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/init.h> 17 #include <linux/string.h> 18 #include <linux/pm.h> 19 #include <linux/input.h> 20 #include <linux/interrupt.h> 21 #include <linux/io.h> 22 #include <linux/mfd/wm831x/core.h> 23 #include <linux/mfd/wm831x/irq.h> 24 #include <linux/mfd/wm831x/pdata.h> 25 #include <linux/platform_device.h> 26 #include <linux/slab.h> 27 #include <linux/types.h> 28 29 /* 30 * R16424 (0x4028) - Touch Control 1 31 */ 32 #define WM831X_TCH_ENA 0x8000 /* TCH_ENA */ 33 #define WM831X_TCH_CVT_ENA 0x4000 /* TCH_CVT_ENA */ 34 #define WM831X_TCH_SLPENA 0x1000 /* TCH_SLPENA */ 35 #define WM831X_TCH_Z_ENA 0x0400 /* TCH_Z_ENA */ 36 #define WM831X_TCH_Y_ENA 0x0200 /* TCH_Y_ENA */ 37 #define WM831X_TCH_X_ENA 0x0100 /* TCH_X_ENA */ 38 #define WM831X_TCH_DELAY_MASK 0x00E0 /* TCH_DELAY - [7:5] */ 39 #define WM831X_TCH_DELAY_SHIFT 5 /* TCH_DELAY - [7:5] */ 40 #define WM831X_TCH_DELAY_WIDTH 3 /* TCH_DELAY - [7:5] */ 41 #define WM831X_TCH_RATE_MASK 0x001F /* TCH_RATE - [4:0] */ 42 #define WM831X_TCH_RATE_SHIFT 0 /* TCH_RATE - [4:0] */ 43 #define WM831X_TCH_RATE_WIDTH 5 /* TCH_RATE - [4:0] */ 44 45 /* 46 * R16425 (0x4029) - Touch Control 2 47 */ 48 #define WM831X_TCH_PD_WK 0x2000 /* TCH_PD_WK */ 49 #define WM831X_TCH_5WIRE 0x1000 /* TCH_5WIRE */ 50 #define WM831X_TCH_PDONLY 0x0800 /* TCH_PDONLY */ 51 #define WM831X_TCH_ISEL 0x0100 /* TCH_ISEL */ 52 #define WM831X_TCH_RPU_MASK 0x000F /* TCH_RPU - [3:0] */ 53 #define WM831X_TCH_RPU_SHIFT 0 /* TCH_RPU - [3:0] */ 54 #define WM831X_TCH_RPU_WIDTH 4 /* TCH_RPU - [3:0] */ 55 56 /* 57 * R16426-8 (0x402A-C) - Touch Data X/Y/X 58 */ 59 #define WM831X_TCH_PD 0x8000 /* TCH_PD1 */ 60 #define WM831X_TCH_DATA_MASK 0x0FFF /* TCH_DATA - [11:0] */ 61 #define WM831X_TCH_DATA_SHIFT 0 /* TCH_DATA - [11:0] */ 62 #define WM831X_TCH_DATA_WIDTH 12 /* TCH_DATA - [11:0] */ 63 64 struct wm831x_ts { 65 struct input_dev *input_dev; 66 struct wm831x *wm831x; 67 unsigned int data_irq; 68 unsigned int pd_irq; 69 bool pressure; 70 bool pen_down; 71 }; 72 73 static irqreturn_t wm831x_ts_data_irq(int irq, void *irq_data) 74 { 75 struct wm831x_ts *wm831x_ts = irq_data; 76 struct wm831x *wm831x = wm831x_ts->wm831x; 77 static int data_types[] = { ABS_X, ABS_Y, ABS_PRESSURE }; 78 u16 data[3]; 79 int count; 80 int i, ret; 81 82 if (wm831x_ts->pressure) 83 count = 3; 84 else 85 count = 2; 86 87 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 88 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 89 90 ret = wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, 91 data); 92 if (ret != 0) { 93 dev_err(wm831x->dev, "Failed to read touch data: %d\n", 94 ret); 95 return IRQ_NONE; 96 } 97 98 /* 99 * We get a pen down reading on every reading, report pen up if any 100 * individual reading does so. 101 */ 102 wm831x_ts->pen_down = true; 103 for (i = 0; i < count; i++) { 104 if (!(data[i] & WM831X_TCH_PD)) { 105 wm831x_ts->pen_down = false; 106 continue; 107 } 108 input_report_abs(wm831x_ts->input_dev, data_types[i], 109 data[i] & WM831X_TCH_DATA_MASK); 110 } 111 112 if (!wm831x_ts->pen_down) { 113 disable_irq_nosync(wm831x_ts->data_irq); 114 115 /* Don't need data any more */ 116 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 117 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 118 WM831X_TCH_Z_ENA, 0); 119 120 /* Flush any final samples that arrived while reading */ 121 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 122 WM831X_TCHDATA_EINT, WM831X_TCHDATA_EINT); 123 124 wm831x_bulk_read(wm831x, WM831X_TOUCH_DATA_X, count, data); 125 126 if (wm831x_ts->pressure) 127 input_report_abs(wm831x_ts->input_dev, 128 ABS_PRESSURE, 0); 129 130 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 0); 131 } 132 133 input_sync(wm831x_ts->input_dev); 134 135 return IRQ_HANDLED; 136 } 137 138 static irqreturn_t wm831x_ts_pen_down_irq(int irq, void *irq_data) 139 { 140 struct wm831x_ts *wm831x_ts = irq_data; 141 struct wm831x *wm831x = wm831x_ts->wm831x; 142 int ena = 0; 143 144 /* Start collecting data */ 145 if (wm831x_ts->pressure) 146 ena |= WM831X_TCH_Z_ENA; 147 148 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 149 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | WM831X_TCH_Z_ENA, 150 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | ena); 151 152 input_report_key(wm831x_ts->input_dev, BTN_TOUCH, 1); 153 input_sync(wm831x_ts->input_dev); 154 155 wm831x_set_bits(wm831x, WM831X_INTERRUPT_STATUS_1, 156 WM831X_TCHPD_EINT, WM831X_TCHPD_EINT); 157 158 wm831x_ts->pen_down = true; 159 enable_irq(wm831x_ts->data_irq); 160 161 return IRQ_HANDLED; 162 } 163 164 static int wm831x_ts_input_open(struct input_dev *idev) 165 { 166 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 167 struct wm831x *wm831x = wm831x_ts->wm831x; 168 169 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 170 WM831X_TCH_ENA | WM831X_TCH_CVT_ENA | 171 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 172 WM831X_TCH_Z_ENA, WM831X_TCH_ENA); 173 174 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 175 WM831X_TCH_CVT_ENA, WM831X_TCH_CVT_ENA); 176 177 return 0; 178 } 179 180 static void wm831x_ts_input_close(struct input_dev *idev) 181 { 182 struct wm831x_ts *wm831x_ts = input_get_drvdata(idev); 183 struct wm831x *wm831x = wm831x_ts->wm831x; 184 185 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 186 WM831X_TCH_ENA | WM831X_TCH_CVT_ENA | 187 WM831X_TCH_X_ENA | WM831X_TCH_Y_ENA | 188 WM831X_TCH_Z_ENA, 0); 189 190 if (wm831x_ts->pen_down) 191 disable_irq(wm831x_ts->data_irq); 192 } 193 194 static __devinit int wm831x_ts_probe(struct platform_device *pdev) 195 { 196 struct wm831x_ts *wm831x_ts; 197 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 198 struct wm831x_pdata *core_pdata = dev_get_platdata(pdev->dev.parent); 199 struct wm831x_touch_pdata *pdata = NULL; 200 struct input_dev *input_dev; 201 int error; 202 203 if (core_pdata) 204 pdata = core_pdata->touch; 205 206 wm831x_ts = kzalloc(sizeof(struct wm831x_ts), GFP_KERNEL); 207 input_dev = input_allocate_device(); 208 if (!wm831x_ts || !input_dev) { 209 error = -ENOMEM; 210 goto err_alloc; 211 } 212 213 wm831x_ts->wm831x = wm831x; 214 wm831x_ts->input_dev = input_dev; 215 216 /* 217 * If we have a direct IRQ use it, otherwise use the interrupt 218 * from the WM831x IRQ controller. 219 */ 220 if (pdata && pdata->data_irq) 221 wm831x_ts->data_irq = pdata->data_irq; 222 else 223 wm831x_ts->data_irq = platform_get_irq_byname(pdev, "TCHDATA"); 224 225 if (pdata && pdata->pd_irq) 226 wm831x_ts->pd_irq = pdata->pd_irq; 227 else 228 wm831x_ts->pd_irq = platform_get_irq_byname(pdev, "TCHPD"); 229 230 if (pdata) 231 wm831x_ts->pressure = pdata->pressure; 232 else 233 wm831x_ts->pressure = true; 234 235 /* Five wire touchscreens can't report pressure */ 236 if (pdata && pdata->fivewire) { 237 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 238 WM831X_TCH_5WIRE, WM831X_TCH_5WIRE); 239 240 /* Pressure measurements are not possible for five wire mode */ 241 WARN_ON(pdata->pressure && pdata->fivewire); 242 wm831x_ts->pressure = false; 243 } else { 244 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 245 WM831X_TCH_5WIRE, 0); 246 } 247 248 if (pdata) { 249 switch (pdata->isel) { 250 default: 251 dev_err(&pdev->dev, "Unsupported ISEL setting: %d\n", 252 pdata->isel); 253 /* Fall through */ 254 case 200: 255 case 0: 256 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 257 WM831X_TCH_ISEL, 0); 258 break; 259 case 400: 260 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 261 WM831X_TCH_ISEL, WM831X_TCH_ISEL); 262 break; 263 } 264 } 265 266 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_2, 267 WM831X_TCH_PDONLY, 0); 268 269 /* Default to 96 samples/sec */ 270 wm831x_set_bits(wm831x, WM831X_TOUCH_CONTROL_1, 271 WM831X_TCH_RATE_MASK, 6); 272 273 error = request_threaded_irq(wm831x_ts->data_irq, 274 NULL, wm831x_ts_data_irq, 275 IRQF_ONESHOT, 276 "Touchscreen data", wm831x_ts); 277 if (error) { 278 dev_err(&pdev->dev, "Failed to request data IRQ %d: %d\n", 279 wm831x_ts->data_irq, error); 280 goto err_alloc; 281 } 282 disable_irq(wm831x_ts->data_irq); 283 284 error = request_threaded_irq(wm831x_ts->pd_irq, 285 NULL, wm831x_ts_pen_down_irq, 286 IRQF_ONESHOT, 287 "Touchscreen pen down", wm831x_ts); 288 if (error) { 289 dev_err(&pdev->dev, "Failed to request pen down IRQ %d: %d\n", 290 wm831x_ts->pd_irq, error); 291 goto err_data_irq; 292 } 293 294 /* set up touch configuration */ 295 input_dev->name = "WM831x touchscreen"; 296 input_dev->phys = "wm831x"; 297 input_dev->open = wm831x_ts_input_open; 298 input_dev->close = wm831x_ts_input_close; 299 300 __set_bit(EV_ABS, input_dev->evbit); 301 __set_bit(EV_KEY, input_dev->evbit); 302 __set_bit(BTN_TOUCH, input_dev->keybit); 303 304 input_set_abs_params(input_dev, ABS_X, 0, 4095, 5, 0); 305 input_set_abs_params(input_dev, ABS_Y, 0, 4095, 5, 0); 306 if (wm831x_ts->pressure) 307 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 4095, 5, 0); 308 309 input_set_drvdata(input_dev, wm831x_ts); 310 input_dev->dev.parent = &pdev->dev; 311 312 error = input_register_device(input_dev); 313 if (error) 314 goto err_pd_irq; 315 316 platform_set_drvdata(pdev, wm831x_ts); 317 return 0; 318 319 err_pd_irq: 320 free_irq(wm831x_ts->pd_irq, wm831x_ts); 321 err_data_irq: 322 free_irq(wm831x_ts->data_irq, wm831x_ts); 323 err_alloc: 324 input_free_device(input_dev); 325 kfree(wm831x_ts); 326 327 return error; 328 } 329 330 static __devexit int wm831x_ts_remove(struct platform_device *pdev) 331 { 332 struct wm831x_ts *wm831x_ts = platform_get_drvdata(pdev); 333 334 free_irq(wm831x_ts->pd_irq, wm831x_ts); 335 free_irq(wm831x_ts->data_irq, wm831x_ts); 336 input_unregister_device(wm831x_ts->input_dev); 337 kfree(wm831x_ts); 338 339 platform_set_drvdata(pdev, NULL); 340 return 0; 341 } 342 343 static struct platform_driver wm831x_ts_driver = { 344 .driver = { 345 .name = "wm831x-touch", 346 .owner = THIS_MODULE, 347 }, 348 .probe = wm831x_ts_probe, 349 .remove = __devexit_p(wm831x_ts_remove), 350 }; 351 352 static int __init wm831x_ts_init(void) 353 { 354 return platform_driver_register(&wm831x_ts_driver); 355 } 356 module_init(wm831x_ts_init); 357 358 static void __exit wm831x_ts_exit(void) 359 { 360 platform_driver_unregister(&wm831x_ts_driver); 361 } 362 module_exit(wm831x_ts_exit); 363 364 /* Module information */ 365 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 366 MODULE_DESCRIPTION("WM831x PMIC touchscreen driver"); 367 MODULE_LICENSE("GPL"); 368 MODULE_ALIAS("platform:wm831x-touch"); 369