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(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(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(client: ts->client, buf, count: 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(p: buf + 1); |
80 | for (i = 0; i < ts->fingernum; i++) { |
81 | if (!(finger_bits & BIT(15 - i))) |
82 | continue; |
83 | |
84 | input_mt_slot(dev: ts->input, slot: i); |
85 | input_mt_report_slot_state(dev: ts->input, MT_TOOL_FINGER, active: true); |
86 | input_event(dev: ts->input, EV_ABS, ABS_MT_POSITION_X, |
87 | value: ((buf[i + 3] >> 4) << 8) + buf[i + 4]); |
88 | input_event(dev: ts->input, EV_ABS, ABS_MT_POSITION_Y, |
89 | value: ((buf[i + 3] & 0xF) << 8) + buf[i + 5]); |
90 | } |
91 | |
92 | input_mt_sync_frame(dev: ts->input); |
93 | input_sync(dev: 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), consumers: 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 | consumers: ts->supplies); |
115 | if (error) |
116 | return error; |
117 | |
118 | error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies), consumers: 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(client: ts->client, buf: &cmd, count: 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(client: ts->client, buf, count: 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(p: &buf[8]); |
165 | ts->max_y = get_unaligned_le16(p: &buf[10]); |
166 | |
167 | return 0; |
168 | } |
169 | |
170 | static int zet6223_probe(struct i2c_client *client) |
171 | { |
172 | struct device *dev = &client->dev; |
173 | struct zet6223_ts *ts; |
174 | struct input_dev *input; |
175 | int error; |
176 | |
177 | if (!client->irq) { |
178 | dev_err(dev, "no irq specified\n" ); |
179 | return -EINVAL; |
180 | } |
181 | |
182 | ts = devm_kzalloc(dev, size: sizeof(*ts), GFP_KERNEL); |
183 | if (!ts) |
184 | return -ENOMEM; |
185 | |
186 | ts->client = client; |
187 | |
188 | error = zet6223_power_on(ts); |
189 | if (error) |
190 | return error; |
191 | |
192 | error = zet6223_query_device(ts); |
193 | if (error) |
194 | return error; |
195 | |
196 | ts->input = input = devm_input_allocate_device(dev); |
197 | if (!input) |
198 | return -ENOMEM; |
199 | |
200 | input_set_drvdata(dev: input, data: ts); |
201 | |
202 | input->name = client->name; |
203 | input->id.bustype = BUS_I2C; |
204 | input->open = zet6223_start; |
205 | input->close = zet6223_stop; |
206 | |
207 | input_set_abs_params(dev: input, ABS_MT_POSITION_X, min: 0, max: ts->max_x, fuzz: 0, flat: 0); |
208 | input_set_abs_params(dev: input, ABS_MT_POSITION_Y, min: 0, max: ts->max_y, fuzz: 0, flat: 0); |
209 | |
210 | touchscreen_parse_properties(input, multitouch: true, prop: &ts->prop); |
211 | |
212 | error = input_mt_init_slots(dev: input, num_slots: ts->fingernum, |
213 | INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); |
214 | if (error) |
215 | return error; |
216 | |
217 | error = devm_request_threaded_irq(dev, irq: client->irq, NULL, thread_fn: zet6223_irq, |
218 | IRQF_ONESHOT, devname: client->name, dev_id: ts); |
219 | if (error) { |
220 | dev_err(dev, "failed to request irq %d: %d\n" , |
221 | client->irq, error); |
222 | return error; |
223 | } |
224 | |
225 | zet6223_stop(dev: input); |
226 | |
227 | error = input_register_device(input); |
228 | if (error) |
229 | return error; |
230 | |
231 | return 0; |
232 | } |
233 | |
234 | static const struct of_device_id zet6223_of_match[] = { |
235 | { .compatible = "zeitec,zet6223" }, |
236 | { } |
237 | }; |
238 | MODULE_DEVICE_TABLE(of, zet6223_of_match); |
239 | |
240 | static const struct i2c_device_id zet6223_id[] = { |
241 | { "zet6223" , 0}, |
242 | { } |
243 | }; |
244 | MODULE_DEVICE_TABLE(i2c, zet6223_id); |
245 | |
246 | static struct i2c_driver zet6223_driver = { |
247 | .driver = { |
248 | .name = "zet6223" , |
249 | .of_match_table = zet6223_of_match, |
250 | }, |
251 | .probe = zet6223_probe, |
252 | .id_table = zet6223_id |
253 | }; |
254 | module_i2c_driver(zet6223_driver); |
255 | |
256 | MODULE_AUTHOR("Jelle van der Waa <jelle@vdwaa.nl>" ); |
257 | MODULE_DESCRIPTION("ZEITEC zet622x I2C touchscreen driver" ); |
258 | MODULE_LICENSE("GPL" ); |
259 | |