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 void __iomem *base; 119 unsigned int irq; 120 bool ignore_fifo_data; 121 int temp_data; 122 int temp_offset; 123 int temp_step; 124 }; 125 126 static void sun4i_ts_irq_handle_input(struct sun4i_ts_data *ts, u32 reg_val) 127 { 128 u32 x, y; 129 130 if (reg_val & FIFO_DATA_PENDING) { 131 x = readl(ts->base + TP_DATA); 132 y = readl(ts->base + TP_DATA); 133 /* The 1st location reported after an up event is unreliable */ 134 if (!ts->ignore_fifo_data) { 135 input_report_abs(ts->input, ABS_X, x); 136 input_report_abs(ts->input, ABS_Y, y); 137 /* 138 * The hardware has a separate down status bit, but 139 * that gets set before we get the first location, 140 * resulting in reporting a click on the old location. 141 */ 142 input_report_key(ts->input, BTN_TOUCH, 1); 143 input_sync(ts->input); 144 } else { 145 ts->ignore_fifo_data = false; 146 } 147 } 148 149 if (reg_val & TP_UP_PENDING) { 150 ts->ignore_fifo_data = true; 151 input_report_key(ts->input, BTN_TOUCH, 0); 152 input_sync(ts->input); 153 } 154 } 155 156 static irqreturn_t sun4i_ts_irq(int irq, void *dev_id) 157 { 158 struct sun4i_ts_data *ts = dev_id; 159 u32 reg_val; 160 161 reg_val = readl(ts->base + TP_INT_FIFOS); 162 163 if (reg_val & TEMP_DATA_PENDING) 164 ts->temp_data = readl(ts->base + TEMP_DATA); 165 166 if (ts->input) 167 sun4i_ts_irq_handle_input(ts, reg_val); 168 169 writel(reg_val, ts->base + TP_INT_FIFOS); 170 171 return IRQ_HANDLED; 172 } 173 174 static int sun4i_ts_open(struct input_dev *dev) 175 { 176 struct sun4i_ts_data *ts = input_get_drvdata(dev); 177 178 /* Flush, set trig level to 1, enable temp, data and up irqs */ 179 writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) | 180 TP_UP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 181 182 return 0; 183 } 184 185 static void sun4i_ts_close(struct input_dev *dev) 186 { 187 struct sun4i_ts_data *ts = input_get_drvdata(dev); 188 189 /* Deactivate all input IRQs */ 190 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 191 } 192 193 static int sun4i_get_temp(const struct sun4i_ts_data *ts, int *temp) 194 { 195 /* No temp_data until the first irq */ 196 if (ts->temp_data == -1) 197 return -EAGAIN; 198 199 *temp = ts->temp_data * ts->temp_step - ts->temp_offset; 200 201 return 0; 202 } 203 204 static int sun4i_get_tz_temp(void *data, int *temp) 205 { 206 return sun4i_get_temp(data, temp); 207 } 208 209 static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { 210 .get_temp = sun4i_get_tz_temp, 211 }; 212 213 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 214 char *buf) 215 { 216 struct sun4i_ts_data *ts = dev_get_drvdata(dev); 217 int temp; 218 int error; 219 220 error = sun4i_get_temp(ts, &temp); 221 if (error) 222 return error; 223 224 return sprintf(buf, "%d\n", temp); 225 } 226 227 static ssize_t show_temp_label(struct device *dev, 228 struct device_attribute *devattr, char *buf) 229 { 230 return sprintf(buf, "SoC temperature\n"); 231 } 232 233 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL); 234 static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL); 235 236 static struct attribute *sun4i_ts_attrs[] = { 237 &dev_attr_temp1_input.attr, 238 &dev_attr_temp1_label.attr, 239 NULL 240 }; 241 ATTRIBUTE_GROUPS(sun4i_ts); 242 243 static int sun4i_ts_probe(struct platform_device *pdev) 244 { 245 struct sun4i_ts_data *ts; 246 struct device *dev = &pdev->dev; 247 struct device_node *np = dev->of_node; 248 struct device *hwmon; 249 int error; 250 u32 reg; 251 bool ts_attached; 252 u32 tp_sensitive_adjust = 15; 253 u32 filter_type = 1; 254 255 ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL); 256 if (!ts) 257 return -ENOMEM; 258 259 ts->dev = dev; 260 ts->ignore_fifo_data = true; 261 ts->temp_data = -1; 262 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) { 263 /* Allwinner SDK has temperature (C) = (value / 6) - 271 */ 264 ts->temp_offset = 271000; 265 ts->temp_step = 167; 266 } else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) { 267 /* 268 * The A10 temperature sensor has quite a wide spread, these 269 * parameters are based on the averaging of the calibration 270 * results of 4 completely different boards, with a spread of 271 * temp_step from 0.096 - 0.170 and temp_offset from 176 - 331. 272 */ 273 ts->temp_offset = 257000; 274 ts->temp_step = 133; 275 } else { 276 /* 277 * The user manuals do not contain the formula for calculating 278 * the temperature. The formula used here is from the AXP209, 279 * which is designed by X-Powers, an affiliate of Allwinner: 280 * 281 * temperature (C) = (value * 0.1) - 144.7 282 * 283 * Allwinner does not have any documentation whatsoever for 284 * this hardware. Moreover, it is claimed that the sensor 285 * is inaccurate and cannot work properly. 286 */ 287 ts->temp_offset = 144700; 288 ts->temp_step = 100; 289 } 290 291 ts_attached = of_property_read_bool(np, "allwinner,ts-attached"); 292 if (ts_attached) { 293 ts->input = devm_input_allocate_device(dev); 294 if (!ts->input) 295 return -ENOMEM; 296 297 ts->input->name = pdev->name; 298 ts->input->phys = "sun4i_ts/input0"; 299 ts->input->open = sun4i_ts_open; 300 ts->input->close = sun4i_ts_close; 301 ts->input->id.bustype = BUS_HOST; 302 ts->input->id.vendor = 0x0001; 303 ts->input->id.product = 0x0001; 304 ts->input->id.version = 0x0100; 305 ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS); 306 __set_bit(BTN_TOUCH, ts->input->keybit); 307 input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0); 308 input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0); 309 input_set_drvdata(ts->input, ts); 310 } 311 312 ts->base = devm_ioremap_resource(dev, 313 platform_get_resource(pdev, IORESOURCE_MEM, 0)); 314 if (IS_ERR(ts->base)) 315 return PTR_ERR(ts->base); 316 317 ts->irq = platform_get_irq(pdev, 0); 318 error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts); 319 if (error) 320 return error; 321 322 /* 323 * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192, 324 * t_acq = clkin / (16 * 64) 325 */ 326 writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63), 327 ts->base + TP_CTRL0); 328 329 /* 330 * tp_sensitive_adjust is an optional property 331 * tp_mode = 0 : only x and y coordinates, as we don't use dual touch 332 */ 333 of_property_read_u32(np, "allwinner,tp-sensitive-adjust", 334 &tp_sensitive_adjust); 335 writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0), 336 ts->base + TP_CTRL2); 337 338 /* 339 * Enable median and averaging filter, optional property for 340 * filter type. 341 */ 342 of_property_read_u32(np, "allwinner,filter-type", &filter_type); 343 writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3); 344 345 /* Enable temperature measurement, period 1953 (2 seconds) */ 346 writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR); 347 348 /* 349 * Set stylus up debounce to aprox 10 ms, enable debounce, and 350 * finally enable tp mode. 351 */ 352 reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1); 353 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) 354 reg |= SUN6I_TP_MODE_EN(1); 355 else 356 reg |= TP_MODE_EN(1); 357 writel(reg, ts->base + TP_CTRL1); 358 359 /* 360 * The thermal core does not register hwmon devices for DT-based 361 * thermal zone sensors, such as this one. 362 */ 363 hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts", 364 ts, sun4i_ts_groups); 365 if (IS_ERR(hwmon)) 366 return PTR_ERR(hwmon); 367 368 devm_thermal_zone_of_sensor_register(ts->dev, 0, ts, &sun4i_ts_tz_ops); 369 370 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 371 372 if (ts_attached) { 373 error = input_register_device(ts->input); 374 if (error) { 375 writel(0, ts->base + TP_INT_FIFOC); 376 return error; 377 } 378 } 379 380 platform_set_drvdata(pdev, ts); 381 return 0; 382 } 383 384 static int sun4i_ts_remove(struct platform_device *pdev) 385 { 386 struct sun4i_ts_data *ts = platform_get_drvdata(pdev); 387 388 /* Explicit unregister to avoid open/close changing the imask later */ 389 if (ts->input) 390 input_unregister_device(ts->input); 391 392 /* Deactivate all IRQs */ 393 writel(0, ts->base + TP_INT_FIFOC); 394 395 return 0; 396 } 397 398 static const struct of_device_id sun4i_ts_of_match[] = { 399 { .compatible = "allwinner,sun4i-a10-ts", }, 400 { .compatible = "allwinner,sun5i-a13-ts", }, 401 { .compatible = "allwinner,sun6i-a31-ts", }, 402 { /* sentinel */ } 403 }; 404 MODULE_DEVICE_TABLE(of, sun4i_ts_of_match); 405 406 static struct platform_driver sun4i_ts_driver = { 407 .driver = { 408 .name = "sun4i-ts", 409 .of_match_table = of_match_ptr(sun4i_ts_of_match), 410 }, 411 .probe = sun4i_ts_probe, 412 .remove = sun4i_ts_remove, 413 }; 414 415 module_platform_driver(sun4i_ts_driver); 416 417 MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver"); 418 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 419 MODULE_LICENSE("GPL"); 420