1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * Touch Screen driver for Renesas MIGO-R Platform |
4 | * |
5 | * Copyright (c) 2008 Magnus Damm |
6 | * Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>, |
7 | * Kenati Technologies Pvt Ltd. |
8 | */ |
9 | #include <linux/module.h> |
10 | #include <linux/kernel.h> |
11 | #include <linux/input.h> |
12 | #include <linux/interrupt.h> |
13 | #include <linux/pm.h> |
14 | #include <linux/slab.h> |
15 | #include <asm/io.h> |
16 | #include <linux/i2c.h> |
17 | #include <linux/timer.h> |
18 | |
19 | #define EVENT_PENDOWN 1 |
20 | #define EVENT_REPEAT 2 |
21 | #define EVENT_PENUP 3 |
22 | |
23 | struct migor_ts_priv { |
24 | struct i2c_client *client; |
25 | struct input_dev *input; |
26 | int irq; |
27 | }; |
28 | |
29 | static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11, |
30 | 0x01, 0x06, 0x07, }; |
31 | static const u_int8_t migor_ts_dis_seq[17] = { }; |
32 | |
33 | static irqreturn_t migor_ts_isr(int irq, void *dev_id) |
34 | { |
35 | struct migor_ts_priv *priv = dev_id; |
36 | unsigned short xpos, ypos; |
37 | unsigned char event; |
38 | u_int8_t buf[16]; |
39 | |
40 | /* |
41 | * The touch screen controller chip is hooked up to the CPU |
42 | * using I2C and a single interrupt line. The interrupt line |
43 | * is pulled low whenever someone taps the screen. To deassert |
44 | * the interrupt line we need to acknowledge the interrupt by |
45 | * communicating with the controller over the slow i2c bus. |
46 | * |
47 | * Since I2C bus controller may sleep we are using threaded |
48 | * IRQ here. |
49 | */ |
50 | |
51 | memset(buf, 0, sizeof(buf)); |
52 | |
53 | /* Set Index 0 */ |
54 | buf[0] = 0; |
55 | if (i2c_master_send(client: priv->client, buf, count: 1) != 1) { |
56 | dev_err(&priv->client->dev, "Unable to write i2c index\n" ); |
57 | goto out; |
58 | } |
59 | |
60 | /* Now do Page Read */ |
61 | if (i2c_master_recv(client: priv->client, buf, count: sizeof(buf)) != sizeof(buf)) { |
62 | dev_err(&priv->client->dev, "Unable to read i2c page\n" ); |
63 | goto out; |
64 | } |
65 | |
66 | ypos = ((buf[9] & 0x03) << 8 | buf[8]); |
67 | xpos = ((buf[11] & 0x03) << 8 | buf[10]); |
68 | event = buf[12]; |
69 | |
70 | switch (event) { |
71 | case EVENT_PENDOWN: |
72 | case EVENT_REPEAT: |
73 | input_report_key(dev: priv->input, BTN_TOUCH, value: 1); |
74 | input_report_abs(dev: priv->input, ABS_X, value: ypos); /*X-Y swap*/ |
75 | input_report_abs(dev: priv->input, ABS_Y, value: xpos); |
76 | input_sync(dev: priv->input); |
77 | break; |
78 | |
79 | case EVENT_PENUP: |
80 | input_report_key(dev: priv->input, BTN_TOUCH, value: 0); |
81 | input_sync(dev: priv->input); |
82 | break; |
83 | } |
84 | |
85 | out: |
86 | return IRQ_HANDLED; |
87 | } |
88 | |
89 | static int migor_ts_open(struct input_dev *dev) |
90 | { |
91 | struct migor_ts_priv *priv = input_get_drvdata(dev); |
92 | struct i2c_client *client = priv->client; |
93 | int count; |
94 | |
95 | /* enable controller */ |
96 | count = i2c_master_send(client, buf: migor_ts_ena_seq, |
97 | count: sizeof(migor_ts_ena_seq)); |
98 | if (count != sizeof(migor_ts_ena_seq)) { |
99 | dev_err(&client->dev, "Unable to enable touchscreen.\n" ); |
100 | return -ENXIO; |
101 | } |
102 | |
103 | return 0; |
104 | } |
105 | |
106 | static void migor_ts_close(struct input_dev *dev) |
107 | { |
108 | struct migor_ts_priv *priv = input_get_drvdata(dev); |
109 | struct i2c_client *client = priv->client; |
110 | |
111 | disable_irq(irq: priv->irq); |
112 | |
113 | /* disable controller */ |
114 | i2c_master_send(client, buf: migor_ts_dis_seq, count: sizeof(migor_ts_dis_seq)); |
115 | |
116 | enable_irq(irq: priv->irq); |
117 | } |
118 | |
119 | static int migor_ts_probe(struct i2c_client *client) |
120 | { |
121 | struct migor_ts_priv *priv; |
122 | struct input_dev *input; |
123 | int error; |
124 | |
125 | priv = kzalloc(size: sizeof(*priv), GFP_KERNEL); |
126 | input = input_allocate_device(); |
127 | if (!priv || !input) { |
128 | dev_err(&client->dev, "failed to allocate memory\n" ); |
129 | error = -ENOMEM; |
130 | goto err_free_mem; |
131 | } |
132 | |
133 | priv->client = client; |
134 | priv->input = input; |
135 | priv->irq = client->irq; |
136 | |
137 | input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
138 | |
139 | __set_bit(BTN_TOUCH, input->keybit); |
140 | |
141 | input_set_abs_params(dev: input, ABS_X, min: 95, max: 955, fuzz: 0, flat: 0); |
142 | input_set_abs_params(dev: input, ABS_Y, min: 85, max: 935, fuzz: 0, flat: 0); |
143 | |
144 | input->name = client->name; |
145 | input->id.bustype = BUS_I2C; |
146 | input->dev.parent = &client->dev; |
147 | |
148 | input->open = migor_ts_open; |
149 | input->close = migor_ts_close; |
150 | |
151 | input_set_drvdata(dev: input, data: priv); |
152 | |
153 | error = request_threaded_irq(irq: priv->irq, NULL, thread_fn: migor_ts_isr, |
154 | IRQF_TRIGGER_LOW | IRQF_ONESHOT, |
155 | name: client->name, dev: priv); |
156 | if (error) { |
157 | dev_err(&client->dev, "Unable to request touchscreen IRQ.\n" ); |
158 | goto err_free_mem; |
159 | } |
160 | |
161 | error = input_register_device(input); |
162 | if (error) |
163 | goto err_free_irq; |
164 | |
165 | i2c_set_clientdata(client, data: priv); |
166 | device_init_wakeup(dev: &client->dev, enable: 1); |
167 | |
168 | return 0; |
169 | |
170 | err_free_irq: |
171 | free_irq(priv->irq, priv); |
172 | err_free_mem: |
173 | input_free_device(dev: input); |
174 | kfree(objp: priv); |
175 | return error; |
176 | } |
177 | |
178 | static void migor_ts_remove(struct i2c_client *client) |
179 | { |
180 | struct migor_ts_priv *priv = i2c_get_clientdata(client); |
181 | |
182 | free_irq(priv->irq, priv); |
183 | input_unregister_device(priv->input); |
184 | kfree(objp: priv); |
185 | |
186 | dev_set_drvdata(dev: &client->dev, NULL); |
187 | } |
188 | |
189 | static int migor_ts_suspend(struct device *dev) |
190 | { |
191 | struct i2c_client *client = to_i2c_client(dev); |
192 | struct migor_ts_priv *priv = i2c_get_clientdata(client); |
193 | |
194 | if (device_may_wakeup(dev: &client->dev)) |
195 | enable_irq_wake(irq: priv->irq); |
196 | |
197 | return 0; |
198 | } |
199 | |
200 | static int migor_ts_resume(struct device *dev) |
201 | { |
202 | struct i2c_client *client = to_i2c_client(dev); |
203 | struct migor_ts_priv *priv = i2c_get_clientdata(client); |
204 | |
205 | if (device_may_wakeup(dev: &client->dev)) |
206 | disable_irq_wake(irq: priv->irq); |
207 | |
208 | return 0; |
209 | } |
210 | |
211 | static DEFINE_SIMPLE_DEV_PM_OPS(migor_ts_pm, migor_ts_suspend, migor_ts_resume); |
212 | |
213 | static const struct i2c_device_id migor_ts_id[] = { |
214 | { "migor_ts" , 0 }, |
215 | { } |
216 | }; |
217 | MODULE_DEVICE_TABLE(i2c, migor_ts_id); |
218 | |
219 | static struct i2c_driver migor_ts_driver = { |
220 | .driver = { |
221 | .name = "migor_ts" , |
222 | .pm = pm_sleep_ptr(&migor_ts_pm), |
223 | }, |
224 | .probe = migor_ts_probe, |
225 | .remove = migor_ts_remove, |
226 | .id_table = migor_ts_id, |
227 | }; |
228 | |
229 | module_i2c_driver(migor_ts_driver); |
230 | |
231 | MODULE_DESCRIPTION("MigoR Touchscreen driver" ); |
232 | MODULE_AUTHOR("Magnus Damm <damm@opensource.se>" ); |
233 | MODULE_LICENSE("GPL" ); |
234 | |