1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Allwinner sunxi resistive touchscreen controller driver 4 * 5 * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com> 6 * 7 * The hwmon parts are based on work by Corentin LABBE which is: 8 * Copyright (C) 2013 Corentin LABBE <clabbe.montjoie@gmail.com> 9 */ 10 11 /* 12 * The sun4i-ts controller is capable of detecting a second touch, but when a 13 * second touch is present then the accuracy becomes so bad the reported touch 14 * location is not useable. 15 * 16 * The original android driver contains some complicated heuristics using the 17 * aprox. distance between the 2 touches to see if the user is making a pinch 18 * open / close movement, and then reports emulated multi-touch events around 19 * the last touch coordinate (as the dual-touch coordinates are worthless). 20 * 21 * These kinds of heuristics are just asking for trouble (and don't belong 22 * in the kernel). So this driver offers straight forward, reliable single 23 * touch functionality only. 24 * 25 * s.a. A20 User Manual "1.15 TP" (Documentation/arm/sunxi.rst) 26 * (looks like the description in the A20 User Manual v1.3 is better 27 * than the one in the A10 User Manual v.1.5) 28 */ 29 30 #include <linux/err.h> 31 #include <linux/hwmon.h> 32 #include <linux/thermal.h> 33 #include <linux/init.h> 34 #include <linux/input.h> 35 #include <linux/interrupt.h> 36 #include <linux/io.h> 37 #include <linux/module.h> 38 #include <linux/of_platform.h> 39 #include <linux/platform_device.h> 40 #include <linux/slab.h> 41 42 #define TP_CTRL0 0x00 43 #define TP_CTRL1 0x04 44 #define TP_CTRL2 0x08 45 #define TP_CTRL3 0x0c 46 #define TP_INT_FIFOC 0x10 47 #define TP_INT_FIFOS 0x14 48 #define TP_TPR 0x18 49 #define TP_CDAT 0x1c 50 #define TEMP_DATA 0x20 51 #define TP_DATA 0x24 52 53 /* TP_CTRL0 bits */ 54 #define ADC_FIRST_DLY(x) ((x) << 24) /* 8 bits */ 55 #define ADC_FIRST_DLY_MODE(x) ((x) << 23) 56 #define ADC_CLK_SEL(x) ((x) << 22) 57 #define ADC_CLK_DIV(x) ((x) << 20) /* 3 bits */ 58 #define FS_DIV(x) ((x) << 16) /* 4 bits */ 59 #define T_ACQ(x) ((x) << 0) /* 16 bits */ 60 61 /* TP_CTRL1 bits */ 62 #define STYLUS_UP_DEBOUN(x) ((x) << 12) /* 8 bits */ 63 #define STYLUS_UP_DEBOUN_EN(x) ((x) << 9) 64 #define TOUCH_PAN_CALI_EN(x) ((x) << 6) 65 #define TP_DUAL_EN(x) ((x) << 5) 66 #define TP_MODE_EN(x) ((x) << 4) 67 #define TP_ADC_SELECT(x) ((x) << 3) 68 #define ADC_CHAN_SELECT(x) ((x) << 0) /* 3 bits */ 69 70 /* on sun6i, bits 3~6 are left shifted by 1 to 4~7 */ 71 #define SUN6I_TP_MODE_EN(x) ((x) << 5) 72 73 /* TP_CTRL2 bits */ 74 #define TP_SENSITIVE_ADJUST(x) ((x) << 28) /* 4 bits */ 75 #define TP_MODE_SELECT(x) ((x) << 26) /* 2 bits */ 76 #define PRE_MEA_EN(x) ((x) << 24) 77 #define PRE_MEA_THRE_CNT(x) ((x) << 0) /* 24 bits */ 78 79 /* TP_CTRL3 bits */ 80 #define FILTER_EN(x) ((x) << 2) 81 #define FILTER_TYPE(x) ((x) << 0) /* 2 bits */ 82 83 /* TP_INT_FIFOC irq and fifo mask / control bits */ 84 #define TEMP_IRQ_EN(x) ((x) << 18) 85 #define OVERRUN_IRQ_EN(x) ((x) << 17) 86 #define DATA_IRQ_EN(x) ((x) << 16) 87 #define TP_DATA_XY_CHANGE(x) ((x) << 13) 88 #define FIFO_TRIG(x) ((x) << 8) /* 5 bits */ 89 #define DATA_DRQ_EN(x) ((x) << 7) 90 #define FIFO_FLUSH(x) ((x) << 4) 91 #define TP_UP_IRQ_EN(x) ((x) << 1) 92 #define TP_DOWN_IRQ_EN(x) ((x) << 0) 93 94 /* TP_INT_FIFOS irq and fifo status bits */ 95 #define TEMP_DATA_PENDING BIT(18) 96 #define FIFO_OVERRUN_PENDING BIT(17) 97 #define FIFO_DATA_PENDING BIT(16) 98 #define TP_IDLE_FLG BIT(2) 99 #define TP_UP_PENDING BIT(1) 100 #define TP_DOWN_PENDING BIT(0) 101 102 /* TP_TPR bits */ 103 #define TEMP_ENABLE(x) ((x) << 16) 104 #define TEMP_PERIOD(x) ((x) << 0) /* t = x * 256 * 16 / clkin */ 105 106 struct sun4i_ts_data { 107 struct device *dev; 108 struct input_dev *input; 109 void __iomem *base; 110 unsigned int irq; 111 bool ignore_fifo_data; 112 int temp_data; 113 int temp_offset; 114 int temp_step; 115 }; 116 117 static void sun4i_ts_irq_handle_input(struct sun4i_ts_data *ts, u32 reg_val) 118 { 119 u32 x, y; 120 121 if (reg_val & FIFO_DATA_PENDING) { 122 x = readl(ts->base + TP_DATA); 123 y = readl(ts->base + TP_DATA); 124 /* The 1st location reported after an up event is unreliable */ 125 if (!ts->ignore_fifo_data) { 126 input_report_abs(ts->input, ABS_X, x); 127 input_report_abs(ts->input, ABS_Y, y); 128 /* 129 * The hardware has a separate down status bit, but 130 * that gets set before we get the first location, 131 * resulting in reporting a click on the old location. 132 */ 133 input_report_key(ts->input, BTN_TOUCH, 1); 134 input_sync(ts->input); 135 } else { 136 ts->ignore_fifo_data = false; 137 } 138 } 139 140 if (reg_val & TP_UP_PENDING) { 141 ts->ignore_fifo_data = true; 142 input_report_key(ts->input, BTN_TOUCH, 0); 143 input_sync(ts->input); 144 } 145 } 146 147 static irqreturn_t sun4i_ts_irq(int irq, void *dev_id) 148 { 149 struct sun4i_ts_data *ts = dev_id; 150 u32 reg_val; 151 152 reg_val = readl(ts->base + TP_INT_FIFOS); 153 154 if (reg_val & TEMP_DATA_PENDING) 155 ts->temp_data = readl(ts->base + TEMP_DATA); 156 157 if (ts->input) 158 sun4i_ts_irq_handle_input(ts, reg_val); 159 160 writel(reg_val, ts->base + TP_INT_FIFOS); 161 162 return IRQ_HANDLED; 163 } 164 165 static int sun4i_ts_open(struct input_dev *dev) 166 { 167 struct sun4i_ts_data *ts = input_get_drvdata(dev); 168 169 /* Flush, set trig level to 1, enable temp, data and up irqs */ 170 writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) | 171 TP_UP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 172 173 return 0; 174 } 175 176 static void sun4i_ts_close(struct input_dev *dev) 177 { 178 struct sun4i_ts_data *ts = input_get_drvdata(dev); 179 180 /* Deactivate all input IRQs */ 181 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 182 } 183 184 static int sun4i_get_temp(const struct sun4i_ts_data *ts, int *temp) 185 { 186 /* No temp_data until the first irq */ 187 if (ts->temp_data == -1) 188 return -EAGAIN; 189 190 *temp = ts->temp_data * ts->temp_step - ts->temp_offset; 191 192 return 0; 193 } 194 195 static int sun4i_get_tz_temp(void *data, int *temp) 196 { 197 return sun4i_get_temp(data, temp); 198 } 199 200 static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = { 201 .get_temp = sun4i_get_tz_temp, 202 }; 203 204 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr, 205 char *buf) 206 { 207 struct sun4i_ts_data *ts = dev_get_drvdata(dev); 208 int temp; 209 int error; 210 211 error = sun4i_get_temp(ts, &temp); 212 if (error) 213 return error; 214 215 return sprintf(buf, "%d\n", temp); 216 } 217 218 static ssize_t show_temp_label(struct device *dev, 219 struct device_attribute *devattr, char *buf) 220 { 221 return sprintf(buf, "SoC temperature\n"); 222 } 223 224 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL); 225 static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL); 226 227 static struct attribute *sun4i_ts_attrs[] = { 228 &dev_attr_temp1_input.attr, 229 &dev_attr_temp1_label.attr, 230 NULL 231 }; 232 ATTRIBUTE_GROUPS(sun4i_ts); 233 234 static int sun4i_ts_probe(struct platform_device *pdev) 235 { 236 struct sun4i_ts_data *ts; 237 struct device *dev = &pdev->dev; 238 struct device_node *np = dev->of_node; 239 struct device *hwmon; 240 struct thermal_zone_device *thermal; 241 int error; 242 u32 reg; 243 bool ts_attached; 244 u32 tp_sensitive_adjust = 15; 245 u32 filter_type = 1; 246 247 ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL); 248 if (!ts) 249 return -ENOMEM; 250 251 ts->dev = dev; 252 ts->ignore_fifo_data = true; 253 ts->temp_data = -1; 254 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) { 255 /* Allwinner SDK has temperature (C) = (value / 6) - 271 */ 256 ts->temp_offset = 271000; 257 ts->temp_step = 167; 258 } else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) { 259 /* 260 * The A10 temperature sensor has quite a wide spread, these 261 * parameters are based on the averaging of the calibration 262 * results of 4 completely different boards, with a spread of 263 * temp_step from 0.096 - 0.170 and temp_offset from 176 - 331. 264 */ 265 ts->temp_offset = 257000; 266 ts->temp_step = 133; 267 } else { 268 /* 269 * The user manuals do not contain the formula for calculating 270 * the temperature. The formula used here is from the AXP209, 271 * which is designed by X-Powers, an affiliate of Allwinner: 272 * 273 * temperature (C) = (value * 0.1) - 144.7 274 * 275 * Allwinner does not have any documentation whatsoever for 276 * this hardware. Moreover, it is claimed that the sensor 277 * is inaccurate and cannot work properly. 278 */ 279 ts->temp_offset = 144700; 280 ts->temp_step = 100; 281 } 282 283 ts_attached = of_property_read_bool(np, "allwinner,ts-attached"); 284 if (ts_attached) { 285 ts->input = devm_input_allocate_device(dev); 286 if (!ts->input) 287 return -ENOMEM; 288 289 ts->input->name = pdev->name; 290 ts->input->phys = "sun4i_ts/input0"; 291 ts->input->open = sun4i_ts_open; 292 ts->input->close = sun4i_ts_close; 293 ts->input->id.bustype = BUS_HOST; 294 ts->input->id.vendor = 0x0001; 295 ts->input->id.product = 0x0001; 296 ts->input->id.version = 0x0100; 297 ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS); 298 __set_bit(BTN_TOUCH, ts->input->keybit); 299 input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0); 300 input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0); 301 input_set_drvdata(ts->input, ts); 302 } 303 304 ts->base = devm_platform_ioremap_resource(pdev, 0); 305 if (IS_ERR(ts->base)) 306 return PTR_ERR(ts->base); 307 308 ts->irq = platform_get_irq(pdev, 0); 309 error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts); 310 if (error) 311 return error; 312 313 /* 314 * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192, 315 * t_acq = clkin / (16 * 64) 316 */ 317 writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63), 318 ts->base + TP_CTRL0); 319 320 /* 321 * tp_sensitive_adjust is an optional property 322 * tp_mode = 0 : only x and y coordinates, as we don't use dual touch 323 */ 324 of_property_read_u32(np, "allwinner,tp-sensitive-adjust", 325 &tp_sensitive_adjust); 326 writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0), 327 ts->base + TP_CTRL2); 328 329 /* 330 * Enable median and averaging filter, optional property for 331 * filter type. 332 */ 333 of_property_read_u32(np, "allwinner,filter-type", &filter_type); 334 writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3); 335 336 /* Enable temperature measurement, period 1953 (2 seconds) */ 337 writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR); 338 339 /* 340 * Set stylus up debounce to aprox 10 ms, enable debounce, and 341 * finally enable tp mode. 342 */ 343 reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1); 344 if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) 345 reg |= SUN6I_TP_MODE_EN(1); 346 else 347 reg |= TP_MODE_EN(1); 348 writel(reg, ts->base + TP_CTRL1); 349 350 /* 351 * The thermal core does not register hwmon devices for DT-based 352 * thermal zone sensors, such as this one. 353 */ 354 hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts", 355 ts, sun4i_ts_groups); 356 if (IS_ERR(hwmon)) 357 return PTR_ERR(hwmon); 358 359 thermal = devm_thermal_zone_of_sensor_register(ts->dev, 0, ts, 360 &sun4i_ts_tz_ops); 361 if (IS_ERR(thermal)) 362 return PTR_ERR(thermal); 363 364 writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC); 365 366 if (ts_attached) { 367 error = input_register_device(ts->input); 368 if (error) { 369 writel(0, ts->base + TP_INT_FIFOC); 370 return error; 371 } 372 } 373 374 platform_set_drvdata(pdev, ts); 375 return 0; 376 } 377 378 static int sun4i_ts_remove(struct platform_device *pdev) 379 { 380 struct sun4i_ts_data *ts = platform_get_drvdata(pdev); 381 382 /* Explicit unregister to avoid open/close changing the imask later */ 383 if (ts->input) 384 input_unregister_device(ts->input); 385 386 /* Deactivate all IRQs */ 387 writel(0, ts->base + TP_INT_FIFOC); 388 389 return 0; 390 } 391 392 static const struct of_device_id sun4i_ts_of_match[] = { 393 { .compatible = "allwinner,sun4i-a10-ts", }, 394 { .compatible = "allwinner,sun5i-a13-ts", }, 395 { .compatible = "allwinner,sun6i-a31-ts", }, 396 { /* sentinel */ } 397 }; 398 MODULE_DEVICE_TABLE(of, sun4i_ts_of_match); 399 400 static struct platform_driver sun4i_ts_driver = { 401 .driver = { 402 .name = "sun4i-ts", 403 .of_match_table = of_match_ptr(sun4i_ts_of_match), 404 }, 405 .probe = sun4i_ts_probe, 406 .remove = sun4i_ts_remove, 407 }; 408 409 module_platform_driver(sun4i_ts_driver); 410 411 MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver"); 412 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 413 MODULE_LICENSE("GPL"); 414