![Linus Torvalds](/assets/img/avatar_default.png)
Pull input layer fix from Dmitry Torokhov: "A small fixup to gpio_keys_polled driver" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: gpio_keys_polled - request GPIO pin as input.
309 lines
7.8 KiB
C
309 lines
7.8 KiB
C
/*
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* Driver for buttons on GPIO lines not capable of generating interrupts
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*
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* Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
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* Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
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*
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* This file was based on: /drivers/input/misc/cobalt_btns.c
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* Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
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*
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* also was based on: /drivers/input/keyboard/gpio_keys.c
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* Copyright 2005 Phil Blundell
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/input.h>
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#include <linux/input-polldev.h>
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#include <linux/ioport.h>
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#include <linux/platform_device.h>
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#include <linux/gpio.h>
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#include <linux/gpio/consumer.h>
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#include <linux/gpio_keys.h>
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#include <linux/property.h>
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#define DRV_NAME "gpio-keys-polled"
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struct gpio_keys_button_data {
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int last_state;
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int count;
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int threshold;
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int can_sleep;
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};
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struct gpio_keys_polled_dev {
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struct input_polled_dev *poll_dev;
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struct device *dev;
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const struct gpio_keys_platform_data *pdata;
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struct gpio_keys_button_data data[0];
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};
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static void gpio_keys_polled_check_state(struct input_dev *input,
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struct gpio_keys_button *button,
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struct gpio_keys_button_data *bdata)
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{
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int state;
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if (bdata->can_sleep)
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state = !!gpiod_get_value_cansleep(button->gpiod);
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else
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state = !!gpiod_get_value(button->gpiod);
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if (state != bdata->last_state) {
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unsigned int type = button->type ?: EV_KEY;
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input_event(input, type, button->code, state);
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input_sync(input);
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bdata->count = 0;
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bdata->last_state = state;
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}
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}
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static void gpio_keys_polled_poll(struct input_polled_dev *dev)
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{
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struct gpio_keys_polled_dev *bdev = dev->private;
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const struct gpio_keys_platform_data *pdata = bdev->pdata;
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struct input_dev *input = dev->input;
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int i;
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for (i = 0; i < pdata->nbuttons; i++) {
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struct gpio_keys_button_data *bdata = &bdev->data[i];
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if (bdata->count < bdata->threshold)
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bdata->count++;
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else
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gpio_keys_polled_check_state(input, &pdata->buttons[i],
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bdata);
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}
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}
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static void gpio_keys_polled_open(struct input_polled_dev *dev)
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{
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struct gpio_keys_polled_dev *bdev = dev->private;
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const struct gpio_keys_platform_data *pdata = bdev->pdata;
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if (pdata->enable)
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pdata->enable(bdev->dev);
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}
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static void gpio_keys_polled_close(struct input_polled_dev *dev)
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{
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struct gpio_keys_polled_dev *bdev = dev->private;
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const struct gpio_keys_platform_data *pdata = bdev->pdata;
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if (pdata->disable)
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pdata->disable(bdev->dev);
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}
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static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct device *dev)
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{
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struct gpio_keys_platform_data *pdata;
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struct gpio_keys_button *button;
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struct fwnode_handle *child;
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int error;
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int nbuttons;
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nbuttons = device_get_child_node_count(dev);
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if (nbuttons == 0)
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return NULL;
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pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * sizeof(*button),
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GFP_KERNEL);
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if (!pdata)
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return ERR_PTR(-ENOMEM);
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pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
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pdata->rep = device_property_present(dev, "autorepeat");
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device_property_read_u32(dev, "poll-interval", &pdata->poll_interval);
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device_for_each_child_node(dev, child) {
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struct gpio_desc *desc;
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desc = devm_get_gpiod_from_child(dev, NULL, child);
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if (IS_ERR(desc)) {
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error = PTR_ERR(desc);
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if (error != -EPROBE_DEFER)
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dev_err(dev,
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"Failed to get gpio flags, error: %d\n",
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error);
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fwnode_handle_put(child);
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return ERR_PTR(error);
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}
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button = &pdata->buttons[pdata->nbuttons++];
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button->gpiod = desc;
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if (fwnode_property_read_u32(child, "linux,code", &button->code)) {
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dev_err(dev, "Button without keycode: %d\n",
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pdata->nbuttons - 1);
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fwnode_handle_put(child);
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return ERR_PTR(-EINVAL);
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}
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fwnode_property_read_string(child, "label", &button->desc);
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if (fwnode_property_read_u32(child, "linux,input-type",
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&button->type))
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button->type = EV_KEY;
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button->wakeup = fwnode_property_present(child, "gpio-key,wakeup");
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if (fwnode_property_read_u32(child, "debounce-interval",
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&button->debounce_interval))
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button->debounce_interval = 5;
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}
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if (pdata->nbuttons == 0)
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return ERR_PTR(-EINVAL);
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return pdata;
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}
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static const struct of_device_id gpio_keys_polled_of_match[] = {
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{ .compatible = "gpio-keys-polled", },
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{ },
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};
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MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
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static int gpio_keys_polled_probe(struct platform_device *pdev)
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{
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struct device *dev = &pdev->dev;
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const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
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struct gpio_keys_polled_dev *bdev;
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struct input_polled_dev *poll_dev;
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struct input_dev *input;
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size_t size;
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int error;
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int i;
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if (!pdata) {
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pdata = gpio_keys_polled_get_devtree_pdata(dev);
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if (IS_ERR(pdata))
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return PTR_ERR(pdata);
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if (!pdata) {
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dev_err(dev, "missing platform data\n");
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return -EINVAL;
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}
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}
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if (!pdata->poll_interval) {
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dev_err(dev, "missing poll_interval value\n");
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return -EINVAL;
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}
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size = sizeof(struct gpio_keys_polled_dev) +
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pdata->nbuttons * sizeof(struct gpio_keys_button_data);
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bdev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
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if (!bdev) {
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dev_err(dev, "no memory for private data\n");
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return -ENOMEM;
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}
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poll_dev = devm_input_allocate_polled_device(&pdev->dev);
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if (!poll_dev) {
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dev_err(dev, "no memory for polled device\n");
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return -ENOMEM;
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}
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poll_dev->private = bdev;
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poll_dev->poll = gpio_keys_polled_poll;
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poll_dev->poll_interval = pdata->poll_interval;
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poll_dev->open = gpio_keys_polled_open;
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poll_dev->close = gpio_keys_polled_close;
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input = poll_dev->input;
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input->name = pdev->name;
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input->phys = DRV_NAME"/input0";
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input->id.bustype = BUS_HOST;
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input->id.vendor = 0x0001;
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input->id.product = 0x0001;
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input->id.version = 0x0100;
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__set_bit(EV_KEY, input->evbit);
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if (pdata->rep)
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__set_bit(EV_REP, input->evbit);
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for (i = 0; i < pdata->nbuttons; i++) {
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struct gpio_keys_button *button = &pdata->buttons[i];
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struct gpio_keys_button_data *bdata = &bdev->data[i];
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unsigned int type = button->type ?: EV_KEY;
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if (button->wakeup) {
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dev_err(dev, DRV_NAME " does not support wakeup\n");
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return -EINVAL;
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}
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/*
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* Legacy GPIO number so request the GPIO here and
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* convert it to descriptor.
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*/
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if (!button->gpiod && gpio_is_valid(button->gpio)) {
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unsigned flags = GPIOF_IN;
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if (button->active_low)
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flags |= GPIOF_ACTIVE_LOW;
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error = devm_gpio_request_one(&pdev->dev, button->gpio,
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flags, button->desc ? : DRV_NAME);
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if (error) {
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dev_err(dev, "unable to claim gpio %u, err=%d\n",
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button->gpio, error);
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return error;
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}
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button->gpiod = gpio_to_desc(button->gpio);
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}
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if (IS_ERR(button->gpiod))
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return PTR_ERR(button->gpiod);
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bdata->can_sleep = gpiod_cansleep(button->gpiod);
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bdata->last_state = -1;
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bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
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pdata->poll_interval);
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input_set_capability(input, type, button->code);
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}
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bdev->poll_dev = poll_dev;
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bdev->dev = dev;
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bdev->pdata = pdata;
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platform_set_drvdata(pdev, bdev);
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error = input_register_polled_device(poll_dev);
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if (error) {
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dev_err(dev, "unable to register polled device, err=%d\n",
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error);
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return error;
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}
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/* report initial state of the buttons */
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for (i = 0; i < pdata->nbuttons; i++)
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gpio_keys_polled_check_state(input, &pdata->buttons[i],
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&bdev->data[i]);
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return 0;
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}
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static struct platform_driver gpio_keys_polled_driver = {
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.probe = gpio_keys_polled_probe,
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.driver = {
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.name = DRV_NAME,
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.of_match_table = gpio_keys_polled_of_match,
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},
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};
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module_platform_driver(gpio_keys_polled_driver);
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MODULE_LICENSE("GPL v2");
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MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
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MODULE_DESCRIPTION("Polled GPIO Buttons driver");
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MODULE_ALIAS("platform:" DRV_NAME);
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