1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Driver for the ADC present in the Atmel AT91 evaluation boards. 4 * 5 * Copyright 2011 Free Electrons 6 */ 7 8 #include <linux/bitmap.h> 9 #include <linux/bitops.h> 10 #include <linux/clk.h> 11 #include <linux/err.h> 12 #include <linux/io.h> 13 #include <linux/input.h> 14 #include <linux/interrupt.h> 15 #include <linux/jiffies.h> 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/of_device.h> 20 #include <linux/platform_device.h> 21 #include <linux/sched.h> 22 #include <linux/slab.h> 23 #include <linux/wait.h> 24 25 #include <linux/platform_data/at91_adc.h> 26 27 #include <linux/iio/iio.h> 28 #include <linux/iio/buffer.h> 29 #include <linux/iio/trigger.h> 30 #include <linux/iio/trigger_consumer.h> 31 #include <linux/iio/triggered_buffer.h> 32 #include <linux/pinctrl/consumer.h> 33 34 /* Registers */ 35 #define AT91_ADC_CR 0x00 /* Control Register */ 36 #define AT91_ADC_SWRST (1 << 0) /* Software Reset */ 37 #define AT91_ADC_START (1 << 1) /* Start Conversion */ 38 39 #define AT91_ADC_MR 0x04 /* Mode Register */ 40 #define AT91_ADC_TSAMOD (3 << 0) /* ADC mode */ 41 #define AT91_ADC_TSAMOD_ADC_ONLY_MODE (0 << 0) /* ADC Mode */ 42 #define AT91_ADC_TSAMOD_TS_ONLY_MODE (1 << 0) /* Touch Screen Only Mode */ 43 #define AT91_ADC_TRGEN (1 << 0) /* Trigger Enable */ 44 #define AT91_ADC_TRGSEL (7 << 1) /* Trigger Selection */ 45 #define AT91_ADC_TRGSEL_TC0 (0 << 1) 46 #define AT91_ADC_TRGSEL_TC1 (1 << 1) 47 #define AT91_ADC_TRGSEL_TC2 (2 << 1) 48 #define AT91_ADC_TRGSEL_EXTERNAL (6 << 1) 49 #define AT91_ADC_LOWRES (1 << 4) /* Low Resolution */ 50 #define AT91_ADC_SLEEP (1 << 5) /* Sleep Mode */ 51 #define AT91_ADC_PENDET (1 << 6) /* Pen contact detection enable */ 52 #define AT91_ADC_PRESCAL_9260 (0x3f << 8) /* Prescalar Rate Selection */ 53 #define AT91_ADC_PRESCAL_9G45 (0xff << 8) 54 #define AT91_ADC_PRESCAL_(x) ((x) << 8) 55 #define AT91_ADC_STARTUP_9260 (0x1f << 16) /* Startup Up Time */ 56 #define AT91_ADC_STARTUP_9G45 (0x7f << 16) 57 #define AT91_ADC_STARTUP_9X5 (0xf << 16) 58 #define AT91_ADC_STARTUP_(x) ((x) << 16) 59 #define AT91_ADC_SHTIM (0xf << 24) /* Sample & Hold Time */ 60 #define AT91_ADC_SHTIM_(x) ((x) << 24) 61 #define AT91_ADC_PENDBC (0x0f << 28) /* Pen Debounce time */ 62 #define AT91_ADC_PENDBC_(x) ((x) << 28) 63 64 #define AT91_ADC_TSR 0x0C 65 #define AT91_ADC_TSR_SHTIM (0xf << 24) /* Sample & Hold Time */ 66 #define AT91_ADC_TSR_SHTIM_(x) ((x) << 24) 67 68 #define AT91_ADC_CHER 0x10 /* Channel Enable Register */ 69 #define AT91_ADC_CHDR 0x14 /* Channel Disable Register */ 70 #define AT91_ADC_CHSR 0x18 /* Channel Status Register */ 71 #define AT91_ADC_CH(n) (1 << (n)) /* Channel Number */ 72 73 #define AT91_ADC_SR 0x1C /* Status Register */ 74 #define AT91_ADC_EOC(n) (1 << (n)) /* End of Conversion on Channel N */ 75 #define AT91_ADC_OVRE(n) (1 << ((n) + 8))/* Overrun Error on Channel N */ 76 #define AT91_ADC_DRDY (1 << 16) /* Data Ready */ 77 #define AT91_ADC_GOVRE (1 << 17) /* General Overrun Error */ 78 #define AT91_ADC_ENDRX (1 << 18) /* End of RX Buffer */ 79 #define AT91_ADC_RXFUFF (1 << 19) /* RX Buffer Full */ 80 81 #define AT91_ADC_SR_9X5 0x30 /* Status Register for 9x5 */ 82 #define AT91_ADC_SR_DRDY_9X5 (1 << 24) /* Data Ready */ 83 84 #define AT91_ADC_LCDR 0x20 /* Last Converted Data Register */ 85 #define AT91_ADC_LDATA (0x3ff) 86 87 #define AT91_ADC_IER 0x24 /* Interrupt Enable Register */ 88 #define AT91_ADC_IDR 0x28 /* Interrupt Disable Register */ 89 #define AT91_ADC_IMR 0x2C /* Interrupt Mask Register */ 90 #define AT91RL_ADC_IER_PEN (1 << 20) 91 #define AT91RL_ADC_IER_NOPEN (1 << 21) 92 #define AT91_ADC_IER_PEN (1 << 29) 93 #define AT91_ADC_IER_NOPEN (1 << 30) 94 #define AT91_ADC_IER_XRDY (1 << 20) 95 #define AT91_ADC_IER_YRDY (1 << 21) 96 #define AT91_ADC_IER_PRDY (1 << 22) 97 #define AT91_ADC_ISR_PENS (1 << 31) 98 99 #define AT91_ADC_CHR(n) (0x30 + ((n) * 4)) /* Channel Data Register N */ 100 #define AT91_ADC_DATA (0x3ff) 101 102 #define AT91_ADC_CDR0_9X5 (0x50) /* Channel Data Register 0 for 9X5 */ 103 104 #define AT91_ADC_ACR 0x94 /* Analog Control Register */ 105 #define AT91_ADC_ACR_PENDETSENS (0x3 << 0) /* pull-up resistor */ 106 107 #define AT91_ADC_TSMR 0xB0 108 #define AT91_ADC_TSMR_TSMODE (3 << 0) /* Touch Screen Mode */ 109 #define AT91_ADC_TSMR_TSMODE_NONE (0 << 0) 110 #define AT91_ADC_TSMR_TSMODE_4WIRE_NO_PRESS (1 << 0) 111 #define AT91_ADC_TSMR_TSMODE_4WIRE_PRESS (2 << 0) 112 #define AT91_ADC_TSMR_TSMODE_5WIRE (3 << 0) 113 #define AT91_ADC_TSMR_TSAV (3 << 4) /* Averages samples */ 114 #define AT91_ADC_TSMR_TSAV_(x) ((x) << 4) 115 #define AT91_ADC_TSMR_SCTIM (0x0f << 16) /* Switch closure time */ 116 #define AT91_ADC_TSMR_SCTIM_(x) ((x) << 16) 117 #define AT91_ADC_TSMR_PENDBC (0x0f << 28) /* Pen Debounce time */ 118 #define AT91_ADC_TSMR_PENDBC_(x) ((x) << 28) 119 #define AT91_ADC_TSMR_NOTSDMA (1 << 22) /* No Touchscreen DMA */ 120 #define AT91_ADC_TSMR_PENDET_DIS (0 << 24) /* Pen contact detection disable */ 121 #define AT91_ADC_TSMR_PENDET_ENA (1 << 24) /* Pen contact detection enable */ 122 123 #define AT91_ADC_TSXPOSR 0xB4 124 #define AT91_ADC_TSYPOSR 0xB8 125 #define AT91_ADC_TSPRESSR 0xBC 126 127 #define AT91_ADC_TRGR_9260 AT91_ADC_MR 128 #define AT91_ADC_TRGR_9G45 0x08 129 #define AT91_ADC_TRGR_9X5 0xC0 130 131 /* Trigger Register bit field */ 132 #define AT91_ADC_TRGR_TRGPER (0xffff << 16) 133 #define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16) 134 #define AT91_ADC_TRGR_TRGMOD (0x7 << 0) 135 #define AT91_ADC_TRGR_NONE (0 << 0) 136 #define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0) 137 138 #define AT91_ADC_CHAN(st, ch) \ 139 (st->registers->channel_base + (ch * 4)) 140 #define at91_adc_readl(st, reg) \ 141 (readl_relaxed(st->reg_base + reg)) 142 #define at91_adc_writel(st, reg, val) \ 143 (writel_relaxed(val, st->reg_base + reg)) 144 145 #define DRIVER_NAME "at91_adc" 146 #define MAX_POS_BITS 12 147 148 #define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */ 149 #define TOUCH_PEN_DETECT_DEBOUNCE_US 200 150 151 #define MAX_RLPOS_BITS 10 152 #define TOUCH_SAMPLE_PERIOD_US_RL 10000 /* 10ms, the SoC can't keep up with 2ms */ 153 #define TOUCH_SHTIM 0xa 154 #define TOUCH_SCTIM_US 10 /* 10us for the Touchscreen Switches Closure Time */ 155 156 /** 157 * struct at91_adc_reg_desc - Various informations relative to registers 158 * @channel_base: Base offset for the channel data registers 159 * @drdy_mask: Mask of the DRDY field in the relevant registers 160 (Interruptions registers mostly) 161 * @status_register: Offset of the Interrupt Status Register 162 * @trigger_register: Offset of the Trigger setup register 163 * @mr_prescal_mask: Mask of the PRESCAL field in the adc MR register 164 * @mr_startup_mask: Mask of the STARTUP field in the adc MR register 165 */ 166 struct at91_adc_reg_desc { 167 u8 channel_base; 168 u32 drdy_mask; 169 u8 status_register; 170 u8 trigger_register; 171 u32 mr_prescal_mask; 172 u32 mr_startup_mask; 173 }; 174 175 struct at91_adc_caps { 176 bool has_ts; /* Support touch screen */ 177 bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */ 178 /* 179 * Numbers of sampling data will be averaged. Can be 0~3. 180 * Hardware can average (2 ^ ts_filter_average) sample data. 181 */ 182 u8 ts_filter_average; 183 /* Pen Detection input pull-up resistor, can be 0~3 */ 184 u8 ts_pen_detect_sensitivity; 185 186 /* startup time calculate function */ 187 u32 (*calc_startup_ticks)(u32 startup_time, u32 adc_clk_khz); 188 189 u8 num_channels; 190 struct at91_adc_reg_desc registers; 191 }; 192 193 struct at91_adc_state { 194 struct clk *adc_clk; 195 u16 *buffer; 196 unsigned long channels_mask; 197 struct clk *clk; 198 bool done; 199 int irq; 200 u16 last_value; 201 int chnb; 202 struct mutex lock; 203 u8 num_channels; 204 void __iomem *reg_base; 205 struct at91_adc_reg_desc *registers; 206 u32 startup_time; 207 u8 sample_hold_time; 208 bool sleep_mode; 209 struct iio_trigger **trig; 210 struct at91_adc_trigger *trigger_list; 211 u32 trigger_number; 212 bool use_external; 213 u32 vref_mv; 214 u32 res; /* resolution used for convertions */ 215 bool low_res; /* the resolution corresponds to the lowest one */ 216 wait_queue_head_t wq_data_avail; 217 struct at91_adc_caps *caps; 218 219 /* 220 * Following ADC channels are shared by touchscreen: 221 * 222 * CH0 -- Touch screen XP/UL 223 * CH1 -- Touch screen XM/UR 224 * CH2 -- Touch screen YP/LL 225 * CH3 -- Touch screen YM/Sense 226 * CH4 -- Touch screen LR(5-wire only) 227 * 228 * The bitfields below represents the reserved channel in the 229 * touchscreen mode. 230 */ 231 #define CHAN_MASK_TOUCHSCREEN_4WIRE (0xf << 0) 232 #define CHAN_MASK_TOUCHSCREEN_5WIRE (0x1f << 0) 233 enum atmel_adc_ts_type touchscreen_type; 234 struct input_dev *ts_input; 235 236 u16 ts_sample_period_val; 237 u32 ts_pressure_threshold; 238 u16 ts_pendbc; 239 240 bool ts_bufferedmeasure; 241 u32 ts_prev_absx; 242 u32 ts_prev_absy; 243 }; 244 245 static irqreturn_t at91_adc_trigger_handler(int irq, void *p) 246 { 247 struct iio_poll_func *pf = p; 248 struct iio_dev *idev = pf->indio_dev; 249 struct at91_adc_state *st = iio_priv(idev); 250 struct iio_chan_spec const *chan; 251 int i, j = 0; 252 253 for (i = 0; i < idev->masklength; i++) { 254 if (!test_bit(i, idev->active_scan_mask)) 255 continue; 256 chan = idev->channels + i; 257 st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, chan->channel)); 258 j++; 259 } 260 261 iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp); 262 263 iio_trigger_notify_done(idev->trig); 264 265 /* Needed to ACK the DRDY interruption */ 266 at91_adc_readl(st, AT91_ADC_LCDR); 267 268 enable_irq(st->irq); 269 270 return IRQ_HANDLED; 271 } 272 273 /* Handler for classic adc channel eoc trigger */ 274 static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev) 275 { 276 struct at91_adc_state *st = iio_priv(idev); 277 278 if (iio_buffer_enabled(idev)) { 279 disable_irq_nosync(irq); 280 iio_trigger_poll(idev->trig); 281 } else { 282 st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb)); 283 /* Needed to ACK the DRDY interruption */ 284 at91_adc_readl(st, AT91_ADC_LCDR); 285 st->done = true; 286 wake_up_interruptible(&st->wq_data_avail); 287 } 288 } 289 290 static int at91_ts_sample(struct at91_adc_state *st) 291 { 292 unsigned int xscale, yscale, reg, z1, z2; 293 unsigned int x, y, pres, xpos, ypos; 294 unsigned int rxp = 1; 295 unsigned int factor = 1000; 296 struct iio_dev *idev = iio_priv_to_dev(st); 297 298 unsigned int xyz_mask_bits = st->res; 299 unsigned int xyz_mask = (1 << xyz_mask_bits) - 1; 300 301 /* calculate position */ 302 /* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */ 303 reg = at91_adc_readl(st, AT91_ADC_TSXPOSR); 304 xpos = reg & xyz_mask; 305 x = (xpos << MAX_POS_BITS) - xpos; 306 xscale = (reg >> 16) & xyz_mask; 307 if (xscale == 0) { 308 dev_err(&idev->dev, "Error: xscale == 0!\n"); 309 return -1; 310 } 311 x /= xscale; 312 313 /* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */ 314 reg = at91_adc_readl(st, AT91_ADC_TSYPOSR); 315 ypos = reg & xyz_mask; 316 y = (ypos << MAX_POS_BITS) - ypos; 317 yscale = (reg >> 16) & xyz_mask; 318 if (yscale == 0) { 319 dev_err(&idev->dev, "Error: yscale == 0!\n"); 320 return -1; 321 } 322 y /= yscale; 323 324 /* calculate the pressure */ 325 reg = at91_adc_readl(st, AT91_ADC_TSPRESSR); 326 z1 = reg & xyz_mask; 327 z2 = (reg >> 16) & xyz_mask; 328 329 if (z1 != 0) 330 pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor) 331 / factor; 332 else 333 pres = st->ts_pressure_threshold; /* no pen contacted */ 334 335 dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n", 336 xpos, xscale, ypos, yscale, z1, z2, pres); 337 338 if (pres < st->ts_pressure_threshold) { 339 dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n", 340 x, y, pres / factor); 341 input_report_abs(st->ts_input, ABS_X, x); 342 input_report_abs(st->ts_input, ABS_Y, y); 343 input_report_abs(st->ts_input, ABS_PRESSURE, pres); 344 input_report_key(st->ts_input, BTN_TOUCH, 1); 345 input_sync(st->ts_input); 346 } else { 347 dev_dbg(&idev->dev, "pressure too low: not reporting\n"); 348 } 349 350 return 0; 351 } 352 353 static irqreturn_t at91_adc_rl_interrupt(int irq, void *private) 354 { 355 struct iio_dev *idev = private; 356 struct at91_adc_state *st = iio_priv(idev); 357 u32 status = at91_adc_readl(st, st->registers->status_register); 358 unsigned int reg; 359 360 status &= at91_adc_readl(st, AT91_ADC_IMR); 361 if (status & GENMASK(st->num_channels - 1, 0)) 362 handle_adc_eoc_trigger(irq, idev); 363 364 if (status & AT91RL_ADC_IER_PEN) { 365 /* Disabling pen debounce is required to get a NOPEN irq */ 366 reg = at91_adc_readl(st, AT91_ADC_MR); 367 reg &= ~AT91_ADC_PENDBC; 368 at91_adc_writel(st, AT91_ADC_MR, reg); 369 370 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN); 371 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN 372 | AT91_ADC_EOC(3)); 373 /* Set up period trigger for sampling */ 374 at91_adc_writel(st, st->registers->trigger_register, 375 AT91_ADC_TRGR_MOD_PERIOD_TRIG | 376 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val)); 377 } else if (status & AT91RL_ADC_IER_NOPEN) { 378 reg = at91_adc_readl(st, AT91_ADC_MR); 379 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC; 380 at91_adc_writel(st, AT91_ADC_MR, reg); 381 at91_adc_writel(st, st->registers->trigger_register, 382 AT91_ADC_TRGR_NONE); 383 384 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN 385 | AT91_ADC_EOC(3)); 386 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN); 387 st->ts_bufferedmeasure = false; 388 input_report_key(st->ts_input, BTN_TOUCH, 0); 389 input_sync(st->ts_input); 390 } else if (status & AT91_ADC_EOC(3) && st->ts_input) { 391 /* Conversion finished and we've a touchscreen */ 392 if (st->ts_bufferedmeasure) { 393 /* 394 * Last measurement is always discarded, since it can 395 * be erroneous. 396 * Always report previous measurement 397 */ 398 input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx); 399 input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy); 400 input_report_key(st->ts_input, BTN_TOUCH, 1); 401 input_sync(st->ts_input); 402 } else 403 st->ts_bufferedmeasure = true; 404 405 /* Now make new measurement */ 406 st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3)) 407 << MAX_RLPOS_BITS; 408 st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2)); 409 410 st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1)) 411 << MAX_RLPOS_BITS; 412 st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0)); 413 } 414 415 return IRQ_HANDLED; 416 } 417 418 static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private) 419 { 420 struct iio_dev *idev = private; 421 struct at91_adc_state *st = iio_priv(idev); 422 u32 status = at91_adc_readl(st, st->registers->status_register); 423 const uint32_t ts_data_irq_mask = 424 AT91_ADC_IER_XRDY | 425 AT91_ADC_IER_YRDY | 426 AT91_ADC_IER_PRDY; 427 428 if (status & GENMASK(st->num_channels - 1, 0)) 429 handle_adc_eoc_trigger(irq, idev); 430 431 if (status & AT91_ADC_IER_PEN) { 432 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN); 433 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN | 434 ts_data_irq_mask); 435 /* Set up period trigger for sampling */ 436 at91_adc_writel(st, st->registers->trigger_register, 437 AT91_ADC_TRGR_MOD_PERIOD_TRIG | 438 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val)); 439 } else if (status & AT91_ADC_IER_NOPEN) { 440 at91_adc_writel(st, st->registers->trigger_register, 0); 441 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN | 442 ts_data_irq_mask); 443 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN); 444 445 input_report_key(st->ts_input, BTN_TOUCH, 0); 446 input_sync(st->ts_input); 447 } else if ((status & ts_data_irq_mask) == ts_data_irq_mask) { 448 /* Now all touchscreen data is ready */ 449 450 if (status & AT91_ADC_ISR_PENS) { 451 /* validate data by pen contact */ 452 at91_ts_sample(st); 453 } else { 454 /* triggered by event that is no pen contact, just read 455 * them to clean the interrupt and discard all. 456 */ 457 at91_adc_readl(st, AT91_ADC_TSXPOSR); 458 at91_adc_readl(st, AT91_ADC_TSYPOSR); 459 at91_adc_readl(st, AT91_ADC_TSPRESSR); 460 } 461 } 462 463 return IRQ_HANDLED; 464 } 465 466 static int at91_adc_channel_init(struct iio_dev *idev) 467 { 468 struct at91_adc_state *st = iio_priv(idev); 469 struct iio_chan_spec *chan_array, *timestamp; 470 int bit, idx = 0; 471 unsigned long rsvd_mask = 0; 472 473 /* If touchscreen is enable, then reserve the adc channels */ 474 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE) 475 rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE; 476 else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE) 477 rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE; 478 479 /* set up the channel mask to reserve touchscreen channels */ 480 st->channels_mask &= ~rsvd_mask; 481 482 idev->num_channels = bitmap_weight(&st->channels_mask, 483 st->num_channels) + 1; 484 485 chan_array = devm_kzalloc(&idev->dev, 486 ((idev->num_channels + 1) * 487 sizeof(struct iio_chan_spec)), 488 GFP_KERNEL); 489 490 if (!chan_array) 491 return -ENOMEM; 492 493 for_each_set_bit(bit, &st->channels_mask, st->num_channels) { 494 struct iio_chan_spec *chan = chan_array + idx; 495 496 chan->type = IIO_VOLTAGE; 497 chan->indexed = 1; 498 chan->channel = bit; 499 chan->scan_index = idx; 500 chan->scan_type.sign = 'u'; 501 chan->scan_type.realbits = st->res; 502 chan->scan_type.storagebits = 16; 503 chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE); 504 chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); 505 idx++; 506 } 507 timestamp = chan_array + idx; 508 509 timestamp->type = IIO_TIMESTAMP; 510 timestamp->channel = -1; 511 timestamp->scan_index = idx; 512 timestamp->scan_type.sign = 's'; 513 timestamp->scan_type.realbits = 64; 514 timestamp->scan_type.storagebits = 64; 515 516 idev->channels = chan_array; 517 return idev->num_channels; 518 } 519 520 static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev, 521 struct at91_adc_trigger *triggers, 522 const char *trigger_name) 523 { 524 struct at91_adc_state *st = iio_priv(idev); 525 int i; 526 527 for (i = 0; i < st->trigger_number; i++) { 528 char *name = kasprintf(GFP_KERNEL, 529 "%s-dev%d-%s", 530 idev->name, 531 idev->id, 532 triggers[i].name); 533 if (!name) 534 return -ENOMEM; 535 536 if (strcmp(trigger_name, name) == 0) { 537 kfree(name); 538 if (triggers[i].value == 0) 539 return -EINVAL; 540 return triggers[i].value; 541 } 542 543 kfree(name); 544 } 545 546 return -EINVAL; 547 } 548 549 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) 550 { 551 struct iio_dev *idev = iio_trigger_get_drvdata(trig); 552 struct at91_adc_state *st = iio_priv(idev); 553 struct at91_adc_reg_desc *reg = st->registers; 554 u32 status = at91_adc_readl(st, reg->trigger_register); 555 int value; 556 u8 bit; 557 558 value = at91_adc_get_trigger_value_by_name(idev, 559 st->trigger_list, 560 idev->trig->name); 561 if (value < 0) 562 return value; 563 564 if (state) { 565 st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL); 566 if (st->buffer == NULL) 567 return -ENOMEM; 568 569 at91_adc_writel(st, reg->trigger_register, 570 status | value); 571 572 for_each_set_bit(bit, idev->active_scan_mask, 573 st->num_channels) { 574 struct iio_chan_spec const *chan = idev->channels + bit; 575 at91_adc_writel(st, AT91_ADC_CHER, 576 AT91_ADC_CH(chan->channel)); 577 } 578 579 at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask); 580 581 } else { 582 at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask); 583 584 at91_adc_writel(st, reg->trigger_register, 585 status & ~value); 586 587 for_each_set_bit(bit, idev->active_scan_mask, 588 st->num_channels) { 589 struct iio_chan_spec const *chan = idev->channels + bit; 590 at91_adc_writel(st, AT91_ADC_CHDR, 591 AT91_ADC_CH(chan->channel)); 592 } 593 kfree(st->buffer); 594 } 595 596 return 0; 597 } 598 599 static const struct iio_trigger_ops at91_adc_trigger_ops = { 600 .set_trigger_state = &at91_adc_configure_trigger, 601 }; 602 603 static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev, 604 struct at91_adc_trigger *trigger) 605 { 606 struct iio_trigger *trig; 607 int ret; 608 609 trig = iio_trigger_alloc("%s-dev%d-%s", idev->name, 610 idev->id, trigger->name); 611 if (trig == NULL) 612 return NULL; 613 614 trig->dev.parent = idev->dev.parent; 615 iio_trigger_set_drvdata(trig, idev); 616 trig->ops = &at91_adc_trigger_ops; 617 618 ret = iio_trigger_register(trig); 619 if (ret) 620 return NULL; 621 622 return trig; 623 } 624 625 static int at91_adc_trigger_init(struct iio_dev *idev) 626 { 627 struct at91_adc_state *st = iio_priv(idev); 628 int i, ret; 629 630 st->trig = devm_kcalloc(&idev->dev, 631 st->trigger_number, sizeof(*st->trig), 632 GFP_KERNEL); 633 634 if (st->trig == NULL) { 635 ret = -ENOMEM; 636 goto error_ret; 637 } 638 639 for (i = 0; i < st->trigger_number; i++) { 640 if (st->trigger_list[i].is_external && !(st->use_external)) 641 continue; 642 643 st->trig[i] = at91_adc_allocate_trigger(idev, 644 st->trigger_list + i); 645 if (st->trig[i] == NULL) { 646 dev_err(&idev->dev, 647 "Could not allocate trigger %d\n", i); 648 ret = -ENOMEM; 649 goto error_trigger; 650 } 651 } 652 653 return 0; 654 655 error_trigger: 656 for (i--; i >= 0; i--) { 657 iio_trigger_unregister(st->trig[i]); 658 iio_trigger_free(st->trig[i]); 659 } 660 error_ret: 661 return ret; 662 } 663 664 static void at91_adc_trigger_remove(struct iio_dev *idev) 665 { 666 struct at91_adc_state *st = iio_priv(idev); 667 int i; 668 669 for (i = 0; i < st->trigger_number; i++) { 670 iio_trigger_unregister(st->trig[i]); 671 iio_trigger_free(st->trig[i]); 672 } 673 } 674 675 static int at91_adc_buffer_init(struct iio_dev *idev) 676 { 677 return iio_triggered_buffer_setup(idev, &iio_pollfunc_store_time, 678 &at91_adc_trigger_handler, NULL); 679 } 680 681 static void at91_adc_buffer_remove(struct iio_dev *idev) 682 { 683 iio_triggered_buffer_cleanup(idev); 684 } 685 686 static int at91_adc_read_raw(struct iio_dev *idev, 687 struct iio_chan_spec const *chan, 688 int *val, int *val2, long mask) 689 { 690 struct at91_adc_state *st = iio_priv(idev); 691 int ret; 692 693 switch (mask) { 694 case IIO_CHAN_INFO_RAW: 695 mutex_lock(&st->lock); 696 697 st->chnb = chan->channel; 698 at91_adc_writel(st, AT91_ADC_CHER, 699 AT91_ADC_CH(chan->channel)); 700 at91_adc_writel(st, AT91_ADC_IER, BIT(chan->channel)); 701 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START); 702 703 ret = wait_event_interruptible_timeout(st->wq_data_avail, 704 st->done, 705 msecs_to_jiffies(1000)); 706 707 /* Disable interrupts, regardless if adc conversion was 708 * successful or not 709 */ 710 at91_adc_writel(st, AT91_ADC_CHDR, 711 AT91_ADC_CH(chan->channel)); 712 at91_adc_writel(st, AT91_ADC_IDR, BIT(chan->channel)); 713 714 if (ret > 0) { 715 /* a valid conversion took place */ 716 *val = st->last_value; 717 st->last_value = 0; 718 st->done = false; 719 ret = IIO_VAL_INT; 720 } else if (ret == 0) { 721 /* conversion timeout */ 722 dev_err(&idev->dev, "ADC Channel %d timeout.\n", 723 chan->channel); 724 ret = -ETIMEDOUT; 725 } 726 727 mutex_unlock(&st->lock); 728 return ret; 729 730 case IIO_CHAN_INFO_SCALE: 731 *val = st->vref_mv; 732 *val2 = chan->scan_type.realbits; 733 return IIO_VAL_FRACTIONAL_LOG2; 734 default: 735 break; 736 } 737 return -EINVAL; 738 } 739 740 static int at91_adc_of_get_resolution(struct at91_adc_state *st, 741 struct platform_device *pdev) 742 { 743 struct iio_dev *idev = iio_priv_to_dev(st); 744 struct device_node *np = pdev->dev.of_node; 745 int count, i, ret = 0; 746 char *res_name, *s; 747 u32 *resolutions; 748 749 count = of_property_count_strings(np, "atmel,adc-res-names"); 750 if (count < 2) { 751 dev_err(&idev->dev, "You must specified at least two resolution names for " 752 "adc-res-names property in the DT\n"); 753 return count; 754 } 755 756 resolutions = kmalloc_array(count, sizeof(*resolutions), GFP_KERNEL); 757 if (!resolutions) 758 return -ENOMEM; 759 760 if (of_property_read_u32_array(np, "atmel,adc-res", resolutions, count)) { 761 dev_err(&idev->dev, "Missing adc-res property in the DT.\n"); 762 ret = -ENODEV; 763 goto ret; 764 } 765 766 if (of_property_read_string(np, "atmel,adc-use-res", (const char **)&res_name)) 767 res_name = "highres"; 768 769 for (i = 0; i < count; i++) { 770 if (of_property_read_string_index(np, "atmel,adc-res-names", i, (const char **)&s)) 771 continue; 772 773 if (strcmp(res_name, s)) 774 continue; 775 776 st->res = resolutions[i]; 777 if (!strcmp(res_name, "lowres")) 778 st->low_res = true; 779 else 780 st->low_res = false; 781 782 dev_info(&idev->dev, "Resolution used: %u bits\n", st->res); 783 goto ret; 784 } 785 786 dev_err(&idev->dev, "There is no resolution for %s\n", res_name); 787 788 ret: 789 kfree(resolutions); 790 return ret; 791 } 792 793 static u32 calc_startup_ticks_9260(u32 startup_time, u32 adc_clk_khz) 794 { 795 /* 796 * Number of ticks needed to cover the startup time of the ADC 797 * as defined in the electrical characteristics of the board, 798 * divided by 8. The formula thus is : 799 * Startup Time = (ticks + 1) * 8 / ADC Clock 800 */ 801 return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8; 802 } 803 804 static u32 calc_startup_ticks_9x5(u32 startup_time, u32 adc_clk_khz) 805 { 806 /* 807 * For sama5d3x and at91sam9x5, the formula changes to: 808 * Startup Time = <lookup_table_value> / ADC Clock 809 */ 810 static const int startup_lookup[] = { 811 0, 8, 16, 24, 812 64, 80, 96, 112, 813 512, 576, 640, 704, 814 768, 832, 896, 960 815 }; 816 int i, size = ARRAY_SIZE(startup_lookup); 817 unsigned int ticks; 818 819 ticks = startup_time * adc_clk_khz / 1000; 820 for (i = 0; i < size; i++) 821 if (ticks < startup_lookup[i]) 822 break; 823 824 ticks = i; 825 if (ticks == size) 826 /* Reach the end of lookup table */ 827 ticks = size - 1; 828 829 return ticks; 830 } 831 832 static const struct of_device_id at91_adc_dt_ids[]; 833 834 static int at91_adc_probe_dt_ts(struct device_node *node, 835 struct at91_adc_state *st, struct device *dev) 836 { 837 int ret; 838 u32 prop; 839 840 ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop); 841 if (ret) { 842 dev_info(dev, "ADC Touch screen is disabled.\n"); 843 return 0; 844 } 845 846 switch (prop) { 847 case 4: 848 case 5: 849 st->touchscreen_type = prop; 850 break; 851 default: 852 dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop); 853 return -EINVAL; 854 } 855 856 if (!st->caps->has_tsmr) 857 return 0; 858 prop = 0; 859 of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop); 860 st->ts_pressure_threshold = prop; 861 if (st->ts_pressure_threshold) { 862 return 0; 863 } else { 864 dev_err(dev, "Invalid pressure threshold for the touchscreen\n"); 865 return -EINVAL; 866 } 867 } 868 869 static int at91_adc_probe_dt(struct at91_adc_state *st, 870 struct platform_device *pdev) 871 { 872 struct iio_dev *idev = iio_priv_to_dev(st); 873 struct device_node *node = pdev->dev.of_node; 874 struct device_node *trig_node; 875 int i = 0, ret; 876 u32 prop; 877 878 if (!node) 879 return -EINVAL; 880 881 st->caps = (struct at91_adc_caps *) 882 of_match_device(at91_adc_dt_ids, &pdev->dev)->data; 883 884 st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers"); 885 886 if (of_property_read_u32(node, "atmel,adc-channels-used", &prop)) { 887 dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n"); 888 ret = -EINVAL; 889 goto error_ret; 890 } 891 st->channels_mask = prop; 892 893 st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode"); 894 895 if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) { 896 dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n"); 897 ret = -EINVAL; 898 goto error_ret; 899 } 900 st->startup_time = prop; 901 902 prop = 0; 903 of_property_read_u32(node, "atmel,adc-sample-hold-time", &prop); 904 st->sample_hold_time = prop; 905 906 if (of_property_read_u32(node, "atmel,adc-vref", &prop)) { 907 dev_err(&idev->dev, "Missing adc-vref property in the DT.\n"); 908 ret = -EINVAL; 909 goto error_ret; 910 } 911 st->vref_mv = prop; 912 913 ret = at91_adc_of_get_resolution(st, pdev); 914 if (ret) 915 goto error_ret; 916 917 st->registers = &st->caps->registers; 918 st->num_channels = st->caps->num_channels; 919 st->trigger_number = of_get_child_count(node); 920 st->trigger_list = devm_kcalloc(&idev->dev, 921 st->trigger_number, 922 sizeof(struct at91_adc_trigger), 923 GFP_KERNEL); 924 if (!st->trigger_list) { 925 dev_err(&idev->dev, "Could not allocate trigger list memory.\n"); 926 ret = -ENOMEM; 927 goto error_ret; 928 } 929 930 for_each_child_of_node(node, trig_node) { 931 struct at91_adc_trigger *trig = st->trigger_list + i; 932 const char *name; 933 934 if (of_property_read_string(trig_node, "trigger-name", &name)) { 935 dev_err(&idev->dev, "Missing trigger-name property in the DT.\n"); 936 ret = -EINVAL; 937 goto error_ret; 938 } 939 trig->name = name; 940 941 if (of_property_read_u32(trig_node, "trigger-value", &prop)) { 942 dev_err(&idev->dev, "Missing trigger-value property in the DT.\n"); 943 ret = -EINVAL; 944 goto error_ret; 945 } 946 trig->value = prop; 947 trig->is_external = of_property_read_bool(trig_node, "trigger-external"); 948 i++; 949 } 950 951 /* Check if touchscreen is supported. */ 952 if (st->caps->has_ts) 953 return at91_adc_probe_dt_ts(node, st, &idev->dev); 954 else 955 dev_info(&idev->dev, "not support touchscreen in the adc compatible string.\n"); 956 957 return 0; 958 959 error_ret: 960 return ret; 961 } 962 963 static int at91_adc_probe_pdata(struct at91_adc_state *st, 964 struct platform_device *pdev) 965 { 966 struct at91_adc_data *pdata = pdev->dev.platform_data; 967 968 if (!pdata) 969 return -EINVAL; 970 971 st->caps = (struct at91_adc_caps *) 972 platform_get_device_id(pdev)->driver_data; 973 974 st->use_external = pdata->use_external_triggers; 975 st->vref_mv = pdata->vref; 976 st->channels_mask = pdata->channels_used; 977 st->num_channels = st->caps->num_channels; 978 st->startup_time = pdata->startup_time; 979 st->trigger_number = pdata->trigger_number; 980 st->trigger_list = pdata->trigger_list; 981 st->registers = &st->caps->registers; 982 st->touchscreen_type = pdata->touchscreen_type; 983 984 return 0; 985 } 986 987 static const struct iio_info at91_adc_info = { 988 .read_raw = &at91_adc_read_raw, 989 }; 990 991 /* Touchscreen related functions */ 992 static int atmel_ts_open(struct input_dev *dev) 993 { 994 struct at91_adc_state *st = input_get_drvdata(dev); 995 996 if (st->caps->has_tsmr) 997 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN); 998 else 999 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN); 1000 return 0; 1001 } 1002 1003 static void atmel_ts_close(struct input_dev *dev) 1004 { 1005 struct at91_adc_state *st = input_get_drvdata(dev); 1006 1007 if (st->caps->has_tsmr) 1008 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN); 1009 else 1010 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN); 1011 } 1012 1013 static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz) 1014 { 1015 struct iio_dev *idev = iio_priv_to_dev(st); 1016 u32 reg = 0; 1017 u32 tssctim = 0; 1018 int i = 0; 1019 1020 /* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid 1021 * pen detect noise. 1022 * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock 1023 */ 1024 st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz / 1025 1000, 1); 1026 1027 while (st->ts_pendbc >> ++i) 1028 ; /* Empty! Find the shift offset */ 1029 if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1)))) 1030 st->ts_pendbc = i; 1031 else 1032 st->ts_pendbc = i - 1; 1033 1034 if (!st->caps->has_tsmr) { 1035 reg = at91_adc_readl(st, AT91_ADC_MR); 1036 reg |= AT91_ADC_TSAMOD_TS_ONLY_MODE | AT91_ADC_PENDET; 1037 1038 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC; 1039 at91_adc_writel(st, AT91_ADC_MR, reg); 1040 1041 reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM; 1042 at91_adc_writel(st, AT91_ADC_TSR, reg); 1043 1044 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL * 1045 adc_clk_khz / 1000) - 1, 1); 1046 1047 return 0; 1048 } 1049 1050 /* Touchscreen Switches Closure time needed for allowing the value to 1051 * stabilize. 1052 * Switch Closure Time = (TSSCTIM * 4) ADCClock periods 1053 */ 1054 tssctim = DIV_ROUND_UP(TOUCH_SCTIM_US * adc_clk_khz / 1000, 4); 1055 dev_dbg(&idev->dev, "adc_clk at: %d KHz, tssctim at: %d\n", 1056 adc_clk_khz, tssctim); 1057 1058 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE) 1059 reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS; 1060 else 1061 reg = AT91_ADC_TSMR_TSMODE_5WIRE; 1062 1063 reg |= AT91_ADC_TSMR_SCTIM_(tssctim) & AT91_ADC_TSMR_SCTIM; 1064 reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average) 1065 & AT91_ADC_TSMR_TSAV; 1066 reg |= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC; 1067 reg |= AT91_ADC_TSMR_NOTSDMA; 1068 reg |= AT91_ADC_TSMR_PENDET_ENA; 1069 reg |= 0x03 << 8; /* TSFREQ, needs to be bigger than TSAV */ 1070 1071 at91_adc_writel(st, AT91_ADC_TSMR, reg); 1072 1073 /* Change adc internal resistor value for better pen detection, 1074 * default value is 100 kOhm. 1075 * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm 1076 * option only available on ES2 and higher 1077 */ 1078 at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity 1079 & AT91_ADC_ACR_PENDETSENS); 1080 1081 /* Sample Period Time = (TRGPER + 1) / ADCClock */ 1082 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US * 1083 adc_clk_khz / 1000) - 1, 1); 1084 1085 return 0; 1086 } 1087 1088 static int at91_ts_register(struct at91_adc_state *st, 1089 struct platform_device *pdev) 1090 { 1091 struct input_dev *input; 1092 struct iio_dev *idev = iio_priv_to_dev(st); 1093 int ret; 1094 1095 input = input_allocate_device(); 1096 if (!input) { 1097 dev_err(&idev->dev, "Failed to allocate TS device!\n"); 1098 return -ENOMEM; 1099 } 1100 1101 input->name = DRIVER_NAME; 1102 input->id.bustype = BUS_HOST; 1103 input->dev.parent = &pdev->dev; 1104 input->open = atmel_ts_open; 1105 input->close = atmel_ts_close; 1106 1107 __set_bit(EV_ABS, input->evbit); 1108 __set_bit(EV_KEY, input->evbit); 1109 __set_bit(BTN_TOUCH, input->keybit); 1110 if (st->caps->has_tsmr) { 1111 input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1, 1112 0, 0); 1113 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1, 1114 0, 0); 1115 input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0); 1116 } else { 1117 if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) { 1118 dev_err(&pdev->dev, 1119 "This touchscreen controller only support 4 wires\n"); 1120 ret = -EINVAL; 1121 goto err; 1122 } 1123 1124 input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1, 1125 0, 0); 1126 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1, 1127 0, 0); 1128 } 1129 1130 st->ts_input = input; 1131 input_set_drvdata(input, st); 1132 1133 ret = input_register_device(input); 1134 if (ret) 1135 goto err; 1136 1137 return ret; 1138 1139 err: 1140 input_free_device(st->ts_input); 1141 return ret; 1142 } 1143 1144 static void at91_ts_unregister(struct at91_adc_state *st) 1145 { 1146 input_unregister_device(st->ts_input); 1147 } 1148 1149 static int at91_adc_probe(struct platform_device *pdev) 1150 { 1151 unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim; 1152 int ret; 1153 struct iio_dev *idev; 1154 struct at91_adc_state *st; 1155 u32 reg; 1156 1157 idev = devm_iio_device_alloc(&pdev->dev, sizeof(struct at91_adc_state)); 1158 if (!idev) 1159 return -ENOMEM; 1160 1161 st = iio_priv(idev); 1162 1163 if (pdev->dev.of_node) 1164 ret = at91_adc_probe_dt(st, pdev); 1165 else 1166 ret = at91_adc_probe_pdata(st, pdev); 1167 1168 if (ret) { 1169 dev_err(&pdev->dev, "No platform data available.\n"); 1170 return -EINVAL; 1171 } 1172 1173 platform_set_drvdata(pdev, idev); 1174 1175 idev->dev.parent = &pdev->dev; 1176 idev->name = dev_name(&pdev->dev); 1177 idev->modes = INDIO_DIRECT_MODE; 1178 idev->info = &at91_adc_info; 1179 1180 st->irq = platform_get_irq(pdev, 0); 1181 if (st->irq < 0) 1182 return -ENODEV; 1183 1184 st->reg_base = devm_platform_ioremap_resource(pdev, 0); 1185 if (IS_ERR(st->reg_base)) 1186 return PTR_ERR(st->reg_base); 1187 1188 1189 /* 1190 * Disable all IRQs before setting up the handler 1191 */ 1192 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST); 1193 at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF); 1194 1195 if (st->caps->has_tsmr) 1196 ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0, 1197 pdev->dev.driver->name, idev); 1198 else 1199 ret = request_irq(st->irq, at91_adc_rl_interrupt, 0, 1200 pdev->dev.driver->name, idev); 1201 if (ret) { 1202 dev_err(&pdev->dev, "Failed to allocate IRQ.\n"); 1203 return ret; 1204 } 1205 1206 st->clk = devm_clk_get(&pdev->dev, "adc_clk"); 1207 if (IS_ERR(st->clk)) { 1208 dev_err(&pdev->dev, "Failed to get the clock.\n"); 1209 ret = PTR_ERR(st->clk); 1210 goto error_free_irq; 1211 } 1212 1213 ret = clk_prepare_enable(st->clk); 1214 if (ret) { 1215 dev_err(&pdev->dev, 1216 "Could not prepare or enable the clock.\n"); 1217 goto error_free_irq; 1218 } 1219 1220 st->adc_clk = devm_clk_get(&pdev->dev, "adc_op_clk"); 1221 if (IS_ERR(st->adc_clk)) { 1222 dev_err(&pdev->dev, "Failed to get the ADC clock.\n"); 1223 ret = PTR_ERR(st->adc_clk); 1224 goto error_disable_clk; 1225 } 1226 1227 ret = clk_prepare_enable(st->adc_clk); 1228 if (ret) { 1229 dev_err(&pdev->dev, 1230 "Could not prepare or enable the ADC clock.\n"); 1231 goto error_disable_clk; 1232 } 1233 1234 /* 1235 * Prescaler rate computation using the formula from the Atmel's 1236 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being 1237 * specified by the electrical characteristics of the board. 1238 */ 1239 mstrclk = clk_get_rate(st->clk); 1240 adc_clk = clk_get_rate(st->adc_clk); 1241 adc_clk_khz = adc_clk / 1000; 1242 1243 dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n", 1244 mstrclk, adc_clk); 1245 1246 prsc = (mstrclk / (2 * adc_clk)) - 1; 1247 1248 if (!st->startup_time) { 1249 dev_err(&pdev->dev, "No startup time available.\n"); 1250 ret = -EINVAL; 1251 goto error_disable_adc_clk; 1252 } 1253 ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz); 1254 1255 /* 1256 * a minimal Sample and Hold Time is necessary for the ADC to guarantee 1257 * the best converted final value between two channels selection 1258 * The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock 1259 */ 1260 if (st->sample_hold_time > 0) 1261 shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000) 1262 - 1, 1); 1263 else 1264 shtim = 0; 1265 1266 reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask; 1267 reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask; 1268 if (st->low_res) 1269 reg |= AT91_ADC_LOWRES; 1270 if (st->sleep_mode) 1271 reg |= AT91_ADC_SLEEP; 1272 reg |= AT91_ADC_SHTIM_(shtim) & AT91_ADC_SHTIM; 1273 at91_adc_writel(st, AT91_ADC_MR, reg); 1274 1275 /* Setup the ADC channels available on the board */ 1276 ret = at91_adc_channel_init(idev); 1277 if (ret < 0) { 1278 dev_err(&pdev->dev, "Couldn't initialize the channels.\n"); 1279 goto error_disable_adc_clk; 1280 } 1281 1282 init_waitqueue_head(&st->wq_data_avail); 1283 mutex_init(&st->lock); 1284 1285 /* 1286 * Since touch screen will set trigger register as period trigger. So 1287 * when touch screen is enabled, then we have to disable hardware 1288 * trigger for classic adc. 1289 */ 1290 if (!st->touchscreen_type) { 1291 ret = at91_adc_buffer_init(idev); 1292 if (ret < 0) { 1293 dev_err(&pdev->dev, "Couldn't initialize the buffer.\n"); 1294 goto error_disable_adc_clk; 1295 } 1296 1297 ret = at91_adc_trigger_init(idev); 1298 if (ret < 0) { 1299 dev_err(&pdev->dev, "Couldn't setup the triggers.\n"); 1300 at91_adc_buffer_remove(idev); 1301 goto error_disable_adc_clk; 1302 } 1303 } else { 1304 ret = at91_ts_register(st, pdev); 1305 if (ret) 1306 goto error_disable_adc_clk; 1307 1308 at91_ts_hw_init(st, adc_clk_khz); 1309 } 1310 1311 ret = iio_device_register(idev); 1312 if (ret < 0) { 1313 dev_err(&pdev->dev, "Couldn't register the device.\n"); 1314 goto error_iio_device_register; 1315 } 1316 1317 return 0; 1318 1319 error_iio_device_register: 1320 if (!st->touchscreen_type) { 1321 at91_adc_trigger_remove(idev); 1322 at91_adc_buffer_remove(idev); 1323 } else { 1324 at91_ts_unregister(st); 1325 } 1326 error_disable_adc_clk: 1327 clk_disable_unprepare(st->adc_clk); 1328 error_disable_clk: 1329 clk_disable_unprepare(st->clk); 1330 error_free_irq: 1331 free_irq(st->irq, idev); 1332 return ret; 1333 } 1334 1335 static int at91_adc_remove(struct platform_device *pdev) 1336 { 1337 struct iio_dev *idev = platform_get_drvdata(pdev); 1338 struct at91_adc_state *st = iio_priv(idev); 1339 1340 iio_device_unregister(idev); 1341 if (!st->touchscreen_type) { 1342 at91_adc_trigger_remove(idev); 1343 at91_adc_buffer_remove(idev); 1344 } else { 1345 at91_ts_unregister(st); 1346 } 1347 clk_disable_unprepare(st->adc_clk); 1348 clk_disable_unprepare(st->clk); 1349 free_irq(st->irq, idev); 1350 1351 return 0; 1352 } 1353 1354 #ifdef CONFIG_PM_SLEEP 1355 static int at91_adc_suspend(struct device *dev) 1356 { 1357 struct iio_dev *idev = dev_get_drvdata(dev); 1358 struct at91_adc_state *st = iio_priv(idev); 1359 1360 pinctrl_pm_select_sleep_state(dev); 1361 clk_disable_unprepare(st->clk); 1362 1363 return 0; 1364 } 1365 1366 static int at91_adc_resume(struct device *dev) 1367 { 1368 struct iio_dev *idev = dev_get_drvdata(dev); 1369 struct at91_adc_state *st = iio_priv(idev); 1370 1371 clk_prepare_enable(st->clk); 1372 pinctrl_pm_select_default_state(dev); 1373 1374 return 0; 1375 } 1376 #endif 1377 1378 static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume); 1379 1380 static struct at91_adc_caps at91sam9260_caps = { 1381 .calc_startup_ticks = calc_startup_ticks_9260, 1382 .num_channels = 4, 1383 .registers = { 1384 .channel_base = AT91_ADC_CHR(0), 1385 .drdy_mask = AT91_ADC_DRDY, 1386 .status_register = AT91_ADC_SR, 1387 .trigger_register = AT91_ADC_TRGR_9260, 1388 .mr_prescal_mask = AT91_ADC_PRESCAL_9260, 1389 .mr_startup_mask = AT91_ADC_STARTUP_9260, 1390 }, 1391 }; 1392 1393 static struct at91_adc_caps at91sam9rl_caps = { 1394 .has_ts = true, 1395 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */ 1396 .num_channels = 6, 1397 .registers = { 1398 .channel_base = AT91_ADC_CHR(0), 1399 .drdy_mask = AT91_ADC_DRDY, 1400 .status_register = AT91_ADC_SR, 1401 .trigger_register = AT91_ADC_TRGR_9G45, 1402 .mr_prescal_mask = AT91_ADC_PRESCAL_9260, 1403 .mr_startup_mask = AT91_ADC_STARTUP_9G45, 1404 }, 1405 }; 1406 1407 static struct at91_adc_caps at91sam9g45_caps = { 1408 .has_ts = true, 1409 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */ 1410 .num_channels = 8, 1411 .registers = { 1412 .channel_base = AT91_ADC_CHR(0), 1413 .drdy_mask = AT91_ADC_DRDY, 1414 .status_register = AT91_ADC_SR, 1415 .trigger_register = AT91_ADC_TRGR_9G45, 1416 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45, 1417 .mr_startup_mask = AT91_ADC_STARTUP_9G45, 1418 }, 1419 }; 1420 1421 static struct at91_adc_caps at91sam9x5_caps = { 1422 .has_ts = true, 1423 .has_tsmr = true, 1424 .ts_filter_average = 3, 1425 .ts_pen_detect_sensitivity = 2, 1426 .calc_startup_ticks = calc_startup_ticks_9x5, 1427 .num_channels = 12, 1428 .registers = { 1429 .channel_base = AT91_ADC_CDR0_9X5, 1430 .drdy_mask = AT91_ADC_SR_DRDY_9X5, 1431 .status_register = AT91_ADC_SR_9X5, 1432 .trigger_register = AT91_ADC_TRGR_9X5, 1433 /* prescal mask is same as 9G45 */ 1434 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45, 1435 .mr_startup_mask = AT91_ADC_STARTUP_9X5, 1436 }, 1437 }; 1438 1439 static const struct of_device_id at91_adc_dt_ids[] = { 1440 { .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps }, 1441 { .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps }, 1442 { .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps }, 1443 { .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps }, 1444 {}, 1445 }; 1446 MODULE_DEVICE_TABLE(of, at91_adc_dt_ids); 1447 1448 static const struct platform_device_id at91_adc_ids[] = { 1449 { 1450 .name = "at91sam9260-adc", 1451 .driver_data = (unsigned long)&at91sam9260_caps, 1452 }, { 1453 .name = "at91sam9rl-adc", 1454 .driver_data = (unsigned long)&at91sam9rl_caps, 1455 }, { 1456 .name = "at91sam9g45-adc", 1457 .driver_data = (unsigned long)&at91sam9g45_caps, 1458 }, { 1459 .name = "at91sam9x5-adc", 1460 .driver_data = (unsigned long)&at91sam9x5_caps, 1461 }, { 1462 /* terminator */ 1463 } 1464 }; 1465 MODULE_DEVICE_TABLE(platform, at91_adc_ids); 1466 1467 static struct platform_driver at91_adc_driver = { 1468 .probe = at91_adc_probe, 1469 .remove = at91_adc_remove, 1470 .id_table = at91_adc_ids, 1471 .driver = { 1472 .name = DRIVER_NAME, 1473 .of_match_table = of_match_ptr(at91_adc_dt_ids), 1474 .pm = &at91_adc_pm_ops, 1475 }, 1476 }; 1477 1478 module_platform_driver(at91_adc_driver); 1479 1480 MODULE_LICENSE("GPL"); 1481 MODULE_DESCRIPTION("Atmel AT91 ADC Driver"); 1482 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 1483