1 /* 2 * TSI driver for Dialog DA9052 3 * 4 * Copyright(c) 2012 Dialog Semiconductor Ltd. 5 * 6 * Author: David Dajun Chen <dchen@diasemi.com> 7 * 8 * This program is free software; you can redistribute it and/or modify it 9 * under the terms of the GNU General Public License as published by the 10 * Free Software Foundation; either version 2 of the License, or (at your 11 * option) any later version. 12 * 13 */ 14 #include <linux/module.h> 15 #include <linux/input.h> 16 #include <linux/delay.h> 17 #include <linux/platform_device.h> 18 #include <linux/interrupt.h> 19 20 #include <linux/mfd/da9052/reg.h> 21 #include <linux/mfd/da9052/da9052.h> 22 23 #define TSI_PEN_DOWN_STATUS 0x40 24 25 struct da9052_tsi { 26 struct da9052 *da9052; 27 struct input_dev *dev; 28 struct delayed_work ts_pen_work; 29 bool stopped; 30 bool adc_on; 31 }; 32 33 static void da9052_ts_adc_toggle(struct da9052_tsi *tsi, bool on) 34 { 35 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0, on); 36 tsi->adc_on = on; 37 } 38 39 static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) 40 { 41 struct da9052_tsi *tsi = data; 42 43 if (!tsi->stopped) { 44 /* Mask PEN_DOWN event and unmask TSI_READY event */ 45 da9052_disable_irq_nosync(tsi->da9052, DA9052_IRQ_PENDOWN); 46 da9052_enable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 47 48 da9052_ts_adc_toggle(tsi, true); 49 50 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50); 51 } 52 53 return IRQ_HANDLED; 54 } 55 56 static void da9052_ts_read(struct da9052_tsi *tsi) 57 { 58 struct input_dev *input = tsi->dev; 59 int ret; 60 u16 x, y, z; 61 u8 v; 62 63 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_X_MSB_REG); 64 if (ret < 0) 65 return; 66 67 x = (u16) ret; 68 69 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Y_MSB_REG); 70 if (ret < 0) 71 return; 72 73 y = (u16) ret; 74 75 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Z_MSB_REG); 76 if (ret < 0) 77 return; 78 79 z = (u16) ret; 80 81 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG); 82 if (ret < 0) 83 return; 84 85 v = (u8) ret; 86 87 x = ((x << 2) & 0x3fc) | (v & 0x3); 88 y = ((y << 2) & 0x3fc) | ((v & 0xc) >> 2); 89 z = ((z << 2) & 0x3fc) | ((v & 0x30) >> 4); 90 91 input_report_key(input, BTN_TOUCH, 1); 92 input_report_abs(input, ABS_X, x); 93 input_report_abs(input, ABS_Y, y); 94 input_report_abs(input, ABS_PRESSURE, z); 95 input_sync(input); 96 } 97 98 static irqreturn_t da9052_ts_datardy_irq(int irq, void *data) 99 { 100 struct da9052_tsi *tsi = data; 101 102 da9052_ts_read(tsi); 103 104 return IRQ_HANDLED; 105 } 106 107 static void da9052_ts_pen_work(struct work_struct *work) 108 { 109 struct da9052_tsi *tsi = container_of(work, struct da9052_tsi, 110 ts_pen_work.work); 111 if (!tsi->stopped) { 112 int ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG); 113 if (ret < 0 || (ret & TSI_PEN_DOWN_STATUS)) { 114 /* Pen is still DOWN (or read error) */ 115 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50); 116 } else { 117 struct input_dev *input = tsi->dev; 118 119 /* Pen UP */ 120 da9052_ts_adc_toggle(tsi, false); 121 122 /* Report Pen UP */ 123 input_report_key(input, BTN_TOUCH, 0); 124 input_report_abs(input, ABS_PRESSURE, 0); 125 input_sync(input); 126 127 /* 128 * FIXME: Fixes the unhandled irq issue when quick 129 * pen down and pen up events occurs 130 */ 131 ret = da9052_reg_update(tsi->da9052, 132 DA9052_EVENT_B_REG, 0xC0, 0xC0); 133 if (ret < 0) 134 return; 135 136 /* Mask TSI_READY event and unmask PEN_DOWN event */ 137 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 138 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 139 } 140 } 141 } 142 143 static int da9052_ts_configure_gpio(struct da9052 *da9052) 144 { 145 int error; 146 147 error = da9052_reg_update(da9052, DA9052_GPIO_2_3_REG, 0x30, 0); 148 if (error < 0) 149 return error; 150 151 error = da9052_reg_update(da9052, DA9052_GPIO_4_5_REG, 0x33, 0); 152 if (error < 0) 153 return error; 154 155 error = da9052_reg_update(da9052, DA9052_GPIO_6_7_REG, 0x33, 0); 156 if (error < 0) 157 return error; 158 159 return 0; 160 } 161 162 static int da9052_configure_tsi(struct da9052_tsi *tsi) 163 { 164 int error; 165 166 error = da9052_ts_configure_gpio(tsi->da9052); 167 if (error) 168 return error; 169 170 /* Measure TSI sample every 1ms */ 171 error = da9052_reg_update(tsi->da9052, DA9052_ADC_CONT_REG, 172 1 << 6, 1 << 6); 173 if (error < 0) 174 return error; 175 176 /* TSI_DELAY: 3 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */ 177 error = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 0xFC, 0xC0); 178 if (error < 0) 179 return error; 180 181 /* Supply TSIRef through LD09 */ 182 error = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x59); 183 if (error < 0) 184 return error; 185 186 return 0; 187 } 188 189 static int da9052_ts_input_open(struct input_dev *input_dev) 190 { 191 struct da9052_tsi *tsi = input_get_drvdata(input_dev); 192 193 tsi->stopped = false; 194 mb(); 195 196 /* Unmask PEN_DOWN event */ 197 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 198 199 /* Enable Pen Detect Circuit */ 200 return da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 201 1 << 1, 1 << 1); 202 } 203 204 static void da9052_ts_input_close(struct input_dev *input_dev) 205 { 206 struct da9052_tsi *tsi = input_get_drvdata(input_dev); 207 208 tsi->stopped = true; 209 mb(); 210 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 211 cancel_delayed_work_sync(&tsi->ts_pen_work); 212 213 if (tsi->adc_on) { 214 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 215 da9052_ts_adc_toggle(tsi, false); 216 217 /* 218 * If ADC was on that means that pendwn IRQ was disabled 219 * twice and we need to enable it to keep enable/disable 220 * counter balanced. IRQ is still off though. 221 */ 222 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 223 } 224 225 /* Disable Pen Detect Circuit */ 226 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0); 227 } 228 229 static int da9052_ts_probe(struct platform_device *pdev) 230 { 231 struct da9052 *da9052; 232 struct da9052_tsi *tsi; 233 struct input_dev *input_dev; 234 int error; 235 236 da9052 = dev_get_drvdata(pdev->dev.parent); 237 if (!da9052) 238 return -EINVAL; 239 240 tsi = kzalloc(sizeof(struct da9052_tsi), GFP_KERNEL); 241 input_dev = input_allocate_device(); 242 if (!tsi || !input_dev) { 243 error = -ENOMEM; 244 goto err_free_mem; 245 } 246 247 tsi->da9052 = da9052; 248 tsi->dev = input_dev; 249 tsi->stopped = true; 250 INIT_DELAYED_WORK(&tsi->ts_pen_work, da9052_ts_pen_work); 251 252 input_dev->id.version = 0x0101; 253 input_dev->id.vendor = 0x15B6; 254 input_dev->id.product = 0x9052; 255 input_dev->name = "Dialog DA9052 TouchScreen Driver"; 256 input_dev->dev.parent = &pdev->dev; 257 input_dev->open = da9052_ts_input_open; 258 input_dev->close = da9052_ts_input_close; 259 260 __set_bit(EV_ABS, input_dev->evbit); 261 __set_bit(EV_KEY, input_dev->evbit); 262 __set_bit(BTN_TOUCH, input_dev->keybit); 263 264 input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0); 265 input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0); 266 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 1023, 0, 0); 267 268 input_set_drvdata(input_dev, tsi); 269 270 /* Disable Pen Detect Circuit */ 271 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0); 272 273 /* Disable ADC */ 274 da9052_ts_adc_toggle(tsi, false); 275 276 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_PENDOWN, 277 "pendown-irq", da9052_ts_pendwn_irq, tsi); 278 if (error) { 279 dev_err(tsi->da9052->dev, 280 "Failed to register PENDWN IRQ: %d\n", error); 281 goto err_free_mem; 282 } 283 284 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_TSIREADY, 285 "tsiready-irq", da9052_ts_datardy_irq, tsi); 286 if (error) { 287 dev_err(tsi->da9052->dev, 288 "Failed to register TSIRDY IRQ :%d\n", error); 289 goto err_free_pendwn_irq; 290 } 291 292 /* Mask PEN_DOWN and TSI_READY events */ 293 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 294 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 295 296 error = da9052_configure_tsi(tsi); 297 if (error) 298 goto err_free_datardy_irq; 299 300 error = input_register_device(tsi->dev); 301 if (error) 302 goto err_free_datardy_irq; 303 304 platform_set_drvdata(pdev, tsi); 305 306 return 0; 307 308 err_free_datardy_irq: 309 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi); 310 err_free_pendwn_irq: 311 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi); 312 err_free_mem: 313 kfree(tsi); 314 input_free_device(input_dev); 315 316 return error; 317 } 318 319 static int da9052_ts_remove(struct platform_device *pdev) 320 { 321 struct da9052_tsi *tsi = platform_get_drvdata(pdev); 322 323 da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x19); 324 325 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi); 326 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi); 327 328 input_unregister_device(tsi->dev); 329 kfree(tsi); 330 331 return 0; 332 } 333 334 static struct platform_driver da9052_tsi_driver = { 335 .probe = da9052_ts_probe, 336 .remove = da9052_ts_remove, 337 .driver = { 338 .name = "da9052-tsi", 339 }, 340 }; 341 342 module_platform_driver(da9052_tsi_driver); 343 344 MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052"); 345 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>"); 346 MODULE_LICENSE("GPL"); 347 MODULE_ALIAS("platform:da9052-tsi"); 348