1 /* 2 * Driver for the ADC present in the Atmel AT91 evaluation boards. 3 * 4 * Copyright 2011 Free Electrons 5 * 6 * Licensed under the GPLv2 or later. 7 */ 8 9 #include <linux/bitmap.h> 10 #include <linux/bitops.h> 11 #include <linux/clk.h> 12 #include <linux/err.h> 13 #include <linux/io.h> 14 #include <linux/input.h> 15 #include <linux/interrupt.h> 16 #include <linux/jiffies.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 #include <linux/of.h> 20 #include <linux/of_device.h> 21 #include <linux/platform_device.h> 22 #include <linux/sched.h> 23 #include <linux/slab.h> 24 #include <linux/wait.h> 25 26 #include <linux/platform_data/at91_adc.h> 27 28 #include <linux/iio/iio.h> 29 #include <linux/iio/buffer.h> 30 #include <linux/iio/trigger.h> 31 #include <linux/iio/trigger_consumer.h> 32 #include <linux/iio/triggered_buffer.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_PENDBC (0x0f << 28) /* Pen Debounce time */ 117 #define AT91_ADC_TSMR_PENDBC_(x) ((x) << 28) 118 #define AT91_ADC_TSMR_NOTSDMA (1 << 22) /* No Touchscreen DMA */ 119 #define AT91_ADC_TSMR_PENDET_DIS (0 << 24) /* Pen contact detection disable */ 120 #define AT91_ADC_TSMR_PENDET_ENA (1 << 24) /* Pen contact detection enable */ 121 122 #define AT91_ADC_TSXPOSR 0xB4 123 #define AT91_ADC_TSYPOSR 0xB8 124 #define AT91_ADC_TSPRESSR 0xBC 125 126 #define AT91_ADC_TRGR_9260 AT91_ADC_MR 127 #define AT91_ADC_TRGR_9G45 0x08 128 #define AT91_ADC_TRGR_9X5 0xC0 129 130 /* Trigger Register bit field */ 131 #define AT91_ADC_TRGR_TRGPER (0xffff << 16) 132 #define AT91_ADC_TRGR_TRGPER_(x) ((x) << 16) 133 #define AT91_ADC_TRGR_TRGMOD (0x7 << 0) 134 #define AT91_ADC_TRGR_NONE (0 << 0) 135 #define AT91_ADC_TRGR_MOD_PERIOD_TRIG (5 << 0) 136 137 #define AT91_ADC_CHAN(st, ch) \ 138 (st->registers->channel_base + (ch * 4)) 139 #define at91_adc_readl(st, reg) \ 140 (readl_relaxed(st->reg_base + reg)) 141 #define at91_adc_writel(st, reg, val) \ 142 (writel_relaxed(val, st->reg_base + reg)) 143 144 #define DRIVER_NAME "at91_adc" 145 #define MAX_POS_BITS 12 146 147 #define TOUCH_SAMPLE_PERIOD_US 2000 /* 2ms */ 148 #define TOUCH_PEN_DETECT_DEBOUNCE_US 200 149 150 #define MAX_RLPOS_BITS 10 151 #define TOUCH_SAMPLE_PERIOD_US_RL 10000 /* 10ms, the SoC can't keep up with 2ms */ 152 #define TOUCH_SHTIM 0xa 153 154 /** 155 * struct at91_adc_reg_desc - Various informations relative to registers 156 * @channel_base: Base offset for the channel data registers 157 * @drdy_mask: Mask of the DRDY field in the relevant registers 158 (Interruptions registers mostly) 159 * @status_register: Offset of the Interrupt Status Register 160 * @trigger_register: Offset of the Trigger setup register 161 * @mr_prescal_mask: Mask of the PRESCAL field in the adc MR register 162 * @mr_startup_mask: Mask of the STARTUP field in the adc MR register 163 */ 164 struct at91_adc_reg_desc { 165 u8 channel_base; 166 u32 drdy_mask; 167 u8 status_register; 168 u8 trigger_register; 169 u32 mr_prescal_mask; 170 u32 mr_startup_mask; 171 }; 172 173 struct at91_adc_caps { 174 bool has_ts; /* Support touch screen */ 175 bool has_tsmr; /* only at91sam9x5, sama5d3 have TSMR reg */ 176 /* 177 * Numbers of sampling data will be averaged. Can be 0~3. 178 * Hardware can average (2 ^ ts_filter_average) sample data. 179 */ 180 u8 ts_filter_average; 181 /* Pen Detection input pull-up resistor, can be 0~3 */ 182 u8 ts_pen_detect_sensitivity; 183 184 /* startup time calculate function */ 185 u32 (*calc_startup_ticks)(u8 startup_time, u32 adc_clk_khz); 186 187 u8 num_channels; 188 struct at91_adc_reg_desc registers; 189 }; 190 191 struct at91_adc_state { 192 struct clk *adc_clk; 193 u16 *buffer; 194 unsigned long channels_mask; 195 struct clk *clk; 196 bool done; 197 int irq; 198 u16 last_value; 199 int chnb; 200 struct mutex lock; 201 u8 num_channels; 202 void __iomem *reg_base; 203 struct at91_adc_reg_desc *registers; 204 u8 startup_time; 205 u8 sample_hold_time; 206 bool sleep_mode; 207 struct iio_trigger **trig; 208 struct at91_adc_trigger *trigger_list; 209 u32 trigger_number; 210 bool use_external; 211 u32 vref_mv; 212 u32 res; /* resolution used for convertions */ 213 bool low_res; /* the resolution corresponds to the lowest one */ 214 wait_queue_head_t wq_data_avail; 215 struct at91_adc_caps *caps; 216 217 /* 218 * Following ADC channels are shared by touchscreen: 219 * 220 * CH0 -- Touch screen XP/UL 221 * CH1 -- Touch screen XM/UR 222 * CH2 -- Touch screen YP/LL 223 * CH3 -- Touch screen YM/Sense 224 * CH4 -- Touch screen LR(5-wire only) 225 * 226 * The bitfields below represents the reserved channel in the 227 * touchscreen mode. 228 */ 229 #define CHAN_MASK_TOUCHSCREEN_4WIRE (0xf << 0) 230 #define CHAN_MASK_TOUCHSCREEN_5WIRE (0x1f << 0) 231 enum atmel_adc_ts_type touchscreen_type; 232 struct input_dev *ts_input; 233 234 u16 ts_sample_period_val; 235 u32 ts_pressure_threshold; 236 u16 ts_pendbc; 237 238 bool ts_bufferedmeasure; 239 u32 ts_prev_absx; 240 u32 ts_prev_absy; 241 }; 242 243 static irqreturn_t at91_adc_trigger_handler(int irq, void *p) 244 { 245 struct iio_poll_func *pf = p; 246 struct iio_dev *idev = pf->indio_dev; 247 struct at91_adc_state *st = iio_priv(idev); 248 int i, j = 0; 249 250 for (i = 0; i < idev->masklength; i++) { 251 if (!test_bit(i, idev->active_scan_mask)) 252 continue; 253 st->buffer[j] = at91_adc_readl(st, AT91_ADC_CHAN(st, i)); 254 j++; 255 } 256 257 iio_push_to_buffers_with_timestamp(idev, st->buffer, pf->timestamp); 258 259 iio_trigger_notify_done(idev->trig); 260 261 /* Needed to ACK the DRDY interruption */ 262 at91_adc_readl(st, AT91_ADC_LCDR); 263 264 enable_irq(st->irq); 265 266 return IRQ_HANDLED; 267 } 268 269 /* Handler for classic adc channel eoc trigger */ 270 static void handle_adc_eoc_trigger(int irq, struct iio_dev *idev) 271 { 272 struct at91_adc_state *st = iio_priv(idev); 273 274 if (iio_buffer_enabled(idev)) { 275 disable_irq_nosync(irq); 276 iio_trigger_poll(idev->trig); 277 } else { 278 st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb)); 279 st->done = true; 280 wake_up_interruptible(&st->wq_data_avail); 281 } 282 } 283 284 static int at91_ts_sample(struct at91_adc_state *st) 285 { 286 unsigned int xscale, yscale, reg, z1, z2; 287 unsigned int x, y, pres, xpos, ypos; 288 unsigned int rxp = 1; 289 unsigned int factor = 1000; 290 struct iio_dev *idev = iio_priv_to_dev(st); 291 292 unsigned int xyz_mask_bits = st->res; 293 unsigned int xyz_mask = (1 << xyz_mask_bits) - 1; 294 295 /* calculate position */ 296 /* x position = (x / xscale) * max, max = 2^MAX_POS_BITS - 1 */ 297 reg = at91_adc_readl(st, AT91_ADC_TSXPOSR); 298 xpos = reg & xyz_mask; 299 x = (xpos << MAX_POS_BITS) - xpos; 300 xscale = (reg >> 16) & xyz_mask; 301 if (xscale == 0) { 302 dev_err(&idev->dev, "Error: xscale == 0!\n"); 303 return -1; 304 } 305 x /= xscale; 306 307 /* y position = (y / yscale) * max, max = 2^MAX_POS_BITS - 1 */ 308 reg = at91_adc_readl(st, AT91_ADC_TSYPOSR); 309 ypos = reg & xyz_mask; 310 y = (ypos << MAX_POS_BITS) - ypos; 311 yscale = (reg >> 16) & xyz_mask; 312 if (yscale == 0) { 313 dev_err(&idev->dev, "Error: yscale == 0!\n"); 314 return -1; 315 } 316 y /= yscale; 317 318 /* calculate the pressure */ 319 reg = at91_adc_readl(st, AT91_ADC_TSPRESSR); 320 z1 = reg & xyz_mask; 321 z2 = (reg >> 16) & xyz_mask; 322 323 if (z1 != 0) 324 pres = rxp * (x * factor / 1024) * (z2 * factor / z1 - factor) 325 / factor; 326 else 327 pres = st->ts_pressure_threshold; /* no pen contacted */ 328 329 dev_dbg(&idev->dev, "xpos = %d, xscale = %d, ypos = %d, yscale = %d, z1 = %d, z2 = %d, press = %d\n", 330 xpos, xscale, ypos, yscale, z1, z2, pres); 331 332 if (pres < st->ts_pressure_threshold) { 333 dev_dbg(&idev->dev, "x = %d, y = %d, pressure = %d\n", 334 x, y, pres / factor); 335 input_report_abs(st->ts_input, ABS_X, x); 336 input_report_abs(st->ts_input, ABS_Y, y); 337 input_report_abs(st->ts_input, ABS_PRESSURE, pres); 338 input_report_key(st->ts_input, BTN_TOUCH, 1); 339 input_sync(st->ts_input); 340 } else { 341 dev_dbg(&idev->dev, "pressure too low: not reporting\n"); 342 } 343 344 return 0; 345 } 346 347 static irqreturn_t at91_adc_rl_interrupt(int irq, void *private) 348 { 349 struct iio_dev *idev = private; 350 struct at91_adc_state *st = iio_priv(idev); 351 u32 status = at91_adc_readl(st, st->registers->status_register); 352 unsigned int reg; 353 354 status &= at91_adc_readl(st, AT91_ADC_IMR); 355 if (status & GENMASK(st->num_channels - 1, 0)) 356 handle_adc_eoc_trigger(irq, idev); 357 358 if (status & AT91RL_ADC_IER_PEN) { 359 /* Disabling pen debounce is required to get a NOPEN irq */ 360 reg = at91_adc_readl(st, AT91_ADC_MR); 361 reg &= ~AT91_ADC_PENDBC; 362 at91_adc_writel(st, AT91_ADC_MR, reg); 363 364 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN); 365 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_NOPEN 366 | AT91_ADC_EOC(3)); 367 /* Set up period trigger for sampling */ 368 at91_adc_writel(st, st->registers->trigger_register, 369 AT91_ADC_TRGR_MOD_PERIOD_TRIG | 370 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val)); 371 } else if (status & AT91RL_ADC_IER_NOPEN) { 372 reg = at91_adc_readl(st, AT91_ADC_MR); 373 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC; 374 at91_adc_writel(st, AT91_ADC_MR, reg); 375 at91_adc_writel(st, st->registers->trigger_register, 376 AT91_ADC_TRGR_NONE); 377 378 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_NOPEN 379 | AT91_ADC_EOC(3)); 380 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN); 381 st->ts_bufferedmeasure = false; 382 input_report_key(st->ts_input, BTN_TOUCH, 0); 383 input_sync(st->ts_input); 384 } else if (status & AT91_ADC_EOC(3)) { 385 /* Conversion finished */ 386 if (st->ts_bufferedmeasure) { 387 /* 388 * Last measurement is always discarded, since it can 389 * be erroneous. 390 * Always report previous measurement 391 */ 392 input_report_abs(st->ts_input, ABS_X, st->ts_prev_absx); 393 input_report_abs(st->ts_input, ABS_Y, st->ts_prev_absy); 394 input_report_key(st->ts_input, BTN_TOUCH, 1); 395 input_sync(st->ts_input); 396 } else 397 st->ts_bufferedmeasure = true; 398 399 /* Now make new measurement */ 400 st->ts_prev_absx = at91_adc_readl(st, AT91_ADC_CHAN(st, 3)) 401 << MAX_RLPOS_BITS; 402 st->ts_prev_absx /= at91_adc_readl(st, AT91_ADC_CHAN(st, 2)); 403 404 st->ts_prev_absy = at91_adc_readl(st, AT91_ADC_CHAN(st, 1)) 405 << MAX_RLPOS_BITS; 406 st->ts_prev_absy /= at91_adc_readl(st, AT91_ADC_CHAN(st, 0)); 407 } 408 409 return IRQ_HANDLED; 410 } 411 412 static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private) 413 { 414 struct iio_dev *idev = private; 415 struct at91_adc_state *st = iio_priv(idev); 416 u32 status = at91_adc_readl(st, st->registers->status_register); 417 const uint32_t ts_data_irq_mask = 418 AT91_ADC_IER_XRDY | 419 AT91_ADC_IER_YRDY | 420 AT91_ADC_IER_PRDY; 421 422 if (status & GENMASK(st->num_channels - 1, 0)) 423 handle_adc_eoc_trigger(irq, idev); 424 425 if (status & AT91_ADC_IER_PEN) { 426 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN); 427 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_NOPEN | 428 ts_data_irq_mask); 429 /* Set up period trigger for sampling */ 430 at91_adc_writel(st, st->registers->trigger_register, 431 AT91_ADC_TRGR_MOD_PERIOD_TRIG | 432 AT91_ADC_TRGR_TRGPER_(st->ts_sample_period_val)); 433 } else if (status & AT91_ADC_IER_NOPEN) { 434 at91_adc_writel(st, st->registers->trigger_register, 0); 435 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_NOPEN | 436 ts_data_irq_mask); 437 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN); 438 439 input_report_key(st->ts_input, BTN_TOUCH, 0); 440 input_sync(st->ts_input); 441 } else if ((status & ts_data_irq_mask) == ts_data_irq_mask) { 442 /* Now all touchscreen data is ready */ 443 444 if (status & AT91_ADC_ISR_PENS) { 445 /* validate data by pen contact */ 446 at91_ts_sample(st); 447 } else { 448 /* triggered by event that is no pen contact, just read 449 * them to clean the interrupt and discard all. 450 */ 451 at91_adc_readl(st, AT91_ADC_TSXPOSR); 452 at91_adc_readl(st, AT91_ADC_TSYPOSR); 453 at91_adc_readl(st, AT91_ADC_TSPRESSR); 454 } 455 } 456 457 return IRQ_HANDLED; 458 } 459 460 static int at91_adc_channel_init(struct iio_dev *idev) 461 { 462 struct at91_adc_state *st = iio_priv(idev); 463 struct iio_chan_spec *chan_array, *timestamp; 464 int bit, idx = 0; 465 unsigned long rsvd_mask = 0; 466 467 /* If touchscreen is enable, then reserve the adc channels */ 468 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE) 469 rsvd_mask = CHAN_MASK_TOUCHSCREEN_4WIRE; 470 else if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_5WIRE) 471 rsvd_mask = CHAN_MASK_TOUCHSCREEN_5WIRE; 472 473 /* set up the channel mask to reserve touchscreen channels */ 474 st->channels_mask &= ~rsvd_mask; 475 476 idev->num_channels = bitmap_weight(&st->channels_mask, 477 st->num_channels) + 1; 478 479 chan_array = devm_kzalloc(&idev->dev, 480 ((idev->num_channels + 1) * 481 sizeof(struct iio_chan_spec)), 482 GFP_KERNEL); 483 484 if (!chan_array) 485 return -ENOMEM; 486 487 for_each_set_bit(bit, &st->channels_mask, st->num_channels) { 488 struct iio_chan_spec *chan = chan_array + idx; 489 490 chan->type = IIO_VOLTAGE; 491 chan->indexed = 1; 492 chan->channel = bit; 493 chan->scan_index = idx; 494 chan->scan_type.sign = 'u'; 495 chan->scan_type.realbits = st->res; 496 chan->scan_type.storagebits = 16; 497 chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE); 498 chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); 499 idx++; 500 } 501 timestamp = chan_array + idx; 502 503 timestamp->type = IIO_TIMESTAMP; 504 timestamp->channel = -1; 505 timestamp->scan_index = idx; 506 timestamp->scan_type.sign = 's'; 507 timestamp->scan_type.realbits = 64; 508 timestamp->scan_type.storagebits = 64; 509 510 idev->channels = chan_array; 511 return idev->num_channels; 512 } 513 514 static int at91_adc_get_trigger_value_by_name(struct iio_dev *idev, 515 struct at91_adc_trigger *triggers, 516 const char *trigger_name) 517 { 518 struct at91_adc_state *st = iio_priv(idev); 519 int i; 520 521 for (i = 0; i < st->trigger_number; i++) { 522 char *name = kasprintf(GFP_KERNEL, 523 "%s-dev%d-%s", 524 idev->name, 525 idev->id, 526 triggers[i].name); 527 if (!name) 528 return -ENOMEM; 529 530 if (strcmp(trigger_name, name) == 0) { 531 kfree(name); 532 if (triggers[i].value == 0) 533 return -EINVAL; 534 return triggers[i].value; 535 } 536 537 kfree(name); 538 } 539 540 return -EINVAL; 541 } 542 543 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state) 544 { 545 struct iio_dev *idev = iio_trigger_get_drvdata(trig); 546 struct at91_adc_state *st = iio_priv(idev); 547 struct iio_buffer *buffer = idev->buffer; 548 struct at91_adc_reg_desc *reg = st->registers; 549 u32 status = at91_adc_readl(st, reg->trigger_register); 550 int value; 551 u8 bit; 552 553 value = at91_adc_get_trigger_value_by_name(idev, 554 st->trigger_list, 555 idev->trig->name); 556 if (value < 0) 557 return value; 558 559 if (state) { 560 st->buffer = kmalloc(idev->scan_bytes, GFP_KERNEL); 561 if (st->buffer == NULL) 562 return -ENOMEM; 563 564 at91_adc_writel(st, reg->trigger_register, 565 status | value); 566 567 for_each_set_bit(bit, buffer->scan_mask, 568 st->num_channels) { 569 struct iio_chan_spec const *chan = idev->channels + bit; 570 at91_adc_writel(st, AT91_ADC_CHER, 571 AT91_ADC_CH(chan->channel)); 572 } 573 574 at91_adc_writel(st, AT91_ADC_IER, reg->drdy_mask); 575 576 } else { 577 at91_adc_writel(st, AT91_ADC_IDR, reg->drdy_mask); 578 579 at91_adc_writel(st, reg->trigger_register, 580 status & ~value); 581 582 for_each_set_bit(bit, buffer->scan_mask, 583 st->num_channels) { 584 struct iio_chan_spec const *chan = idev->channels + bit; 585 at91_adc_writel(st, AT91_ADC_CHDR, 586 AT91_ADC_CH(chan->channel)); 587 } 588 kfree(st->buffer); 589 } 590 591 return 0; 592 } 593 594 static const struct iio_trigger_ops at91_adc_trigger_ops = { 595 .owner = THIS_MODULE, 596 .set_trigger_state = &at91_adc_configure_trigger, 597 }; 598 599 static struct iio_trigger *at91_adc_allocate_trigger(struct iio_dev *idev, 600 struct at91_adc_trigger *trigger) 601 { 602 struct iio_trigger *trig; 603 int ret; 604 605 trig = iio_trigger_alloc("%s-dev%d-%s", idev->name, 606 idev->id, trigger->name); 607 if (trig == NULL) 608 return NULL; 609 610 trig->dev.parent = idev->dev.parent; 611 iio_trigger_set_drvdata(trig, idev); 612 trig->ops = &at91_adc_trigger_ops; 613 614 ret = iio_trigger_register(trig); 615 if (ret) 616 return NULL; 617 618 return trig; 619 } 620 621 static int at91_adc_trigger_init(struct iio_dev *idev) 622 { 623 struct at91_adc_state *st = iio_priv(idev); 624 int i, ret; 625 626 st->trig = devm_kzalloc(&idev->dev, 627 st->trigger_number * sizeof(*st->trig), 628 GFP_KERNEL); 629 630 if (st->trig == NULL) { 631 ret = -ENOMEM; 632 goto error_ret; 633 } 634 635 for (i = 0; i < st->trigger_number; i++) { 636 if (st->trigger_list[i].is_external && !(st->use_external)) 637 continue; 638 639 st->trig[i] = at91_adc_allocate_trigger(idev, 640 st->trigger_list + i); 641 if (st->trig[i] == NULL) { 642 dev_err(&idev->dev, 643 "Could not allocate trigger %d\n", i); 644 ret = -ENOMEM; 645 goto error_trigger; 646 } 647 } 648 649 return 0; 650 651 error_trigger: 652 for (i--; i >= 0; i--) { 653 iio_trigger_unregister(st->trig[i]); 654 iio_trigger_free(st->trig[i]); 655 } 656 error_ret: 657 return ret; 658 } 659 660 static void at91_adc_trigger_remove(struct iio_dev *idev) 661 { 662 struct at91_adc_state *st = iio_priv(idev); 663 int i; 664 665 for (i = 0; i < st->trigger_number; i++) { 666 iio_trigger_unregister(st->trig[i]); 667 iio_trigger_free(st->trig[i]); 668 } 669 } 670 671 static int at91_adc_buffer_init(struct iio_dev *idev) 672 { 673 return iio_triggered_buffer_setup(idev, &iio_pollfunc_store_time, 674 &at91_adc_trigger_handler, NULL); 675 } 676 677 static void at91_adc_buffer_remove(struct iio_dev *idev) 678 { 679 iio_triggered_buffer_cleanup(idev); 680 } 681 682 static int at91_adc_read_raw(struct iio_dev *idev, 683 struct iio_chan_spec const *chan, 684 int *val, int *val2, long mask) 685 { 686 struct at91_adc_state *st = iio_priv(idev); 687 int ret; 688 689 switch (mask) { 690 case IIO_CHAN_INFO_RAW: 691 mutex_lock(&st->lock); 692 693 st->chnb = chan->channel; 694 at91_adc_writel(st, AT91_ADC_CHER, 695 AT91_ADC_CH(chan->channel)); 696 at91_adc_writel(st, AT91_ADC_IER, BIT(chan->channel)); 697 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START); 698 699 ret = wait_event_interruptible_timeout(st->wq_data_avail, 700 st->done, 701 msecs_to_jiffies(1000)); 702 if (ret == 0) 703 ret = -ETIMEDOUT; 704 if (ret < 0) { 705 mutex_unlock(&st->lock); 706 return ret; 707 } 708 709 *val = st->last_value; 710 711 at91_adc_writel(st, AT91_ADC_CHDR, 712 AT91_ADC_CH(chan->channel)); 713 at91_adc_writel(st, AT91_ADC_IDR, BIT(chan->channel)); 714 715 st->last_value = 0; 716 st->done = false; 717 mutex_unlock(&st->lock); 718 return IIO_VAL_INT; 719 720 case IIO_CHAN_INFO_SCALE: 721 *val = st->vref_mv; 722 *val2 = chan->scan_type.realbits; 723 return IIO_VAL_FRACTIONAL_LOG2; 724 default: 725 break; 726 } 727 return -EINVAL; 728 } 729 730 static int at91_adc_of_get_resolution(struct at91_adc_state *st, 731 struct platform_device *pdev) 732 { 733 struct iio_dev *idev = iio_priv_to_dev(st); 734 struct device_node *np = pdev->dev.of_node; 735 int count, i, ret = 0; 736 char *res_name, *s; 737 u32 *resolutions; 738 739 count = of_property_count_strings(np, "atmel,adc-res-names"); 740 if (count < 2) { 741 dev_err(&idev->dev, "You must specified at least two resolution names for " 742 "adc-res-names property in the DT\n"); 743 return count; 744 } 745 746 resolutions = kmalloc(count * sizeof(*resolutions), GFP_KERNEL); 747 if (!resolutions) 748 return -ENOMEM; 749 750 if (of_property_read_u32_array(np, "atmel,adc-res", resolutions, count)) { 751 dev_err(&idev->dev, "Missing adc-res property in the DT.\n"); 752 ret = -ENODEV; 753 goto ret; 754 } 755 756 if (of_property_read_string(np, "atmel,adc-use-res", (const char **)&res_name)) 757 res_name = "highres"; 758 759 for (i = 0; i < count; i++) { 760 if (of_property_read_string_index(np, "atmel,adc-res-names", i, (const char **)&s)) 761 continue; 762 763 if (strcmp(res_name, s)) 764 continue; 765 766 st->res = resolutions[i]; 767 if (!strcmp(res_name, "lowres")) 768 st->low_res = true; 769 else 770 st->low_res = false; 771 772 dev_info(&idev->dev, "Resolution used: %u bits\n", st->res); 773 goto ret; 774 } 775 776 dev_err(&idev->dev, "There is no resolution for %s\n", res_name); 777 778 ret: 779 kfree(resolutions); 780 return ret; 781 } 782 783 static u32 calc_startup_ticks_9260(u8 startup_time, u32 adc_clk_khz) 784 { 785 /* 786 * Number of ticks needed to cover the startup time of the ADC 787 * as defined in the electrical characteristics of the board, 788 * divided by 8. The formula thus is : 789 * Startup Time = (ticks + 1) * 8 / ADC Clock 790 */ 791 return round_up((startup_time * adc_clk_khz / 1000) - 1, 8) / 8; 792 } 793 794 static u32 calc_startup_ticks_9x5(u8 startup_time, u32 adc_clk_khz) 795 { 796 /* 797 * For sama5d3x and at91sam9x5, the formula changes to: 798 * Startup Time = <lookup_table_value> / ADC Clock 799 */ 800 const int startup_lookup[] = { 801 0 , 8 , 16 , 24 , 802 64 , 80 , 96 , 112, 803 512, 576, 640, 704, 804 768, 832, 896, 960 805 }; 806 int i, size = ARRAY_SIZE(startup_lookup); 807 unsigned int ticks; 808 809 ticks = startup_time * adc_clk_khz / 1000; 810 for (i = 0; i < size; i++) 811 if (ticks < startup_lookup[i]) 812 break; 813 814 ticks = i; 815 if (ticks == size) 816 /* Reach the end of lookup table */ 817 ticks = size - 1; 818 819 return ticks; 820 } 821 822 static const struct of_device_id at91_adc_dt_ids[]; 823 824 static int at91_adc_probe_dt_ts(struct device_node *node, 825 struct at91_adc_state *st, struct device *dev) 826 { 827 int ret; 828 u32 prop; 829 830 ret = of_property_read_u32(node, "atmel,adc-ts-wires", &prop); 831 if (ret) { 832 dev_info(dev, "ADC Touch screen is disabled.\n"); 833 return 0; 834 } 835 836 switch (prop) { 837 case 4: 838 case 5: 839 st->touchscreen_type = prop; 840 break; 841 default: 842 dev_err(dev, "Unsupported number of touchscreen wires (%d). Should be 4 or 5.\n", prop); 843 return -EINVAL; 844 } 845 846 if (!st->caps->has_tsmr) 847 return 0; 848 prop = 0; 849 of_property_read_u32(node, "atmel,adc-ts-pressure-threshold", &prop); 850 st->ts_pressure_threshold = prop; 851 if (st->ts_pressure_threshold) { 852 return 0; 853 } else { 854 dev_err(dev, "Invalid pressure threshold for the touchscreen\n"); 855 return -EINVAL; 856 } 857 } 858 859 static int at91_adc_probe_dt(struct at91_adc_state *st, 860 struct platform_device *pdev) 861 { 862 struct iio_dev *idev = iio_priv_to_dev(st); 863 struct device_node *node = pdev->dev.of_node; 864 struct device_node *trig_node; 865 int i = 0, ret; 866 u32 prop; 867 868 if (!node) 869 return -EINVAL; 870 871 st->caps = (struct at91_adc_caps *) 872 of_match_device(at91_adc_dt_ids, &pdev->dev)->data; 873 874 st->use_external = of_property_read_bool(node, "atmel,adc-use-external-triggers"); 875 876 if (of_property_read_u32(node, "atmel,adc-channels-used", &prop)) { 877 dev_err(&idev->dev, "Missing adc-channels-used property in the DT.\n"); 878 ret = -EINVAL; 879 goto error_ret; 880 } 881 st->channels_mask = prop; 882 883 st->sleep_mode = of_property_read_bool(node, "atmel,adc-sleep-mode"); 884 885 if (of_property_read_u32(node, "atmel,adc-startup-time", &prop)) { 886 dev_err(&idev->dev, "Missing adc-startup-time property in the DT.\n"); 887 ret = -EINVAL; 888 goto error_ret; 889 } 890 st->startup_time = prop; 891 892 prop = 0; 893 of_property_read_u32(node, "atmel,adc-sample-hold-time", &prop); 894 st->sample_hold_time = prop; 895 896 if (of_property_read_u32(node, "atmel,adc-vref", &prop)) { 897 dev_err(&idev->dev, "Missing adc-vref property in the DT.\n"); 898 ret = -EINVAL; 899 goto error_ret; 900 } 901 st->vref_mv = prop; 902 903 ret = at91_adc_of_get_resolution(st, pdev); 904 if (ret) 905 goto error_ret; 906 907 st->registers = &st->caps->registers; 908 st->num_channels = st->caps->num_channels; 909 st->trigger_number = of_get_child_count(node); 910 st->trigger_list = devm_kzalloc(&idev->dev, st->trigger_number * 911 sizeof(struct at91_adc_trigger), 912 GFP_KERNEL); 913 if (!st->trigger_list) { 914 dev_err(&idev->dev, "Could not allocate trigger list memory.\n"); 915 ret = -ENOMEM; 916 goto error_ret; 917 } 918 919 for_each_child_of_node(node, trig_node) { 920 struct at91_adc_trigger *trig = st->trigger_list + i; 921 const char *name; 922 923 if (of_property_read_string(trig_node, "trigger-name", &name)) { 924 dev_err(&idev->dev, "Missing trigger-name property in the DT.\n"); 925 ret = -EINVAL; 926 goto error_ret; 927 } 928 trig->name = name; 929 930 if (of_property_read_u32(trig_node, "trigger-value", &prop)) { 931 dev_err(&idev->dev, "Missing trigger-value property in the DT.\n"); 932 ret = -EINVAL; 933 goto error_ret; 934 } 935 trig->value = prop; 936 trig->is_external = of_property_read_bool(trig_node, "trigger-external"); 937 i++; 938 } 939 940 /* Check if touchscreen is supported. */ 941 if (st->caps->has_ts) 942 return at91_adc_probe_dt_ts(node, st, &idev->dev); 943 else 944 dev_info(&idev->dev, "not support touchscreen in the adc compatible string.\n"); 945 946 return 0; 947 948 error_ret: 949 return ret; 950 } 951 952 static int at91_adc_probe_pdata(struct at91_adc_state *st, 953 struct platform_device *pdev) 954 { 955 struct at91_adc_data *pdata = pdev->dev.platform_data; 956 957 if (!pdata) 958 return -EINVAL; 959 960 st->caps = (struct at91_adc_caps *) 961 platform_get_device_id(pdev)->driver_data; 962 963 st->use_external = pdata->use_external_triggers; 964 st->vref_mv = pdata->vref; 965 st->channels_mask = pdata->channels_used; 966 st->num_channels = st->caps->num_channels; 967 st->startup_time = pdata->startup_time; 968 st->trigger_number = pdata->trigger_number; 969 st->trigger_list = pdata->trigger_list; 970 st->registers = &st->caps->registers; 971 st->touchscreen_type = pdata->touchscreen_type; 972 973 return 0; 974 } 975 976 static const struct iio_info at91_adc_info = { 977 .driver_module = THIS_MODULE, 978 .read_raw = &at91_adc_read_raw, 979 }; 980 981 /* Touchscreen related functions */ 982 static int atmel_ts_open(struct input_dev *dev) 983 { 984 struct at91_adc_state *st = input_get_drvdata(dev); 985 986 if (st->caps->has_tsmr) 987 at91_adc_writel(st, AT91_ADC_IER, AT91_ADC_IER_PEN); 988 else 989 at91_adc_writel(st, AT91_ADC_IER, AT91RL_ADC_IER_PEN); 990 return 0; 991 } 992 993 static void atmel_ts_close(struct input_dev *dev) 994 { 995 struct at91_adc_state *st = input_get_drvdata(dev); 996 997 if (st->caps->has_tsmr) 998 at91_adc_writel(st, AT91_ADC_IDR, AT91_ADC_IER_PEN); 999 else 1000 at91_adc_writel(st, AT91_ADC_IDR, AT91RL_ADC_IER_PEN); 1001 } 1002 1003 static int at91_ts_hw_init(struct at91_adc_state *st, u32 adc_clk_khz) 1004 { 1005 u32 reg = 0; 1006 int i = 0; 1007 1008 /* a Pen Detect Debounce Time is necessary for the ADC Touch to avoid 1009 * pen detect noise. 1010 * The formula is : Pen Detect Debounce Time = (2 ^ pendbc) / ADCClock 1011 */ 1012 st->ts_pendbc = round_up(TOUCH_PEN_DETECT_DEBOUNCE_US * adc_clk_khz / 1013 1000, 1); 1014 1015 while (st->ts_pendbc >> ++i) 1016 ; /* Empty! Find the shift offset */ 1017 if (abs(st->ts_pendbc - (1 << i)) < abs(st->ts_pendbc - (1 << (i - 1)))) 1018 st->ts_pendbc = i; 1019 else 1020 st->ts_pendbc = i - 1; 1021 1022 if (!st->caps->has_tsmr) { 1023 reg = at91_adc_readl(st, AT91_ADC_MR); 1024 reg |= AT91_ADC_TSAMOD_TS_ONLY_MODE | AT91_ADC_PENDET; 1025 1026 reg |= AT91_ADC_PENDBC_(st->ts_pendbc) & AT91_ADC_PENDBC; 1027 at91_adc_writel(st, AT91_ADC_MR, reg); 1028 1029 reg = AT91_ADC_TSR_SHTIM_(TOUCH_SHTIM) & AT91_ADC_TSR_SHTIM; 1030 at91_adc_writel(st, AT91_ADC_TSR, reg); 1031 1032 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US_RL * 1033 adc_clk_khz / 1000) - 1, 1); 1034 1035 return 0; 1036 } 1037 1038 if (st->touchscreen_type == ATMEL_ADC_TOUCHSCREEN_4WIRE) 1039 reg = AT91_ADC_TSMR_TSMODE_4WIRE_PRESS; 1040 else 1041 reg = AT91_ADC_TSMR_TSMODE_5WIRE; 1042 1043 reg |= AT91_ADC_TSMR_TSAV_(st->caps->ts_filter_average) 1044 & AT91_ADC_TSMR_TSAV; 1045 reg |= AT91_ADC_TSMR_PENDBC_(st->ts_pendbc) & AT91_ADC_TSMR_PENDBC; 1046 reg |= AT91_ADC_TSMR_NOTSDMA; 1047 reg |= AT91_ADC_TSMR_PENDET_ENA; 1048 reg |= 0x03 << 8; /* TSFREQ, needs to be bigger than TSAV */ 1049 1050 at91_adc_writel(st, AT91_ADC_TSMR, reg); 1051 1052 /* Change adc internal resistor value for better pen detection, 1053 * default value is 100 kOhm. 1054 * 0 = 200 kOhm, 1 = 150 kOhm, 2 = 100 kOhm, 3 = 50 kOhm 1055 * option only available on ES2 and higher 1056 */ 1057 at91_adc_writel(st, AT91_ADC_ACR, st->caps->ts_pen_detect_sensitivity 1058 & AT91_ADC_ACR_PENDETSENS); 1059 1060 /* Sample Period Time = (TRGPER + 1) / ADCClock */ 1061 st->ts_sample_period_val = round_up((TOUCH_SAMPLE_PERIOD_US * 1062 adc_clk_khz / 1000) - 1, 1); 1063 1064 return 0; 1065 } 1066 1067 static int at91_ts_register(struct at91_adc_state *st, 1068 struct platform_device *pdev) 1069 { 1070 struct input_dev *input; 1071 struct iio_dev *idev = iio_priv_to_dev(st); 1072 int ret; 1073 1074 input = input_allocate_device(); 1075 if (!input) { 1076 dev_err(&idev->dev, "Failed to allocate TS device!\n"); 1077 return -ENOMEM; 1078 } 1079 1080 input->name = DRIVER_NAME; 1081 input->id.bustype = BUS_HOST; 1082 input->dev.parent = &pdev->dev; 1083 input->open = atmel_ts_open; 1084 input->close = atmel_ts_close; 1085 1086 __set_bit(EV_ABS, input->evbit); 1087 __set_bit(EV_KEY, input->evbit); 1088 __set_bit(BTN_TOUCH, input->keybit); 1089 if (st->caps->has_tsmr) { 1090 input_set_abs_params(input, ABS_X, 0, (1 << MAX_POS_BITS) - 1, 1091 0, 0); 1092 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_POS_BITS) - 1, 1093 0, 0); 1094 input_set_abs_params(input, ABS_PRESSURE, 0, 0xffffff, 0, 0); 1095 } else { 1096 if (st->touchscreen_type != ATMEL_ADC_TOUCHSCREEN_4WIRE) { 1097 dev_err(&pdev->dev, 1098 "This touchscreen controller only support 4 wires\n"); 1099 ret = -EINVAL; 1100 goto err; 1101 } 1102 1103 input_set_abs_params(input, ABS_X, 0, (1 << MAX_RLPOS_BITS) - 1, 1104 0, 0); 1105 input_set_abs_params(input, ABS_Y, 0, (1 << MAX_RLPOS_BITS) - 1, 1106 0, 0); 1107 } 1108 1109 st->ts_input = input; 1110 input_set_drvdata(input, st); 1111 1112 ret = input_register_device(input); 1113 if (ret) 1114 goto err; 1115 1116 return ret; 1117 1118 err: 1119 input_free_device(st->ts_input); 1120 return ret; 1121 } 1122 1123 static void at91_ts_unregister(struct at91_adc_state *st) 1124 { 1125 input_unregister_device(st->ts_input); 1126 } 1127 1128 static int at91_adc_probe(struct platform_device *pdev) 1129 { 1130 unsigned int prsc, mstrclk, ticks, adc_clk, adc_clk_khz, shtim; 1131 int ret; 1132 struct iio_dev *idev; 1133 struct at91_adc_state *st; 1134 struct resource *res; 1135 u32 reg; 1136 1137 idev = devm_iio_device_alloc(&pdev->dev, sizeof(struct at91_adc_state)); 1138 if (!idev) 1139 return -ENOMEM; 1140 1141 st = iio_priv(idev); 1142 1143 if (pdev->dev.of_node) 1144 ret = at91_adc_probe_dt(st, pdev); 1145 else 1146 ret = at91_adc_probe_pdata(st, pdev); 1147 1148 if (ret) { 1149 dev_err(&pdev->dev, "No platform data available.\n"); 1150 return -EINVAL; 1151 } 1152 1153 platform_set_drvdata(pdev, idev); 1154 1155 idev->dev.parent = &pdev->dev; 1156 idev->name = dev_name(&pdev->dev); 1157 idev->modes = INDIO_DIRECT_MODE; 1158 idev->info = &at91_adc_info; 1159 1160 st->irq = platform_get_irq(pdev, 0); 1161 if (st->irq < 0) { 1162 dev_err(&pdev->dev, "No IRQ ID is designated\n"); 1163 return -ENODEV; 1164 } 1165 1166 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1167 1168 st->reg_base = devm_ioremap_resource(&pdev->dev, res); 1169 if (IS_ERR(st->reg_base)) { 1170 return PTR_ERR(st->reg_base); 1171 } 1172 1173 /* 1174 * Disable all IRQs before setting up the handler 1175 */ 1176 at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_SWRST); 1177 at91_adc_writel(st, AT91_ADC_IDR, 0xFFFFFFFF); 1178 1179 if (st->caps->has_tsmr) 1180 ret = request_irq(st->irq, at91_adc_9x5_interrupt, 0, 1181 pdev->dev.driver->name, idev); 1182 else 1183 ret = request_irq(st->irq, at91_adc_rl_interrupt, 0, 1184 pdev->dev.driver->name, idev); 1185 if (ret) { 1186 dev_err(&pdev->dev, "Failed to allocate IRQ.\n"); 1187 return ret; 1188 } 1189 1190 st->clk = devm_clk_get(&pdev->dev, "adc_clk"); 1191 if (IS_ERR(st->clk)) { 1192 dev_err(&pdev->dev, "Failed to get the clock.\n"); 1193 ret = PTR_ERR(st->clk); 1194 goto error_free_irq; 1195 } 1196 1197 ret = clk_prepare_enable(st->clk); 1198 if (ret) { 1199 dev_err(&pdev->dev, 1200 "Could not prepare or enable the clock.\n"); 1201 goto error_free_irq; 1202 } 1203 1204 st->adc_clk = devm_clk_get(&pdev->dev, "adc_op_clk"); 1205 if (IS_ERR(st->adc_clk)) { 1206 dev_err(&pdev->dev, "Failed to get the ADC clock.\n"); 1207 ret = PTR_ERR(st->adc_clk); 1208 goto error_disable_clk; 1209 } 1210 1211 ret = clk_prepare_enable(st->adc_clk); 1212 if (ret) { 1213 dev_err(&pdev->dev, 1214 "Could not prepare or enable the ADC clock.\n"); 1215 goto error_disable_clk; 1216 } 1217 1218 /* 1219 * Prescaler rate computation using the formula from the Atmel's 1220 * datasheet : ADC Clock = MCK / ((Prescaler + 1) * 2), ADC Clock being 1221 * specified by the electrical characteristics of the board. 1222 */ 1223 mstrclk = clk_get_rate(st->clk); 1224 adc_clk = clk_get_rate(st->adc_clk); 1225 adc_clk_khz = adc_clk / 1000; 1226 1227 dev_dbg(&pdev->dev, "Master clock is set as: %d Hz, adc_clk should set as: %d Hz\n", 1228 mstrclk, adc_clk); 1229 1230 prsc = (mstrclk / (2 * adc_clk)) - 1; 1231 1232 if (!st->startup_time) { 1233 dev_err(&pdev->dev, "No startup time available.\n"); 1234 ret = -EINVAL; 1235 goto error_disable_adc_clk; 1236 } 1237 ticks = (*st->caps->calc_startup_ticks)(st->startup_time, adc_clk_khz); 1238 1239 /* 1240 * a minimal Sample and Hold Time is necessary for the ADC to guarantee 1241 * the best converted final value between two channels selection 1242 * The formula thus is : Sample and Hold Time = (shtim + 1) / ADCClock 1243 */ 1244 if (st->sample_hold_time > 0) 1245 shtim = round_up((st->sample_hold_time * adc_clk_khz / 1000) 1246 - 1, 1); 1247 else 1248 shtim = 0; 1249 1250 reg = AT91_ADC_PRESCAL_(prsc) & st->registers->mr_prescal_mask; 1251 reg |= AT91_ADC_STARTUP_(ticks) & st->registers->mr_startup_mask; 1252 if (st->low_res) 1253 reg |= AT91_ADC_LOWRES; 1254 if (st->sleep_mode) 1255 reg |= AT91_ADC_SLEEP; 1256 reg |= AT91_ADC_SHTIM_(shtim) & AT91_ADC_SHTIM; 1257 at91_adc_writel(st, AT91_ADC_MR, reg); 1258 1259 /* Setup the ADC channels available on the board */ 1260 ret = at91_adc_channel_init(idev); 1261 if (ret < 0) { 1262 dev_err(&pdev->dev, "Couldn't initialize the channels.\n"); 1263 goto error_disable_adc_clk; 1264 } 1265 1266 init_waitqueue_head(&st->wq_data_avail); 1267 mutex_init(&st->lock); 1268 1269 /* 1270 * Since touch screen will set trigger register as period trigger. So 1271 * when touch screen is enabled, then we have to disable hardware 1272 * trigger for classic adc. 1273 */ 1274 if (!st->touchscreen_type) { 1275 ret = at91_adc_buffer_init(idev); 1276 if (ret < 0) { 1277 dev_err(&pdev->dev, "Couldn't initialize the buffer.\n"); 1278 goto error_disable_adc_clk; 1279 } 1280 1281 ret = at91_adc_trigger_init(idev); 1282 if (ret < 0) { 1283 dev_err(&pdev->dev, "Couldn't setup the triggers.\n"); 1284 at91_adc_buffer_remove(idev); 1285 goto error_disable_adc_clk; 1286 } 1287 } else { 1288 ret = at91_ts_register(st, pdev); 1289 if (ret) 1290 goto error_disable_adc_clk; 1291 1292 at91_ts_hw_init(st, adc_clk_khz); 1293 } 1294 1295 ret = iio_device_register(idev); 1296 if (ret < 0) { 1297 dev_err(&pdev->dev, "Couldn't register the device.\n"); 1298 goto error_iio_device_register; 1299 } 1300 1301 return 0; 1302 1303 error_iio_device_register: 1304 if (!st->touchscreen_type) { 1305 at91_adc_trigger_remove(idev); 1306 at91_adc_buffer_remove(idev); 1307 } else { 1308 at91_ts_unregister(st); 1309 } 1310 error_disable_adc_clk: 1311 clk_disable_unprepare(st->adc_clk); 1312 error_disable_clk: 1313 clk_disable_unprepare(st->clk); 1314 error_free_irq: 1315 free_irq(st->irq, idev); 1316 return ret; 1317 } 1318 1319 static int at91_adc_remove(struct platform_device *pdev) 1320 { 1321 struct iio_dev *idev = platform_get_drvdata(pdev); 1322 struct at91_adc_state *st = iio_priv(idev); 1323 1324 iio_device_unregister(idev); 1325 if (!st->touchscreen_type) { 1326 at91_adc_trigger_remove(idev); 1327 at91_adc_buffer_remove(idev); 1328 } else { 1329 at91_ts_unregister(st); 1330 } 1331 clk_disable_unprepare(st->adc_clk); 1332 clk_disable_unprepare(st->clk); 1333 free_irq(st->irq, idev); 1334 1335 return 0; 1336 } 1337 1338 static struct at91_adc_caps at91sam9260_caps = { 1339 .calc_startup_ticks = calc_startup_ticks_9260, 1340 .num_channels = 4, 1341 .registers = { 1342 .channel_base = AT91_ADC_CHR(0), 1343 .drdy_mask = AT91_ADC_DRDY, 1344 .status_register = AT91_ADC_SR, 1345 .trigger_register = AT91_ADC_TRGR_9260, 1346 .mr_prescal_mask = AT91_ADC_PRESCAL_9260, 1347 .mr_startup_mask = AT91_ADC_STARTUP_9260, 1348 }, 1349 }; 1350 1351 static struct at91_adc_caps at91sam9rl_caps = { 1352 .has_ts = true, 1353 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */ 1354 .num_channels = 6, 1355 .registers = { 1356 .channel_base = AT91_ADC_CHR(0), 1357 .drdy_mask = AT91_ADC_DRDY, 1358 .status_register = AT91_ADC_SR, 1359 .trigger_register = AT91_ADC_TRGR_9G45, 1360 .mr_prescal_mask = AT91_ADC_PRESCAL_9260, 1361 .mr_startup_mask = AT91_ADC_STARTUP_9G45, 1362 }, 1363 }; 1364 1365 static struct at91_adc_caps at91sam9g45_caps = { 1366 .has_ts = true, 1367 .calc_startup_ticks = calc_startup_ticks_9260, /* same as 9260 */ 1368 .num_channels = 8, 1369 .registers = { 1370 .channel_base = AT91_ADC_CHR(0), 1371 .drdy_mask = AT91_ADC_DRDY, 1372 .status_register = AT91_ADC_SR, 1373 .trigger_register = AT91_ADC_TRGR_9G45, 1374 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45, 1375 .mr_startup_mask = AT91_ADC_STARTUP_9G45, 1376 }, 1377 }; 1378 1379 static struct at91_adc_caps at91sam9x5_caps = { 1380 .has_ts = true, 1381 .has_tsmr = true, 1382 .ts_filter_average = 3, 1383 .ts_pen_detect_sensitivity = 2, 1384 .calc_startup_ticks = calc_startup_ticks_9x5, 1385 .num_channels = 12, 1386 .registers = { 1387 .channel_base = AT91_ADC_CDR0_9X5, 1388 .drdy_mask = AT91_ADC_SR_DRDY_9X5, 1389 .status_register = AT91_ADC_SR_9X5, 1390 .trigger_register = AT91_ADC_TRGR_9X5, 1391 /* prescal mask is same as 9G45 */ 1392 .mr_prescal_mask = AT91_ADC_PRESCAL_9G45, 1393 .mr_startup_mask = AT91_ADC_STARTUP_9X5, 1394 }, 1395 }; 1396 1397 static const struct of_device_id at91_adc_dt_ids[] = { 1398 { .compatible = "atmel,at91sam9260-adc", .data = &at91sam9260_caps }, 1399 { .compatible = "atmel,at91sam9rl-adc", .data = &at91sam9rl_caps }, 1400 { .compatible = "atmel,at91sam9g45-adc", .data = &at91sam9g45_caps }, 1401 { .compatible = "atmel,at91sam9x5-adc", .data = &at91sam9x5_caps }, 1402 {}, 1403 }; 1404 MODULE_DEVICE_TABLE(of, at91_adc_dt_ids); 1405 1406 static const struct platform_device_id at91_adc_ids[] = { 1407 { 1408 .name = "at91sam9260-adc", 1409 .driver_data = (unsigned long)&at91sam9260_caps, 1410 }, { 1411 .name = "at91sam9rl-adc", 1412 .driver_data = (unsigned long)&at91sam9rl_caps, 1413 }, { 1414 .name = "at91sam9g45-adc", 1415 .driver_data = (unsigned long)&at91sam9g45_caps, 1416 }, { 1417 .name = "at91sam9x5-adc", 1418 .driver_data = (unsigned long)&at91sam9x5_caps, 1419 }, { 1420 /* terminator */ 1421 } 1422 }; 1423 MODULE_DEVICE_TABLE(platform, at91_adc_ids); 1424 1425 static struct platform_driver at91_adc_driver = { 1426 .probe = at91_adc_probe, 1427 .remove = at91_adc_remove, 1428 .id_table = at91_adc_ids, 1429 .driver = { 1430 .name = DRIVER_NAME, 1431 .of_match_table = of_match_ptr(at91_adc_dt_ids), 1432 }, 1433 }; 1434 1435 module_platform_driver(at91_adc_driver); 1436 1437 MODULE_LICENSE("GPL"); 1438 MODULE_DESCRIPTION("Atmel AT91 ADC Driver"); 1439 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); 1440