1 /*
2  * Driver for cypress touch screen controller
3  *
4  * Copyright (c) 2009 Aava Mobile
5  *
6  * Some cleanups by Alan Cox <alan@linux.intel.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/input.h>
25 #include <linux/slab.h>
26 #include <linux/interrupt.h>
27 #include <linux/io.h>
28 #include <linux/i2c.h>
29 #include <linux/gpio.h>
30 #include <linux/input/cy8ctmg110_pdata.h>
31 
32 #define CY8CTMG110_DRIVER_NAME      "cy8ctmg110"
33 
34 /* Touch coordinates */
35 #define CY8CTMG110_X_MIN		0
36 #define CY8CTMG110_Y_MIN		0
37 #define CY8CTMG110_X_MAX		759
38 #define CY8CTMG110_Y_MAX		465
39 
40 
41 /* cy8ctmg110 register definitions */
42 #define CY8CTMG110_TOUCH_WAKEUP_TIME	0
43 #define CY8CTMG110_TOUCH_SLEEP_TIME	2
44 #define CY8CTMG110_TOUCH_X1		3
45 #define CY8CTMG110_TOUCH_Y1		5
46 #define CY8CTMG110_TOUCH_X2		7
47 #define CY8CTMG110_TOUCH_Y2		9
48 #define CY8CTMG110_FINGERS		11
49 #define CY8CTMG110_GESTURE		12
50 #define CY8CTMG110_REG_MAX		13
51 
52 
53 /*
54  * The touch driver structure.
55  */
56 struct cy8ctmg110 {
57 	struct input_dev *input;
58 	char phys[32];
59 	struct i2c_client *client;
60 	int reset_pin;
61 	int irq_pin;
62 };
63 
64 /*
65  * cy8ctmg110_power is the routine that is called when touch hardware
66  * will powered off or on.
67  */
68 static void cy8ctmg110_power(struct cy8ctmg110 *ts, bool poweron)
69 {
70 	if (ts->reset_pin)
71 		gpio_direction_output(ts->reset_pin, 1 - poweron);
72 }
73 
74 static int cy8ctmg110_write_regs(struct cy8ctmg110 *tsc, unsigned char reg,
75 		unsigned char len, unsigned char *value)
76 {
77 	struct i2c_client *client = tsc->client;
78 	int ret;
79 	unsigned char i2c_data[6];
80 
81 	BUG_ON(len > 5);
82 
83 	i2c_data[0] = reg;
84 	memcpy(i2c_data + 1, value, len);
85 
86 	ret = i2c_master_send(client, i2c_data, len + 1);
87 	if (ret != len + 1) {
88 		dev_err(&client->dev, "i2c write data cmd failed\n");
89 		return ret < 0 ? ret : -EIO;
90 	}
91 
92 	return 0;
93 }
94 
95 static int cy8ctmg110_read_regs(struct cy8ctmg110 *tsc,
96 		unsigned char *data, unsigned char len, unsigned char cmd)
97 {
98 	struct i2c_client *client = tsc->client;
99 	int ret;
100 	struct i2c_msg msg[2] = {
101 		/* first write slave position to i2c devices */
102 		{ client->addr, 0, 1, &cmd },
103 		/* Second read data from position */
104 		{ client->addr, I2C_M_RD, len, data }
105 	};
106 
107 	ret = i2c_transfer(client->adapter, msg, 2);
108 	if (ret < 0)
109 		return ret;
110 
111 	return 0;
112 }
113 
114 static int cy8ctmg110_touch_pos(struct cy8ctmg110 *tsc)
115 {
116 	struct input_dev *input = tsc->input;
117 	unsigned char reg_p[CY8CTMG110_REG_MAX];
118 	int x, y;
119 
120 	memset(reg_p, 0, CY8CTMG110_REG_MAX);
121 
122 	/* Reading coordinates */
123 	if (cy8ctmg110_read_regs(tsc, reg_p, 9, CY8CTMG110_TOUCH_X1) != 0)
124 		return -EIO;
125 
126 	y = reg_p[2] << 8 | reg_p[3];
127 	x = reg_p[0] << 8 | reg_p[1];
128 
129 	/* Number of touch */
130 	if (reg_p[8] == 0) {
131 		input_report_key(input, BTN_TOUCH, 0);
132 	} else  {
133 		input_report_key(input, BTN_TOUCH, 1);
134 		input_report_abs(input, ABS_X, x);
135 		input_report_abs(input, ABS_Y, y);
136 	}
137 
138 	input_sync(input);
139 
140 	return 0;
141 }
142 
143 static int cy8ctmg110_set_sleepmode(struct cy8ctmg110 *ts, bool sleep)
144 {
145 	unsigned char reg_p[3];
146 
147 	if (sleep) {
148 		reg_p[0] = 0x00;
149 		reg_p[1] = 0xff;
150 		reg_p[2] = 5;
151 	} else {
152 		reg_p[0] = 0x10;
153 		reg_p[1] = 0xff;
154 		reg_p[2] = 0;
155 	}
156 
157 	return cy8ctmg110_write_regs(ts, CY8CTMG110_TOUCH_WAKEUP_TIME, 3, reg_p);
158 }
159 
160 static irqreturn_t cy8ctmg110_irq_thread(int irq, void *dev_id)
161 {
162 	struct cy8ctmg110 *tsc = dev_id;
163 
164 	cy8ctmg110_touch_pos(tsc);
165 
166 	return IRQ_HANDLED;
167 }
168 
169 static int __devinit cy8ctmg110_probe(struct i2c_client *client,
170 					const struct i2c_device_id *id)
171 {
172 	const struct cy8ctmg110_pdata *pdata = client->dev.platform_data;
173 	struct cy8ctmg110 *ts;
174 	struct input_dev *input_dev;
175 	int err;
176 
177 	/* No pdata no way forward */
178 	if (pdata == NULL) {
179 		dev_err(&client->dev, "no pdata\n");
180 		return -ENODEV;
181 	}
182 
183 	if (!i2c_check_functionality(client->adapter,
184 					I2C_FUNC_SMBUS_READ_WORD_DATA))
185 		return -EIO;
186 
187 	ts = kzalloc(sizeof(struct cy8ctmg110), GFP_KERNEL);
188 	input_dev = input_allocate_device();
189 	if (!ts || !input_dev) {
190 		err = -ENOMEM;
191 		goto err_free_mem;
192 	}
193 
194 	ts->client = client;
195 	ts->input = input_dev;
196 	ts->reset_pin = pdata->reset_pin;
197 	ts->irq_pin = pdata->irq_pin;
198 
199 	snprintf(ts->phys, sizeof(ts->phys),
200 		 "%s/input0", dev_name(&client->dev));
201 
202 	input_dev->name = CY8CTMG110_DRIVER_NAME " Touchscreen";
203 	input_dev->phys = ts->phys;
204 	input_dev->id.bustype = BUS_I2C;
205 	input_dev->dev.parent = &client->dev;
206 
207 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
208 	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
209 
210 	input_set_abs_params(input_dev, ABS_X,
211 			CY8CTMG110_X_MIN, CY8CTMG110_X_MAX, 4, 0);
212 	input_set_abs_params(input_dev, ABS_Y,
213 			CY8CTMG110_Y_MIN, CY8CTMG110_Y_MAX, 4, 0);
214 
215 	if (ts->reset_pin) {
216 		err = gpio_request(ts->reset_pin, NULL);
217 		if (err) {
218 			dev_err(&client->dev,
219 				"Unable to request GPIO pin %d.\n",
220 				ts->reset_pin);
221 			goto err_free_mem;
222 		}
223 	}
224 
225 	cy8ctmg110_power(ts, true);
226 	cy8ctmg110_set_sleepmode(ts, false);
227 
228 	err = gpio_request(ts->irq_pin, "touch_irq_key");
229 	if (err < 0) {
230 		dev_err(&client->dev,
231 			"Failed to request GPIO %d, error %d\n",
232 			ts->irq_pin, err);
233 		goto err_shutoff_device;
234 	}
235 
236 	err = gpio_direction_input(ts->irq_pin);
237 	if (err < 0) {
238 		dev_err(&client->dev,
239 			"Failed to configure input direction for GPIO %d, error %d\n",
240 			ts->irq_pin, err);
241 		goto err_free_irq_gpio;
242 	}
243 
244 	client->irq = gpio_to_irq(ts->irq_pin);
245 	if (client->irq < 0) {
246 		err = client->irq;
247 		dev_err(&client->dev,
248 			"Unable to get irq number for GPIO %d, error %d\n",
249 			ts->irq_pin, err);
250 		goto err_free_irq_gpio;
251 	}
252 
253 	err = request_threaded_irq(client->irq, NULL, cy8ctmg110_irq_thread,
254 				   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
255 				   "touch_reset_key", ts);
256 	if (err < 0) {
257 		dev_err(&client->dev,
258 			"irq %d busy? error %d\n", client->irq, err);
259 		goto err_free_irq_gpio;
260 	}
261 
262 	err = input_register_device(input_dev);
263 	if (err)
264 		goto err_free_irq;
265 
266 	i2c_set_clientdata(client, ts);
267 	device_init_wakeup(&client->dev, 1);
268 	return 0;
269 
270 err_free_irq:
271 	free_irq(client->irq, ts);
272 err_free_irq_gpio:
273 	gpio_free(ts->irq_pin);
274 err_shutoff_device:
275 	cy8ctmg110_set_sleepmode(ts, true);
276 	cy8ctmg110_power(ts, false);
277 	if (ts->reset_pin)
278 		gpio_free(ts->reset_pin);
279 err_free_mem:
280 	input_free_device(input_dev);
281 	kfree(ts);
282 	return err;
283 }
284 
285 #ifdef CONFIG_PM
286 static int cy8ctmg110_suspend(struct device *dev)
287 {
288 	struct i2c_client *client = to_i2c_client(dev);
289 	struct cy8ctmg110 *ts = i2c_get_clientdata(client);
290 
291 	if (device_may_wakeup(&client->dev))
292 		enable_irq_wake(client->irq);
293 	else {
294 		cy8ctmg110_set_sleepmode(ts, true);
295 		cy8ctmg110_power(ts, false);
296 	}
297 	return 0;
298 }
299 
300 static int cy8ctmg110_resume(struct device *dev)
301 {
302 	struct i2c_client *client = to_i2c_client(dev);
303 	struct cy8ctmg110 *ts = i2c_get_clientdata(client);
304 
305 	if (device_may_wakeup(&client->dev))
306 		disable_irq_wake(client->irq);
307 	else {
308 		cy8ctmg110_power(ts, true);
309 		cy8ctmg110_set_sleepmode(ts, false);
310 	}
311 	return 0;
312 }
313 
314 static SIMPLE_DEV_PM_OPS(cy8ctmg110_pm, cy8ctmg110_suspend, cy8ctmg110_resume);
315 #endif
316 
317 static int __devexit cy8ctmg110_remove(struct i2c_client *client)
318 {
319 	struct cy8ctmg110 *ts = i2c_get_clientdata(client);
320 
321 	cy8ctmg110_set_sleepmode(ts, true);
322 	cy8ctmg110_power(ts, false);
323 
324 	free_irq(client->irq, ts);
325 	input_unregister_device(ts->input);
326 	gpio_free(ts->irq_pin);
327 	if (ts->reset_pin)
328 		gpio_free(ts->reset_pin);
329 	kfree(ts);
330 
331 	return 0;
332 }
333 
334 static const struct i2c_device_id cy8ctmg110_idtable[] = {
335 	{ CY8CTMG110_DRIVER_NAME, 1 },
336 	{ }
337 };
338 
339 MODULE_DEVICE_TABLE(i2c, cy8ctmg110_idtable);
340 
341 static struct i2c_driver cy8ctmg110_driver = {
342 	.driver		= {
343 		.owner	= THIS_MODULE,
344 		.name	= CY8CTMG110_DRIVER_NAME,
345 #ifdef CONFIG_PM
346 		.pm	= &cy8ctmg110_pm,
347 #endif
348 	},
349 	.id_table	= cy8ctmg110_idtable,
350 	.probe		= cy8ctmg110_probe,
351 	.remove		= __devexit_p(cy8ctmg110_remove),
352 };
353 
354 module_i2c_driver(cy8ctmg110_driver);
355 
356 MODULE_AUTHOR("Samuli Konttila <samuli.konttila@aavamobile.com>");
357 MODULE_DESCRIPTION("cy8ctmg110 TouchScreen Driver");
358 MODULE_LICENSE("GPL v2");
359