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v3.15
 
  1/*
  2 *  Driver for buttons on GPIO lines not capable of generating interrupts
  3 *
  4 *  Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
  5 *  Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
  6 *
  7 *  This file was based on: /drivers/input/misc/cobalt_btns.c
  8 *	Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
  9 *
 10 *  also was based on: /drivers/input/keyboard/gpio_keys.c
 11 *	Copyright 2005 Phil Blundell
 12 *
 13 *  This program is free software; you can redistribute it and/or modify
 14 *  it under the terms of the GNU General Public License version 2 as
 15 *  published by the Free Software Foundation.
 16 */
 17
 18#include <linux/kernel.h>
 19#include <linux/module.h>
 20#include <linux/slab.h>
 21#include <linux/input.h>
 22#include <linux/input-polldev.h>
 23#include <linux/ioport.h>
 24#include <linux/platform_device.h>
 25#include <linux/gpio.h>
 
 26#include <linux/gpio_keys.h>
 27#include <linux/of.h>
 28#include <linux/of_platform.h>
 29#include <linux/of_gpio.h>
 30
 31#define DRV_NAME	"gpio-keys-polled"
 32
 33struct gpio_keys_button_data {
 
 34	int last_state;
 35	int count;
 36	int threshold;
 37	int can_sleep;
 38};
 39
 40struct gpio_keys_polled_dev {
 41	struct input_polled_dev *poll_dev;
 42	struct device *dev;
 43	const struct gpio_keys_platform_data *pdata;
 
 
 44	struct gpio_keys_button_data data[0];
 45};
 46
 47static void gpio_keys_polled_check_state(struct input_dev *input,
 48					 struct gpio_keys_button *button,
 49					 struct gpio_keys_button_data *bdata)
 50{
 51	int state;
 
 
 52
 53	if (bdata->can_sleep)
 54		state = !!gpio_get_value_cansleep(button->gpio);
 55	else
 56		state = !!gpio_get_value(button->gpio);
 
 
 
 
 
 
 
 
 
 
 
 57
 58	if (state != bdata->last_state) {
 59		unsigned int type = button->type ?: EV_KEY;
 
 
 
 60
 61		input_event(input, type, button->code,
 62			    !!(state ^ button->active_low));
 63		input_sync(input);
 64		bdata->count = 0;
 65		bdata->last_state = state;
 
 
 
 
 
 
 66	}
 67}
 68
 69static void gpio_keys_polled_poll(struct input_polled_dev *dev)
 70{
 71	struct gpio_keys_polled_dev *bdev = dev->private;
 72	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 73	struct input_dev *input = dev->input;
 74	int i;
 75
 
 
 
 76	for (i = 0; i < pdata->nbuttons; i++) {
 77		struct gpio_keys_button_data *bdata = &bdev->data[i];
 78
 79		if (bdata->count < bdata->threshold)
 80			bdata->count++;
 81		else
 82			gpio_keys_polled_check_state(input, &pdata->buttons[i],
 
 
 83						     bdata);
 
 
 
 
 
 
 
 
 
 
 
 84	}
 
 
 85}
 86
 87static void gpio_keys_polled_open(struct input_polled_dev *dev)
 88{
 89	struct gpio_keys_polled_dev *bdev = dev->private;
 90	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 91
 92	if (pdata->enable)
 93		pdata->enable(bdev->dev);
 94}
 95
 96static void gpio_keys_polled_close(struct input_polled_dev *dev)
 97{
 98	struct gpio_keys_polled_dev *bdev = dev->private;
 99	const struct gpio_keys_platform_data *pdata = bdev->pdata;
100
101	if (pdata->disable)
102		pdata->disable(bdev->dev);
103}
104
105#ifdef CONFIG_OF
106static struct gpio_keys_platform_data *gpio_keys_polled_get_devtree_pdata(struct device *dev)
107{
108	struct device_node *node, *pp;
109	struct gpio_keys_platform_data *pdata;
110	struct gpio_keys_button *button;
111	int error;
112	int nbuttons;
113	int i;
114
115	node = dev->of_node;
116	if (!node)
117		return NULL;
118
119	nbuttons = of_get_child_count(node);
120	if (nbuttons == 0)
121		return NULL;
122
123	pdata = kzalloc(sizeof(*pdata) + nbuttons * (sizeof *button),
124			GFP_KERNEL);
125	if (!pdata) {
126		error = -ENOMEM;
127		goto err_out;
128	}
129
130	pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
131	pdata->nbuttons = nbuttons;
132
133	pdata->rep = !!of_get_property(node, "autorepeat", NULL);
134	of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
135
136	i = 0;
137	for_each_child_of_node(node, pp) {
138		int gpio;
139		enum of_gpio_flags flags;
140
141		if (!of_find_property(pp, "gpios", NULL)) {
142			pdata->nbuttons--;
143			dev_warn(dev, "Found button without gpios\n");
144			continue;
145		}
146
147		gpio = of_get_gpio_flags(pp, 0, &flags);
148		if (gpio < 0) {
149			error = gpio;
150			if (error != -EPROBE_DEFER)
151				dev_err(dev,
152					"Failed to get gpio flags, error: %d\n",
153					error);
154			goto err_free_pdata;
155		}
156
157		button = &pdata->buttons[i++];
 
158
159		button->gpio = gpio;
160		button->active_low = flags & OF_GPIO_ACTIVE_LOW;
161
162		if (of_property_read_u32(pp, "linux,code", &button->code)) {
163			dev_err(dev, "Button without keycode: 0x%x\n",
164				button->gpio);
165			error = -EINVAL;
166			goto err_free_pdata;
 
167		}
168
169		button->desc = of_get_property(pp, "label", NULL);
170
171		if (of_property_read_u32(pp, "linux,input-type", &button->type))
 
172			button->type = EV_KEY;
173
174		button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
 
 
 
 
 
 
 
175
176		if (of_property_read_u32(pp, "debounce-interval",
177					 &button->debounce_interval))
178			button->debounce_interval = 5;
179	}
180
181	if (pdata->nbuttons == 0) {
182		error = -EINVAL;
183		goto err_free_pdata;
184	}
185
186	return pdata;
 
 
 
 
 
 
 
 
 
187
188err_free_pdata:
189	kfree(pdata);
190err_out:
191	return ERR_PTR(error);
 
 
 
 
 
 
192}
193
194static struct of_device_id gpio_keys_polled_of_match[] = {
195	{ .compatible = "gpio-keys-polled", },
196	{ },
197};
198MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
199
200#else
201
202static inline struct gpio_keys_platform_data *
203gpio_keys_polled_get_devtree_pdata(struct device *dev)
204{
205	return NULL;
206}
207#endif
208
209static int gpio_keys_polled_probe(struct platform_device *pdev)
210{
211	struct device *dev = &pdev->dev;
 
212	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
213	struct gpio_keys_polled_dev *bdev;
214	struct input_polled_dev *poll_dev;
215	struct input_dev *input;
216	int error;
217	int i;
218
219	if (!pdata) {
220		pdata = gpio_keys_polled_get_devtree_pdata(dev);
221		if (IS_ERR(pdata))
222			return PTR_ERR(pdata);
223		if (!pdata) {
224			dev_err(dev, "missing platform data\n");
225			return -EINVAL;
226		}
227	}
228
229	if (!pdata->poll_interval) {
230		dev_err(dev, "missing poll_interval value\n");
231		error = -EINVAL;
232		goto err_free_pdata;
233	}
234
235	bdev = kzalloc(sizeof(struct gpio_keys_polled_dev) +
236		       pdata->nbuttons * sizeof(struct gpio_keys_button_data),
237		       GFP_KERNEL);
238	if (!bdev) {
239		dev_err(dev, "no memory for private data\n");
240		error = -ENOMEM;
241		goto err_free_pdata;
242	}
243
244	poll_dev = input_allocate_polled_device();
245	if (!poll_dev) {
246		dev_err(dev, "no memory for polled device\n");
247		error = -ENOMEM;
248		goto err_free_bdev;
249	}
250
251	poll_dev->private = bdev;
252	poll_dev->poll = gpio_keys_polled_poll;
253	poll_dev->poll_interval = pdata->poll_interval;
254	poll_dev->open = gpio_keys_polled_open;
255	poll_dev->close = gpio_keys_polled_close;
256
257	input = poll_dev->input;
258
259	input->name = pdev->name;
260	input->phys = DRV_NAME"/input0";
261	input->dev.parent = &pdev->dev;
262
263	input->id.bustype = BUS_HOST;
264	input->id.vendor = 0x0001;
265	input->id.product = 0x0001;
266	input->id.version = 0x0100;
267
268	__set_bit(EV_KEY, input->evbit);
269	if (pdata->rep)
270		__set_bit(EV_REP, input->evbit);
271
272	for (i = 0; i < pdata->nbuttons; i++) {
273		struct gpio_keys_button *button = &pdata->buttons[i];
274		struct gpio_keys_button_data *bdata = &bdev->data[i];
275		unsigned int gpio = button->gpio;
276		unsigned int type = button->type ?: EV_KEY;
277
278		if (button->wakeup) {
279			dev_err(dev, DRV_NAME " does not support wakeup\n");
280			error = -EINVAL;
281			goto err_free_gpio;
282		}
283
284		error = gpio_request_one(gpio, GPIOF_IN,
285					 button->desc ?: DRV_NAME);
286		if (error) {
287			dev_err(dev, "unable to claim gpio %u, err=%d\n",
288				gpio, error);
289			goto err_free_gpio;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
290		}
291
292		bdata->can_sleep = gpio_cansleep(gpio);
293		bdata->last_state = -1;
294		bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
295						pdata->poll_interval);
296
297		input_set_capability(input, type, button->code);
 
 
 
298	}
299
 
 
300	bdev->poll_dev = poll_dev;
301	bdev->dev = dev;
302	bdev->pdata = pdata;
303	platform_set_drvdata(pdev, bdev);
304
305	error = input_register_polled_device(poll_dev);
306	if (error) {
307		dev_err(dev, "unable to register polled device, err=%d\n",
308			error);
309		goto err_free_gpio;
310	}
311
312	/* report initial state of the buttons */
313	for (i = 0; i < pdata->nbuttons; i++)
314		gpio_keys_polled_check_state(input, &pdata->buttons[i],
315					     &bdev->data[i]);
316
317	return 0;
318
319err_free_gpio:
320	while (--i >= 0)
321		gpio_free(pdata->buttons[i].gpio);
322
323	input_free_polled_device(poll_dev);
324
325err_free_bdev:
326	kfree(bdev);
327
328err_free_pdata:
329	/* If we have no platform_data, we allocated pdata dynamically.  */
330	if (!dev_get_platdata(&pdev->dev))
331		kfree(pdata);
332
333	return error;
334}
335
336static int gpio_keys_polled_remove(struct platform_device *pdev)
337{
338	struct gpio_keys_polled_dev *bdev = platform_get_drvdata(pdev);
339	const struct gpio_keys_platform_data *pdata = bdev->pdata;
340	int i;
341
342	input_unregister_polled_device(bdev->poll_dev);
343
344	for (i = 0; i < pdata->nbuttons; i++)
345		gpio_free(pdata->buttons[i].gpio);
346
347	input_free_polled_device(bdev->poll_dev);
348
349	/*
350	 * If we had no platform_data, we allocated pdata dynamically and
351	 * must free it here.
352	 */
353	if (!dev_get_platdata(&pdev->dev))
354		kfree(pdata);
355
356	kfree(bdev);
357
358	return 0;
359}
360
361static struct platform_driver gpio_keys_polled_driver = {
362	.probe	= gpio_keys_polled_probe,
363	.remove	= gpio_keys_polled_remove,
364	.driver	= {
365		.name	= DRV_NAME,
366		.owner	= THIS_MODULE,
367		.of_match_table = of_match_ptr(gpio_keys_polled_of_match),
368	},
369};
370module_platform_driver(gpio_keys_polled_driver);
371
372MODULE_LICENSE("GPL v2");
373MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
374MODULE_DESCRIPTION("Polled GPIO Buttons driver");
375MODULE_ALIAS("platform:" DRV_NAME);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Driver for buttons on GPIO lines not capable of generating interrupts
  4 *
  5 *  Copyright (C) 2007-2010 Gabor Juhos <juhosg@openwrt.org>
  6 *  Copyright (C) 2010 Nuno Goncalves <nunojpg@gmail.com>
  7 *
  8 *  This file was based on: /drivers/input/misc/cobalt_btns.c
  9 *	Copyright (C) 2007 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
 10 *
 11 *  also was based on: /drivers/input/keyboard/gpio_keys.c
 12 *	Copyright 2005 Phil Blundell
 
 
 
 
 13 */
 14
 15#include <linux/kernel.h>
 16#include <linux/module.h>
 17#include <linux/slab.h>
 18#include <linux/input.h>
 19#include <linux/input-polldev.h>
 20#include <linux/ioport.h>
 21#include <linux/platform_device.h>
 22#include <linux/gpio.h>
 23#include <linux/gpio/consumer.h>
 24#include <linux/gpio_keys.h>
 25#include <linux/property.h>
 
 
 26
 27#define DRV_NAME	"gpio-keys-polled"
 28
 29struct gpio_keys_button_data {
 30	struct gpio_desc *gpiod;
 31	int last_state;
 32	int count;
 33	int threshold;
 
 34};
 35
 36struct gpio_keys_polled_dev {
 37	struct input_polled_dev *poll_dev;
 38	struct device *dev;
 39	const struct gpio_keys_platform_data *pdata;
 40	unsigned long rel_axis_seen[BITS_TO_LONGS(REL_CNT)];
 41	unsigned long abs_axis_seen[BITS_TO_LONGS(ABS_CNT)];
 42	struct gpio_keys_button_data data[0];
 43};
 44
 45static void gpio_keys_button_event(struct input_polled_dev *dev,
 46				   const struct gpio_keys_button *button,
 47				   int state)
 48{
 49	struct gpio_keys_polled_dev *bdev = dev->private;
 50	struct input_dev *input = dev->input;
 51	unsigned int type = button->type ?: EV_KEY;
 52
 53	if (type == EV_REL) {
 54		if (state) {
 55			input_event(input, type, button->code, button->value);
 56			__set_bit(button->code, bdev->rel_axis_seen);
 57		}
 58	} else if (type == EV_ABS) {
 59		if (state) {
 60			input_event(input, type, button->code, button->value);
 61			__set_bit(button->code, bdev->abs_axis_seen);
 62		}
 63	} else {
 64		input_event(input, type, button->code, state);
 65		input_sync(input);
 66	}
 67}
 68
 69static void gpio_keys_polled_check_state(struct input_polled_dev *dev,
 70					 const struct gpio_keys_button *button,
 71					 struct gpio_keys_button_data *bdata)
 72{
 73	int state;
 74
 75	state = gpiod_get_value_cansleep(bdata->gpiod);
 76	if (state < 0) {
 77		dev_err(dev->input->dev.parent,
 78			"failed to get gpio state: %d\n", state);
 79	} else {
 80		gpio_keys_button_event(dev, button, state);
 81
 82		if (state != bdata->last_state) {
 83			bdata->count = 0;
 84			bdata->last_state = state;
 85		}
 86	}
 87}
 88
 89static void gpio_keys_polled_poll(struct input_polled_dev *dev)
 90{
 91	struct gpio_keys_polled_dev *bdev = dev->private;
 92	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 93	struct input_dev *input = dev->input;
 94	int i;
 95
 96	memset(bdev->rel_axis_seen, 0, sizeof(bdev->rel_axis_seen));
 97	memset(bdev->abs_axis_seen, 0, sizeof(bdev->abs_axis_seen));
 98
 99	for (i = 0; i < pdata->nbuttons; i++) {
100		struct gpio_keys_button_data *bdata = &bdev->data[i];
101
102		if (bdata->count < bdata->threshold) {
103			bdata->count++;
104			gpio_keys_button_event(dev, &pdata->buttons[i],
105					       bdata->last_state);
106		} else {
107			gpio_keys_polled_check_state(dev, &pdata->buttons[i],
108						     bdata);
109		}
110	}
111
112	for_each_set_bit(i, input->relbit, REL_CNT) {
113		if (!test_bit(i, bdev->rel_axis_seen))
114			input_event(input, EV_REL, i, 0);
115	}
116
117	for_each_set_bit(i, input->absbit, ABS_CNT) {
118		if (!test_bit(i, bdev->abs_axis_seen))
119			input_event(input, EV_ABS, i, 0);
120	}
121
122	input_sync(input);
123}
124
125static void gpio_keys_polled_open(struct input_polled_dev *dev)
126{
127	struct gpio_keys_polled_dev *bdev = dev->private;
128	const struct gpio_keys_platform_data *pdata = bdev->pdata;
129
130	if (pdata->enable)
131		pdata->enable(bdev->dev);
132}
133
134static void gpio_keys_polled_close(struct input_polled_dev *dev)
135{
136	struct gpio_keys_polled_dev *bdev = dev->private;
137	const struct gpio_keys_platform_data *pdata = bdev->pdata;
138
139	if (pdata->disable)
140		pdata->disable(bdev->dev);
141}
142
143static struct gpio_keys_platform_data *
144gpio_keys_polled_get_devtree_pdata(struct device *dev)
145{
 
146	struct gpio_keys_platform_data *pdata;
147	struct gpio_keys_button *button;
148	struct fwnode_handle *child;
149	int nbuttons;
 
 
 
 
 
150
151	nbuttons = device_get_child_node_count(dev);
152	if (nbuttons == 0)
153		return ERR_PTR(-EINVAL);
154
155	pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * sizeof(*button),
156			     GFP_KERNEL);
157	if (!pdata)
158		return ERR_PTR(-ENOMEM);
 
 
159
160	button = (struct gpio_keys_button *)(pdata + 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
161
162	pdata->buttons = button;
163	pdata->nbuttons = nbuttons;
 
 
 
 
 
 
 
164
165	pdata->rep = device_property_present(dev, "autorepeat");
166	device_property_read_u32(dev, "poll-interval", &pdata->poll_interval);
167
168	device_property_read_string(dev, "label", &pdata->name);
 
169
170	device_for_each_child_node(dev, child) {
171		if (fwnode_property_read_u32(child, "linux,code",
172					     &button->code)) {
173			dev_err(dev, "button without keycode\n");
174			fwnode_handle_put(child);
175			return ERR_PTR(-EINVAL);
176		}
177
178		fwnode_property_read_string(child, "label", &button->desc);
179
180		if (fwnode_property_read_u32(child, "linux,input-type",
181					     &button->type))
182			button->type = EV_KEY;
183
184		if (fwnode_property_read_u32(child, "linux,input-value",
185					     (u32 *)&button->value))
186			button->value = 1;
187
188		button->wakeup =
189			fwnode_property_read_bool(child, "wakeup-source") ||
190			/* legacy name */
191			fwnode_property_read_bool(child, "gpio-key,wakeup");
192
193		if (fwnode_property_read_u32(child, "debounce-interval",
194					     &button->debounce_interval))
195			button->debounce_interval = 5;
 
196
197		button++;
 
 
198	}
199
200	return pdata;
201}
202
203static void gpio_keys_polled_set_abs_params(struct input_dev *input,
204	const struct gpio_keys_platform_data *pdata, unsigned int code)
205{
206	int i, min = 0, max = 0;
207
208	for (i = 0; i < pdata->nbuttons; i++) {
209		const struct gpio_keys_button *button = &pdata->buttons[i];
210
211		if (button->type != EV_ABS || button->code != code)
212			continue;
213
214		if (button->value < min)
215			min = button->value;
216		if (button->value > max)
217			max = button->value;
218	}
219
220	input_set_abs_params(input, code, min, max, 0, 0);
221}
222
223static const struct of_device_id gpio_keys_polled_of_match[] = {
224	{ .compatible = "gpio-keys-polled", },
225	{ },
226};
227MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
228
 
 
 
 
 
 
 
 
 
229static int gpio_keys_polled_probe(struct platform_device *pdev)
230{
231	struct device *dev = &pdev->dev;
232	struct fwnode_handle *child = NULL;
233	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
234	struct gpio_keys_polled_dev *bdev;
235	struct input_polled_dev *poll_dev;
236	struct input_dev *input;
237	int error;
238	int i;
239
240	if (!pdata) {
241		pdata = gpio_keys_polled_get_devtree_pdata(dev);
242		if (IS_ERR(pdata))
243			return PTR_ERR(pdata);
 
 
 
 
244	}
245
246	if (!pdata->poll_interval) {
247		dev_err(dev, "missing poll_interval value\n");
248		return -EINVAL;
 
249	}
250
251	bdev = devm_kzalloc(dev, struct_size(bdev, data, pdata->nbuttons),
252			    GFP_KERNEL);
 
253	if (!bdev) {
254		dev_err(dev, "no memory for private data\n");
255		return -ENOMEM;
 
256	}
257
258	poll_dev = devm_input_allocate_polled_device(dev);
259	if (!poll_dev) {
260		dev_err(dev, "no memory for polled device\n");
261		return -ENOMEM;
 
262	}
263
264	poll_dev->private = bdev;
265	poll_dev->poll = gpio_keys_polled_poll;
266	poll_dev->poll_interval = pdata->poll_interval;
267	poll_dev->open = gpio_keys_polled_open;
268	poll_dev->close = gpio_keys_polled_close;
269
270	input = poll_dev->input;
271
272	input->name = pdata->name ?: pdev->name;
273	input->phys = DRV_NAME"/input0";
 
274
275	input->id.bustype = BUS_HOST;
276	input->id.vendor = 0x0001;
277	input->id.product = 0x0001;
278	input->id.version = 0x0100;
279
280	__set_bit(EV_KEY, input->evbit);
281	if (pdata->rep)
282		__set_bit(EV_REP, input->evbit);
283
284	for (i = 0; i < pdata->nbuttons; i++) {
285		const struct gpio_keys_button *button = &pdata->buttons[i];
286		struct gpio_keys_button_data *bdata = &bdev->data[i];
 
287		unsigned int type = button->type ?: EV_KEY;
288
289		if (button->wakeup) {
290			dev_err(dev, DRV_NAME " does not support wakeup\n");
291			fwnode_handle_put(child);
292			return -EINVAL;
293		}
294
295		if (!dev_get_platdata(dev)) {
296			/* No legacy static platform data */
297			child = device_get_next_child_node(dev, child);
298			if (!child) {
299				dev_err(dev, "missing child device node\n");
300				return -EINVAL;
301			}
302
303			bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev,
304								NULL, child,
305								GPIOD_IN,
306								button->desc);
307			if (IS_ERR(bdata->gpiod)) {
308				error = PTR_ERR(bdata->gpiod);
309				if (error != -EPROBE_DEFER)
310					dev_err(dev,
311						"failed to get gpio: %d\n",
312						error);
313				fwnode_handle_put(child);
314				return error;
315			}
316		} else if (gpio_is_valid(button->gpio)) {
317			/*
318			 * Legacy GPIO number so request the GPIO here and
319			 * convert it to descriptor.
320			 */
321			unsigned flags = GPIOF_IN;
322
323			if (button->active_low)
324				flags |= GPIOF_ACTIVE_LOW;
325
326			error = devm_gpio_request_one(dev, button->gpio,
327					flags, button->desc ? : DRV_NAME);
328			if (error) {
329				dev_err(dev,
330					"unable to claim gpio %u, err=%d\n",
331					button->gpio, error);
332				return error;
333			}
334
335			bdata->gpiod = gpio_to_desc(button->gpio);
336			if (!bdata->gpiod) {
337				dev_err(dev,
338					"unable to convert gpio %u to descriptor\n",
339					button->gpio);
340				return -EINVAL;
341			}
342		}
343
 
344		bdata->last_state = -1;
345		bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
346						pdata->poll_interval);
347
348		input_set_capability(input, type, button->code);
349		if (type == EV_ABS)
350			gpio_keys_polled_set_abs_params(input, pdata,
351							button->code);
352	}
353
354	fwnode_handle_put(child);
355
356	bdev->poll_dev = poll_dev;
357	bdev->dev = dev;
358	bdev->pdata = pdata;
 
359
360	error = input_register_polled_device(poll_dev);
361	if (error) {
362		dev_err(dev, "unable to register polled device, err=%d\n",
363			error);
364		return error;
365	}
366
367	/* report initial state of the buttons */
368	for (i = 0; i < pdata->nbuttons; i++)
369		gpio_keys_polled_check_state(poll_dev, &pdata->buttons[i],
370					     &bdev->data[i]);
371
372	input_sync(input);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
373
374	return 0;
375}
376
377static struct platform_driver gpio_keys_polled_driver = {
378	.probe	= gpio_keys_polled_probe,
 
379	.driver	= {
380		.name	= DRV_NAME,
381		.of_match_table = gpio_keys_polled_of_match,
 
382	},
383};
384module_platform_driver(gpio_keys_polled_driver);
385
386MODULE_LICENSE("GPL v2");
387MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
388MODULE_DESCRIPTION("Polled GPIO Buttons driver");
389MODULE_ALIAS("platform:" DRV_NAME);