { |
| int last_state; |
| int count; |
| int threshold; |
| int can_sleep; |
| }; |
| |
| struct gpio_keys_polled_dev { |
| struct input_polled_dev *poll_dev; |
| struct device *dev; |
| const struct gpio_keys_platform_data *pdata; |
| struct gpio_keys_button_data data[0]; |
| }; |
| |
| static void gpio_keys_polled_check_state(struct input_dev *input, |
| struct gpio_keys_button *button, |
| struct gpio_keys_button_data *bdata) |
| { |
| int state; |
| |
| if (bdata->can_sleep) |
| state = !!gpio_get_value_cansleep(button->gpio); |
| else |
| state = !!gpio_get_value(button->gpio); |
| |
| if (state != bdata->last_state) { |
| unsigned int type = button->type ?: EV_KEY; |
| |
| input_event(input, type, button->code, |
| !!(state ^ button->active_low)); |
| input_sync(input); |
| bdata->count = 0; |
| bdata->last_state = state; |
| } |
| } |
| |
| static void gpio_keys_polled_poll(struct input_polled_dev *dev) |
| { |
| struct gpio_keys_polled_dev *bdev = dev->private; |
| const struct gpio_keys_platform_data *pdata = bdev->pdata; |
| struct input_dev *input = dev->input; |
| int i; |
| |
| for (i = 0; i < pdata->nbuttons; i++) { |
| struct gpio_keys_button_data *bdata = &bdev->data[i]; |
| |
| if (bdata->count < bdata->threshold) |
| bdata->count++; |
| else |
| gpio_keys_polled_check_state(input, &pdata->buttons[i], |
| bdata); |
| } |
| } |
| |
| static void gpio_keys_polled_open(struct input_polled_dev *dev) |
| { |
| struct gpio_keys_polled_dev *bdev = dev->private; |
| const struct gpio_keys_platform_data *pdata = bdev->pdata; |
| |
| if (pdata->enable) |
| pdata->enable(bdev->dev); |
| } |
| |
| static void gpio_keys_polled_close(struct input_polled_dev *dev) |
| { |
| struct gpio_keys_polled_dev *bdev = dev->private; |
| const struct gpio_keys_platform_data *pdata = bdev->pdata; |
| |
| if (pdata->disable) |
| pdata->disable(bdev->dev); |
| } |
| |
| #ifdef CONFIG_OF |
| static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct device *dev) |
| { |
| struct device_node *node, *pp; |
| struct gpio_keys_platform_data *pdata; |
| struct gpio_keys_button *button; |
| int error; |
| int nbuttons; |
| int i; |
| |
| node = dev->of_node; |
| if (!node) |
| return NULL; |
| |
| nbuttons = of_get_child_count(node); |
| if (nbuttons == 0) |
| return NULL; |
| |
| pdata = kzalloc(sizeof(*pdata) + nbuttons * (sizeof *button), |
| GFP_KERNEL); |
| if (!pdata) { |
| error = -ENOMEM; |
| goto err_out; |
| } |
| |
| pdata->buttons = (struct gpio_keys_button *)(pdata + 1); |
| pdata->nbuttons = nbuttons; |
| |
| pdata->rep = !!of_get_property(node, "autorepeat", NULL); |
| of_property_read_u32(node, "poll-interval", &pdata->poll_interval); |
| |
| i = 0; |
| for_each_child_of_node(node, pp) { |
| enum of_gpio_flags flags; |
| |
| if (!of_find_property(pp, "gpios", NULL)) { |
| pdata->nbuttons--; |
| dev_warn(dev, "Found button without gpios\n"); |
| continue; |
| } |
| |
| button = &pdata->buttons[i++]; |
| |
| button->gpio = of_get_gpio_flags(pp, 0, &flags); |
| button->active_low = flags & OF_GPIO_ACTIVE_LOW; |
| |
| if (of_property_read_u32(pp, "linux,code", &button->code)) { |
| dev_err(dev, "Button without keycode: 0x%x\n", |
| button->gpio); |
| error = -EINVAL; |
| goto err_free_pdata; |
| } |
| |
| button->desc = of_get_property(pp, "label", NULL); |
| |
| if (of_property_read_u32(pp, "linux,input-type", &button->type)) |
| button->type = EV_KEY; |
| |
| button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL); |
| |
| if (of_property_read_u32(pp, "debounce-interval", |
| &button->debounce_interval)) |
| button->debounce_interval = 5; |
| } |
| |
| if (pdata->nbuttons == 0) { |
| error = -EINVAL; |
| goto err_free_pdata; |
| } |
| |
| return pdata; |
| |
| err_free_pdata: |
| kfree(pdata); |
| err_out: |
| return ERR_PTR(error); |
| } |
| |
| static struct of_device_id gpio_keys_polled_of_match[] = { |
| { .compatible = "gpio-keys-polled", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match); |
| |
| #else |
| |
| static inline struct gpio_keys_platform_data * |
| gpio_keys_polled_get_devtree_pdata(struct device *dev) |
| { |
| return NULL; |
| } |
| #endif |
| |
| static int gpio_keys_polled_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev); |
| struct gpio_keys_polled_dev *bdev; |
| struct input_polled_dev *poll_dev; |
| struct input_dev *input; |
| int error; |
| int i; |
| |
| if (!pdata) { |
| pdata = gpio_keys_polled_get_devtree_pdata(dev); |
| if (IS_ERR(pdata)) |
| return PTR_ERR(pdata); |
| if (!pdata) { |
| dev_err(dev, "missing platform data\n"); |
| return -EINVAL; |
| } |
| } |
| |
| if (!pdata->poll_interval) { |
| dev_err(dev, "missing poll_interval value\n"); |
| error = -EINVAL; |
| goto err_free_pdata; |
| } |
| |
| bdev = kzalloc(sizeof(struct gpio_keys_polled_dev) + |
| pdata->nbuttons * sizeof(struct gpio_keys_button_data), |
| GFP_KERNEL); |
| if (!bdev) { |
| dev_err(dev, "no memory for private data\n"); |
| error = -ENOMEM; |
| goto err_free_pdata; |
| } |
| |
| poll_dev = input_allocate_polled_device(); |
| if (!poll_dev) { |
| dev_err(dev, "no memory for polled device\n"); |
| error = -ENOMEM; |
| goto err_free_bdev; |
| } |
| |
| poll_dev->private = bdev; |
| poll_dev->poll = gpio_keys_polled_poll; |
| poll_dev->poll_interval = pdata->poll_interval; |
| poll_dev->open = gpio_keys_polled_open; |
| poll_dev->close = gpio_keys_polled_close; |
| |
| input = poll_dev->input; |
| |
| input->evbit[0] = BIT(EV_KEY); |
| input->name = pdev->name; |
| input->phys = DRV_NAME"/input0"; |
| input->dev.parent = &pdev->dev; |
| |
| input->id.bustype = BUS_HOST; |
| input->id.vendor = 0x0001; |
| input->id.product = 0x0001; |
| input->id.version = 0x0100; |
| |
| for (i = 0; i < pdata->nbuttons; i++) { |
| struct gpio_keys_button *button = &pdata->buttons[i]; |
| struct gpio_keys_button_data *bdata = &bdev->data[i]; |
| unsigned int gpio = button->gpio; |
| unsigned int type = button->type ?: EV_KEY; |
| |
| if (button->wakeup) { |
| dev_err(dev, DRV_NAME " does not support wakeup\n"); |
| error = -EINVAL; |
| goto err_free_gpio; |
| } |
| |
| error = gpio_request(gpio, |
| button->desc ? button->desc : DRV_NAME); |
| if (error) { |
| dev_err(dev, "unable to claim gpio %u, err=%d\n", |
| gpio, error); |
| goto err_free_gpio; |
| } |
| |
| error = gpio_direction_input(gpio); |
| if (error) { |
| dev_err(dev, |
| "unable to set direction on gpio %u, err=%d\n", |
| gpio, error); |
| goto err_free_gpio; |
| } |
| |
| bdata->can_sleep = gpio_cansleep(gpio); |
| bdata->last_state = -1; |
| bdata->threshold = DIV_ROUND_UP(button->debounce_interval, |
| pdata->poll_interval); |
| |
| input_set_capability(input, type, button->code); |
| } |
| |
| bdev->poll_dev = poll_dev; |
| bdev->dev = dev; |
| bdev->pdata = pdata; |
| platform_set_drvdata(pdev, bdev); |
| |
| error = input_register_polled_device(poll_dev); |
| if (error) { |
| dev_err(dev, "unable to register polled device, err=%d\n", |
| error); |
| goto err_free_gpio; |
| } |
| |
| /* report initial state of the buttons */ |
| for (i = 0; i < pdata->nbuttons; i++) |
| gpio_keys_polled_check_state(input, &pdata->buttons[i], |
| &bdev->data[i]); |
| |
| return 0; |
| |
| err_free_gpio: |
| while (--i >= 0) |
| gpio_free(pdata->buttons[i].gpio); |
| |
| input_free_polled_device(poll_dev); |
| |
| err_free_bdev: |
| kfree(bdev); |
| platform_set_drvdata(pdev, NULL); |
| |
| err_free_pdata: |
| /* If we have no platform_data, we allocated pdata dynamically. */ |
| if (!dev_get_platdata(&pdev->dev)) |
| kfree(pdata); |
| |
| return error; |
| } |
| |
| static int __devexit gpio_keys_polled_remove(struct platform_device *pdev) |
| { |
| struct gpio_keys_polled_dev *bdev = platform_get_drvdata(pdev); |
| const struct gpio_keys_platform_data *pdata = bdev->pdata; |
| int i; |
| |
| input_unregister_polled_device(bdev->poll_dev); |
| |
| for (i = 0; i < pdata->nbuttons; i++) |
| gpio_free(pdata->buttons[i].gpio); |
| |
| input_free_polled_device(bdev->poll_dev); |
| |
| /* |
| * If we had no platform_data, we allocated pdata dynamically and |
| * must free it here. |
| */ |
| if (!dev_get_platdata(&pdev->dev)) |
| kfree(pdata); |
| |
| kfree(bdev); |
| platform_set_drvdata(pdev, NULL); |
| |
| return 0; |
| } |
| |
| static struct platform_driver gpio_keys_polled_driver = { |
| .probe = gpio_keys_polled_probe, |
| .remove = gpio_keys_polled_remove, |
| .driver = { |
| .name = DRV_NAME, |
| .owner = THIS_MODULE, |
| .of_match_table = of_match_ptr(gpio_keys_polled_of_match), |
| }, |
| }; |
| module_platform_driver(gpio_keys_polled_driver); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>"); |
| MODULE_DESCRIPTION("Polled GPIO Buttons driver"); |
| MODULE_ALIAS("platform:" DRV_NAME); |