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/gpio.h> 23 #include <linux/i2c.h> 24 #include <linux/input.h> 25 #include <linux/interrupt.h> 26 #include <linux/module.h> 27 #include <linux/of.h> 28 #include <linux/of_gpio.h> 29 #include <linux/pm_qos.h> 30 #include <linux/slab.h> 31 #include <linux/types.h> 32 #include <linux/platform_data/st1232_pdata.h> 33 34 #define ST1232_TS_NAME "st1232-ts" 35 36 #define MIN_X 0x00 37 #define MIN_Y 0x00 38 #define MAX_X 0x31f /* (800 - 1) */ 39 #define MAX_Y 0x1df /* (480 - 1) */ 40 #define MAX_AREA 0xff 41 #define MAX_FINGERS 2 42 43 struct st1232_ts_finger { 44 u16 x; 45 u16 y; 46 u8 t; 47 bool is_valid; 48 }; 49 50 struct st1232_ts_data { 51 struct i2c_client *client; 52 struct input_dev *input_dev; 53 struct st1232_ts_finger finger[MAX_FINGERS]; 54 struct dev_pm_qos_request low_latency_req; 55 int reset_gpio; 56 }; 57 58 static int st1232_ts_read_data(struct st1232_ts_data *ts) 59 { 60 struct st1232_ts_finger *finger = ts->finger; 61 struct i2c_client *client = ts->client; 62 struct i2c_msg msg[2]; 63 int error; 64 u8 start_reg; 65 u8 buf[10]; 66 67 /* read touchscreen data from ST1232 */ 68 msg[0].addr = client->addr; 69 msg[0].flags = 0; 70 msg[0].len = 1; 71 msg[0].buf = &start_reg; 72 start_reg = 0x10; 73 74 msg[1].addr = ts->client->addr; 75 msg[1].flags = I2C_M_RD; 76 msg[1].len = sizeof(buf); 77 msg[1].buf = buf; 78 79 error = i2c_transfer(client->adapter, msg, 2); 80 if (error < 0) 81 return error; 82 83 /* get "valid" bits */ 84 finger[0].is_valid = buf[2] >> 7; 85 finger[1].is_valid = buf[5] >> 7; 86 87 /* get xy coordinate */ 88 if (finger[0].is_valid) { 89 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3]; 90 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4]; 91 finger[0].t = buf[8]; 92 } 93 94 if (finger[1].is_valid) { 95 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6]; 96 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7]; 97 finger[1].t = buf[9]; 98 } 99 100 return 0; 101 } 102 103 static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id) 104 { 105 struct st1232_ts_data *ts = dev_id; 106 struct st1232_ts_finger *finger = ts->finger; 107 struct input_dev *input_dev = ts->input_dev; 108 int count = 0; 109 int i, ret; 110 111 ret = st1232_ts_read_data(ts); 112 if (ret < 0) 113 goto end; 114 115 /* multi touch protocol */ 116 for (i = 0; i < MAX_FINGERS; i++) { 117 if (!finger[i].is_valid) 118 continue; 119 120 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t); 121 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x); 122 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y); 123 input_mt_sync(input_dev); 124 count++; 125 } 126 127 /* SYN_MT_REPORT only if no contact */ 128 if (!count) { 129 input_mt_sync(input_dev); 130 if (ts->low_latency_req.dev) { 131 dev_pm_qos_remove_request(&ts->low_latency_req); 132 ts->low_latency_req.dev = NULL; 133 } 134 } else if (!ts->low_latency_req.dev) { 135 /* First contact, request 100 us latency. */ 136 dev_pm_qos_add_ancestor_request(&ts->client->dev, 137 &ts->low_latency_req, 138 DEV_PM_QOS_RESUME_LATENCY, 100); 139 } 140 141 /* SYN_REPORT */ 142 input_sync(input_dev); 143 144 end: 145 return IRQ_HANDLED; 146 } 147 148 static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron) 149 { 150 if (gpio_is_valid(ts->reset_gpio)) 151 gpio_direction_output(ts->reset_gpio, poweron); 152 } 153 154 static int st1232_ts_probe(struct i2c_client *client, 155 const struct i2c_device_id *id) 156 { 157 struct st1232_ts_data *ts; 158 struct st1232_pdata *pdata = dev_get_platdata(&client->dev); 159 struct input_dev *input_dev; 160 int error; 161 162 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 163 dev_err(&client->dev, "need I2C_FUNC_I2C\n"); 164 return -EIO; 165 } 166 167 if (!client->irq) { 168 dev_err(&client->dev, "no IRQ?\n"); 169 return -EINVAL; 170 } 171 172 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL); 173 if (!ts) 174 return -ENOMEM; 175 176 input_dev = devm_input_allocate_device(&client->dev); 177 if (!input_dev) 178 return -ENOMEM; 179 180 ts->client = client; 181 ts->input_dev = input_dev; 182 183 if (pdata) 184 ts->reset_gpio = pdata->reset_gpio; 185 else if (client->dev.of_node) 186 ts->reset_gpio = of_get_gpio(client->dev.of_node, 0); 187 else 188 ts->reset_gpio = -ENODEV; 189 190 if (gpio_is_valid(ts->reset_gpio)) { 191 error = devm_gpio_request(&client->dev, ts->reset_gpio, NULL); 192 if (error) { 193 dev_err(&client->dev, 194 "Unable to request GPIO pin %d.\n", 195 ts->reset_gpio); 196 return error; 197 } 198 } 199 200 st1232_ts_power(ts, true); 201 202 input_dev->name = "st1232-touchscreen"; 203 input_dev->id.bustype = BUS_I2C; 204 input_dev->dev.parent = &client->dev; 205 206 __set_bit(EV_SYN, input_dev->evbit); 207 __set_bit(EV_KEY, input_dev->evbit); 208 __set_bit(EV_ABS, input_dev->evbit); 209 210 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0); 211 input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0); 212 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0); 213 214 error = devm_request_threaded_irq(&client->dev, client->irq, 215 NULL, st1232_ts_irq_handler, 216 IRQF_ONESHOT, 217 client->name, ts); 218 if (error) { 219 dev_err(&client->dev, "Failed to register interrupt\n"); 220 return error; 221 } 222 223 error = input_register_device(ts->input_dev); 224 if (error) { 225 dev_err(&client->dev, "Unable to register %s input device\n", 226 input_dev->name); 227 return error; 228 } 229 230 i2c_set_clientdata(client, ts); 231 device_init_wakeup(&client->dev, 1); 232 233 return 0; 234 } 235 236 static int st1232_ts_remove(struct i2c_client *client) 237 { 238 struct st1232_ts_data *ts = i2c_get_clientdata(client); 239 240 device_init_wakeup(&client->dev, 0); 241 st1232_ts_power(ts, false); 242 243 return 0; 244 } 245 246 static int __maybe_unused st1232_ts_suspend(struct device *dev) 247 { 248 struct i2c_client *client = to_i2c_client(dev); 249 struct st1232_ts_data *ts = i2c_get_clientdata(client); 250 251 if (device_may_wakeup(&client->dev)) { 252 enable_irq_wake(client->irq); 253 } else { 254 disable_irq(client->irq); 255 st1232_ts_power(ts, false); 256 } 257 258 return 0; 259 } 260 261 static int __maybe_unused st1232_ts_resume(struct device *dev) 262 { 263 struct i2c_client *client = to_i2c_client(dev); 264 struct st1232_ts_data *ts = i2c_get_clientdata(client); 265 266 if (device_may_wakeup(&client->dev)) { 267 disable_irq_wake(client->irq); 268 } else { 269 st1232_ts_power(ts, true); 270 enable_irq(client->irq); 271 } 272 273 return 0; 274 } 275 276 static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops, 277 st1232_ts_suspend, st1232_ts_resume); 278 279 static const struct i2c_device_id st1232_ts_id[] = { 280 { ST1232_TS_NAME, 0 }, 281 { } 282 }; 283 MODULE_DEVICE_TABLE(i2c, st1232_ts_id); 284 285 #ifdef CONFIG_OF 286 static const struct of_device_id st1232_ts_dt_ids[] = { 287 { .compatible = "sitronix,st1232", }, 288 { } 289 }; 290 MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids); 291 #endif 292 293 static struct i2c_driver st1232_ts_driver = { 294 .probe = st1232_ts_probe, 295 .remove = st1232_ts_remove, 296 .id_table = st1232_ts_id, 297 .driver = { 298 .name = ST1232_TS_NAME, 299 .of_match_table = of_match_ptr(st1232_ts_dt_ids), 300 .pm = &st1232_ts_pm_ops, 301 }, 302 }; 303 304 module_i2c_driver(st1232_ts_driver); 305 306 MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>"); 307 MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver"); 308 MODULE_LICENSE("GPL"); 309