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1/*
2 * Driver for ChipOne icn8318 i2c touchscreen controller
3 *
4 * Copyright (c) 2015 Red Hat Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * Red Hat authors:
12 * Hans de Goede <hdegoede@redhat.com>
13 */
14
15#include <linux/gpio/consumer.h>
16#include <linux/interrupt.h>
17#include <linux/i2c.h>
18#include <linux/input.h>
19#include <linux/input/mt.h>
20#include <linux/module.h>
21#include <linux/of.h>
22
23#define ICN8318_REG_POWER 4
24#define ICN8318_REG_TOUCHDATA 16
25
26#define ICN8318_POWER_ACTIVE 0
27#define ICN8318_POWER_MONITOR 1
28#define ICN8318_POWER_HIBERNATE 2
29
30#define ICN8318_MAX_TOUCHES 5
31
32struct icn8318_touch {
33 __u8 slot;
34 __be16 x;
35 __be16 y;
36 __u8 pressure; /* Seems more like finger width then pressure really */
37 __u8 event;
38/* The difference between 2 and 3 is unclear */
39#define ICN8318_EVENT_NO_DATA 1 /* No finger seen yet since wakeup */
40#define ICN8318_EVENT_UPDATE1 2 /* New or updated coordinates */
41#define ICN8318_EVENT_UPDATE2 3 /* New or updated coordinates */
42#define ICN8318_EVENT_END 4 /* Finger lifted */
43} __packed;
44
45struct icn8318_touch_data {
46 __u8 softbutton;
47 __u8 touch_count;
48 struct icn8318_touch touches[ICN8318_MAX_TOUCHES];
49} __packed;
50
51struct icn8318_data {
52 struct i2c_client *client;
53 struct input_dev *input;
54 struct gpio_desc *wake_gpio;
55 u32 max_x;
56 u32 max_y;
57 bool invert_x;
58 bool invert_y;
59 bool swap_x_y;
60};
61
62static int icn8318_read_touch_data(struct i2c_client *client,
63 struct icn8318_touch_data *touch_data)
64{
65 u8 reg = ICN8318_REG_TOUCHDATA;
66 struct i2c_msg msg[2] = {
67 {
68 .addr = client->addr,
69 .len = 1,
70 .buf = ®
71 },
72 {
73 .addr = client->addr,
74 .flags = I2C_M_RD,
75 .len = sizeof(struct icn8318_touch_data),
76 .buf = (u8 *)touch_data
77 }
78 };
79
80 return i2c_transfer(client->adapter, msg, 2);
81}
82
83static inline bool icn8318_touch_active(u8 event)
84{
85 return (event == ICN8318_EVENT_UPDATE1) ||
86 (event == ICN8318_EVENT_UPDATE2);
87}
88
89static irqreturn_t icn8318_irq(int irq, void *dev_id)
90{
91 struct icn8318_data *data = dev_id;
92 struct device *dev = &data->client->dev;
93 struct icn8318_touch_data touch_data;
94 int i, ret, x, y;
95
96 ret = icn8318_read_touch_data(data->client, &touch_data);
97 if (ret < 0) {
98 dev_err(dev, "Error reading touch data: %d\n", ret);
99 return IRQ_HANDLED;
100 }
101
102 if (touch_data.softbutton) {
103 /*
104 * Other data is invalid when a softbutton is pressed.
105 * This needs some extra devicetree bindings to map the icn8318
106 * softbutton codes to evdev codes. Currently no known devices
107 * use this.
108 */
109 return IRQ_HANDLED;
110 }
111
112 if (touch_data.touch_count > ICN8318_MAX_TOUCHES) {
113 dev_warn(dev, "Too much touches %d > %d\n",
114 touch_data.touch_count, ICN8318_MAX_TOUCHES);
115 touch_data.touch_count = ICN8318_MAX_TOUCHES;
116 }
117
118 for (i = 0; i < touch_data.touch_count; i++) {
119 struct icn8318_touch *touch = &touch_data.touches[i];
120 bool act = icn8318_touch_active(touch->event);
121
122 input_mt_slot(data->input, touch->slot);
123 input_mt_report_slot_state(data->input, MT_TOOL_FINGER, act);
124 if (!act)
125 continue;
126
127 x = be16_to_cpu(touch->x);
128 y = be16_to_cpu(touch->y);
129
130 if (data->invert_x)
131 x = data->max_x - x;
132
133 if (data->invert_y)
134 y = data->max_y - y;
135
136 if (!data->swap_x_y) {
137 input_event(data->input, EV_ABS, ABS_MT_POSITION_X, x);
138 input_event(data->input, EV_ABS, ABS_MT_POSITION_Y, y);
139 } else {
140 input_event(data->input, EV_ABS, ABS_MT_POSITION_X, y);
141 input_event(data->input, EV_ABS, ABS_MT_POSITION_Y, x);
142 }
143 }
144
145 input_mt_sync_frame(data->input);
146 input_sync(data->input);
147
148 return IRQ_HANDLED;
149}
150
151static int icn8318_start(struct input_dev *dev)
152{
153 struct icn8318_data *data = input_get_drvdata(dev);
154
155 enable_irq(data->client->irq);
156 gpiod_set_value_cansleep(data->wake_gpio, 1);
157
158 return 0;
159}
160
161static void icn8318_stop(struct input_dev *dev)
162{
163 struct icn8318_data *data = input_get_drvdata(dev);
164
165 disable_irq(data->client->irq);
166 i2c_smbus_write_byte_data(data->client, ICN8318_REG_POWER,
167 ICN8318_POWER_HIBERNATE);
168 gpiod_set_value_cansleep(data->wake_gpio, 0);
169}
170
171#ifdef CONFIG_PM_SLEEP
172static int icn8318_suspend(struct device *dev)
173{
174 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
175
176 mutex_lock(&data->input->mutex);
177 if (data->input->users)
178 icn8318_stop(data->input);
179 mutex_unlock(&data->input->mutex);
180
181 return 0;
182}
183
184static int icn8318_resume(struct device *dev)
185{
186 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
187
188 mutex_lock(&data->input->mutex);
189 if (data->input->users)
190 icn8318_start(data->input);
191 mutex_unlock(&data->input->mutex);
192
193 return 0;
194}
195#endif
196
197static SIMPLE_DEV_PM_OPS(icn8318_pm_ops, icn8318_suspend, icn8318_resume);
198
199static int icn8318_probe(struct i2c_client *client,
200 const struct i2c_device_id *id)
201{
202 struct device *dev = &client->dev;
203 struct device_node *np = dev->of_node;
204 struct icn8318_data *data;
205 struct input_dev *input;
206 u32 fuzz_x = 0, fuzz_y = 0;
207 int error;
208
209 if (!client->irq) {
210 dev_err(dev, "Error no irq specified\n");
211 return -EINVAL;
212 }
213
214 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
215 if (!data)
216 return -ENOMEM;
217
218 data->wake_gpio = devm_gpiod_get(dev, "wake", GPIOD_OUT_LOW);
219 if (IS_ERR(data->wake_gpio)) {
220 error = PTR_ERR(data->wake_gpio);
221 if (error != -EPROBE_DEFER)
222 dev_err(dev, "Error getting wake gpio: %d\n", error);
223 return error;
224 }
225
226 if (of_property_read_u32(np, "touchscreen-size-x", &data->max_x) ||
227 of_property_read_u32(np, "touchscreen-size-y", &data->max_y)) {
228 dev_err(dev, "Error touchscreen-size-x and/or -y missing\n");
229 return -EINVAL;
230 }
231
232 /* Optional */
233 of_property_read_u32(np, "touchscreen-fuzz-x", &fuzz_x);
234 of_property_read_u32(np, "touchscreen-fuzz-y", &fuzz_y);
235 data->invert_x = of_property_read_bool(np, "touchscreen-inverted-x");
236 data->invert_y = of_property_read_bool(np, "touchscreen-inverted-y");
237 data->swap_x_y = of_property_read_bool(np, "touchscreen-swapped-x-y");
238
239 input = devm_input_allocate_device(dev);
240 if (!input)
241 return -ENOMEM;
242
243 input->name = client->name;
244 input->id.bustype = BUS_I2C;
245 input->open = icn8318_start;
246 input->close = icn8318_stop;
247 input->dev.parent = dev;
248
249 if (!data->swap_x_y) {
250 input_set_abs_params(input, ABS_MT_POSITION_X, 0,
251 data->max_x, fuzz_x, 0);
252 input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
253 data->max_y, fuzz_y, 0);
254 } else {
255 input_set_abs_params(input, ABS_MT_POSITION_X, 0,
256 data->max_y, fuzz_y, 0);
257 input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
258 data->max_x, fuzz_x, 0);
259 }
260
261 error = input_mt_init_slots(input, ICN8318_MAX_TOUCHES,
262 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
263 if (error)
264 return error;
265
266 data->client = client;
267 data->input = input;
268 input_set_drvdata(input, data);
269
270 error = devm_request_threaded_irq(dev, client->irq, NULL, icn8318_irq,
271 IRQF_ONESHOT, client->name, data);
272 if (error) {
273 dev_err(dev, "Error requesting irq: %d\n", error);
274 return error;
275 }
276
277 /* Stop device till opened */
278 icn8318_stop(data->input);
279
280 error = input_register_device(input);
281 if (error)
282 return error;
283
284 i2c_set_clientdata(client, data);
285
286 return 0;
287}
288
289static const struct of_device_id icn8318_of_match[] = {
290 { .compatible = "chipone,icn8318" },
291 { }
292};
293MODULE_DEVICE_TABLE(of, icn8318_of_match);
294
295/* This is useless for OF-enabled devices, but it is needed by I2C subsystem */
296static const struct i2c_device_id icn8318_i2c_id[] = {
297 { },
298};
299MODULE_DEVICE_TABLE(i2c, icn8318_i2c_id);
300
301static struct i2c_driver icn8318_driver = {
302 .driver = {
303 .name = "chipone_icn8318",
304 .pm = &icn8318_pm_ops,
305 .of_match_table = icn8318_of_match,
306 },
307 .probe = icn8318_probe,
308 .id_table = icn8318_i2c_id,
309};
310
311module_i2c_driver(icn8318_driver);
312
313MODULE_DESCRIPTION("ChipOne icn8318 I2C Touchscreen Driver");
314MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
315MODULE_LICENSE("GPL");
1/*
2 * Driver for ChipOne icn8318 i2c touchscreen controller
3 *
4 * Copyright (c) 2015 Red Hat Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * Red Hat authors:
12 * Hans de Goede <hdegoede@redhat.com>
13 */
14
15#include <linux/gpio/consumer.h>
16#include <linux/interrupt.h>
17#include <linux/i2c.h>
18#include <linux/input.h>
19#include <linux/input/mt.h>
20#include <linux/input/touchscreen.h>
21#include <linux/module.h>
22#include <linux/of.h>
23
24#define ICN8318_REG_POWER 4
25#define ICN8318_REG_TOUCHDATA 16
26
27#define ICN8318_POWER_ACTIVE 0
28#define ICN8318_POWER_MONITOR 1
29#define ICN8318_POWER_HIBERNATE 2
30
31#define ICN8318_MAX_TOUCHES 5
32
33struct icn8318_touch {
34 __u8 slot;
35 __be16 x;
36 __be16 y;
37 __u8 pressure; /* Seems more like finger width then pressure really */
38 __u8 event;
39/* The difference between 2 and 3 is unclear */
40#define ICN8318_EVENT_NO_DATA 1 /* No finger seen yet since wakeup */
41#define ICN8318_EVENT_UPDATE1 2 /* New or updated coordinates */
42#define ICN8318_EVENT_UPDATE2 3 /* New or updated coordinates */
43#define ICN8318_EVENT_END 4 /* Finger lifted */
44} __packed;
45
46struct icn8318_touch_data {
47 __u8 softbutton;
48 __u8 touch_count;
49 struct icn8318_touch touches[ICN8318_MAX_TOUCHES];
50} __packed;
51
52struct icn8318_data {
53 struct i2c_client *client;
54 struct input_dev *input;
55 struct gpio_desc *wake_gpio;
56 struct touchscreen_properties prop;
57};
58
59static int icn8318_read_touch_data(struct i2c_client *client,
60 struct icn8318_touch_data *touch_data)
61{
62 u8 reg = ICN8318_REG_TOUCHDATA;
63 struct i2c_msg msg[2] = {
64 {
65 .addr = client->addr,
66 .len = 1,
67 .buf = ®
68 },
69 {
70 .addr = client->addr,
71 .flags = I2C_M_RD,
72 .len = sizeof(struct icn8318_touch_data),
73 .buf = (u8 *)touch_data
74 }
75 };
76
77 return i2c_transfer(client->adapter, msg, 2);
78}
79
80static inline bool icn8318_touch_active(u8 event)
81{
82 return (event == ICN8318_EVENT_UPDATE1) ||
83 (event == ICN8318_EVENT_UPDATE2);
84}
85
86static irqreturn_t icn8318_irq(int irq, void *dev_id)
87{
88 struct icn8318_data *data = dev_id;
89 struct device *dev = &data->client->dev;
90 struct icn8318_touch_data touch_data;
91 int i, ret;
92
93 ret = icn8318_read_touch_data(data->client, &touch_data);
94 if (ret < 0) {
95 dev_err(dev, "Error reading touch data: %d\n", ret);
96 return IRQ_HANDLED;
97 }
98
99 if (touch_data.softbutton) {
100 /*
101 * Other data is invalid when a softbutton is pressed.
102 * This needs some extra devicetree bindings to map the icn8318
103 * softbutton codes to evdev codes. Currently no known devices
104 * use this.
105 */
106 return IRQ_HANDLED;
107 }
108
109 if (touch_data.touch_count > ICN8318_MAX_TOUCHES) {
110 dev_warn(dev, "Too much touches %d > %d\n",
111 touch_data.touch_count, ICN8318_MAX_TOUCHES);
112 touch_data.touch_count = ICN8318_MAX_TOUCHES;
113 }
114
115 for (i = 0; i < touch_data.touch_count; i++) {
116 struct icn8318_touch *touch = &touch_data.touches[i];
117 bool act = icn8318_touch_active(touch->event);
118
119 input_mt_slot(data->input, touch->slot);
120 input_mt_report_slot_state(data->input, MT_TOOL_FINGER, act);
121 if (!act)
122 continue;
123
124 touchscreen_report_pos(data->input, &data->prop,
125 be16_to_cpu(touch->x),
126 be16_to_cpu(touch->y), true);
127 }
128
129 input_mt_sync_frame(data->input);
130 input_sync(data->input);
131
132 return IRQ_HANDLED;
133}
134
135static int icn8318_start(struct input_dev *dev)
136{
137 struct icn8318_data *data = input_get_drvdata(dev);
138
139 enable_irq(data->client->irq);
140 gpiod_set_value_cansleep(data->wake_gpio, 1);
141
142 return 0;
143}
144
145static void icn8318_stop(struct input_dev *dev)
146{
147 struct icn8318_data *data = input_get_drvdata(dev);
148
149 disable_irq(data->client->irq);
150 i2c_smbus_write_byte_data(data->client, ICN8318_REG_POWER,
151 ICN8318_POWER_HIBERNATE);
152 gpiod_set_value_cansleep(data->wake_gpio, 0);
153}
154
155#ifdef CONFIG_PM_SLEEP
156static int icn8318_suspend(struct device *dev)
157{
158 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
159
160 mutex_lock(&data->input->mutex);
161 if (data->input->users)
162 icn8318_stop(data->input);
163 mutex_unlock(&data->input->mutex);
164
165 return 0;
166}
167
168static int icn8318_resume(struct device *dev)
169{
170 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
171
172 mutex_lock(&data->input->mutex);
173 if (data->input->users)
174 icn8318_start(data->input);
175 mutex_unlock(&data->input->mutex);
176
177 return 0;
178}
179#endif
180
181static SIMPLE_DEV_PM_OPS(icn8318_pm_ops, icn8318_suspend, icn8318_resume);
182
183static int icn8318_probe(struct i2c_client *client,
184 const struct i2c_device_id *id)
185{
186 struct device *dev = &client->dev;
187 struct icn8318_data *data;
188 struct input_dev *input;
189 int error;
190
191 if (!client->irq) {
192 dev_err(dev, "Error no irq specified\n");
193 return -EINVAL;
194 }
195
196 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
197 if (!data)
198 return -ENOMEM;
199
200 data->wake_gpio = devm_gpiod_get(dev, "wake", GPIOD_OUT_LOW);
201 if (IS_ERR(data->wake_gpio)) {
202 error = PTR_ERR(data->wake_gpio);
203 if (error != -EPROBE_DEFER)
204 dev_err(dev, "Error getting wake gpio: %d\n", error);
205 return error;
206 }
207
208 input = devm_input_allocate_device(dev);
209 if (!input)
210 return -ENOMEM;
211
212 input->name = client->name;
213 input->id.bustype = BUS_I2C;
214 input->open = icn8318_start;
215 input->close = icn8318_stop;
216 input->dev.parent = dev;
217
218 input_set_capability(input, EV_ABS, ABS_MT_POSITION_X);
219 input_set_capability(input, EV_ABS, ABS_MT_POSITION_Y);
220
221 touchscreen_parse_properties(input, true, &data->prop);
222 if (!input_abs_get_max(input, ABS_MT_POSITION_X) ||
223 !input_abs_get_max(input, ABS_MT_POSITION_Y)) {
224 dev_err(dev, "Error touchscreen-size-x and/or -y missing\n");
225 return -EINVAL;
226 }
227
228 error = input_mt_init_slots(input, ICN8318_MAX_TOUCHES,
229 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
230 if (error)
231 return error;
232
233 data->client = client;
234 data->input = input;
235 input_set_drvdata(input, data);
236
237 error = devm_request_threaded_irq(dev, client->irq, NULL, icn8318_irq,
238 IRQF_ONESHOT, client->name, data);
239 if (error) {
240 dev_err(dev, "Error requesting irq: %d\n", error);
241 return error;
242 }
243
244 /* Stop device till opened */
245 icn8318_stop(data->input);
246
247 error = input_register_device(input);
248 if (error)
249 return error;
250
251 i2c_set_clientdata(client, data);
252
253 return 0;
254}
255
256static const struct of_device_id icn8318_of_match[] = {
257 { .compatible = "chipone,icn8318" },
258 { }
259};
260MODULE_DEVICE_TABLE(of, icn8318_of_match);
261
262/* This is useless for OF-enabled devices, but it is needed by I2C subsystem */
263static const struct i2c_device_id icn8318_i2c_id[] = {
264 { },
265};
266MODULE_DEVICE_TABLE(i2c, icn8318_i2c_id);
267
268static struct i2c_driver icn8318_driver = {
269 .driver = {
270 .name = "chipone_icn8318",
271 .pm = &icn8318_pm_ops,
272 .of_match_table = icn8318_of_match,
273 },
274 .probe = icn8318_probe,
275 .id_table = icn8318_i2c_id,
276};
277
278module_i2c_driver(icn8318_driver);
279
280MODULE_DESCRIPTION("ChipOne icn8318 I2C Touchscreen Driver");
281MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
282MODULE_LICENSE("GPL");