1 /* 2 * Allwinner sunxi resistive touchscreen controller driver 3 * 4 * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com> 5 * 6 * The hwmon parts are based on work by Corentin LABBE which is: 7 * Copyright (C) 2013 Corentin LABBE <clabbe.montjoie@gmail.com> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 * 14 * This program is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 * GNU General Public License for more details. 18 */ 19 20 /* 21 * The sun4i-ts controller is capable of detecting a second touch, but when a 22 * second touch is present then the accuracy becomes so bad the reported touch 23 * location is not useable. 24 * 25 * The original android driver contains some complicated heuristics using the 26 * aprox. distance between the 2 touches to see if the user is making a pinch 27 * open / close movement, and then reports emulated multi-touch events around 28 * the last touch coordinate (as the dual-touch coordinates are worthless). 29 * 30 * These kinds of heuristics are just asking for trouble (and don't belong 31 * in the kernel). So this driver offers straight forward, reliable single 32 * touch functionality only. 33 * 34 * s.a. A20 User Manual "1.15 TP" (Documentation/arm/sunxi/README) 35 * (looks like the description in the A20 User Manual v1.3 is better 36 * than the one in the A10 User Manual v.1.5) 37 */ 38 39 #include <linux/err.h> 40 #include <linux/hwmon.h> 41 #include <linux/thermal.h> 42 #include <linux/init.h> 43 #include <linux/input.h> 44 #include <linux/interrupt.h> 45 #include <linux/io.h> 46 #include <linux/module.h> 47 #include <linux/of_platform.h> 48 #include <linux/platform_device.h> 49 #include <linux/slab.h> 50 51 #define TP_CTRL0 0x00 52 #define TP_CTRL1 0x04 53 #define TP_CTRL2 0x08 54 #define TP_CTRL3 0x0c 55 #define TP_INT_FIFOC 0x10 56 #define TP_INT_FIFOS 0x14 57 #define TP_TPR 0x18 58 #define TP_CDAT 0x1c 59 #define TEMP_DATA 0x20 60 #define TP_DATA 0x24 61 62 /* TP_CTRL0 bits */ 63 #define ADC_FIRST_DLY(x) ((x) << 24) /* 8 bits */ 64 #define ADC_FIRST_DLY_MODE(x) ((x) << 23) 65 #define ADC_CLK_SEL(x) ((x) << 22) 66 #define ADC_CLK_DIV(x) ((x) << 20) /* 3 bits */ 67 #define FS_DIV(x) ((x) << 16) /* 4 bits */ 68 #define T_ACQ(x) ((x) << 0) /* 16 bits */ 69 70 /* TP_CTRL1 bits */ 71 #define STYLUS_UP_DEBOUN(x) ((x) << 12) /* 8 bits */ 72 #define STYLUS_UP_DEBOUN_EN(x) ((x) << 9) 73 #define TOUCH_PAN_CALI_EN(x) ((x) << 6) 74 #define TP_DUAL_EN(x) ((x) << 5) 75 #define TP_MODE_EN(x) ((x) << 4) 76 #define TP_ADC_SELECT(x) ((x) << 3) 77 #define ADC_CHAN_SELECT(x) ((x) << 0) /* 3 bits */ 78 79 /* on sun6i, bits 3~6 are left shifted by 1 to 4~7 */ 80 #define SUN6I_TP_MODE_EN(x) ((x) << 5) 81 82 /* TP_CTRL2 bits */ 83 #define TP_SENSITIVE_ADJUST(x) ((x) << 28) /* 4 bits */ 84 #define TP_MODE_SELECT(x) ((x) << 26) /* 2 bits */ 85 #define PRE_MEA_EN(x) ((x) << 24) 86 #define PRE_MEA_THRE_CNT(x) ((x) << 0) /* 24 bits */ 87 88 /* TP_CTRL3 bits */ 89 #define FILTER_EN(x) ((x) << 2) 90 #define FILTER_TYPE(x) ((x) << 0) /* 2 bits */ 91 92 /* TP_INT_FIFOC irq and fifo mask / control bits */ 93 #define TEMP_IRQ_EN(x) ((x) << 18) 94 #define OVERRUN_IRQ_EN(x) ((x) << 17) 95 #define DATA_IRQ_EN(x) ((x) << 16) 96 #define TP_DATA_XY_CHANGE(x) ((x) << 13) 97 #define FIFO_TRIG(x) ((x) << 8) /* 5 bits */ 98 #define DATA_DRQ_EN(x) ((x) << 7) 99 #define FIFO_FLUSH(x) ((x) << 4) 100 #define TP_UP_IRQ_EN(x) ((x) << 1) 101 #define TP_DOWN_IRQ_EN(x) ((x) << 0) 102 103 /* TP_INT_FIFOS irq and fifo status bits */ 104 #define TEMP_DATA_PENDING BIT(18) 105 #define FIFO_OVERRUN_PENDING BIT(17) 106 #define FIFO_DATA_PENDING BIT(16) 107 #define TP_IDLE_FLG BIT(2) 108 #define TP_UP_PENDING BIT(1) 109 #define TP_DOWN_PENDING BIT(0) 110 111 /* TP_TPR bits */ 112 #define TEMP_ENABLE(x) ((x) << 16) 113 #define TEMP_PERIOD(x) ((x) << 0) /* t = x * 256 * 16 / clkin */ 114 115 struct sun4i_ts_data { 116 struct device *dev; 117 struct input_dev *input; 118 struct thermal_zone_device *tz; 119 void __iomem *base; 120 unsigned int irq; 121 bool ignore_fifo_data; 122 int temp_data; 123 int temp_offset; 124 int temp_step; 125 }; 126 127 static void sun4i_ts_irq_handle_input(struct sun4i_ts_data *ts, u32 reg_val) 128 { 129 u32 x, y; 130 131 if (reg_val & FIFO_DATA_PENDING) { 132 x = readl(ts->base + TP_DATA); 133 y = readl(ts->base + TP_DATA); 134 /* The 1st location reported after an up event is unreliable */ 135 if (!ts->ignore_fifo_data) { 136 input_report_abs(ts->input, ABS_X, x); 137 input_report_abs(ts->input, ABS_Y, y); 138 /* 139 * The hardware has a separate down status bit, but 140 * that gets set before we get the first location, 141 * resulting in reporting a click on the old location. 142 */ 143 input_report_key(ts->input, BTN_TOUCH, 1); 144 input_sync(ts->input); 145 } else { 146 ts->ignore_fifo_data = false; 147 } 148 } 149 150 if (reg_val & TP_UP_PENDING) { 151 ts->ignore_fifo_data = true; 152 input_report_key(ts->input, BTN_TOUCH, 0); 153 input_sync(ts->input); 154 } 155 } 156 157 static irqreturn_t sun4i_ts_irq(int irq, void *dev_id) 158 { 159 struct sun4i_ts_data *ts = dev_id; 160 u32 reg_val; 161 162 reg_val = readl(ts->base + TP_INT_FIFOS); 163 164 if (reg_val & TEMP_DATA_PENDING) 165 ts->temp_data = readl(ts->base + TEMP_DATA); 166 167 if (ts->input) 168 sun4i_ts_irq_handle_input(ts, reg_val); 169 170 writel(reg_val, ts->base + TP_INT_FIFOS); 171 172 return IRQ_HANDLED; 173 } 174 175 static int sun4i_ts_open(struct input_dev *dev) 176 { 177 struct sun4i_ts_data *ts = input_get_drvdata(dev); 178 179 /* Flush, set trig level to 1, enable temp, data and up irqs */ 180 writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) | 181 TP_UP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 182 183 return 0; 184 } 185 186 static void sun4i_ts_close(struct input_dev *dev) 187 { 188 struct sun4i_ts_data *ts = input_get_drvdata(dev); 189 190 /* Deactivate all input IRQs */ 191 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 192 } 193 194 static int sun4i_get_temp(const struct sun4i_ts_data *ts, int *temp) 195 { 196 /* No temp_data until the first irq */ 197 if (ts->temp_data == -1) 198 return -EAGAIN; 199 200 *temp = ts->temp_data * ts->temp_step - ts->temp_offset; 201 202 return 0; 203 } 204 205 static int sun4i_get_tz_temp(void *data, int *temp) 206 { 207 return sun4i_get_temp(data, temp); 208 } 209 210 static struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { 211 .get_temp = sun4i_get_tz_temp, 212 }; 213 214 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 215 char *buf) 216 { 217 struct sun4i_ts_data *ts = dev_get_drvdata(dev); 218 int temp; 219 int error; 220 221 error = sun4i_get_temp(ts, &temp); 222 if (error) 223 return error; 224 225 return sprintf(buf, "%d\n", temp); 226 } 227 228 static ssize_t show_temp_label(struct device *dev, 229 struct device_attribute *devattr, char *buf) 230 { 231 return sprintf(buf, "SoC temperature\n"); 232 } 233 234 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL); 235 static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL); 236 237 static struct attribute *sun4i_ts_attrs[] = { 238 &dev_attr_temp1_input.attr, 239 &dev_attr_temp1_label.attr, 240 NULL 241 }; 242 ATTRIBUTE_GROUPS(sun4i_ts); 243 244 static int sun4i_ts_probe(struct platform_device *pdev) 245 { 246 struct sun4i_ts_data *ts; 247 struct device *dev = &pdev->dev; 248 struct device_node *np = dev->of_node; 249 struct device *hwmon; 250 int error; 251 u32 reg; 252 bool ts_attached; 253 u32 tp_sensitive_adjust = 15; 254 u32 filter_type = 1; 255 256 ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL); 257 if (!ts) 258 return -ENOMEM; 259 260 ts->dev = dev; 261 ts->ignore_fifo_data = true; 262 ts->temp_data = -1; 263 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) { 264 /* Allwinner SDK has temperature (C) = (value / 6) - 271 */ 265 ts->temp_offset = 271000; 266 ts->temp_step = 167; 267 } else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) { 268 /* 269 * The A10 temperature sensor has quite a wide spread, these 270 * parameters are based on the averaging of the calibration 271 * results of 4 completely different boards, with a spread of 272 * temp_step from 0.096 - 0.170 and temp_offset from 176 - 331. 273 */ 274 ts->temp_offset = 257000; 275 ts->temp_step = 133; 276 } else { 277 /* 278 * The user manuals do not contain the formula for calculating 279 * the temperature. The formula used here is from the AXP209, 280 * which is designed by X-Powers, an affiliate of Allwinner: 281 * 282 * temperature (C) = (value * 0.1) - 144.7 283 * 284 * Allwinner does not have any documentation whatsoever for 285 * this hardware. Moreover, it is claimed that the sensor 286 * is inaccurate and cannot work properly. 287 */ 288 ts->temp_offset = 144700; 289 ts->temp_step = 100; 290 } 291 292 ts_attached = of_property_read_bool(np, "allwinner,ts-attached"); 293 if (ts_attached) { 294 ts->input = devm_input_allocate_device(dev); 295 if (!ts->input) 296 return -ENOMEM; 297 298 ts->input->name = pdev->name; 299 ts->input->phys = "sun4i_ts/input0"; 300 ts->input->open = sun4i_ts_open; 301 ts->input->close = sun4i_ts_close; 302 ts->input->id.bustype = BUS_HOST; 303 ts->input->id.vendor = 0x0001; 304 ts->input->id.product = 0x0001; 305 ts->input->id.version = 0x0100; 306 ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS); 307 __set_bit(BTN_TOUCH, ts->input->keybit); 308 input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0); 309 input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0); 310 input_set_drvdata(ts->input, ts); 311 } 312 313 ts->base = devm_ioremap_resource(dev, 314 platform_get_resource(pdev, IORESOURCE_MEM, 0)); 315 if (IS_ERR(ts->base)) 316 return PTR_ERR(ts->base); 317 318 ts->irq = platform_get_irq(pdev, 0); 319 error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts); 320 if (error) 321 return error; 322 323 /* 324 * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192, 325 * t_acq = clkin / (16 * 64) 326 */ 327 writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63), 328 ts->base + TP_CTRL0); 329 330 /* 331 * tp_sensitive_adjust is an optional property 332 * tp_mode = 0 : only x and y coordinates, as we don't use dual touch 333 */ 334 of_property_read_u32(np, "allwinner,tp-sensitive-adjust", 335 &tp_sensitive_adjust); 336 writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0), 337 ts->base + TP_CTRL2); 338 339 /* 340 * Enable median and averaging filter, optional property for 341 * filter type. 342 */ 343 of_property_read_u32(np, "allwinner,filter-type", &filter_type); 344 writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3); 345 346 /* Enable temperature measurement, period 1953 (2 seconds) */ 347 writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR); 348 349 /* 350 * Set stylus up debounce to aprox 10 ms, enable debounce, and 351 * finally enable tp mode. 352 */ 353 reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1); 354 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) 355 reg |= SUN6I_TP_MODE_EN(1); 356 else 357 reg |= TP_MODE_EN(1); 358 writel(reg, ts->base + TP_CTRL1); 359 360 /* 361 * The thermal core does not register hwmon devices for DT-based 362 * thermal zone sensors, such as this one. 363 */ 364 hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts", 365 ts, sun4i_ts_groups); 366 if (IS_ERR(hwmon)) 367 return PTR_ERR(hwmon); 368 369 ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts, 370 &sun4i_ts_tz_ops); 371 if (IS_ERR(ts->tz)) 372 ts->tz = NULL; 373 374 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 375 376 if (ts_attached) { 377 error = input_register_device(ts->input); 378 if (error) { 379 writel(0, ts->base + TP_INT_FIFOC); 380 thermal_zone_of_sensor_unregister(ts->dev, ts->tz); 381 return error; 382 } 383 } 384 385 platform_set_drvdata(pdev, ts); 386 return 0; 387 } 388 389 static int sun4i_ts_remove(struct platform_device *pdev) 390 { 391 struct sun4i_ts_data *ts = platform_get_drvdata(pdev); 392 393 /* Explicit unregister to avoid open/close changing the imask later */ 394 if (ts->input) 395 input_unregister_device(ts->input); 396 397 thermal_zone_of_sensor_unregister(ts->dev, ts->tz); 398 399 /* Deactivate all IRQs */ 400 writel(0, ts->base + TP_INT_FIFOC); 401 402 return 0; 403 } 404 405 static const struct of_device_id sun4i_ts_of_match[] = { 406 { .compatible = "allwinner,sun4i-a10-ts", }, 407 { .compatible = "allwinner,sun5i-a13-ts", }, 408 { .compatible = "allwinner,sun6i-a31-ts", }, 409 { /* sentinel */ } 410 }; 411 MODULE_DEVICE_TABLE(of, sun4i_ts_of_match); 412 413 static struct platform_driver sun4i_ts_driver = { 414 .driver = { 415 .name = "sun4i-ts", 416 .of_match_table = of_match_ptr(sun4i_ts_of_match), 417 }, 418 .probe = sun4i_ts_probe, 419 .remove = sun4i_ts_remove, 420 }; 421 422 module_platform_driver(sun4i_ts_driver); 423 424 MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver"); 425 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 426 MODULE_LICENSE("GPL"); 427