linux/drivers/mfd/ucb1x00-core.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/drivers/mfd/ucb1x00-core.c
   4 *
   5 *  Copyright (C) 2001 Russell King, All Rights Reserved.
   6 *
   7 *  The UCB1x00 core driver provides basic services for handling IO,
   8 *  the ADC, interrupts, and accessing registers.  It is designed
   9 *  such that everything goes through this layer, thereby providing
  10 *  a consistent locking methodology, as well as allowing the drivers
  11 *  to be used on other non-MCP-enabled hardware platforms.
  12 *
  13 *  Note that all locks are private to this file.  Nothing else may
  14 *  touch them.
  15 */
  16#include <linux/module.h>
  17#include <linux/kernel.h>
  18#include <linux/sched.h>
  19#include <linux/slab.h>
  20#include <linux/init.h>
  21#include <linux/errno.h>
  22#include <linux/interrupt.h>
  23#include <linux/irq.h>
  24#include <linux/device.h>
  25#include <linux/mutex.h>
  26#include <linux/mfd/ucb1x00.h>
  27#include <linux/pm.h>
  28#include <linux/gpio/driver.h>
  29
  30static DEFINE_MUTEX(ucb1x00_mutex);
  31static LIST_HEAD(ucb1x00_drivers);
  32static LIST_HEAD(ucb1x00_devices);
  33
  34/**
  35 *      ucb1x00_io_set_dir - set IO direction
  36 *      @ucb: UCB1x00 structure describing chip
  37 *      @in:  bitfield of IO pins to be set as inputs
  38 *      @out: bitfield of IO pins to be set as outputs
  39 *
  40 *      Set the IO direction of the ten general purpose IO pins on
  41 *      the UCB1x00 chip.  The @in bitfield has priority over the
  42 *      @out bitfield, in that if you specify a pin as both input
  43 *      and output, it will end up as an input.
  44 *
  45 *      ucb1x00_enable must have been called to enable the comms
  46 *      before using this function.
  47 *
  48 *      This function takes a spinlock, disabling interrupts.
  49 */
  50void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
  51{
  52        unsigned long flags;
  53
  54        spin_lock_irqsave(&ucb->io_lock, flags);
  55        ucb->io_dir |= out;
  56        ucb->io_dir &= ~in;
  57
  58        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  59        spin_unlock_irqrestore(&ucb->io_lock, flags);
  60}
  61
  62/**
  63 *      ucb1x00_io_write - set or clear IO outputs
  64 *      @ucb:   UCB1x00 structure describing chip
  65 *      @set:   bitfield of IO pins to set to logic '1'
  66 *      @clear: bitfield of IO pins to set to logic '0'
  67 *
  68 *      Set the IO output state of the specified IO pins.  The value
  69 *      is retained if the pins are subsequently configured as inputs.
  70 *      The @clear bitfield has priority over the @set bitfield -
  71 *      outputs will be cleared.
  72 *
  73 *      ucb1x00_enable must have been called to enable the comms
  74 *      before using this function.
  75 *
  76 *      This function takes a spinlock, disabling interrupts.
  77 */
  78void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
  79{
  80        unsigned long flags;
  81
  82        spin_lock_irqsave(&ucb->io_lock, flags);
  83        ucb->io_out |= set;
  84        ucb->io_out &= ~clear;
  85
  86        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
  87        spin_unlock_irqrestore(&ucb->io_lock, flags);
  88}
  89
  90/**
  91 *      ucb1x00_io_read - read the current state of the IO pins
  92 *      @ucb: UCB1x00 structure describing chip
  93 *
  94 *      Return a bitfield describing the logic state of the ten
  95 *      general purpose IO pins.
  96 *
  97 *      ucb1x00_enable must have been called to enable the comms
  98 *      before using this function.
  99 *
 100 *      This function does not take any mutexes or spinlocks.
 101 */
 102unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
 103{
 104        return ucb1x00_reg_read(ucb, UCB_IO_DATA);
 105}
 106
 107static void ucb1x00_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 108{
 109        struct ucb1x00 *ucb = gpiochip_get_data(chip);
 110        unsigned long flags;
 111
 112        spin_lock_irqsave(&ucb->io_lock, flags);
 113        if (value)
 114                ucb->io_out |= 1 << offset;
 115        else
 116                ucb->io_out &= ~(1 << offset);
 117
 118        ucb1x00_enable(ucb);
 119        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 120        ucb1x00_disable(ucb);
 121        spin_unlock_irqrestore(&ucb->io_lock, flags);
 122}
 123
 124static int ucb1x00_gpio_get(struct gpio_chip *chip, unsigned offset)
 125{
 126        struct ucb1x00 *ucb = gpiochip_get_data(chip);
 127        unsigned val;
 128
 129        ucb1x00_enable(ucb);
 130        val = ucb1x00_reg_read(ucb, UCB_IO_DATA);
 131        ucb1x00_disable(ucb);
 132
 133        return !!(val & (1 << offset));
 134}
 135
 136static int ucb1x00_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 137{
 138        struct ucb1x00 *ucb = gpiochip_get_data(chip);
 139        unsigned long flags;
 140
 141        spin_lock_irqsave(&ucb->io_lock, flags);
 142        ucb->io_dir &= ~(1 << offset);
 143        ucb1x00_enable(ucb);
 144        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 145        ucb1x00_disable(ucb);
 146        spin_unlock_irqrestore(&ucb->io_lock, flags);
 147
 148        return 0;
 149}
 150
 151static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
 152                , int value)
 153{
 154        struct ucb1x00 *ucb = gpiochip_get_data(chip);
 155        unsigned long flags;
 156        unsigned old, mask = 1 << offset;
 157
 158        spin_lock_irqsave(&ucb->io_lock, flags);
 159        old = ucb->io_out;
 160        if (value)
 161                ucb->io_out |= mask;
 162        else
 163                ucb->io_out &= ~mask;
 164
 165        ucb1x00_enable(ucb);
 166        if (old != ucb->io_out)
 167                ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 168
 169        if (!(ucb->io_dir & mask)) {
 170                ucb->io_dir |= mask;
 171                ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 172        }
 173        ucb1x00_disable(ucb);
 174        spin_unlock_irqrestore(&ucb->io_lock, flags);
 175
 176        return 0;
 177}
 178
 179static int ucb1x00_to_irq(struct gpio_chip *chip, unsigned offset)
 180{
 181        struct ucb1x00 *ucb = gpiochip_get_data(chip);
 182
 183        return ucb->irq_base > 0 ? ucb->irq_base + offset : -ENXIO;
 184}
 185
 186/*
 187 * UCB1300 data sheet says we must:
 188 *  1. enable ADC       => 5us (including reference startup time)
 189 *  2. select input     => 51*tsibclk  => 4.3us
 190 *  3. start conversion => 102*tsibclk => 8.5us
 191 * (tsibclk = 1/11981000)
 192 * Period between SIB 128-bit frames = 10.7us
 193 */
 194
 195/**
 196 *      ucb1x00_adc_enable - enable the ADC converter
 197 *      @ucb: UCB1x00 structure describing chip
 198 *
 199 *      Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
 200 *      Any code wishing to use the ADC converter must call this
 201 *      function prior to using it.
 202 *
 203 *      This function takes the ADC mutex to prevent two or more
 204 *      concurrent uses, and therefore may sleep.  As a result, it
 205 *      can only be called from process context, not interrupt
 206 *      context.
 207 *
 208 *      You should release the ADC as soon as possible using
 209 *      ucb1x00_adc_disable.
 210 */
 211void ucb1x00_adc_enable(struct ucb1x00 *ucb)
 212{
 213        mutex_lock(&ucb->adc_mutex);
 214
 215        ucb->adc_cr |= UCB_ADC_ENA;
 216
 217        ucb1x00_enable(ucb);
 218        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
 219}
 220
 221/**
 222 *      ucb1x00_adc_read - read the specified ADC channel
 223 *      @ucb: UCB1x00 structure describing chip
 224 *      @adc_channel: ADC channel mask
 225 *      @sync: wait for syncronisation pulse.
 226 *
 227 *      Start an ADC conversion and wait for the result.  Note that
 228 *      synchronised ADC conversions (via the ADCSYNC pin) must wait
 229 *      until the trigger is asserted and the conversion is finished.
 230 *
 231 *      This function currently spins waiting for the conversion to
 232 *      complete (2 frames max without sync).
 233 *
 234 *      If called for a synchronised ADC conversion, it may sleep
 235 *      with the ADC mutex held.
 236 */
 237unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
 238{
 239        unsigned int val;
 240
 241        if (sync)
 242                adc_channel |= UCB_ADC_SYNC_ENA;
 243
 244        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
 245        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
 246
 247        for (;;) {
 248                val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
 249                if (val & UCB_ADC_DAT_VAL)
 250                        break;
 251                /* yield to other processes */
 252                set_current_state(TASK_INTERRUPTIBLE);
 253                schedule_timeout(1);
 254        }
 255
 256        return UCB_ADC_DAT(val);
 257}
 258
 259/**
 260 *      ucb1x00_adc_disable - disable the ADC converter
 261 *      @ucb: UCB1x00 structure describing chip
 262 *
 263 *      Disable the ADC converter and release the ADC mutex.
 264 */
 265void ucb1x00_adc_disable(struct ucb1x00 *ucb)
 266{
 267        ucb->adc_cr &= ~UCB_ADC_ENA;
 268        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
 269        ucb1x00_disable(ucb);
 270
 271        mutex_unlock(&ucb->adc_mutex);
 272}
 273
 274/*
 275 * UCB1x00 Interrupt handling.
 276 *
 277 * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
 278 * Since we need to read an internal register, we must re-enable
 279 * SIBCLK to talk to the chip.  We leave the clock running until
 280 * we have finished processing all interrupts from the chip.
 281 */
 282static void ucb1x00_irq(struct irq_desc *desc)
 283{
 284        struct ucb1x00 *ucb = irq_desc_get_handler_data(desc);
 285        unsigned int isr, i;
 286
 287        ucb1x00_enable(ucb);
 288        isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
 289        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
 290        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 291
 292        for (i = 0; i < 16 && isr; i++, isr >>= 1)
 293                if (isr & 1)
 294                        generic_handle_irq(ucb->irq_base + i);
 295        ucb1x00_disable(ucb);
 296}
 297
 298static void ucb1x00_irq_update(struct ucb1x00 *ucb, unsigned mask)
 299{
 300        ucb1x00_enable(ucb);
 301        if (ucb->irq_ris_enbl & mask)
 302                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 303                                  ucb->irq_mask);
 304        if (ucb->irq_fal_enbl & mask)
 305                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 306                                  ucb->irq_mask);
 307        ucb1x00_disable(ucb);
 308}
 309
 310static void ucb1x00_irq_noop(struct irq_data *data)
 311{
 312}
 313
 314static void ucb1x00_irq_mask(struct irq_data *data)
 315{
 316        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 317        unsigned mask = 1 << (data->irq - ucb->irq_base);
 318
 319        raw_spin_lock(&ucb->irq_lock);
 320        ucb->irq_mask &= ~mask;
 321        ucb1x00_irq_update(ucb, mask);
 322        raw_spin_unlock(&ucb->irq_lock);
 323}
 324
 325static void ucb1x00_irq_unmask(struct irq_data *data)
 326{
 327        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 328        unsigned mask = 1 << (data->irq - ucb->irq_base);
 329
 330        raw_spin_lock(&ucb->irq_lock);
 331        ucb->irq_mask |= mask;
 332        ucb1x00_irq_update(ucb, mask);
 333        raw_spin_unlock(&ucb->irq_lock);
 334}
 335
 336static int ucb1x00_irq_set_type(struct irq_data *data, unsigned int type)
 337{
 338        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 339        unsigned mask = 1 << (data->irq - ucb->irq_base);
 340
 341        raw_spin_lock(&ucb->irq_lock);
 342        if (type & IRQ_TYPE_EDGE_RISING)
 343                ucb->irq_ris_enbl |= mask;
 344        else
 345                ucb->irq_ris_enbl &= ~mask;
 346
 347        if (type & IRQ_TYPE_EDGE_FALLING)
 348                ucb->irq_fal_enbl |= mask;
 349        else
 350                ucb->irq_fal_enbl &= ~mask;
 351        if (ucb->irq_mask & mask) {
 352                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 353                                  ucb->irq_mask);
 354                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 355                                  ucb->irq_mask);
 356        }
 357        raw_spin_unlock(&ucb->irq_lock);
 358
 359        return 0;
 360}
 361
 362static int ucb1x00_irq_set_wake(struct irq_data *data, unsigned int on)
 363{
 364        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 365        struct ucb1x00_plat_data *pdata = ucb->mcp->attached_device.platform_data;
 366        unsigned mask = 1 << (data->irq - ucb->irq_base);
 367
 368        if (!pdata || !pdata->can_wakeup)
 369                return -EINVAL;
 370
 371        raw_spin_lock(&ucb->irq_lock);
 372        if (on)
 373                ucb->irq_wake |= mask;
 374        else
 375                ucb->irq_wake &= ~mask;
 376        raw_spin_unlock(&ucb->irq_lock);
 377
 378        return 0;
 379}
 380
 381static struct irq_chip ucb1x00_irqchip = {
 382        .name = "ucb1x00",
 383        .irq_ack = ucb1x00_irq_noop,
 384        .irq_mask = ucb1x00_irq_mask,
 385        .irq_unmask = ucb1x00_irq_unmask,
 386        .irq_set_type = ucb1x00_irq_set_type,
 387        .irq_set_wake = ucb1x00_irq_set_wake,
 388};
 389
 390static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
 391{
 392        struct ucb1x00_dev *dev;
 393        int ret;
 394
 395        dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
 396        if (!dev)
 397                return -ENOMEM;
 398
 399        dev->ucb = ucb;
 400        dev->drv = drv;
 401
 402        ret = drv->add(dev);
 403        if (ret) {
 404                kfree(dev);
 405                return ret;
 406        }
 407
 408        list_add_tail(&dev->dev_node, &ucb->devs);
 409        list_add_tail(&dev->drv_node, &drv->devs);
 410
 411        return ret;
 412}
 413
 414static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
 415{
 416        dev->drv->remove(dev);
 417        list_del(&dev->dev_node);
 418        list_del(&dev->drv_node);
 419        kfree(dev);
 420}
 421
 422/*
 423 * Try to probe our interrupt, rather than relying on lots of
 424 * hard-coded machine dependencies.  For reference, the expected
 425 * IRQ mappings are:
 426 *
 427 *      Machine         Default IRQ
 428 *      adsbitsy        IRQ_GPCIN4
 429 *      cerf            IRQ_GPIO_UCB1200_IRQ
 430 *      flexanet        IRQ_GPIO_GUI
 431 *      freebird        IRQ_GPIO_FREEBIRD_UCB1300_IRQ
 432 *      graphicsclient  ADS_EXT_IRQ(8)
 433 *      graphicsmaster  ADS_EXT_IRQ(8)
 434 *      lart            LART_IRQ_UCB1200
 435 *      omnimeter       IRQ_GPIO23
 436 *      pfs168          IRQ_GPIO_UCB1300_IRQ
 437 *      simpad          IRQ_GPIO_UCB1300_IRQ
 438 *      shannon         SHANNON_IRQ_GPIO_IRQ_CODEC
 439 *      yopy            IRQ_GPIO_UCB1200_IRQ
 440 */
 441static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
 442{
 443        unsigned long mask;
 444
 445        mask = probe_irq_on();
 446
 447        /*
 448         * Enable the ADC interrupt.
 449         */
 450        ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
 451        ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
 452        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
 453        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 454
 455        /*
 456         * Cause an ADC interrupt.
 457         */
 458        ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
 459        ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
 460
 461        /*
 462         * Wait for the conversion to complete.
 463         */
 464        while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
 465        ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
 466
 467        /*
 468         * Disable and clear interrupt.
 469         */
 470        ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
 471        ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
 472        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
 473        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 474
 475        /*
 476         * Read triggered interrupt.
 477         */
 478        return probe_irq_off(mask);
 479}
 480
 481static void ucb1x00_release(struct device *dev)
 482{
 483        struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
 484        kfree(ucb);
 485}
 486
 487static struct class ucb1x00_class = {
 488        .name           = "ucb1x00",
 489        .dev_release    = ucb1x00_release,
 490};
 491
 492static int ucb1x00_probe(struct mcp *mcp)
 493{
 494        struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
 495        struct ucb1x00_driver *drv;
 496        struct ucb1x00 *ucb;
 497        unsigned id, i, irq_base;
 498        int ret = -ENODEV;
 499
 500        /* Tell the platform to deassert the UCB1x00 reset */
 501        if (pdata && pdata->reset)
 502                pdata->reset(UCB_RST_PROBE);
 503
 504        mcp_enable(mcp);
 505        id = mcp_reg_read(mcp, UCB_ID);
 506        mcp_disable(mcp);
 507
 508        if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
 509                printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
 510                goto out;
 511        }
 512
 513        ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
 514        ret = -ENOMEM;
 515        if (!ucb)
 516                goto out;
 517
 518        device_initialize(&ucb->dev);
 519        ucb->dev.class = &ucb1x00_class;
 520        ucb->dev.parent = &mcp->attached_device;
 521        dev_set_name(&ucb->dev, "ucb1x00");
 522
 523        raw_spin_lock_init(&ucb->irq_lock);
 524        spin_lock_init(&ucb->io_lock);
 525        mutex_init(&ucb->adc_mutex);
 526
 527        ucb->id  = id;
 528        ucb->mcp = mcp;
 529
 530        ret = device_add(&ucb->dev);
 531        if (ret)
 532                goto err_dev_add;
 533
 534        ucb1x00_enable(ucb);
 535        ucb->irq = ucb1x00_detect_irq(ucb);
 536        ucb1x00_disable(ucb);
 537        if (!ucb->irq) {
 538                dev_err(&ucb->dev, "IRQ probe failed\n");
 539                ret = -ENODEV;
 540                goto err_no_irq;
 541        }
 542
 543        ucb->gpio.base = -1;
 544        irq_base = pdata ? pdata->irq_base : 0;
 545        ucb->irq_base = irq_alloc_descs(-1, irq_base, 16, -1);
 546        if (ucb->irq_base < 0) {
 547                dev_err(&ucb->dev, "unable to allocate 16 irqs: %d\n",
 548                        ucb->irq_base);
 549                ret = ucb->irq_base;
 550                goto err_irq_alloc;
 551        }
 552
 553        for (i = 0; i < 16; i++) {
 554                unsigned irq = ucb->irq_base + i;
 555
 556                irq_set_chip_and_handler(irq, &ucb1x00_irqchip, handle_edge_irq);
 557                irq_set_chip_data(irq, ucb);
 558                irq_clear_status_flags(irq, IRQ_NOREQUEST);
 559        }
 560
 561        irq_set_irq_type(ucb->irq, IRQ_TYPE_EDGE_RISING);
 562        irq_set_chained_handler_and_data(ucb->irq, ucb1x00_irq, ucb);
 563
 564        if (pdata && pdata->gpio_base) {
 565                ucb->gpio.label = dev_name(&ucb->dev);
 566                ucb->gpio.parent = &ucb->dev;
 567                ucb->gpio.owner = THIS_MODULE;
 568                ucb->gpio.base = pdata->gpio_base;
 569                ucb->gpio.ngpio = 10;
 570                ucb->gpio.set = ucb1x00_gpio_set;
 571                ucb->gpio.get = ucb1x00_gpio_get;
 572                ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
 573                ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
 574                ucb->gpio.to_irq = ucb1x00_to_irq;
 575                ret = gpiochip_add_data(&ucb->gpio, ucb);
 576                if (ret)
 577                        goto err_gpio_add;
 578        } else
 579                dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");
 580
 581        mcp_set_drvdata(mcp, ucb);
 582
 583        if (pdata)
 584                device_set_wakeup_capable(&ucb->dev, pdata->can_wakeup);
 585
 586        INIT_LIST_HEAD(&ucb->devs);
 587        mutex_lock(&ucb1x00_mutex);
 588        list_add_tail(&ucb->node, &ucb1x00_devices);
 589        list_for_each_entry(drv, &ucb1x00_drivers, node) {
 590                ucb1x00_add_dev(ucb, drv);
 591        }
 592        mutex_unlock(&ucb1x00_mutex);
 593
 594        return ret;
 595
 596 err_gpio_add:
 597        irq_set_chained_handler(ucb->irq, NULL);
 598 err_irq_alloc:
 599        if (ucb->irq_base > 0)
 600                irq_free_descs(ucb->irq_base, 16);
 601 err_no_irq:
 602        device_del(&ucb->dev);
 603 err_dev_add:
 604        put_device(&ucb->dev);
 605 out:
 606        if (pdata && pdata->reset)
 607                pdata->reset(UCB_RST_PROBE_FAIL);
 608        return ret;
 609}
 610
 611static void ucb1x00_remove(struct mcp *mcp)
 612{
 613        struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
 614        struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
 615        struct list_head *l, *n;
 616
 617        mutex_lock(&ucb1x00_mutex);
 618        list_del(&ucb->node);
 619        list_for_each_safe(l, n, &ucb->devs) {
 620                struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
 621                ucb1x00_remove_dev(dev);
 622        }
 623        mutex_unlock(&ucb1x00_mutex);
 624
 625        if (ucb->gpio.base != -1)
 626                gpiochip_remove(&ucb->gpio);
 627
 628        irq_set_chained_handler(ucb->irq, NULL);
 629        irq_free_descs(ucb->irq_base, 16);
 630        device_unregister(&ucb->dev);
 631
 632        if (pdata && pdata->reset)
 633                pdata->reset(UCB_RST_REMOVE);
 634}
 635
 636int ucb1x00_register_driver(struct ucb1x00_driver *drv)
 637{
 638        struct ucb1x00 *ucb;
 639
 640        INIT_LIST_HEAD(&drv->devs);
 641        mutex_lock(&ucb1x00_mutex);
 642        list_add_tail(&drv->node, &ucb1x00_drivers);
 643        list_for_each_entry(ucb, &ucb1x00_devices, node) {
 644                ucb1x00_add_dev(ucb, drv);
 645        }
 646        mutex_unlock(&ucb1x00_mutex);
 647        return 0;
 648}
 649
 650void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
 651{
 652        struct list_head *n, *l;
 653
 654        mutex_lock(&ucb1x00_mutex);
 655        list_del(&drv->node);
 656        list_for_each_safe(l, n, &drv->devs) {
 657                struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
 658                ucb1x00_remove_dev(dev);
 659        }
 660        mutex_unlock(&ucb1x00_mutex);
 661}
 662
 663#ifdef CONFIG_PM_SLEEP
 664static int ucb1x00_suspend(struct device *dev)
 665{
 666        struct ucb1x00_plat_data *pdata = dev_get_platdata(dev);
 667        struct ucb1x00 *ucb = dev_get_drvdata(dev);
 668        struct ucb1x00_dev *udev;
 669
 670        mutex_lock(&ucb1x00_mutex);
 671        list_for_each_entry(udev, &ucb->devs, dev_node) {
 672                if (udev->drv->suspend)
 673                        udev->drv->suspend(udev);
 674        }
 675        mutex_unlock(&ucb1x00_mutex);
 676
 677        if (ucb->irq_wake) {
 678                unsigned long flags;
 679
 680                raw_spin_lock_irqsave(&ucb->irq_lock, flags);
 681                ucb1x00_enable(ucb);
 682                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 683                                  ucb->irq_wake);
 684                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 685                                  ucb->irq_wake);
 686                ucb1x00_disable(ucb);
 687                raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
 688
 689                enable_irq_wake(ucb->irq);
 690        } else if (pdata && pdata->reset)
 691                pdata->reset(UCB_RST_SUSPEND);
 692
 693        return 0;
 694}
 695
 696static int ucb1x00_resume(struct device *dev)
 697{
 698        struct ucb1x00_plat_data *pdata = dev_get_platdata(dev);
 699        struct ucb1x00 *ucb = dev_get_drvdata(dev);
 700        struct ucb1x00_dev *udev;
 701
 702        if (!ucb->irq_wake && pdata && pdata->reset)
 703                pdata->reset(UCB_RST_RESUME);
 704
 705        ucb1x00_enable(ucb);
 706        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 707        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 708
 709        if (ucb->irq_wake) {
 710                unsigned long flags;
 711
 712                raw_spin_lock_irqsave(&ucb->irq_lock, flags);
 713                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 714                                  ucb->irq_mask);
 715                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 716                                  ucb->irq_mask);
 717                raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
 718
 719                disable_irq_wake(ucb->irq);
 720        }
 721        ucb1x00_disable(ucb);
 722
 723        mutex_lock(&ucb1x00_mutex);
 724        list_for_each_entry(udev, &ucb->devs, dev_node) {
 725                if (udev->drv->resume)
 726                        udev->drv->resume(udev);
 727        }
 728        mutex_unlock(&ucb1x00_mutex);
 729        return 0;
 730}
 731#endif
 732
 733static SIMPLE_DEV_PM_OPS(ucb1x00_pm_ops, ucb1x00_suspend, ucb1x00_resume);
 734
 735static struct mcp_driver ucb1x00_driver = {
 736        .drv            = {
 737                .name   = "ucb1x00",
 738                .owner  = THIS_MODULE,
 739                .pm     = &ucb1x00_pm_ops,
 740        },
 741        .probe          = ucb1x00_probe,
 742        .remove         = ucb1x00_remove,
 743};
 744
 745static int __init ucb1x00_init(void)
 746{
 747        int ret = class_register(&ucb1x00_class);
 748        if (ret == 0) {
 749                ret = mcp_driver_register(&ucb1x00_driver);
 750                if (ret)
 751                        class_unregister(&ucb1x00_class);
 752        }
 753        return ret;
 754}
 755
 756static void __exit ucb1x00_exit(void)
 757{
 758        mcp_driver_unregister(&ucb1x00_driver);
 759        class_unregister(&ucb1x00_class);
 760}
 761
 762module_init(ucb1x00_init);
 763module_exit(ucb1x00_exit);
 764
 765EXPORT_SYMBOL(ucb1x00_io_set_dir);
 766EXPORT_SYMBOL(ucb1x00_io_write);
 767EXPORT_SYMBOL(ucb1x00_io_read);
 768
 769EXPORT_SYMBOL(ucb1x00_adc_enable);
 770EXPORT_SYMBOL(ucb1x00_adc_read);
 771EXPORT_SYMBOL(ucb1x00_adc_disable);
 772
 773EXPORT_SYMBOL(ucb1x00_register_driver);
 774EXPORT_SYMBOL(ucb1x00_unregister_driver);
 775
 776MODULE_ALIAS("mcp:ucb1x00");
 777MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 778MODULE_DESCRIPTION("UCB1x00 core driver");
 779MODULE_LICENSE("GPL");
 780