1 /*
2  * Driver for Pixcir I2C touchscreen controllers.
3  *
4  * Copyright (C) 2010-2011 Pixcir, Inc.
5  *
6  * This software is licensed under the terms of the GNU General Public
7  * License version 2, as published by the Free Software Foundation, and
8  * may be copied, distributed, and modified under those terms.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public
16  * License along with this library; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
18  */
19 
20 #include <linux/delay.h>
21 #include <linux/module.h>
22 #include <linux/interrupt.h>
23 #include <linux/slab.h>
24 #include <linux/i2c.h>
25 #include <linux/input.h>
26 #include <linux/input/pixcir_ts.h>
27 
28 struct pixcir_i2c_ts_data {
29 	struct i2c_client *client;
30 	struct input_dev *input;
31 	const struct pixcir_ts_platform_data *chip;
32 	bool exiting;
33 };
34 
35 static void pixcir_ts_poscheck(struct pixcir_i2c_ts_data *data)
36 {
37 	struct pixcir_i2c_ts_data *tsdata = data;
38 	u8 rdbuf[10], wrbuf[1] = { 0 };
39 	u8 touch;
40 	int ret;
41 
42 	ret = i2c_master_send(tsdata->client, wrbuf, sizeof(wrbuf));
43 	if (ret != sizeof(wrbuf)) {
44 		dev_err(&tsdata->client->dev,
45 			"%s: i2c_master_send failed(), ret=%d\n",
46 			__func__, ret);
47 		return;
48 	}
49 
50 	ret = i2c_master_recv(tsdata->client, rdbuf, sizeof(rdbuf));
51 	if (ret != sizeof(rdbuf)) {
52 		dev_err(&tsdata->client->dev,
53 			"%s: i2c_master_recv failed(), ret=%d\n",
54 			__func__, ret);
55 		return;
56 	}
57 
58 	touch = rdbuf[0];
59 	if (touch) {
60 		u16 posx1 = (rdbuf[3] << 8) | rdbuf[2];
61 		u16 posy1 = (rdbuf[5] << 8) | rdbuf[4];
62 		u16 posx2 = (rdbuf[7] << 8) | rdbuf[6];
63 		u16 posy2 = (rdbuf[9] << 8) | rdbuf[8];
64 
65 		input_report_key(tsdata->input, BTN_TOUCH, 1);
66 		input_report_abs(tsdata->input, ABS_X, posx1);
67 		input_report_abs(tsdata->input, ABS_Y, posy1);
68 
69 		input_report_abs(tsdata->input, ABS_MT_POSITION_X, posx1);
70 		input_report_abs(tsdata->input, ABS_MT_POSITION_Y, posy1);
71 		input_mt_sync(tsdata->input);
72 
73 		if (touch == 2) {
74 			input_report_abs(tsdata->input,
75 					 ABS_MT_POSITION_X, posx2);
76 			input_report_abs(tsdata->input,
77 					 ABS_MT_POSITION_Y, posy2);
78 			input_mt_sync(tsdata->input);
79 		}
80 	} else {
81 		input_report_key(tsdata->input, BTN_TOUCH, 0);
82 	}
83 
84 	input_sync(tsdata->input);
85 }
86 
87 static irqreturn_t pixcir_ts_isr(int irq, void *dev_id)
88 {
89 	struct pixcir_i2c_ts_data *tsdata = dev_id;
90 
91 	while (!tsdata->exiting) {
92 		pixcir_ts_poscheck(tsdata);
93 
94 		if (tsdata->chip->attb_read_val())
95 			break;
96 
97 		msleep(20);
98 	}
99 
100 	return IRQ_HANDLED;
101 }
102 
103 #ifdef CONFIG_PM_SLEEP
104 static int pixcir_i2c_ts_suspend(struct device *dev)
105 {
106 	struct i2c_client *client = to_i2c_client(dev);
107 
108 	if (device_may_wakeup(&client->dev))
109 		enable_irq_wake(client->irq);
110 
111 	return 0;
112 }
113 
114 static int pixcir_i2c_ts_resume(struct device *dev)
115 {
116 	struct i2c_client *client = to_i2c_client(dev);
117 
118 	if (device_may_wakeup(&client->dev))
119 		disable_irq_wake(client->irq);
120 
121 	return 0;
122 }
123 #endif
124 
125 static SIMPLE_DEV_PM_OPS(pixcir_dev_pm_ops,
126 			 pixcir_i2c_ts_suspend, pixcir_i2c_ts_resume);
127 
128 static int pixcir_i2c_ts_probe(struct i2c_client *client,
129 					 const struct i2c_device_id *id)
130 {
131 	const struct pixcir_ts_platform_data *pdata =
132 			dev_get_platdata(&client->dev);
133 	struct pixcir_i2c_ts_data *tsdata;
134 	struct input_dev *input;
135 	int error;
136 
137 	if (!pdata) {
138 		dev_err(&client->dev, "platform data not defined\n");
139 		return -EINVAL;
140 	}
141 
142 	tsdata = kzalloc(sizeof(*tsdata), GFP_KERNEL);
143 	input = input_allocate_device();
144 	if (!tsdata || !input) {
145 		dev_err(&client->dev, "Failed to allocate driver data!\n");
146 		error = -ENOMEM;
147 		goto err_free_mem;
148 	}
149 
150 	tsdata->client = client;
151 	tsdata->input = input;
152 	tsdata->chip = pdata;
153 
154 	input->name = client->name;
155 	input->id.bustype = BUS_I2C;
156 	input->dev.parent = &client->dev;
157 
158 	__set_bit(EV_KEY, input->evbit);
159 	__set_bit(EV_ABS, input->evbit);
160 	__set_bit(BTN_TOUCH, input->keybit);
161 	input_set_abs_params(input, ABS_X, 0, pdata->x_max, 0, 0);
162 	input_set_abs_params(input, ABS_Y, 0, pdata->y_max, 0, 0);
163 	input_set_abs_params(input, ABS_MT_POSITION_X, 0, pdata->x_max, 0, 0);
164 	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, pdata->y_max, 0, 0);
165 
166 	input_set_drvdata(input, tsdata);
167 
168 	error = request_threaded_irq(client->irq, NULL, pixcir_ts_isr,
169 				     IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
170 				     client->name, tsdata);
171 	if (error) {
172 		dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
173 		goto err_free_mem;
174 	}
175 
176 	error = input_register_device(input);
177 	if (error)
178 		goto err_free_irq;
179 
180 	i2c_set_clientdata(client, tsdata);
181 	device_init_wakeup(&client->dev, 1);
182 
183 	return 0;
184 
185 err_free_irq:
186 	free_irq(client->irq, tsdata);
187 err_free_mem:
188 	input_free_device(input);
189 	kfree(tsdata);
190 	return error;
191 }
192 
193 static int pixcir_i2c_ts_remove(struct i2c_client *client)
194 {
195 	struct pixcir_i2c_ts_data *tsdata = i2c_get_clientdata(client);
196 
197 	device_init_wakeup(&client->dev, 0);
198 
199 	tsdata->exiting = true;
200 	mb();
201 	free_irq(client->irq, tsdata);
202 
203 	input_unregister_device(tsdata->input);
204 	kfree(tsdata);
205 
206 	return 0;
207 }
208 
209 static const struct i2c_device_id pixcir_i2c_ts_id[] = {
210 	{ "pixcir_ts", 0 },
211 	{ }
212 };
213 MODULE_DEVICE_TABLE(i2c, pixcir_i2c_ts_id);
214 
215 static struct i2c_driver pixcir_i2c_ts_driver = {
216 	.driver = {
217 		.owner	= THIS_MODULE,
218 		.name	= "pixcir_ts",
219 		.pm	= &pixcir_dev_pm_ops,
220 	},
221 	.probe		= pixcir_i2c_ts_probe,
222 	.remove		= pixcir_i2c_ts_remove,
223 	.id_table	= pixcir_i2c_ts_id,
224 };
225 
226 module_i2c_driver(pixcir_i2c_ts_driver);
227 
228 MODULE_AUTHOR("Jianchun Bian <jcbian@pixcir.com.cn>, Dequan Meng <dqmeng@pixcir.com.cn>");
229 MODULE_DESCRIPTION("Pixcir I2C Touchscreen Driver");
230 MODULE_LICENSE("GPL");
231