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
migor_ts_isr(int irq,void * dev_id)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(priv->client, buf, 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(priv->client, buf, 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(priv->input, BTN_TOUCH, 1);
74 input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/
75 input_report_abs(priv->input, ABS_Y, xpos);
76 input_sync(priv->input);
77 break;
78
79 case EVENT_PENUP:
80 input_report_key(priv->input, BTN_TOUCH, 0);
81 input_sync(priv->input);
82 break;
83 }
84
85 out:
86 return IRQ_HANDLED;
87 }
88
migor_ts_open(struct input_dev * dev)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, migor_ts_ena_seq,
97 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
migor_ts_close(struct input_dev * dev)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(priv->irq);
112
113 /* disable controller */
114 i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq));
115
116 enable_irq(priv->irq);
117 }
118
migor_ts_probe(struct i2c_client * client)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(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(input, ABS_X, 95, 955, 0, 0);
142 input_set_abs_params(input, ABS_Y, 85, 935, 0, 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(input, priv);
152
153 error = request_threaded_irq(priv->irq, NULL, migor_ts_isr,
154 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
155 client->name, 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, priv);
166 device_init_wakeup(&client->dev, 1);
167
168 return 0;
169
170 err_free_irq:
171 free_irq(priv->irq, priv);
172 err_free_mem:
173 input_free_device(input);
174 kfree(priv);
175 return error;
176 }
177
migor_ts_remove(struct i2c_client * client)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(priv);
185
186 dev_set_drvdata(&client->dev, NULL);
187 }
188
migor_ts_suspend(struct device * dev)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(&client->dev))
195 enable_irq_wake(priv->irq);
196
197 return 0;
198 }
199
migor_ts_resume(struct device * dev)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(&client->dev))
206 disable_irq_wake(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" },
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