1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * TSI driver for Dialog DA9052 4 * 5 * Copyright(c) 2012 Dialog Semiconductor Ltd. 6 * 7 * Author: David Dajun Chen <dchen@diasemi.com> 8 */ 9 #include <linux/module.h> 10 #include <linux/input.h> 11 #include <linux/delay.h> 12 #include <linux/platform_device.h> 13 #include <linux/interrupt.h> 14 15 #include <linux/mfd/da9052/reg.h> 16 #include <linux/mfd/da9052/da9052.h> 17 18 #define TSI_PEN_DOWN_STATUS 0x40 19 20 struct da9052_tsi { 21 struct da9052 *da9052; 22 struct input_dev *dev; 23 struct delayed_work ts_pen_work; 24 bool stopped; 25 bool adc_on; 26 }; 27 28 static void da9052_ts_adc_toggle(struct da9052_tsi *tsi, bool on) 29 { 30 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0, on); 31 tsi->adc_on = on; 32 } 33 34 static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) 35 { 36 struct da9052_tsi *tsi = data; 37 38 if (!tsi->stopped) { 39 /* Mask PEN_DOWN event and unmask TSI_READY event */ 40 da9052_disable_irq_nosync(tsi->da9052, DA9052_IRQ_PENDOWN); 41 da9052_enable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 42 43 da9052_ts_adc_toggle(tsi, true); 44 45 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50); 46 } 47 48 return IRQ_HANDLED; 49 } 50 51 static void da9052_ts_read(struct da9052_tsi *tsi) 52 { 53 struct input_dev *input = tsi->dev; 54 int ret; 55 u16 x, y, z; 56 u8 v; 57 58 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_X_MSB_REG); 59 if (ret < 0) 60 return; 61 62 x = (u16) ret; 63 64 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Y_MSB_REG); 65 if (ret < 0) 66 return; 67 68 y = (u16) ret; 69 70 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_Z_MSB_REG); 71 if (ret < 0) 72 return; 73 74 z = (u16) ret; 75 76 ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG); 77 if (ret < 0) 78 return; 79 80 v = (u8) ret; 81 82 x = ((x << 2) & 0x3fc) | (v & 0x3); 83 y = ((y << 2) & 0x3fc) | ((v & 0xc) >> 2); 84 z = ((z << 2) & 0x3fc) | ((v & 0x30) >> 4); 85 86 input_report_key(input, BTN_TOUCH, 1); 87 input_report_abs(input, ABS_X, x); 88 input_report_abs(input, ABS_Y, y); 89 input_report_abs(input, ABS_PRESSURE, z); 90 input_sync(input); 91 } 92 93 static irqreturn_t da9052_ts_datardy_irq(int irq, void *data) 94 { 95 struct da9052_tsi *tsi = data; 96 97 da9052_ts_read(tsi); 98 99 return IRQ_HANDLED; 100 } 101 102 static void da9052_ts_pen_work(struct work_struct *work) 103 { 104 struct da9052_tsi *tsi = container_of(work, struct da9052_tsi, 105 ts_pen_work.work); 106 if (!tsi->stopped) { 107 int ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG); 108 if (ret < 0 || (ret & TSI_PEN_DOWN_STATUS)) { 109 /* Pen is still DOWN (or read error) */ 110 schedule_delayed_work(&tsi->ts_pen_work, HZ / 50); 111 } else { 112 struct input_dev *input = tsi->dev; 113 114 /* Pen UP */ 115 da9052_ts_adc_toggle(tsi, false); 116 117 /* Report Pen UP */ 118 input_report_key(input, BTN_TOUCH, 0); 119 input_report_abs(input, ABS_PRESSURE, 0); 120 input_sync(input); 121 122 /* 123 * FIXME: Fixes the unhandled irq issue when quick 124 * pen down and pen up events occurs 125 */ 126 ret = da9052_reg_update(tsi->da9052, 127 DA9052_EVENT_B_REG, 0xC0, 0xC0); 128 if (ret < 0) 129 return; 130 131 /* Mask TSI_READY event and unmask PEN_DOWN event */ 132 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 133 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 134 } 135 } 136 } 137 138 static int da9052_ts_configure_gpio(struct da9052 *da9052) 139 { 140 int error; 141 142 error = da9052_reg_update(da9052, DA9052_GPIO_2_3_REG, 0x30, 0); 143 if (error < 0) 144 return error; 145 146 error = da9052_reg_update(da9052, DA9052_GPIO_4_5_REG, 0x33, 0); 147 if (error < 0) 148 return error; 149 150 error = da9052_reg_update(da9052, DA9052_GPIO_6_7_REG, 0x33, 0); 151 if (error < 0) 152 return error; 153 154 return 0; 155 } 156 157 static int da9052_configure_tsi(struct da9052_tsi *tsi) 158 { 159 int error; 160 161 error = da9052_ts_configure_gpio(tsi->da9052); 162 if (error) 163 return error; 164 165 /* Measure TSI sample every 1ms */ 166 error = da9052_reg_update(tsi->da9052, DA9052_ADC_CONT_REG, 167 1 << 6, 1 << 6); 168 if (error < 0) 169 return error; 170 171 /* TSI_DELAY: 3 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */ 172 error = da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 0xFC, 0xC0); 173 if (error < 0) 174 return error; 175 176 /* Supply TSIRef through LD09 */ 177 error = da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x59); 178 if (error < 0) 179 return error; 180 181 return 0; 182 } 183 184 static int da9052_ts_input_open(struct input_dev *input_dev) 185 { 186 struct da9052_tsi *tsi = input_get_drvdata(input_dev); 187 188 tsi->stopped = false; 189 mb(); 190 191 /* Unmask PEN_DOWN event */ 192 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 193 194 /* Enable Pen Detect Circuit */ 195 return da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 196 1 << 1, 1 << 1); 197 } 198 199 static void da9052_ts_input_close(struct input_dev *input_dev) 200 { 201 struct da9052_tsi *tsi = input_get_drvdata(input_dev); 202 203 tsi->stopped = true; 204 mb(); 205 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 206 cancel_delayed_work_sync(&tsi->ts_pen_work); 207 208 if (tsi->adc_on) { 209 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 210 da9052_ts_adc_toggle(tsi, false); 211 212 /* 213 * If ADC was on that means that pendwn IRQ was disabled 214 * twice and we need to enable it to keep enable/disable 215 * counter balanced. IRQ is still off though. 216 */ 217 da9052_enable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 218 } 219 220 /* Disable Pen Detect Circuit */ 221 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0); 222 } 223 224 static int da9052_ts_probe(struct platform_device *pdev) 225 { 226 struct da9052 *da9052; 227 struct da9052_tsi *tsi; 228 struct input_dev *input_dev; 229 int error; 230 231 da9052 = dev_get_drvdata(pdev->dev.parent); 232 if (!da9052) 233 return -EINVAL; 234 235 tsi = kzalloc(sizeof(struct da9052_tsi), GFP_KERNEL); 236 input_dev = input_allocate_device(); 237 if (!tsi || !input_dev) { 238 error = -ENOMEM; 239 goto err_free_mem; 240 } 241 242 tsi->da9052 = da9052; 243 tsi->dev = input_dev; 244 tsi->stopped = true; 245 INIT_DELAYED_WORK(&tsi->ts_pen_work, da9052_ts_pen_work); 246 247 input_dev->id.version = 0x0101; 248 input_dev->id.vendor = 0x15B6; 249 input_dev->id.product = 0x9052; 250 input_dev->name = "Dialog DA9052 TouchScreen Driver"; 251 input_dev->dev.parent = &pdev->dev; 252 input_dev->open = da9052_ts_input_open; 253 input_dev->close = da9052_ts_input_close; 254 255 __set_bit(EV_ABS, input_dev->evbit); 256 __set_bit(EV_KEY, input_dev->evbit); 257 __set_bit(BTN_TOUCH, input_dev->keybit); 258 259 input_set_abs_params(input_dev, ABS_X, 0, 1023, 0, 0); 260 input_set_abs_params(input_dev, ABS_Y, 0, 1023, 0, 0); 261 input_set_abs_params(input_dev, ABS_PRESSURE, 0, 1023, 0, 0); 262 263 input_set_drvdata(input_dev, tsi); 264 265 /* Disable Pen Detect Circuit */ 266 da9052_reg_update(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 1, 0); 267 268 /* Disable ADC */ 269 da9052_ts_adc_toggle(tsi, false); 270 271 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_PENDOWN, 272 "pendown-irq", da9052_ts_pendwn_irq, tsi); 273 if (error) { 274 dev_err(tsi->da9052->dev, 275 "Failed to register PENDWN IRQ: %d\n", error); 276 goto err_free_mem; 277 } 278 279 error = da9052_request_irq(tsi->da9052, DA9052_IRQ_TSIREADY, 280 "tsiready-irq", da9052_ts_datardy_irq, tsi); 281 if (error) { 282 dev_err(tsi->da9052->dev, 283 "Failed to register TSIRDY IRQ :%d\n", error); 284 goto err_free_pendwn_irq; 285 } 286 287 /* Mask PEN_DOWN and TSI_READY events */ 288 da9052_disable_irq(tsi->da9052, DA9052_IRQ_PENDOWN); 289 da9052_disable_irq(tsi->da9052, DA9052_IRQ_TSIREADY); 290 291 error = da9052_configure_tsi(tsi); 292 if (error) 293 goto err_free_datardy_irq; 294 295 error = input_register_device(tsi->dev); 296 if (error) 297 goto err_free_datardy_irq; 298 299 platform_set_drvdata(pdev, tsi); 300 301 return 0; 302 303 err_free_datardy_irq: 304 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi); 305 err_free_pendwn_irq: 306 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi); 307 err_free_mem: 308 kfree(tsi); 309 input_free_device(input_dev); 310 311 return error; 312 } 313 314 static int da9052_ts_remove(struct platform_device *pdev) 315 { 316 struct da9052_tsi *tsi = platform_get_drvdata(pdev); 317 318 da9052_reg_write(tsi->da9052, DA9052_LDO9_REG, 0x19); 319 320 da9052_free_irq(tsi->da9052, DA9052_IRQ_TSIREADY, tsi); 321 da9052_free_irq(tsi->da9052, DA9052_IRQ_PENDOWN, tsi); 322 323 input_unregister_device(tsi->dev); 324 kfree(tsi); 325 326 return 0; 327 } 328 329 static struct platform_driver da9052_tsi_driver = { 330 .probe = da9052_ts_probe, 331 .remove = da9052_ts_remove, 332 .driver = { 333 .name = "da9052-tsi", 334 }, 335 }; 336 337 module_platform_driver(da9052_tsi_driver); 338 339 MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052"); 340 MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>"); 341 MODULE_LICENSE("GPL"); 342 MODULE_ALIAS("platform:da9052-tsi"); 343