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v6.13.7
  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/ioport.h>
 20#include <linux/platform_device.h>
 21#include <linux/gpio.h>
 22#include <linux/gpio/consumer.h>
 23#include <linux/gpio_keys.h>
 24#include <linux/property.h>
 25
 26#define DRV_NAME	"gpio-keys-polled"
 27
 28struct gpio_keys_button_data {
 29	struct gpio_desc *gpiod;
 30	int last_state;
 31	int count;
 32	int threshold;
 33};
 34
 35struct gpio_keys_polled_dev {
 36	struct input_dev *input;
 37	struct device *dev;
 38	const struct gpio_keys_platform_data *pdata;
 39	unsigned long rel_axis_seen[BITS_TO_LONGS(REL_CNT)];
 40	unsigned long abs_axis_seen[BITS_TO_LONGS(ABS_CNT)];
 41	struct gpio_keys_button_data data[];
 42};
 43
 44static void gpio_keys_button_event(struct input_dev *input,
 45				   const struct gpio_keys_button *button,
 46				   int state)
 47{
 48	struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
 
 49	unsigned int type = button->type ?: EV_KEY;
 50
 51	if (type == EV_REL) {
 52		if (state) {
 53			input_event(input, type, button->code, button->value);
 54			__set_bit(button->code, bdev->rel_axis_seen);
 55		}
 56	} else if (type == EV_ABS) {
 57		if (state) {
 58			input_event(input, type, button->code, button->value);
 59			__set_bit(button->code, bdev->abs_axis_seen);
 60		}
 61	} else {
 62		input_event(input, type, button->code, state);
 63		input_sync(input);
 64	}
 65}
 66
 67static void gpio_keys_polled_check_state(struct input_dev *input,
 68					 const struct gpio_keys_button *button,
 69					 struct gpio_keys_button_data *bdata)
 70{
 71	int state;
 72
 73	state = gpiod_get_value_cansleep(bdata->gpiod);
 74	if (state < 0) {
 75		dev_err(input->dev.parent,
 76			"failed to get gpio state: %d\n", state);
 77	} else {
 78		gpio_keys_button_event(input, button, state);
 79
 80		if (state != bdata->last_state) {
 81			bdata->count = 0;
 82			bdata->last_state = state;
 83		}
 84	}
 85}
 86
 87static void gpio_keys_polled_poll(struct input_dev *input)
 88{
 89	struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
 90	const struct gpio_keys_platform_data *pdata = bdev->pdata;
 
 91	int i;
 92
 93	memset(bdev->rel_axis_seen, 0, sizeof(bdev->rel_axis_seen));
 94	memset(bdev->abs_axis_seen, 0, sizeof(bdev->abs_axis_seen));
 95
 96	for (i = 0; i < pdata->nbuttons; i++) {
 97		struct gpio_keys_button_data *bdata = &bdev->data[i];
 98
 99		if (bdata->count < bdata->threshold) {
100			bdata->count++;
101			gpio_keys_button_event(input, &pdata->buttons[i],
102					       bdata->last_state);
103		} else {
104			gpio_keys_polled_check_state(input, &pdata->buttons[i],
105						     bdata);
106		}
107	}
108
109	for_each_set_bit(i, input->relbit, REL_CNT) {
110		if (!test_bit(i, bdev->rel_axis_seen))
111			input_event(input, EV_REL, i, 0);
112	}
113
114	for_each_set_bit(i, input->absbit, ABS_CNT) {
115		if (!test_bit(i, bdev->abs_axis_seen))
116			input_event(input, EV_ABS, i, 0);
117	}
118
119	input_sync(input);
120}
121
122static int gpio_keys_polled_open(struct input_dev *input)
123{
124	struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
125	const struct gpio_keys_platform_data *pdata = bdev->pdata;
126
127	if (pdata->enable)
128		pdata->enable(bdev->dev);
129
130	return 0;
131}
132
133static void gpio_keys_polled_close(struct input_dev *input)
134{
135	struct gpio_keys_polled_dev *bdev = input_get_drvdata(input);
136	const struct gpio_keys_platform_data *pdata = bdev->pdata;
137
138	if (pdata->disable)
139		pdata->disable(bdev->dev);
140}
141
142static struct gpio_keys_platform_data *
143gpio_keys_polled_get_devtree_pdata(struct device *dev)
144{
145	struct gpio_keys_platform_data *pdata;
146	struct gpio_keys_button *button;
 
147	int nbuttons;
148
149	nbuttons = device_get_child_node_count(dev);
150	if (nbuttons == 0)
151		return ERR_PTR(-EINVAL);
152
153	pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * sizeof(*button),
154			     GFP_KERNEL);
155	if (!pdata)
156		return ERR_PTR(-ENOMEM);
157
158	button = (struct gpio_keys_button *)(pdata + 1);
159
160	pdata->buttons = button;
161	pdata->nbuttons = nbuttons;
162
163	pdata->rep = device_property_present(dev, "autorepeat");
164	device_property_read_u32(dev, "poll-interval", &pdata->poll_interval);
165
166	device_property_read_string(dev, "label", &pdata->name);
167
168	device_for_each_child_node_scoped(dev, child) {
169		if (fwnode_property_read_u32(child, "linux,code",
170					     &button->code)) {
171			dev_err(dev, "button without keycode\n");
 
172			return ERR_PTR(-EINVAL);
173		}
174
175		fwnode_property_read_string(child, "label", &button->desc);
176
177		if (fwnode_property_read_u32(child, "linux,input-type",
178					     &button->type))
179			button->type = EV_KEY;
180
181		if (fwnode_property_read_u32(child, "linux,input-value",
182					     (u32 *)&button->value))
183			button->value = 1;
184
185		button->wakeup =
186			fwnode_property_read_bool(child, "wakeup-source") ||
187			/* legacy name */
188			fwnode_property_read_bool(child, "gpio-key,wakeup");
189
190		if (fwnode_property_read_u32(child, "debounce-interval",
191					     &button->debounce_interval))
192			button->debounce_interval = 5;
193
194		button++;
195	}
196
197	return pdata;
198}
199
200static void gpio_keys_polled_set_abs_params(struct input_dev *input,
201	const struct gpio_keys_platform_data *pdata, unsigned int code)
202{
203	int i, min = 0, max = 0;
204
205	for (i = 0; i < pdata->nbuttons; i++) {
206		const struct gpio_keys_button *button = &pdata->buttons[i];
207
208		if (button->type != EV_ABS || button->code != code)
209			continue;
210
211		if (button->value < min)
212			min = button->value;
213		if (button->value > max)
214			max = button->value;
215	}
216
217	input_set_abs_params(input, code, min, max, 0, 0);
218}
219
220static const struct of_device_id gpio_keys_polled_of_match[] = {
221	{ .compatible = "gpio-keys-polled", },
222	{ },
223};
224MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
225
226static int gpio_keys_polled_probe(struct platform_device *pdev)
227{
228	struct device *dev = &pdev->dev;
229	struct fwnode_handle *child = NULL;
230	const struct gpio_keys_platform_data *pdata = dev_get_platdata(dev);
231	struct gpio_keys_polled_dev *bdev;
 
232	struct input_dev *input;
233	int error;
234	int i;
235
236	if (!pdata) {
237		pdata = gpio_keys_polled_get_devtree_pdata(dev);
238		if (IS_ERR(pdata))
239			return PTR_ERR(pdata);
240	}
241
242	if (!pdata->poll_interval) {
243		dev_err(dev, "missing poll_interval value\n");
244		return -EINVAL;
245	}
246
247	bdev = devm_kzalloc(dev, struct_size(bdev, data, pdata->nbuttons),
248			    GFP_KERNEL);
249	if (!bdev) {
250		dev_err(dev, "no memory for private data\n");
251		return -ENOMEM;
252	}
253
254	input = devm_input_allocate_device(dev);
255	if (!input) {
256		dev_err(dev, "no memory for input device\n");
257		return -ENOMEM;
258	}
259
260	input_set_drvdata(input, bdev);
 
 
 
 
 
 
261
262	input->name = pdata->name ?: pdev->name;
263	input->phys = DRV_NAME"/input0";
264
265	input->id.bustype = BUS_HOST;
266	input->id.vendor = 0x0001;
267	input->id.product = 0x0001;
268	input->id.version = 0x0100;
269
270	input->open = gpio_keys_polled_open;
271	input->close = gpio_keys_polled_close;
272
273	__set_bit(EV_KEY, input->evbit);
274	if (pdata->rep)
275		__set_bit(EV_REP, input->evbit);
276
277	for (i = 0; i < pdata->nbuttons; i++) {
278		const struct gpio_keys_button *button = &pdata->buttons[i];
279		struct gpio_keys_button_data *bdata = &bdev->data[i];
280		unsigned int type = button->type ?: EV_KEY;
281
282		if (button->wakeup) {
283			dev_err(dev, DRV_NAME " does not support wakeup\n");
284			fwnode_handle_put(child);
285			return -EINVAL;
286		}
287
288		if (!dev_get_platdata(dev)) {
289			/* No legacy static platform data */
290			child = device_get_next_child_node(dev, child);
291			if (!child) {
292				dev_err(dev, "missing child device node\n");
293				return -EINVAL;
294			}
295
296			bdata->gpiod = devm_fwnode_gpiod_get(dev, child,
297							     NULL, GPIOD_IN,
298							     button->desc);
 
299			if (IS_ERR(bdata->gpiod)) {
 
 
 
 
 
300				fwnode_handle_put(child);
301				return dev_err_probe(dev, PTR_ERR(bdata->gpiod),
302						     "failed to get gpio\n");
303			}
304		} else if (gpio_is_valid(button->gpio)) {
305			/*
306			 * Legacy GPIO number so request the GPIO here and
307			 * convert it to descriptor.
308			 */
309			error = devm_gpio_request_one(dev, button->gpio, GPIOF_IN,
310						      button->desc ? : DRV_NAME);
311			if (error)
312				return dev_err_probe(dev, error,
313						     "unable to claim gpio %u\n",
314						     button->gpio);
 
 
 
 
 
 
 
315
316			bdata->gpiod = gpio_to_desc(button->gpio);
317			if (!bdata->gpiod) {
318				dev_err(dev,
319					"unable to convert gpio %u to descriptor\n",
320					button->gpio);
321				return -EINVAL;
322			}
323
324			if (button->active_low ^ gpiod_is_active_low(bdata->gpiod))
325				gpiod_toggle_active_low(bdata->gpiod);
326		}
327
328		bdata->last_state = -1;
329		bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
330						pdata->poll_interval);
331
332		input_set_capability(input, type, button->code);
333		if (type == EV_ABS)
334			gpio_keys_polled_set_abs_params(input, pdata,
335							button->code);
336	}
337
338	fwnode_handle_put(child);
339
340	bdev->input = input;
341	bdev->dev = dev;
342	bdev->pdata = pdata;
343
344	error = input_setup_polling(input, gpio_keys_polled_poll);
345	if (error) {
346		dev_err(dev, "unable to set up polling, err=%d\n", error);
347		return error;
348	}
349
350	input_set_poll_interval(input, pdata->poll_interval);
351
352	error = input_register_device(input);
353	if (error) {
354		dev_err(dev, "unable to register polled device, err=%d\n",
355			error);
356		return error;
357	}
358
359	/* report initial state of the buttons */
360	for (i = 0; i < pdata->nbuttons; i++)
361		gpio_keys_polled_check_state(input, &pdata->buttons[i],
362					     &bdev->data[i]);
363
364	input_sync(input);
365
366	return 0;
367}
368
369static struct platform_driver gpio_keys_polled_driver = {
370	.probe	= gpio_keys_polled_probe,
371	.driver	= {
372		.name	= DRV_NAME,
373		.of_match_table = gpio_keys_polled_of_match,
374	},
375};
376module_platform_driver(gpio_keys_polled_driver);
377
378MODULE_LICENSE("GPL v2");
379MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
380MODULE_DESCRIPTION("Polled GPIO Buttons driver");
381MODULE_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);