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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 REG_STATUS 0x01 /* Device Status | Error Code */
30
31#define STATUS_NORMAL 0x00
32#define STATUS_INIT 0x01
33#define STATUS_ERROR 0x02
34#define STATUS_AUTO_TUNING 0x03
35#define STATUS_IDLE 0x04
36#define STATUS_POWER_DOWN 0x05
37
38#define ERROR_NONE 0x00
39#define ERROR_INVALID_ADDRESS 0x10
40#define ERROR_INVALID_VALUE 0x20
41#define ERROR_INVALID_PLATFORM 0x30
42
43#define REG_XY_RESOLUTION 0x04
44#define REG_XY_COORDINATES 0x12
45#define ST_TS_MAX_FINGERS 10
46
47struct st_chip_info {
48 bool have_z;
49 u16 max_area;
50 u16 max_fingers;
51};
52
53struct st1232_ts_data {
54 struct i2c_client *client;
55 struct input_dev *input_dev;
56 struct touchscreen_properties prop;
57 struct dev_pm_qos_request low_latency_req;
58 struct gpio_desc *reset_gpio;
59 const struct st_chip_info *chip_info;
60 int read_buf_len;
61 u8 *read_buf;
62};
63
64static int st1232_ts_read_data(struct st1232_ts_data *ts, u8 reg,
65 unsigned int n)
66{
67 struct i2c_client *client = ts->client;
68 struct i2c_msg msg[] = {
69 {
70 .addr = client->addr,
71 .len = sizeof(reg),
72 .buf = ®,
73 },
74 {
75 .addr = client->addr,
76 .flags = I2C_M_RD | I2C_M_DMA_SAFE,
77 .len = n,
78 .buf = ts->read_buf,
79 }
80 };
81 int ret;
82
83 ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
84 if (ret != ARRAY_SIZE(msg))
85 return ret < 0 ? ret : -EIO;
86
87 return 0;
88}
89
90static int st1232_ts_wait_ready(struct st1232_ts_data *ts)
91{
92 unsigned int retries;
93 int error;
94
95 for (retries = 100; retries; retries--) {
96 error = st1232_ts_read_data(ts, REG_STATUS, 1);
97 if (!error) {
98 switch (ts->read_buf[0]) {
99 case STATUS_NORMAL | ERROR_NONE:
100 case STATUS_IDLE | ERROR_NONE:
101 return 0;
102 }
103 }
104
105 usleep_range(1000, 2000);
106 }
107
108 return -ENXIO;
109}
110
111static int st1232_ts_read_resolution(struct st1232_ts_data *ts, u16 *max_x,
112 u16 *max_y)
113{
114 u8 *buf;
115 int error;
116
117 /* select resolution register */
118 error = st1232_ts_read_data(ts, REG_XY_RESOLUTION, 3);
119 if (error)
120 return error;
121
122 buf = ts->read_buf;
123
124 *max_x = (((buf[0] & 0x0070) << 4) | buf[1]) - 1;
125 *max_y = (((buf[0] & 0x0007) << 8) | buf[2]) - 1;
126
127 return 0;
128}
129
130static int st1232_ts_parse_and_report(struct st1232_ts_data *ts)
131{
132 struct input_dev *input = ts->input_dev;
133 struct input_mt_pos pos[ST_TS_MAX_FINGERS];
134 u8 z[ST_TS_MAX_FINGERS];
135 int slots[ST_TS_MAX_FINGERS];
136 int n_contacts = 0;
137 int i;
138
139 for (i = 0; i < ts->chip_info->max_fingers; i++) {
140 u8 *buf = &ts->read_buf[i * 4];
141
142 if (buf[0] & BIT(7)) {
143 unsigned int x = ((buf[0] & 0x70) << 4) | buf[1];
144 unsigned int y = ((buf[0] & 0x07) << 8) | buf[2];
145
146 touchscreen_set_mt_pos(&pos[n_contacts],
147 &ts->prop, x, y);
148
149 /* st1232 includes a z-axis / touch strength */
150 if (ts->chip_info->have_z)
151 z[n_contacts] = ts->read_buf[i + 6];
152
153 n_contacts++;
154 }
155 }
156
157 input_mt_assign_slots(input, slots, pos, n_contacts, 0);
158 for (i = 0; i < n_contacts; i++) {
159 input_mt_slot(input, slots[i]);
160 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
161 input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
162 input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
163 if (ts->chip_info->have_z)
164 input_report_abs(input, ABS_MT_TOUCH_MAJOR, z[i]);
165 }
166
167 input_mt_sync_frame(input);
168 input_sync(input);
169
170 return n_contacts;
171}
172
173static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
174{
175 struct st1232_ts_data *ts = dev_id;
176 int count;
177 int error;
178
179 error = st1232_ts_read_data(ts, REG_XY_COORDINATES, ts->read_buf_len);
180 if (error)
181 goto out;
182
183 count = st1232_ts_parse_and_report(ts);
184 if (!count) {
185 if (ts->low_latency_req.dev) {
186 dev_pm_qos_remove_request(&ts->low_latency_req);
187 ts->low_latency_req.dev = NULL;
188 }
189 } else if (!ts->low_latency_req.dev) {
190 /* First contact, request 100 us latency. */
191 dev_pm_qos_add_ancestor_request(&ts->client->dev,
192 &ts->low_latency_req,
193 DEV_PM_QOS_RESUME_LATENCY, 100);
194 }
195
196out:
197 return IRQ_HANDLED;
198}
199
200static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
201{
202 if (ts->reset_gpio)
203 gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
204}
205
206static void st1232_ts_power_off(void *data)
207{
208 st1232_ts_power(data, false);
209}
210
211static const struct st_chip_info st1232_chip_info = {
212 .have_z = true,
213 .max_area = 0xff,
214 .max_fingers = 2,
215};
216
217static const struct st_chip_info st1633_chip_info = {
218 .have_z = false,
219 .max_area = 0x00,
220 .max_fingers = 5,
221};
222
223static int st1232_ts_probe(struct i2c_client *client)
224{
225 const struct i2c_device_id *id = i2c_client_get_device_id(client);
226 const struct st_chip_info *match;
227 struct st1232_ts_data *ts;
228 struct input_dev *input_dev;
229 u16 max_x, max_y;
230 int error;
231
232 match = device_get_match_data(&client->dev);
233 if (!match && id)
234 match = (const void *)id->driver_data;
235 if (!match) {
236 dev_err(&client->dev, "unknown device model\n");
237 return -ENODEV;
238 }
239
240 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
241 dev_err(&client->dev, "need I2C_FUNC_I2C\n");
242 return -EIO;
243 }
244
245 if (!client->irq) {
246 dev_err(&client->dev, "no IRQ?\n");
247 return -EINVAL;
248 }
249
250 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
251 if (!ts)
252 return -ENOMEM;
253
254 ts->chip_info = match;
255
256 /* allocate a buffer according to the number of registers to read */
257 ts->read_buf_len = ts->chip_info->max_fingers * 4;
258 ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len, GFP_KERNEL);
259 if (!ts->read_buf)
260 return -ENOMEM;
261
262 input_dev = devm_input_allocate_device(&client->dev);
263 if (!input_dev)
264 return -ENOMEM;
265
266 ts->client = client;
267 ts->input_dev = input_dev;
268
269 ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL,
270 GPIOD_OUT_HIGH);
271 if (IS_ERR(ts->reset_gpio)) {
272 error = PTR_ERR(ts->reset_gpio);
273 dev_err(&client->dev, "Unable to request GPIO pin: %d.\n",
274 error);
275 return error;
276 }
277
278 st1232_ts_power(ts, true);
279
280 error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts);
281 if (error) {
282 dev_err(&client->dev,
283 "Failed to install power off action: %d\n", error);
284 return error;
285 }
286
287 input_dev->name = "st1232-touchscreen";
288 input_dev->id.bustype = BUS_I2C;
289
290 /* Wait until device is ready */
291 error = st1232_ts_wait_ready(ts);
292 if (error)
293 return error;
294
295 /* Read resolution from the chip */
296 error = st1232_ts_read_resolution(ts, &max_x, &max_y);
297 if (error) {
298 dev_err(&client->dev,
299 "Failed to read resolution: %d\n", error);
300 return error;
301 }
302
303 if (ts->chip_info->have_z)
304 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
305 ts->chip_info->max_area, 0, 0);
306
307 input_set_abs_params(input_dev, ABS_MT_POSITION_X,
308 0, max_x, 0, 0);
309 input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
310 0, max_y, 0, 0);
311
312 touchscreen_parse_properties(input_dev, true, &ts->prop);
313
314 error = input_mt_init_slots(input_dev, ts->chip_info->max_fingers,
315 INPUT_MT_DIRECT | INPUT_MT_TRACK |
316 INPUT_MT_DROP_UNUSED);
317 if (error) {
318 dev_err(&client->dev, "failed to initialize MT slots\n");
319 return error;
320 }
321
322 error = devm_request_threaded_irq(&client->dev, client->irq,
323 NULL, st1232_ts_irq_handler,
324 IRQF_ONESHOT,
325 client->name, ts);
326 if (error) {
327 dev_err(&client->dev, "Failed to register interrupt\n");
328 return error;
329 }
330
331 error = input_register_device(ts->input_dev);
332 if (error) {
333 dev_err(&client->dev, "Unable to register %s input device\n",
334 input_dev->name);
335 return error;
336 }
337
338 i2c_set_clientdata(client, ts);
339
340 return 0;
341}
342
343static int __maybe_unused st1232_ts_suspend(struct device *dev)
344{
345 struct i2c_client *client = to_i2c_client(dev);
346 struct st1232_ts_data *ts = i2c_get_clientdata(client);
347
348 disable_irq(client->irq);
349
350 if (!device_may_wakeup(&client->dev))
351 st1232_ts_power(ts, false);
352
353 return 0;
354}
355
356static int __maybe_unused st1232_ts_resume(struct device *dev)
357{
358 struct i2c_client *client = to_i2c_client(dev);
359 struct st1232_ts_data *ts = i2c_get_clientdata(client);
360
361 if (!device_may_wakeup(&client->dev))
362 st1232_ts_power(ts, true);
363
364 enable_irq(client->irq);
365
366 return 0;
367}
368
369static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
370 st1232_ts_suspend, st1232_ts_resume);
371
372static const struct i2c_device_id st1232_ts_id[] = {
373 { ST1232_TS_NAME, (unsigned long)&st1232_chip_info },
374 { ST1633_TS_NAME, (unsigned long)&st1633_chip_info },
375 { }
376};
377MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
378
379static const struct of_device_id st1232_ts_dt_ids[] = {
380 { .compatible = "sitronix,st1232", .data = &st1232_chip_info },
381 { .compatible = "sitronix,st1633", .data = &st1633_chip_info },
382 { }
383};
384MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
385
386static struct i2c_driver st1232_ts_driver = {
387 .probe_new = st1232_ts_probe,
388 .id_table = st1232_ts_id,
389 .driver = {
390 .name = ST1232_TS_NAME,
391 .of_match_table = st1232_ts_dt_ids,
392 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
393 .pm = &st1232_ts_pm_ops,
394 },
395};
396
397module_i2c_driver(st1232_ts_driver);
398
399MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
400MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@ginzinger.com>");
401MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
402MODULE_LICENSE("GPL v2");
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
33#define ST1232_TS_NAME "st1232-ts"
34
35#define MIN_X 0x00
36#define MIN_Y 0x00
37#define MAX_X 0x31f /* (800 - 1) */
38#define MAX_Y 0x1df /* (480 - 1) */
39#define MAX_AREA 0xff
40#define MAX_FINGERS 2
41
42struct st1232_ts_finger {
43 u16 x;
44 u16 y;
45 u8 t;
46 bool is_valid;
47};
48
49struct st1232_ts_data {
50 struct i2c_client *client;
51 struct input_dev *input_dev;
52 struct st1232_ts_finger finger[MAX_FINGERS];
53 struct dev_pm_qos_request low_latency_req;
54 int reset_gpio;
55};
56
57static int st1232_ts_read_data(struct st1232_ts_data *ts)
58{
59 struct st1232_ts_finger *finger = ts->finger;
60 struct i2c_client *client = ts->client;
61 struct i2c_msg msg[2];
62 int error;
63 u8 start_reg;
64 u8 buf[10];
65
66 /* read touchscreen data from ST1232 */
67 msg[0].addr = client->addr;
68 msg[0].flags = 0;
69 msg[0].len = 1;
70 msg[0].buf = &start_reg;
71 start_reg = 0x10;
72
73 msg[1].addr = ts->client->addr;
74 msg[1].flags = I2C_M_RD;
75 msg[1].len = sizeof(buf);
76 msg[1].buf = buf;
77
78 error = i2c_transfer(client->adapter, msg, 2);
79 if (error < 0)
80 return error;
81
82 /* get "valid" bits */
83 finger[0].is_valid = buf[2] >> 7;
84 finger[1].is_valid = buf[5] >> 7;
85
86 /* get xy coordinate */
87 if (finger[0].is_valid) {
88 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
89 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
90 finger[0].t = buf[8];
91 }
92
93 if (finger[1].is_valid) {
94 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
95 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
96 finger[1].t = buf[9];
97 }
98
99 return 0;
100}
101
102static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
103{
104 struct st1232_ts_data *ts = dev_id;
105 struct st1232_ts_finger *finger = ts->finger;
106 struct input_dev *input_dev = ts->input_dev;
107 int count = 0;
108 int i, ret;
109
110 ret = st1232_ts_read_data(ts);
111 if (ret < 0)
112 goto end;
113
114 /* multi touch protocol */
115 for (i = 0; i < MAX_FINGERS; i++) {
116 if (!finger[i].is_valid)
117 continue;
118
119 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
120 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
121 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
122 input_mt_sync(input_dev);
123 count++;
124 }
125
126 /* SYN_MT_REPORT only if no contact */
127 if (!count) {
128 input_mt_sync(input_dev);
129 if (ts->low_latency_req.dev) {
130 dev_pm_qos_remove_request(&ts->low_latency_req);
131 ts->low_latency_req.dev = NULL;
132 }
133 } else if (!ts->low_latency_req.dev) {
134 /* First contact, request 100 us latency. */
135 dev_pm_qos_add_ancestor_request(&ts->client->dev,
136 &ts->low_latency_req,
137 DEV_PM_QOS_RESUME_LATENCY, 100);
138 }
139
140 /* SYN_REPORT */
141 input_sync(input_dev);
142
143end:
144 return IRQ_HANDLED;
145}
146
147static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
148{
149 if (gpio_is_valid(ts->reset_gpio))
150 gpio_direction_output(ts->reset_gpio, poweron);
151}
152
153static int st1232_ts_probe(struct i2c_client *client,
154 const struct i2c_device_id *id)
155{
156 struct st1232_ts_data *ts;
157 struct input_dev *input_dev;
158 int error;
159
160 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
161 dev_err(&client->dev, "need I2C_FUNC_I2C\n");
162 return -EIO;
163 }
164
165 if (!client->irq) {
166 dev_err(&client->dev, "no IRQ?\n");
167 return -EINVAL;
168 }
169
170 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
171 if (!ts)
172 return -ENOMEM;
173
174 input_dev = devm_input_allocate_device(&client->dev);
175 if (!input_dev)
176 return -ENOMEM;
177
178 ts->client = client;
179 ts->input_dev = input_dev;
180
181 ts->reset_gpio = of_get_gpio(client->dev.of_node, 0);
182 if (gpio_is_valid(ts->reset_gpio)) {
183 error = devm_gpio_request(&client->dev, ts->reset_gpio, NULL);
184 if (error) {
185 dev_err(&client->dev,
186 "Unable to request GPIO pin %d.\n",
187 ts->reset_gpio);
188 return error;
189 }
190 }
191
192 st1232_ts_power(ts, true);
193
194 input_dev->name = "st1232-touchscreen";
195 input_dev->id.bustype = BUS_I2C;
196 input_dev->dev.parent = &client->dev;
197
198 __set_bit(EV_SYN, input_dev->evbit);
199 __set_bit(EV_KEY, input_dev->evbit);
200 __set_bit(EV_ABS, input_dev->evbit);
201
202 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
203 input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
204 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
205
206 error = devm_request_threaded_irq(&client->dev, client->irq,
207 NULL, st1232_ts_irq_handler,
208 IRQF_ONESHOT,
209 client->name, ts);
210 if (error) {
211 dev_err(&client->dev, "Failed to register interrupt\n");
212 return error;
213 }
214
215 error = input_register_device(ts->input_dev);
216 if (error) {
217 dev_err(&client->dev, "Unable to register %s input device\n",
218 input_dev->name);
219 return error;
220 }
221
222 i2c_set_clientdata(client, ts);
223 device_init_wakeup(&client->dev, 1);
224
225 return 0;
226}
227
228static int st1232_ts_remove(struct i2c_client *client)
229{
230 struct st1232_ts_data *ts = i2c_get_clientdata(client);
231
232 st1232_ts_power(ts, false);
233
234 return 0;
235}
236
237static int __maybe_unused st1232_ts_suspend(struct device *dev)
238{
239 struct i2c_client *client = to_i2c_client(dev);
240 struct st1232_ts_data *ts = i2c_get_clientdata(client);
241
242 if (device_may_wakeup(&client->dev)) {
243 enable_irq_wake(client->irq);
244 } else {
245 disable_irq(client->irq);
246 st1232_ts_power(ts, false);
247 }
248
249 return 0;
250}
251
252static int __maybe_unused st1232_ts_resume(struct device *dev)
253{
254 struct i2c_client *client = to_i2c_client(dev);
255 struct st1232_ts_data *ts = i2c_get_clientdata(client);
256
257 if (device_may_wakeup(&client->dev)) {
258 disable_irq_wake(client->irq);
259 } else {
260 st1232_ts_power(ts, true);
261 enable_irq(client->irq);
262 }
263
264 return 0;
265}
266
267static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
268 st1232_ts_suspend, st1232_ts_resume);
269
270static const struct i2c_device_id st1232_ts_id[] = {
271 { ST1232_TS_NAME, 0 },
272 { }
273};
274MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
275
276static const struct of_device_id st1232_ts_dt_ids[] = {
277 { .compatible = "sitronix,st1232", },
278 { }
279};
280MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
281
282static struct i2c_driver st1232_ts_driver = {
283 .probe = st1232_ts_probe,
284 .remove = st1232_ts_remove,
285 .id_table = st1232_ts_id,
286 .driver = {
287 .name = ST1232_TS_NAME,
288 .of_match_table = st1232_ts_dt_ids,
289 .pm = &st1232_ts_pm_ops,
290 },
291};
292
293module_i2c_driver(st1232_ts_driver);
294
295MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
296MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
297MODULE_LICENSE("GPL");