Linux 5.3-rc8
[sfrench/cifs-2.6.git] / drivers / input / touchscreen / zet6223.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2016, Jelle van der Waa <jelle@vdwaa.nl>
4  */
5
6 #include <linux/delay.h>
7 #include <linux/i2c.h>
8 #include <linux/input.h>
9 #include <linux/input/mt.h>
10 #include <linux/input/touchscreen.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/regulator/consumer.h>
14 #include <asm/unaligned.h>
15
16 #define ZET6223_MAX_FINGERS             16
17 #define ZET6223_MAX_PKT_SIZE            (3 + 4 * ZET6223_MAX_FINGERS)
18
19 #define ZET6223_CMD_INFO                0xB2
20 #define ZET6223_CMD_INFO_LENGTH         17
21 #define ZET6223_VALID_PACKET            0x3c
22
23 #define ZET6223_POWER_ON_DELAY_MSEC     30
24
25 struct zet6223_ts {
26         struct i2c_client *client;
27         struct input_dev *input;
28         struct regulator *vcc;
29         struct regulator *vio;
30         struct touchscreen_properties prop;
31         struct regulator_bulk_data supplies[2];
32         u16 max_x;
33         u16 max_y;
34         u8 fingernum;
35 };
36
37 static int zet6223_start(struct input_dev *dev)
38 {
39         struct zet6223_ts *ts = input_get_drvdata(dev);
40
41         enable_irq(ts->client->irq);
42
43         return 0;
44 }
45
46 static void zet6223_stop(struct input_dev *dev)
47 {
48         struct zet6223_ts *ts = input_get_drvdata(dev);
49
50         disable_irq(ts->client->irq);
51 }
52
53 static irqreturn_t zet6223_irq(int irq, void *dev_id)
54 {
55         struct zet6223_ts *ts = dev_id;
56         u16 finger_bits;
57
58         /*
59          * First 3 bytes are an identifier, two bytes of finger data.
60          * X, Y data per finger is 4 bytes.
61          */
62         u8 bufsize = 3 + 4 * ts->fingernum;
63         u8 buf[ZET6223_MAX_PKT_SIZE];
64         int i;
65         int ret;
66         int error;
67
68         ret = i2c_master_recv(ts->client, buf, bufsize);
69         if (ret != bufsize) {
70                 error = ret < 0 ? ret : -EIO;
71                 dev_err_ratelimited(&ts->client->dev,
72                                     "Error reading input data: %d\n", error);
73                 return IRQ_HANDLED;
74         }
75
76         if (buf[0] != ZET6223_VALID_PACKET)
77                 return IRQ_HANDLED;
78
79         finger_bits = get_unaligned_be16(buf + 1);
80         for (i = 0; i < ts->fingernum; i++) {
81                 if (!(finger_bits & BIT(15 - i)))
82                         continue;
83
84                 input_mt_slot(ts->input, i);
85                 input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
86                 input_event(ts->input, EV_ABS, ABS_MT_POSITION_X,
87                                 ((buf[i + 3] >> 4) << 8) + buf[i + 4]);
88                 input_event(ts->input, EV_ABS, ABS_MT_POSITION_Y,
89                                 ((buf[i + 3] & 0xF) << 8) + buf[i + 5]);
90         }
91
92         input_mt_sync_frame(ts->input);
93         input_sync(ts->input);
94
95         return IRQ_HANDLED;
96 }
97
98 static void zet6223_power_off(void *_ts)
99 {
100         struct zet6223_ts *ts = _ts;
101
102         regulator_bulk_disable(ARRAY_SIZE(ts->supplies), ts->supplies);
103 }
104
105 static int zet6223_power_on(struct zet6223_ts *ts)
106 {
107         struct device *dev = &ts->client->dev;
108         int error;
109
110         ts->supplies[0].supply = "vio";
111         ts->supplies[1].supply = "vcc";
112
113         error = devm_regulator_bulk_get(dev, ARRAY_SIZE(ts->supplies),
114                                         ts->supplies);
115         if (error)
116                 return error;
117
118         error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies), ts->supplies);
119         if (error)
120                 return error;
121
122         msleep(ZET6223_POWER_ON_DELAY_MSEC);
123
124         error = devm_add_action_or_reset(dev, zet6223_power_off, ts);
125         if (error) {
126                 dev_err(dev, "failed to install poweroff action: %d\n", error);
127                 return error;
128         }
129
130         return 0;
131 }
132
133 static int zet6223_query_device(struct zet6223_ts *ts)
134 {
135         u8 buf[ZET6223_CMD_INFO_LENGTH];
136         u8 cmd = ZET6223_CMD_INFO;
137         int ret;
138         int error;
139
140         ret = i2c_master_send(ts->client, &cmd, sizeof(cmd));
141         if (ret != sizeof(cmd)) {
142                 error = ret < 0 ? ret : -EIO;
143                 dev_err(&ts->client->dev,
144                         "touchpanel info cmd failed: %d\n", error);
145                 return error;
146         }
147
148         ret = i2c_master_recv(ts->client, buf, sizeof(buf));
149         if (ret != sizeof(buf)) {
150                 error = ret < 0 ? ret : -EIO;
151                 dev_err(&ts->client->dev,
152                         "failed to retrieve touchpanel info: %d\n", error);
153                 return error;
154         }
155
156         ts->fingernum = buf[15] & 0x7F;
157         if (ts->fingernum > ZET6223_MAX_FINGERS) {
158                 dev_warn(&ts->client->dev,
159                          "touchpanel reports %d fingers, limiting to %d\n",
160                          ts->fingernum, ZET6223_MAX_FINGERS);
161                 ts->fingernum = ZET6223_MAX_FINGERS;
162         }
163
164         ts->max_x = get_unaligned_le16(&buf[8]);
165         ts->max_y = get_unaligned_le16(&buf[10]);
166
167         return 0;
168 }
169
170 static int zet6223_probe(struct i2c_client *client,
171                          const struct i2c_device_id *id)
172 {
173         struct device *dev = &client->dev;
174         struct zet6223_ts *ts;
175         struct input_dev *input;
176         int error;
177
178         if (!client->irq) {
179                 dev_err(dev, "no irq specified\n");
180                 return -EINVAL;
181         }
182
183         ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
184         if (!ts)
185                 return -ENOMEM;
186
187         ts->client = client;
188
189         error = zet6223_power_on(ts);
190         if (error)
191                 return error;
192
193         error = zet6223_query_device(ts);
194         if (error)
195                 return error;
196
197         ts->input = input = devm_input_allocate_device(dev);
198         if (!input)
199                 return -ENOMEM;
200
201         input_set_drvdata(input, ts);
202
203         input->name = client->name;
204         input->id.bustype = BUS_I2C;
205         input->open = zet6223_start;
206         input->close = zet6223_stop;
207
208         input_set_abs_params(input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0);
209         input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0);
210
211         touchscreen_parse_properties(input, true, &ts->prop);
212
213         error = input_mt_init_slots(input, ts->fingernum,
214                                     INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
215         if (error)
216                 return error;
217
218         error = devm_request_threaded_irq(dev, client->irq, NULL, zet6223_irq,
219                                           IRQF_ONESHOT, client->name, ts);
220         if (error) {
221                 dev_err(dev, "failed to request irq %d: %d\n",
222                         client->irq, error);
223                 return error;
224         }
225
226         zet6223_stop(input);
227
228         error = input_register_device(input);
229         if (error)
230                 return error;
231
232         return 0;
233 }
234
235 static const struct of_device_id zet6223_of_match[] = {
236         { .compatible = "zeitec,zet6223" },
237         { }
238 };
239 MODULE_DEVICE_TABLE(of, zet6223_of_match);
240
241 static const struct i2c_device_id zet6223_id[] = {
242         { "zet6223", 0},
243         { }
244 };
245 MODULE_DEVICE_TABLE(i2c, zet6223_id);
246
247 static struct i2c_driver zet6223_driver = {
248         .driver = {
249                 .name = "zet6223",
250                 .of_match_table = zet6223_of_match,
251         },
252         .probe = zet6223_probe,
253         .id_table = zet6223_id
254 };
255 module_i2c_driver(zet6223_driver);
256
257 MODULE_AUTHOR("Jelle van der Waa <jelle@vdwaa.nl>");
258 MODULE_DESCRIPTION("ZEITEC zet622x I2C touchscreen driver");
259 MODULE_LICENSE("GPL");