1 /* 2 * ST1232 Touchscreen Controller Driver 3 * 4 * Copyright (C) 2010 Renesas Solutions Corp. 5 * Tony SIM <chinyeow.sim.xt@renesas.com> 6 * 7 * Using code from: 8 * - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c 9 * Copyright (C) 2007 Google, Inc. 10 * 11 * This software is licensed under the terms of the GNU General Public 12 * License version 2, as published by the Free Software Foundation, and 13 * may be copied, distributed, and modified under those terms. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 */ 20 21 #include <linux/delay.h> 22 #include <linux/i2c.h> 23 #include <linux/input.h> 24 #include <linux/interrupt.h> 25 #include <linux/module.h> 26 #include <linux/slab.h> 27 #include <linux/types.h> 28 29 #define ST1232_TS_NAME "st1232-ts" 30 31 #define MIN_X 0x00 32 #define MIN_Y 0x00 33 #define MAX_X 0x31f /* (800 - 1) */ 34 #define MAX_Y 0x1df /* (480 - 1) */ 35 #define MAX_AREA 0xff 36 #define MAX_FINGERS 2 37 38 struct st1232_ts_finger { 39 u16 x; 40 u16 y; 41 u8 t; 42 bool is_valid; 43 }; 44 45 struct st1232_ts_data { 46 struct i2c_client *client; 47 struct input_dev *input_dev; 48 struct st1232_ts_finger finger[MAX_FINGERS]; 49 }; 50 51 static int st1232_ts_read_data(struct st1232_ts_data *ts) 52 { 53 struct st1232_ts_finger *finger = ts->finger; 54 struct i2c_client *client = ts->client; 55 struct i2c_msg msg[2]; 56 int error; 57 u8 start_reg; 58 u8 buf[10]; 59 60 /* read touchscreen data from ST1232 */ 61 msg[0].addr = client->addr; 62 msg[0].flags = 0; 63 msg[0].len = 1; 64 msg[0].buf = &start_reg; 65 start_reg = 0x10; 66 67 msg[1].addr = ts->client->addr; 68 msg[1].flags = I2C_M_RD; 69 msg[1].len = sizeof(buf); 70 msg[1].buf = buf; 71 72 error = i2c_transfer(client->adapter, msg, 2); 73 if (error < 0) 74 return error; 75 76 /* get "valid" bits */ 77 finger[0].is_valid = buf[2] >> 7; 78 finger[1].is_valid = buf[5] >> 7; 79 80 /* get xy coordinate */ 81 if (finger[0].is_valid) { 82 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3]; 83 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4]; 84 finger[0].t = buf[8]; 85 } 86 87 if (finger[1].is_valid) { 88 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6]; 89 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7]; 90 finger[1].t = buf[9]; 91 } 92 93 return 0; 94 } 95 96 static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id) 97 { 98 struct st1232_ts_data *ts = dev_id; 99 struct st1232_ts_finger *finger = ts->finger; 100 struct input_dev *input_dev = ts->input_dev; 101 int count = 0; 102 int i, ret; 103 104 ret = st1232_ts_read_data(ts); 105 if (ret < 0) 106 goto end; 107 108 /* multi touch protocol */ 109 for (i = 0; i < MAX_FINGERS; i++) { 110 if (!finger[i].is_valid) 111 continue; 112 113 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t); 114 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x); 115 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y); 116 input_mt_sync(input_dev); 117 count++; 118 } 119 120 /* SYN_MT_REPORT only if no contact */ 121 if (!count) 122 input_mt_sync(input_dev); 123 124 /* SYN_REPORT */ 125 input_sync(input_dev); 126 127 end: 128 return IRQ_HANDLED; 129 } 130 131 static int __devinit st1232_ts_probe(struct i2c_client *client, 132 const struct i2c_device_id *id) 133 { 134 struct st1232_ts_data *ts; 135 struct input_dev *input_dev; 136 int error; 137 138 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 139 dev_err(&client->dev, "need I2C_FUNC_I2C\n"); 140 return -EIO; 141 } 142 143 if (!client->irq) { 144 dev_err(&client->dev, "no IRQ?\n"); 145 return -EINVAL; 146 } 147 148 149 ts = kzalloc(sizeof(struct st1232_ts_data), GFP_KERNEL); 150 input_dev = input_allocate_device(); 151 if (!ts || !input_dev) { 152 error = -ENOMEM; 153 goto err_free_mem; 154 } 155 156 ts->client = client; 157 ts->input_dev = input_dev; 158 159 input_dev->name = "st1232-touchscreen"; 160 input_dev->id.bustype = BUS_I2C; 161 input_dev->dev.parent = &client->dev; 162 163 __set_bit(EV_SYN, input_dev->evbit); 164 __set_bit(EV_KEY, input_dev->evbit); 165 __set_bit(EV_ABS, input_dev->evbit); 166 167 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0); 168 input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0); 169 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0); 170 171 error = request_threaded_irq(client->irq, NULL, st1232_ts_irq_handler, 172 IRQF_ONESHOT, client->name, ts); 173 if (error) { 174 dev_err(&client->dev, "Failed to register interrupt\n"); 175 goto err_free_mem; 176 } 177 178 error = input_register_device(ts->input_dev); 179 if (error) { 180 dev_err(&client->dev, "Unable to register %s input device\n", 181 input_dev->name); 182 goto err_free_irq; 183 } 184 185 i2c_set_clientdata(client, ts); 186 device_init_wakeup(&client->dev, 1); 187 188 return 0; 189 190 err_free_irq: 191 free_irq(client->irq, ts); 192 err_free_mem: 193 input_free_device(input_dev); 194 kfree(ts); 195 return error; 196 } 197 198 static int __devexit st1232_ts_remove(struct i2c_client *client) 199 { 200 struct st1232_ts_data *ts = i2c_get_clientdata(client); 201 202 device_init_wakeup(&client->dev, 0); 203 free_irq(client->irq, ts); 204 input_unregister_device(ts->input_dev); 205 kfree(ts); 206 207 return 0; 208 } 209 210 #ifdef CONFIG_PM 211 static int st1232_ts_suspend(struct device *dev) 212 { 213 struct i2c_client *client = to_i2c_client(dev); 214 215 if (device_may_wakeup(&client->dev)) 216 enable_irq_wake(client->irq); 217 else 218 disable_irq(client->irq); 219 220 return 0; 221 } 222 223 static int st1232_ts_resume(struct device *dev) 224 { 225 struct i2c_client *client = to_i2c_client(dev); 226 227 if (device_may_wakeup(&client->dev)) 228 disable_irq_wake(client->irq); 229 else 230 enable_irq(client->irq); 231 232 return 0; 233 } 234 235 static const struct dev_pm_ops st1232_ts_pm_ops = { 236 .suspend = st1232_ts_suspend, 237 .resume = st1232_ts_resume, 238 }; 239 #endif 240 241 static const struct i2c_device_id st1232_ts_id[] = { 242 { ST1232_TS_NAME, 0 }, 243 { } 244 }; 245 MODULE_DEVICE_TABLE(i2c, st1232_ts_id); 246 247 static struct i2c_driver st1232_ts_driver = { 248 .probe = st1232_ts_probe, 249 .remove = __devexit_p(st1232_ts_remove), 250 .id_table = st1232_ts_id, 251 .driver = { 252 .name = ST1232_TS_NAME, 253 .owner = THIS_MODULE, 254 #ifdef CONFIG_PM 255 .pm = &st1232_ts_pm_ops, 256 #endif 257 }, 258 }; 259 260 static int __init st1232_ts_init(void) 261 { 262 return i2c_add_driver(&st1232_ts_driver); 263 } 264 module_init(st1232_ts_init); 265 266 static void __exit st1232_ts_exit(void) 267 { 268 i2c_del_driver(&st1232_ts_driver); 269 } 270 module_exit(st1232_ts_exit); 271 272 MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>"); 273 MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver"); 274 MODULE_LICENSE("GPL"); 275