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