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v3.15
 
  1/*
  2 * ST1232 Touchscreen Controller Driver
  3 *
  4 * Copyright (C) 2010 Renesas Solutions Corp.
  5 *	Tony SIM <chinyeow.sim.xt@renesas.com>
  6 *
  7 * Using code from:
  8 *  - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
  9 *	Copyright (C) 2007 Google, Inc.
 10 *
 11 * This software is licensed under the terms of the GNU General Public
 12 * License version 2, as published by the Free Software Foundation, and
 13 * may be copied, distributed, and modified under those terms.
 14 *
 15 * This program is distributed in the hope that it will be useful,
 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 18 * GNU General Public License for more details.
 19 */
 20
 21#include <linux/delay.h>
 22#include <linux/gpio.h>
 23#include <linux/i2c.h>
 24#include <linux/input.h>
 
 
 25#include <linux/interrupt.h>
 26#include <linux/module.h>
 27#include <linux/of.h>
 28#include <linux/of_gpio.h>
 29#include <linux/pm_qos.h>
 30#include <linux/slab.h>
 31#include <linux/types.h>
 32#include <linux/platform_data/st1232_pdata.h>
 33
 34#define ST1232_TS_NAME	"st1232-ts"
 
 35
 36#define MIN_X		0x00
 37#define MIN_Y		0x00
 38#define MAX_X		0x31f	/* (800 - 1) */
 39#define MAX_Y		0x1df	/* (480 - 1) */
 40#define MAX_AREA	0xff
 41#define MAX_FINGERS	2
 42
 43struct st1232_ts_finger {
 44	u16 x;
 45	u16 y;
 46	u8 t;
 47	bool is_valid;
 48};
 49
 50struct st1232_ts_data {
 51	struct i2c_client *client;
 52	struct input_dev *input_dev;
 53	struct st1232_ts_finger finger[MAX_FINGERS];
 54	struct dev_pm_qos_request low_latency_req;
 55	int reset_gpio;
 
 
 
 56};
 57
 58static int st1232_ts_read_data(struct st1232_ts_data *ts)
 59{
 60	struct st1232_ts_finger *finger = ts->finger;
 61	struct i2c_client *client = ts->client;
 62	struct i2c_msg msg[2];
 63	int error;
 64	u8 start_reg;
 65	u8 buf[10];
 
 
 
 
 
 
 
 
 
 
 
 66
 67	/* read touchscreen data from ST1232 */
 68	msg[0].addr = client->addr;
 69	msg[0].flags = 0;
 70	msg[0].len = 1;
 71	msg[0].buf = &start_reg;
 72	start_reg = 0x10;
 73
 74	msg[1].addr = ts->client->addr;
 75	msg[1].flags = I2C_M_RD;
 76	msg[1].len = sizeof(buf);
 77	msg[1].buf = buf;
 78
 79	error = i2c_transfer(client->adapter, msg, 2);
 80	if (error < 0)
 81		return error;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 82
 83	/* get "valid" bits */
 84	finger[0].is_valid = buf[2] >> 7;
 85	finger[1].is_valid = buf[5] >> 7;
 86
 87	/* get xy coordinate */
 88	if (finger[0].is_valid) {
 89		finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
 90		finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
 91		finger[0].t = buf[8];
 92	}
 93
 94	if (finger[1].is_valid) {
 95		finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
 96		finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
 97		finger[1].t = buf[9];
 
 
 
 
 98	}
 99
100	return 0;
 
 
 
101}
102
103static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
104{
105	struct st1232_ts_data *ts = dev_id;
106	struct st1232_ts_finger *finger = ts->finger;
107	struct input_dev *input_dev = ts->input_dev;
108	int count = 0;
109	int i, ret;
110
111	ret = st1232_ts_read_data(ts);
112	if (ret < 0)
113		goto end;
114
115	/* multi touch protocol */
116	for (i = 0; i < MAX_FINGERS; i++) {
117		if (!finger[i].is_valid)
118			continue;
119
120		input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
121		input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
122		input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
123		input_mt_sync(input_dev);
124		count++;
125	}
126
127	/* SYN_MT_REPORT only if no contact */
128	if (!count) {
129		input_mt_sync(input_dev);
130		if (ts->low_latency_req.dev) {
131			dev_pm_qos_remove_request(&ts->low_latency_req);
132			ts->low_latency_req.dev = NULL;
133		}
134	} else if (!ts->low_latency_req.dev) {
135		/* First contact, request 100 us latency. */
136		dev_pm_qos_add_ancestor_request(&ts->client->dev,
137						&ts->low_latency_req,
138						DEV_PM_QOS_RESUME_LATENCY, 100);
139	}
140
141	/* SYN_REPORT */
142	input_sync(input_dev);
143
144end:
145	return IRQ_HANDLED;
146}
147
148static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
149{
150	if (gpio_is_valid(ts->reset_gpio))
151		gpio_direction_output(ts->reset_gpio, poweron);
 
 
 
 
 
152}
153
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
154static int st1232_ts_probe(struct i2c_client *client,
155					const struct i2c_device_id *id)
156{
 
157	struct st1232_ts_data *ts;
158	struct st1232_pdata *pdata = dev_get_platdata(&client->dev);
159	struct input_dev *input_dev;
160	int error;
161
 
 
 
 
 
 
 
 
162	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
163		dev_err(&client->dev, "need I2C_FUNC_I2C\n");
164		return -EIO;
165	}
166
167	if (!client->irq) {
168		dev_err(&client->dev, "no IRQ?\n");
169		return -EINVAL;
170	}
171
172	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
173	if (!ts)
174		return -ENOMEM;
175
 
 
 
 
 
 
 
 
176	input_dev = devm_input_allocate_device(&client->dev);
177	if (!input_dev)
178		return -ENOMEM;
179
180	ts->client = client;
181	ts->input_dev = input_dev;
182
183	if (pdata)
184		ts->reset_gpio = pdata->reset_gpio;
185	else if (client->dev.of_node)
186		ts->reset_gpio = of_get_gpio(client->dev.of_node, 0);
187	else
188		ts->reset_gpio = -ENODEV;
189
190	if (gpio_is_valid(ts->reset_gpio)) {
191		error = devm_gpio_request(&client->dev, ts->reset_gpio, NULL);
192		if (error) {
193			dev_err(&client->dev,
194				"Unable to request GPIO pin %d.\n",
195				ts->reset_gpio);
196				return error;
197		}
198	}
199
200	st1232_ts_power(ts, true);
201
 
 
 
 
 
 
 
202	input_dev->name = "st1232-touchscreen";
203	input_dev->id.bustype = BUS_I2C;
204	input_dev->dev.parent = &client->dev;
205
206	__set_bit(EV_SYN, input_dev->evbit);
207	__set_bit(EV_KEY, input_dev->evbit);
208	__set_bit(EV_ABS, input_dev->evbit);
209
210	input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
211	input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
212	input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
 
 
 
 
 
 
 
 
 
 
 
213
214	error = devm_request_threaded_irq(&client->dev, client->irq,
215					  NULL, st1232_ts_irq_handler,
216					  IRQF_ONESHOT,
217					  client->name, ts);
218	if (error) {
219		dev_err(&client->dev, "Failed to register interrupt\n");
220		return error;
221	}
222
223	error = input_register_device(ts->input_dev);
224	if (error) {
225		dev_err(&client->dev, "Unable to register %s input device\n",
226			input_dev->name);
227		return error;
228	}
229
230	i2c_set_clientdata(client, ts);
231	device_init_wakeup(&client->dev, 1);
232
233	return 0;
234}
235
236static int st1232_ts_remove(struct i2c_client *client)
237{
238	struct st1232_ts_data *ts = i2c_get_clientdata(client);
239
240	device_init_wakeup(&client->dev, 0);
241	st1232_ts_power(ts, false);
242
243	return 0;
244}
245
246#ifdef CONFIG_PM_SLEEP
247static int st1232_ts_suspend(struct device *dev)
248{
249	struct i2c_client *client = to_i2c_client(dev);
250	struct st1232_ts_data *ts = i2c_get_clientdata(client);
251
252	if (device_may_wakeup(&client->dev)) {
253		enable_irq_wake(client->irq);
254	} else {
255		disable_irq(client->irq);
256		st1232_ts_power(ts, false);
257	}
258
259	return 0;
260}
261
262static int st1232_ts_resume(struct device *dev)
263{
264	struct i2c_client *client = to_i2c_client(dev);
265	struct st1232_ts_data *ts = i2c_get_clientdata(client);
266
267	if (device_may_wakeup(&client->dev)) {
268		disable_irq_wake(client->irq);
269	} else {
270		st1232_ts_power(ts, true);
271		enable_irq(client->irq);
272	}
273
274	return 0;
275}
276
277#endif
278
279static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
280			 st1232_ts_suspend, st1232_ts_resume);
281
282static const struct i2c_device_id st1232_ts_id[] = {
283	{ ST1232_TS_NAME, 0 },
 
284	{ }
285};
286MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
287
288#ifdef CONFIG_OF
289static const struct of_device_id st1232_ts_dt_ids[] = {
290	{ .compatible = "sitronix,st1232", },
 
291	{ }
292};
293MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
294#endif
295
296static struct i2c_driver st1232_ts_driver = {
297	.probe		= st1232_ts_probe,
298	.remove		= st1232_ts_remove,
299	.id_table	= st1232_ts_id,
300	.driver = {
301		.name	= ST1232_TS_NAME,
302		.owner	= THIS_MODULE,
303		.of_match_table = of_match_ptr(st1232_ts_dt_ids),
304		.pm	= &st1232_ts_pm_ops,
305	},
306};
307
308module_i2c_driver(st1232_ts_driver);
309
310MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
 
311MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
312MODULE_LICENSE("GPL");
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * ST1232 Touchscreen Controller Driver
  4 *
  5 * Copyright (C) 2010 Renesas Solutions Corp.
  6 *	Tony SIM <chinyeow.sim.xt@renesas.com>
  7 *
  8 * Using code from:
  9 *  - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
 10 *	Copyright (C) 2007 Google, Inc.
 
 
 
 
 
 
 
 
 
 11 */
 12
 13#include <linux/delay.h>
 14#include <linux/gpio/consumer.h>
 15#include <linux/i2c.h>
 16#include <linux/input.h>
 17#include <linux/input/mt.h>
 18#include <linux/input/touchscreen.h>
 19#include <linux/interrupt.h>
 20#include <linux/module.h>
 21#include <linux/of.h>
 
 22#include <linux/pm_qos.h>
 23#include <linux/slab.h>
 24#include <linux/types.h>
 
 25
 26#define ST1232_TS_NAME	"st1232-ts"
 27#define ST1633_TS_NAME	"st1633-ts"
 28
 29#define ST_TS_MAX_FINGERS	10
 30
 31struct st_chip_info {
 32	bool	have_z;
 33	u16	max_x;
 34	u16	max_y;
 35	u16	max_area;
 36	u16	max_fingers;
 37	u8	start_reg;
 
 
 
 38};
 39
 40struct st1232_ts_data {
 41	struct i2c_client *client;
 42	struct input_dev *input_dev;
 43	struct touchscreen_properties prop;
 44	struct dev_pm_qos_request low_latency_req;
 45	struct gpio_desc *reset_gpio;
 46	const struct st_chip_info *chip_info;
 47	int read_buf_len;
 48	u8 *read_buf;
 49};
 50
 51static int st1232_ts_read_data(struct st1232_ts_data *ts)
 52{
 
 53	struct i2c_client *client = ts->client;
 54	u8 start_reg = ts->chip_info->start_reg;
 55	struct i2c_msg msg[] = {
 56		{
 57			.addr	= client->addr,
 58			.len	= sizeof(start_reg),
 59			.buf	= &start_reg,
 60		},
 61		{
 62			.addr	= client->addr,
 63			.flags	= I2C_M_RD | I2C_M_DMA_SAFE,
 64			.len	= ts->read_buf_len,
 65			.buf	= ts->read_buf,
 66		}
 67	};
 68	int ret;
 69
 70	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
 71	if (ret != ARRAY_SIZE(msg))
 72		return ret < 0 ? ret : -EIO;
 
 
 
 
 
 
 
 
 73
 74	return 0;
 75}
 76
 77static int st1232_ts_parse_and_report(struct st1232_ts_data *ts)
 78{
 79	struct input_dev *input = ts->input_dev;
 80	struct input_mt_pos pos[ST_TS_MAX_FINGERS];
 81	u8 z[ST_TS_MAX_FINGERS];
 82	int slots[ST_TS_MAX_FINGERS];
 83	int n_contacts = 0;
 84	int i;
 85
 86	for (i = 0; i < ts->chip_info->max_fingers; i++) {
 87		u8 *buf = &ts->read_buf[i * 4];
 88
 89		if (buf[0] & BIT(7)) {
 90			unsigned int x = ((buf[0] & 0x70) << 4) | buf[1];
 91			unsigned int y = ((buf[0] & 0x07) << 8) | buf[2];
 92
 93			touchscreen_set_mt_pos(&pos[n_contacts],
 94					       &ts->prop, x, y);
 95
 96			/* st1232 includes a z-axis / touch strength */
 97			if (ts->chip_info->have_z)
 98				z[n_contacts] = ts->read_buf[i + 6];
 99
100			n_contacts++;
101		}
 
 
 
 
 
 
 
102	}
103
104	input_mt_assign_slots(input, slots, pos, n_contacts, 0);
105	for (i = 0; i < n_contacts; i++) {
106		input_mt_slot(input, slots[i]);
107		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
108		input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
109		input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
110		if (ts->chip_info->have_z)
111			input_report_abs(input, ABS_MT_TOUCH_MAJOR, z[i]);
112	}
113
114	input_mt_sync_frame(input);
115	input_sync(input);
116
117	return n_contacts;
118}
119
120static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
121{
122	struct st1232_ts_data *ts = dev_id;
123	int count;
124	int error;
125
126	error = st1232_ts_read_data(ts);
127	if (error)
128		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
129
130	count = st1232_ts_parse_and_report(ts);
131	if (!count) {
 
132		if (ts->low_latency_req.dev) {
133			dev_pm_qos_remove_request(&ts->low_latency_req);
134			ts->low_latency_req.dev = NULL;
135		}
136	} else if (!ts->low_latency_req.dev) {
137		/* First contact, request 100 us latency. */
138		dev_pm_qos_add_ancestor_request(&ts->client->dev,
139						&ts->low_latency_req,
140						DEV_PM_QOS_RESUME_LATENCY, 100);
141	}
142
143out:
 
 
 
144	return IRQ_HANDLED;
145}
146
147static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
148{
149	if (ts->reset_gpio)
150		gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
151}
152
153static void st1232_ts_power_off(void *data)
154{
155	st1232_ts_power(data, false);
156}
157
158static const struct st_chip_info st1232_chip_info = {
159	.have_z		= true,
160	.max_x		= 0x31f, /* 800 - 1 */
161	.max_y		= 0x1df, /* 480 -1 */
162	.max_area	= 0xff,
163	.max_fingers	= 2,
164	.start_reg	= 0x12,
165};
166
167static const struct st_chip_info st1633_chip_info = {
168	.have_z		= false,
169	.max_x		= 0x13f, /* 320 - 1 */
170	.max_y		= 0x1df, /* 480 -1 */
171	.max_area	= 0x00,
172	.max_fingers	= 5,
173	.start_reg	= 0x12,
174};
175
176static int st1232_ts_probe(struct i2c_client *client,
177			   const struct i2c_device_id *id)
178{
179	const struct st_chip_info *match;
180	struct st1232_ts_data *ts;
 
181	struct input_dev *input_dev;
182	int error;
183
184	match = device_get_match_data(&client->dev);
185	if (!match && id)
186		match = (const void *)id->driver_data;
187	if (!match) {
188		dev_err(&client->dev, "unknown device model\n");
189		return -ENODEV;
190	}
191
192	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
193		dev_err(&client->dev, "need I2C_FUNC_I2C\n");
194		return -EIO;
195	}
196
197	if (!client->irq) {
198		dev_err(&client->dev, "no IRQ?\n");
199		return -EINVAL;
200	}
201
202	ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
203	if (!ts)
204		return -ENOMEM;
205
206	ts->chip_info = match;
207
208	/* allocate a buffer according to the number of registers to read */
209	ts->read_buf_len = ts->chip_info->max_fingers * 4;
210	ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len, GFP_KERNEL);
211	if (!ts->read_buf)
212		return -ENOMEM;
213
214	input_dev = devm_input_allocate_device(&client->dev);
215	if (!input_dev)
216		return -ENOMEM;
217
218	ts->client = client;
219	ts->input_dev = input_dev;
220
221	ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL,
222						 GPIOD_OUT_HIGH);
223	if (IS_ERR(ts->reset_gpio)) {
224		error = PTR_ERR(ts->reset_gpio);
225		dev_err(&client->dev, "Unable to request GPIO pin: %d.\n",
226			error);
227		return error;
 
 
 
 
 
 
 
 
228	}
229
230	st1232_ts_power(ts, true);
231
232	error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts);
233	if (error) {
234		dev_err(&client->dev,
235			"Failed to install power off action: %d\n", error);
236		return error;
237	}
238
239	input_dev->name = "st1232-touchscreen";
240	input_dev->id.bustype = BUS_I2C;
 
241
242	if (ts->chip_info->have_z)
243		input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
244				     ts->chip_info->max_area, 0, 0);
245
246	input_set_abs_params(input_dev, ABS_MT_POSITION_X,
247			     0, ts->chip_info->max_x, 0, 0);
248	input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
249			     0, ts->chip_info->max_y, 0, 0);
250
251	touchscreen_parse_properties(input_dev, true, &ts->prop);
252
253	error = input_mt_init_slots(input_dev, ts->chip_info->max_fingers,
254				    INPUT_MT_DIRECT | INPUT_MT_TRACK |
255					INPUT_MT_DROP_UNUSED);
256	if (error) {
257		dev_err(&client->dev, "failed to initialize MT slots\n");
258		return error;
259	}
260
261	error = devm_request_threaded_irq(&client->dev, client->irq,
262					  NULL, st1232_ts_irq_handler,
263					  IRQF_ONESHOT,
264					  client->name, ts);
265	if (error) {
266		dev_err(&client->dev, "Failed to register interrupt\n");
267		return error;
268	}
269
270	error = input_register_device(ts->input_dev);
271	if (error) {
272		dev_err(&client->dev, "Unable to register %s input device\n",
273			input_dev->name);
274		return error;
275	}
276
277	i2c_set_clientdata(client, ts);
 
278
279	return 0;
280}
281
282static int __maybe_unused st1232_ts_suspend(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
283{
284	struct i2c_client *client = to_i2c_client(dev);
285	struct st1232_ts_data *ts = i2c_get_clientdata(client);
286
287	disable_irq(client->irq);
288
289	if (!device_may_wakeup(&client->dev))
 
290		st1232_ts_power(ts, false);
 
291
292	return 0;
293}
294
295static int __maybe_unused st1232_ts_resume(struct device *dev)
296{
297	struct i2c_client *client = to_i2c_client(dev);
298	struct st1232_ts_data *ts = i2c_get_clientdata(client);
299
300	if (!device_may_wakeup(&client->dev))
 
 
301		st1232_ts_power(ts, true);
302
303	enable_irq(client->irq);
304
305	return 0;
306}
307
 
 
308static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
309			 st1232_ts_suspend, st1232_ts_resume);
310
311static const struct i2c_device_id st1232_ts_id[] = {
312	{ ST1232_TS_NAME, (unsigned long)&st1232_chip_info },
313	{ ST1633_TS_NAME, (unsigned long)&st1633_chip_info },
314	{ }
315};
316MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
317
 
318static const struct of_device_id st1232_ts_dt_ids[] = {
319	{ .compatible = "sitronix,st1232", .data = &st1232_chip_info },
320	{ .compatible = "sitronix,st1633", .data = &st1633_chip_info },
321	{ }
322};
323MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
 
324
325static struct i2c_driver st1232_ts_driver = {
326	.probe		= st1232_ts_probe,
 
327	.id_table	= st1232_ts_id,
328	.driver = {
329		.name	= ST1232_TS_NAME,
330		.of_match_table = st1232_ts_dt_ids,
 
331		.pm	= &st1232_ts_pm_ops,
332	},
333};
334
335module_i2c_driver(st1232_ts_driver);
336
337MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
338MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@ginzinger.com>");
339MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
340MODULE_LICENSE("GPL v2");