1 /* 2 * Touchscreen driver for WM831x PMICs 3 * 4 * Copyright 2011 Wolfson Microelectronics plc. 5 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the 9 * Free Software Foundation; either version 2 of the License, or (at your 10 * option) any later version. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/moduleparam.h> 15 #include <linux/kernel.h> 16 #include <linux/string.h> 17 #include <linux/pm.h> 18 #include <linux/input.h> 19 #include <linux/interrupt.h> 20 #include <linux/io.h> 21 #include <linux/mfd/wm831x/core.h> 22 #include <linux/mfd/wm831x/irq.h> 23 #include <linux/mfd/wm831x/pdata.h> 24 #include <linux/platform_device.h> 25 #include <linux/slab.h> 26 #include <linux/types.h> 27 28 /* 29 * R16424 (0x4028) - Touch Control 1 30 */ 31 #define WM831X_TCH_ENA 0x8000 /* TCH_ENA */ 32 #define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */ 33 #define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */ 34 #define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */ 35 #define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */ 36 #define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */ 37 #define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */ 38 #define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */ 39 #define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */ 40 #define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */ 41 #define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */ 42 #define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */ 43 44 /* 45 * R16425 (0x4029) - Touch Control 2 46 */ 47 #define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */ 48 #define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */ 49 #define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */ 50 #define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */ 51 #define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */ 52 #define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */ 53 #define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */ 54 55 /* 56 * R16426-8 (0x402A-C) - Touch Data X/Y/X 57 */ 58 #define WM831X_TCH_PD 0x8000 /* TCH_PD1 */ 59 #define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */ 60 #define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */ 61 #define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */ 62 63 struct wm831x_ts { 64 struct input_dev *input_dev; 65 struct wm831x *wm831x; 66 unsigned int data_irq; 67 unsigned int pd_irq; 68 bool pressure; 69 bool pen_down; 70 struct work_struct pd_data_work; 71 }; 72 73 static void wm831x_pd_data_work(struct work_struct *work) 74 { 75 struct wm831x_ts *wm831x_ts = 76 container_of(work, struct wm831x_ts, pd_data_work); 77 78 if (wm831x_ts->pen_down) { 79 enable_irq(wm831x_ts->data_irq); 80 dev_dbg(wm831x_ts->wm831x->dev, "IRQ PD->DATA done\n"); 81 } else { 82 enable_irq(wm831x_ts->pd_irq); 83 dev_dbg(wm831x_ts->wm831x->dev, "IRQ DATA->PD done\n"); 84 } 85 } 86 87 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data) 88 { 89 struct wm831x_ts *wm831x_ts = irq_data; 90 struct wm831x *wm831x = wm831x_ts->wm831x; 91 static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE }; 92 u16 data[3]; 93 int count; 94 int i, ret; 95 96 if (wm831x_ts->pressure) 97 count = 3; 98 else 99 count = 2; 100 101 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 102 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 103 104 ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, 105 data); 106 if (ret != 0) { 107 dev_err(wm831x->dev, "Failed to read touch data: %d\n", 108 ret); 109 return IRQ_NONE; 110 } 111 112 /* 113 * We get a pen down reading on every reading, report pen up if any 114 * individual reading does so. 115 */ 116 wm831x_ts->pen_down = true; 117 for (i = 0; i < count; i++) { 118 if (!(data[i] & WM831X_TCH_PD)) { 119 wm831x_ts->pen_down = false; 120 continue; 121 } 122 input_report_abs(wm831x_ts->input_dev, data_types[i], 123 data[i] & WM831X_TCH_DATA_MASK); 124 } 125 126 if (!wm831x_ts->pen_down) { 127 /* Switch from data to pen down */ 128 dev_dbg(wm831x->dev, "IRQ DATA->PD\n"); 129 130 disable_irq_nosync(wm831x_ts->data_irq); 131 132 /* Don't need data any more */ 133 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 134 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 135 WM831X_TCH_Z_ENA, 0); 136 137 /* Flush any final samples that arrived while reading */ 138 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 139 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 140 141 wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data); 142 143 if (wm831x_ts->pressure) 144 input_report_abs(wm831x_ts->input_dev, 145 ABS_PRESSURE, 0); 146 147 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0); 148 149 schedule_work(&wm831x_ts->pd_data_work); 150 } else { 151 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1); 152 } 153 154 input_sync(wm831x_ts->input_dev); 155 156 return IRQ_HANDLED; 157 } 158 159 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data) 160 { 161 struct wm831x_ts *wm831x_ts = irq_data; 162 struct wm831x *wm831x = wm831x_ts->wm831x; 163 int ena = 0; 164 165 if (wm831x_ts->pen_down) 166 return IRQ_HANDLED; 167 168 disable_irq_nosync(wm831x_ts->pd_irq); 169 170 /* Start collecting data */ 171 if (wm831x_ts->pressure) 172 ena |= WM831X_TCH_Z_ENA; 173 174 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 175 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 176 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena); 177 178 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 179 WM831X_TCHPD_EINT, WM831X_TCHPD_EINT); 180 181 wm831x_ts->pen_down = true; 182 183 /* Switch from pen down to data */ 184 dev_dbg(wm831x->dev, "IRQ PD->DATA\n"); 185 schedule_work(&wm831x_ts->pd_data_work); 186 187 return IRQ_HANDLED; 188 } 189 190 static int wm831x_ts_input_open(struct input_dev *idev) 191 { 192 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 193 struct wm831x *wm831x = wm831x_ts->wm831x; 194 195 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 196 WM831X_TCH_ENA | WM831X_TCH_CVT_ENA | 197 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 198 WM831X_TCH_Z_ENA, WM831X_TCH_ENA); 199 200 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 201 WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA); 202 203 return 0; 204 } 205 206 static void wm831x_ts_input_close(struct input_dev *idev) 207 { 208 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 209 struct wm831x *wm831x = wm831x_ts->wm831x; 210 211 /* Shut the controller down, disabling all other functionality too */ 212 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 213 WM831X_TCH_ENA | WM831X_TCH_X_ENA | 214 WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 0); 215 216 /* Make sure any pending IRQs are done, the above will prevent 217 * new ones firing. 218 */ 219 synchronize_irq(wm831x_ts->data_irq); 220 synchronize_irq(wm831x_ts->pd_irq); 221 222 /* Make sure the IRQ completion work is quiesced */ 223 flush_work(&wm831x_ts->pd_data_work); 224 225 /* If we ended up with the pen down then make sure we revert back 226 * to pen detection state for the next time we start up. 227 */ 228 if (wm831x_ts->pen_down) { 229 disable_irq(wm831x_ts->data_irq); 230 enable_irq(wm831x_ts->pd_irq); 231 wm831x_ts->pen_down = false; 232 } 233 } 234 235 static int wm831x_ts_probe(struct platform_device *pdev) 236 { 237 struct wm831x_ts *wm831x_ts; 238 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 239 struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent); 240 struct wm831x_touch_pdata *pdata = NULL; 241 struct input_dev *input_dev; 242 int error, irqf; 243 244 if (core_pdata) 245 pdata = core_pdata->touch; 246 247 wm831x_ts = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_ts), 248 GFP_KERNEL); 249 input_dev = devm_input_allocate_device(&pdev->dev); 250 if (!wm831x_ts || !input_dev) { 251 error = -ENOMEM; 252 goto err_alloc; 253 } 254 255 wm831x_ts->wm831x = wm831x; 256 wm831x_ts->input_dev = input_dev; 257 INIT_WORK(&wm831x_ts->pd_data_work, wm831x_pd_data_work); 258 259 /* 260 * If we have a direct IRQ use it, otherwise use the interrupt 261 * from the WM831x IRQ controller. 262 */ 263 wm831x_ts->data_irq = wm831x_irq(wm831x, 264 platform_get_irq_byname(pdev, 265 "TCHDATA")); 266 if (pdata && pdata->data_irq) 267 wm831x_ts->data_irq = pdata->data_irq; 268 269 wm831x_ts->pd_irq = wm831x_irq(wm831x, 270 platform_get_irq_byname(pdev, "TCHPD")); 271 if (pdata && pdata->pd_irq) 272 wm831x_ts->pd_irq = pdata->pd_irq; 273 274 if (pdata) 275 wm831x_ts->pressure = pdata->pressure; 276 else 277 wm831x_ts->pressure = true; 278 279 /* Five wire touchscreens can't report pressure */ 280 if (pdata && pdata->fivewire) { 281 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 282 WM831X_TCH_5WIRE, WM831X_TCH_5WIRE); 283 284 /* Pressure measurements are not possible for five wire mode */ 285 WARN_ON(pdata->pressure && pdata->fivewire); 286 wm831x_ts->pressure = false; 287 } else { 288 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 289 WM831X_TCH_5WIRE, 0); 290 } 291 292 if (pdata) { 293 switch (pdata->isel) { 294 default: 295 dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n", 296 pdata->isel); 297 /* Fall through */ 298 case 200: 299 case 0: 300 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 301 WM831X_TCH_ISEL, 0); 302 break; 303 case 400: 304 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 305 WM831X_TCH_ISEL, WM831X_TCH_ISEL); 306 break; 307 } 308 } 309 310 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 311 WM831X_TCH_PDONLY, 0); 312 313 /* Default to 96 samples/sec */ 314 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 315 WM831X_TCH_RATE_MASK, 6); 316 317 if (pdata && pdata->data_irqf) 318 irqf = pdata->data_irqf; 319 else 320 irqf = IRQF_TRIGGER_HIGH; 321 322 error = request_threaded_irq(wm831x_ts->data_irq, 323 NULL, wm831x_ts_data_irq, 324 irqf | IRQF_ONESHOT, 325 "Touchscreen data", wm831x_ts); 326 if (error) { 327 dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n", 328 wm831x_ts->data_irq, error); 329 goto err_alloc; 330 } 331 disable_irq(wm831x_ts->data_irq); 332 333 if (pdata && pdata->pd_irqf) 334 irqf = pdata->pd_irqf; 335 else 336 irqf = IRQF_TRIGGER_HIGH; 337 338 error = request_threaded_irq(wm831x_ts->pd_irq, 339 NULL, wm831x_ts_pen_down_irq, 340 irqf | IRQF_ONESHOT, 341 "Touchscreen pen down", wm831x_ts); 342 if (error) { 343 dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n", 344 wm831x_ts->pd_irq, error); 345 goto err_data_irq; 346 } 347 348 /* set up touch configuration */ 349 input_dev->name = "WM831x touchscreen"; 350 input_dev->phys = "wm831x"; 351 input_dev->open = wm831x_ts_input_open; 352 input_dev->close = wm831x_ts_input_close; 353 354 __set_bit(EV_ABS, input_dev->evbit); 355 __set_bit(EV_KEY, input_dev->evbit); 356 __set_bit(BTN_TOUCH, input_dev->keybit); 357 358 input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0); 359 input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0); 360 if (wm831x_ts->pressure) 361 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0); 362 363 input_set_drvdata(input_dev, wm831x_ts); 364 input_dev->dev.parent = &pdev->dev; 365 366 error = input_register_device(input_dev); 367 if (error) 368 goto err_pd_irq; 369 370 platform_set_drvdata(pdev, wm831x_ts); 371 return 0; 372 373 err_pd_irq: 374 free_irq(wm831x_ts->pd_irq, wm831x_ts); 375 err_data_irq: 376 free_irq(wm831x_ts->data_irq, wm831x_ts); 377 err_alloc: 378 379 return error; 380 } 381 382 static int wm831x_ts_remove(struct platform_device *pdev) 383 { 384 struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev); 385 386 free_irq(wm831x_ts->pd_irq, wm831x_ts); 387 free_irq(wm831x_ts->data_irq, wm831x_ts); 388 389 return 0; 390 } 391 392 static struct platform_driver wm831x_ts_driver = { 393 .driver = { 394 .name = "wm831x-touch", 395 }, 396 .probe = wm831x_ts_probe, 397 .remove = wm831x_ts_remove, 398 }; 399 module_platform_driver(wm831x_ts_driver); 400 401 /* Module information */ 402 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 403 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver"); 404 MODULE_LICENSE("GPL"); 405 MODULE_ALIAS("platform:wm831x-touch"); 406