linux/drivers/mfd/ucb1x00-core.c
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   1/*
   2 *  linux/drivers/mfd/ucb1x00-core.c
   3 *
   4 *  Copyright (C) 2001 Russell King, All Rights Reserved.
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License.
   9 *
  10 *  The UCB1x00 core driver provides basic services for handling IO,
  11 *  the ADC, interrupts, and accessing registers.  It is designed
  12 *  such that everything goes through this layer, thereby providing
  13 *  a consistent locking methodology, as well as allowing the drivers
  14 *  to be used on other non-MCP-enabled hardware platforms.
  15 *
  16 *  Note that all locks are private to this file.  Nothing else may
  17 *  touch them.
  18 */
  19#include <linux/module.h>
  20#include <linux/kernel.h>
  21#include <linux/sched.h>
  22#include <linux/slab.h>
  23#include <linux/init.h>
  24#include <linux/errno.h>
  25#include <linux/interrupt.h>
  26#include <linux/irq.h>
  27#include <linux/device.h>
  28#include <linux/mutex.h>
  29#include <linux/mfd/ucb1x00.h>
  30#include <linux/pm.h>
  31#include <linux/gpio.h>
  32
  33static DEFINE_MUTEX(ucb1x00_mutex);
  34static LIST_HEAD(ucb1x00_drivers);
  35static LIST_HEAD(ucb1x00_devices);
  36
  37/**
  38 *      ucb1x00_io_set_dir - set IO direction
  39 *      @ucb: UCB1x00 structure describing chip
  40 *      @in:  bitfield of IO pins to be set as inputs
  41 *      @out: bitfield of IO pins to be set as outputs
  42 *
  43 *      Set the IO direction of the ten general purpose IO pins on
  44 *      the UCB1x00 chip.  The @in bitfield has priority over the
  45 *      @out bitfield, in that if you specify a pin as both input
  46 *      and output, it will end up as an input.
  47 *
  48 *      ucb1x00_enable must have been called to enable the comms
  49 *      before using this function.
  50 *
  51 *      This function takes a spinlock, disabling interrupts.
  52 */
  53void ucb1x00_io_set_dir(struct ucb1x00 *ucb, unsigned int in, unsigned int out)
  54{
  55        unsigned long flags;
  56
  57        spin_lock_irqsave(&ucb->io_lock, flags);
  58        ucb->io_dir |= out;
  59        ucb->io_dir &= ~in;
  60
  61        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
  62        spin_unlock_irqrestore(&ucb->io_lock, flags);
  63}
  64
  65/**
  66 *      ucb1x00_io_write - set or clear IO outputs
  67 *      @ucb:   UCB1x00 structure describing chip
  68 *      @set:   bitfield of IO pins to set to logic '1'
  69 *      @clear: bitfield of IO pins to set to logic '0'
  70 *
  71 *      Set the IO output state of the specified IO pins.  The value
  72 *      is retained if the pins are subsequently configured as inputs.
  73 *      The @clear bitfield has priority over the @set bitfield -
  74 *      outputs will be cleared.
  75 *
  76 *      ucb1x00_enable must have been called to enable the comms
  77 *      before using this function.
  78 *
  79 *      This function takes a spinlock, disabling interrupts.
  80 */
  81void ucb1x00_io_write(struct ucb1x00 *ucb, unsigned int set, unsigned int clear)
  82{
  83        unsigned long flags;
  84
  85        spin_lock_irqsave(&ucb->io_lock, flags);
  86        ucb->io_out |= set;
  87        ucb->io_out &= ~clear;
  88
  89        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
  90        spin_unlock_irqrestore(&ucb->io_lock, flags);
  91}
  92
  93/**
  94 *      ucb1x00_io_read - read the current state of the IO pins
  95 *      @ucb: UCB1x00 structure describing chip
  96 *
  97 *      Return a bitfield describing the logic state of the ten
  98 *      general purpose IO pins.
  99 *
 100 *      ucb1x00_enable must have been called to enable the comms
 101 *      before using this function.
 102 *
 103 *      This function does not take any mutexes or spinlocks.
 104 */
 105unsigned int ucb1x00_io_read(struct ucb1x00 *ucb)
 106{
 107        return ucb1x00_reg_read(ucb, UCB_IO_DATA);
 108}
 109
 110static void ucb1x00_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 111{
 112        struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
 113        unsigned long flags;
 114
 115        spin_lock_irqsave(&ucb->io_lock, flags);
 116        if (value)
 117                ucb->io_out |= 1 << offset;
 118        else
 119                ucb->io_out &= ~(1 << offset);
 120
 121        ucb1x00_enable(ucb);
 122        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 123        ucb1x00_disable(ucb);
 124        spin_unlock_irqrestore(&ucb->io_lock, flags);
 125}
 126
 127static int ucb1x00_gpio_get(struct gpio_chip *chip, unsigned offset)
 128{
 129        struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
 130        unsigned val;
 131
 132        ucb1x00_enable(ucb);
 133        val = ucb1x00_reg_read(ucb, UCB_IO_DATA);
 134        ucb1x00_disable(ucb);
 135
 136        return val & (1 << offset);
 137}
 138
 139static int ucb1x00_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 140{
 141        struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
 142        unsigned long flags;
 143
 144        spin_lock_irqsave(&ucb->io_lock, flags);
 145        ucb->io_dir &= ~(1 << offset);
 146        ucb1x00_enable(ucb);
 147        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 148        ucb1x00_disable(ucb);
 149        spin_unlock_irqrestore(&ucb->io_lock, flags);
 150
 151        return 0;
 152}
 153
 154static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
 155                , int value)
 156{
 157        struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
 158        unsigned long flags;
 159        unsigned old, mask = 1 << offset;
 160
 161        spin_lock_irqsave(&ucb->io_lock, flags);
 162        old = ucb->io_out;
 163        if (value)
 164                ucb->io_out |= mask;
 165        else
 166                ucb->io_out &= ~mask;
 167
 168        ucb1x00_enable(ucb);
 169        if (old != ucb->io_out)
 170                ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 171
 172        if (!(ucb->io_dir & mask)) {
 173                ucb->io_dir |= mask;
 174                ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 175        }
 176        ucb1x00_disable(ucb);
 177        spin_unlock_irqrestore(&ucb->io_lock, flags);
 178
 179        return 0;
 180}
 181
 182static int ucb1x00_to_irq(struct gpio_chip *chip, unsigned offset)
 183{
 184        struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);
 185
 186        return ucb->irq_base > 0 ? ucb->irq_base + offset : -ENXIO;
 187}
 188
 189/*
 190 * UCB1300 data sheet says we must:
 191 *  1. enable ADC       => 5us (including reference startup time)
 192 *  2. select input     => 51*tsibclk  => 4.3us
 193 *  3. start conversion => 102*tsibclk => 8.5us
 194 * (tsibclk = 1/11981000)
 195 * Period between SIB 128-bit frames = 10.7us
 196 */
 197
 198/**
 199 *      ucb1x00_adc_enable - enable the ADC converter
 200 *      @ucb: UCB1x00 structure describing chip
 201 *
 202 *      Enable the ucb1x00 and ADC converter on the UCB1x00 for use.
 203 *      Any code wishing to use the ADC converter must call this
 204 *      function prior to using it.
 205 *
 206 *      This function takes the ADC mutex to prevent two or more
 207 *      concurrent uses, and therefore may sleep.  As a result, it
 208 *      can only be called from process context, not interrupt
 209 *      context.
 210 *
 211 *      You should release the ADC as soon as possible using
 212 *      ucb1x00_adc_disable.
 213 */
 214void ucb1x00_adc_enable(struct ucb1x00 *ucb)
 215{
 216        mutex_lock(&ucb->adc_mutex);
 217
 218        ucb->adc_cr |= UCB_ADC_ENA;
 219
 220        ucb1x00_enable(ucb);
 221        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
 222}
 223
 224/**
 225 *      ucb1x00_adc_read - read the specified ADC channel
 226 *      @ucb: UCB1x00 structure describing chip
 227 *      @adc_channel: ADC channel mask
 228 *      @sync: wait for syncronisation pulse.
 229 *
 230 *      Start an ADC conversion and wait for the result.  Note that
 231 *      synchronised ADC conversions (via the ADCSYNC pin) must wait
 232 *      until the trigger is asserted and the conversion is finished.
 233 *
 234 *      This function currently spins waiting for the conversion to
 235 *      complete (2 frames max without sync).
 236 *
 237 *      If called for a synchronised ADC conversion, it may sleep
 238 *      with the ADC mutex held.
 239 */
 240unsigned int ucb1x00_adc_read(struct ucb1x00 *ucb, int adc_channel, int sync)
 241{
 242        unsigned int val;
 243
 244        if (sync)
 245                adc_channel |= UCB_ADC_SYNC_ENA;
 246
 247        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel);
 248        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr | adc_channel | UCB_ADC_START);
 249
 250        for (;;) {
 251                val = ucb1x00_reg_read(ucb, UCB_ADC_DATA);
 252                if (val & UCB_ADC_DAT_VAL)
 253                        break;
 254                /* yield to other processes */
 255                set_current_state(TASK_INTERRUPTIBLE);
 256                schedule_timeout(1);
 257        }
 258
 259        return UCB_ADC_DAT(val);
 260}
 261
 262/**
 263 *      ucb1x00_adc_disable - disable the ADC converter
 264 *      @ucb: UCB1x00 structure describing chip
 265 *
 266 *      Disable the ADC converter and release the ADC mutex.
 267 */
 268void ucb1x00_adc_disable(struct ucb1x00 *ucb)
 269{
 270        ucb->adc_cr &= ~UCB_ADC_ENA;
 271        ucb1x00_reg_write(ucb, UCB_ADC_CR, ucb->adc_cr);
 272        ucb1x00_disable(ucb);
 273
 274        mutex_unlock(&ucb->adc_mutex);
 275}
 276
 277/*
 278 * UCB1x00 Interrupt handling.
 279 *
 280 * The UCB1x00 can generate interrupts when the SIBCLK is stopped.
 281 * Since we need to read an internal register, we must re-enable
 282 * SIBCLK to talk to the chip.  We leave the clock running until
 283 * we have finished processing all interrupts from the chip.
 284 */
 285static void ucb1x00_irq(unsigned int irq, struct irq_desc *desc)
 286{
 287        struct ucb1x00 *ucb = irq_desc_get_handler_data(desc);
 288        unsigned int isr, i;
 289
 290        ucb1x00_enable(ucb);
 291        isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
 292        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
 293        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 294
 295        for (i = 0; i < 16 && isr; i++, isr >>= 1, irq++)
 296                if (isr & 1)
 297                        generic_handle_irq(ucb->irq_base + i);
 298        ucb1x00_disable(ucb);
 299}
 300
 301static void ucb1x00_irq_update(struct ucb1x00 *ucb, unsigned mask)
 302{
 303        ucb1x00_enable(ucb);
 304        if (ucb->irq_ris_enbl & mask)
 305                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 306                                  ucb->irq_mask);
 307        if (ucb->irq_fal_enbl & mask)
 308                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 309                                  ucb->irq_mask);
 310        ucb1x00_disable(ucb);
 311}
 312
 313static void ucb1x00_irq_noop(struct irq_data *data)
 314{
 315}
 316
 317static void ucb1x00_irq_mask(struct irq_data *data)
 318{
 319        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 320        unsigned mask = 1 << (data->irq - ucb->irq_base);
 321
 322        raw_spin_lock(&ucb->irq_lock);
 323        ucb->irq_mask &= ~mask;
 324        ucb1x00_irq_update(ucb, mask);
 325        raw_spin_unlock(&ucb->irq_lock);
 326}
 327
 328static void ucb1x00_irq_unmask(struct irq_data *data)
 329{
 330        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 331        unsigned mask = 1 << (data->irq - ucb->irq_base);
 332
 333        raw_spin_lock(&ucb->irq_lock);
 334        ucb->irq_mask |= mask;
 335        ucb1x00_irq_update(ucb, mask);
 336        raw_spin_unlock(&ucb->irq_lock);
 337}
 338
 339static int ucb1x00_irq_set_type(struct irq_data *data, unsigned int type)
 340{
 341        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 342        unsigned mask = 1 << (data->irq - ucb->irq_base);
 343
 344        raw_spin_lock(&ucb->irq_lock);
 345        if (type & IRQ_TYPE_EDGE_RISING)
 346                ucb->irq_ris_enbl |= mask;
 347        else
 348                ucb->irq_ris_enbl &= ~mask;
 349
 350        if (type & IRQ_TYPE_EDGE_FALLING)
 351                ucb->irq_fal_enbl |= mask;
 352        else
 353                ucb->irq_fal_enbl &= ~mask;
 354        if (ucb->irq_mask & mask) {
 355                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 356                                  ucb->irq_mask);
 357                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 358                                  ucb->irq_mask);
 359        }
 360        raw_spin_unlock(&ucb->irq_lock);
 361
 362        return 0;
 363}
 364
 365static int ucb1x00_irq_set_wake(struct irq_data *data, unsigned int on)
 366{
 367        struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
 368        struct ucb1x00_plat_data *pdata = ucb->mcp->attached_device.platform_data;
 369        unsigned mask = 1 << (data->irq - ucb->irq_base);
 370
 371        if (!pdata || !pdata->can_wakeup)
 372                return -EINVAL;
 373
 374        raw_spin_lock(&ucb->irq_lock);
 375        if (on)
 376                ucb->irq_wake |= mask;
 377        else
 378                ucb->irq_wake &= ~mask;
 379        raw_spin_unlock(&ucb->irq_lock);
 380
 381        return 0;
 382}
 383
 384static struct irq_chip ucb1x00_irqchip = {
 385        .name = "ucb1x00",
 386        .irq_ack = ucb1x00_irq_noop,
 387        .irq_mask = ucb1x00_irq_mask,
 388        .irq_unmask = ucb1x00_irq_unmask,
 389        .irq_set_type = ucb1x00_irq_set_type,
 390        .irq_set_wake = ucb1x00_irq_set_wake,
 391};
 392
 393static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
 394{
 395        struct ucb1x00_dev *dev;
 396        int ret = -ENOMEM;
 397
 398        dev = kmalloc(sizeof(struct ucb1x00_dev), GFP_KERNEL);
 399        if (dev) {
 400                dev->ucb = ucb;
 401                dev->drv = drv;
 402
 403                ret = drv->add(dev);
 404
 405                if (ret == 0) {
 406                        list_add_tail(&dev->dev_node, &ucb->devs);
 407                        list_add_tail(&dev->drv_node, &drv->devs);
 408                } else {
 409                        kfree(dev);
 410                }
 411        }
 412        return ret;
 413}
 414
 415static void ucb1x00_remove_dev(struct ucb1x00_dev *dev)
 416{
 417        dev->drv->remove(dev);
 418        list_del(&dev->dev_node);
 419        list_del(&dev->drv_node);
 420        kfree(dev);
 421}
 422
 423/*
 424 * Try to probe our interrupt, rather than relying on lots of
 425 * hard-coded machine dependencies.  For reference, the expected
 426 * IRQ mappings are:
 427 *
 428 *      Machine         Default IRQ
 429 *      adsbitsy        IRQ_GPCIN4
 430 *      cerf            IRQ_GPIO_UCB1200_IRQ
 431 *      flexanet        IRQ_GPIO_GUI
 432 *      freebird        IRQ_GPIO_FREEBIRD_UCB1300_IRQ
 433 *      graphicsclient  ADS_EXT_IRQ(8)
 434 *      graphicsmaster  ADS_EXT_IRQ(8)
 435 *      lart            LART_IRQ_UCB1200
 436 *      omnimeter       IRQ_GPIO23
 437 *      pfs168          IRQ_GPIO_UCB1300_IRQ
 438 *      simpad          IRQ_GPIO_UCB1300_IRQ
 439 *      shannon         SHANNON_IRQ_GPIO_IRQ_CODEC
 440 *      yopy            IRQ_GPIO_UCB1200_IRQ
 441 */
 442static int ucb1x00_detect_irq(struct ucb1x00 *ucb)
 443{
 444        unsigned long mask;
 445
 446        mask = probe_irq_on();
 447        if (!mask) {
 448                probe_irq_off(mask);
 449                return NO_IRQ;
 450        }
 451
 452        /*
 453         * Enable the ADC interrupt.
 454         */
 455        ucb1x00_reg_write(ucb, UCB_IE_RIS, UCB_IE_ADC);
 456        ucb1x00_reg_write(ucb, UCB_IE_FAL, UCB_IE_ADC);
 457        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
 458        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 459
 460        /*
 461         * Cause an ADC interrupt.
 462         */
 463        ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA);
 464        ucb1x00_reg_write(ucb, UCB_ADC_CR, UCB_ADC_ENA | UCB_ADC_START);
 465
 466        /*
 467         * Wait for the conversion to complete.
 468         */
 469        while ((ucb1x00_reg_read(ucb, UCB_ADC_DATA) & UCB_ADC_DAT_VAL) == 0);
 470        ucb1x00_reg_write(ucb, UCB_ADC_CR, 0);
 471
 472        /*
 473         * Disable and clear interrupt.
 474         */
 475        ucb1x00_reg_write(ucb, UCB_IE_RIS, 0);
 476        ucb1x00_reg_write(ucb, UCB_IE_FAL, 0);
 477        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0xffff);
 478        ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);
 479
 480        /*
 481         * Read triggered interrupt.
 482         */
 483        return probe_irq_off(mask);
 484}
 485
 486static void ucb1x00_release(struct device *dev)
 487{
 488        struct ucb1x00 *ucb = classdev_to_ucb1x00(dev);
 489        kfree(ucb);
 490}
 491
 492static struct class ucb1x00_class = {
 493        .name           = "ucb1x00",
 494        .dev_release    = ucb1x00_release,
 495};
 496
 497static int ucb1x00_probe(struct mcp *mcp)
 498{
 499        struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
 500        struct ucb1x00_driver *drv;
 501        struct ucb1x00 *ucb;
 502        unsigned id, i, irq_base;
 503        int ret = -ENODEV;
 504
 505        /* Tell the platform to deassert the UCB1x00 reset */
 506        if (pdata && pdata->reset)
 507                pdata->reset(UCB_RST_PROBE);
 508
 509        mcp_enable(mcp);
 510        id = mcp_reg_read(mcp, UCB_ID);
 511        mcp_disable(mcp);
 512
 513        if (id != UCB_ID_1200 && id != UCB_ID_1300 && id != UCB_ID_TC35143) {
 514                printk(KERN_WARNING "UCB1x00 ID not found: %04x\n", id);
 515                goto out;
 516        }
 517
 518        ucb = kzalloc(sizeof(struct ucb1x00), GFP_KERNEL);
 519        ret = -ENOMEM;
 520        if (!ucb)
 521                goto out;
 522
 523        device_initialize(&ucb->dev);
 524        ucb->dev.class = &ucb1x00_class;
 525        ucb->dev.parent = &mcp->attached_device;
 526        dev_set_name(&ucb->dev, "ucb1x00");
 527
 528        raw_spin_lock_init(&ucb->irq_lock);
 529        spin_lock_init(&ucb->io_lock);
 530        mutex_init(&ucb->adc_mutex);
 531
 532        ucb->id  = id;
 533        ucb->mcp = mcp;
 534
 535        ret = device_add(&ucb->dev);
 536        if (ret)
 537                goto err_dev_add;
 538
 539        ucb1x00_enable(ucb);
 540        ucb->irq = ucb1x00_detect_irq(ucb);
 541        ucb1x00_disable(ucb);
 542        if (ucb->irq == NO_IRQ) {
 543                dev_err(&ucb->dev, "IRQ probe failed\n");
 544                ret = -ENODEV;
 545                goto err_no_irq;
 546        }
 547
 548        ucb->gpio.base = -1;
 549        irq_base = pdata ? pdata->irq_base : 0;
 550        ucb->irq_base = irq_alloc_descs(-1, irq_base, 16, -1);
 551        if (ucb->irq_base < 0) {
 552                dev_err(&ucb->dev, "unable to allocate 16 irqs: %d\n",
 553                        ucb->irq_base);
 554                goto err_irq_alloc;
 555        }
 556
 557        for (i = 0; i < 16; i++) {
 558                unsigned irq = ucb->irq_base + i;
 559
 560                irq_set_chip_and_handler(irq, &ucb1x00_irqchip, handle_edge_irq);
 561                irq_set_chip_data(irq, ucb);
 562                set_irq_flags(irq, IRQF_VALID | IRQ_NOREQUEST);
 563        }
 564
 565        irq_set_irq_type(ucb->irq, IRQ_TYPE_EDGE_RISING);
 566        irq_set_handler_data(ucb->irq, ucb);
 567        irq_set_chained_handler(ucb->irq, ucb1x00_irq);
 568
 569        if (pdata && pdata->gpio_base) {
 570                ucb->gpio.label = dev_name(&ucb->dev);
 571                ucb->gpio.dev = &ucb->dev;
 572                ucb->gpio.owner = THIS_MODULE;
 573                ucb->gpio.base = pdata->gpio_base;
 574                ucb->gpio.ngpio = 10;
 575                ucb->gpio.set = ucb1x00_gpio_set;
 576                ucb->gpio.get = ucb1x00_gpio_get;
 577                ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
 578                ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
 579                ucb->gpio.to_irq = ucb1x00_to_irq;
 580                ret = gpiochip_add(&ucb->gpio);
 581                if (ret)
 582                        goto err_gpio_add;
 583        } else
 584                dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");
 585
 586        mcp_set_drvdata(mcp, ucb);
 587
 588        if (pdata)
 589                device_set_wakeup_capable(&ucb->dev, pdata->can_wakeup);
 590
 591        INIT_LIST_HEAD(&ucb->devs);
 592        mutex_lock(&ucb1x00_mutex);
 593        list_add_tail(&ucb->node, &ucb1x00_devices);
 594        list_for_each_entry(drv, &ucb1x00_drivers, node) {
 595                ucb1x00_add_dev(ucb, drv);
 596        }
 597        mutex_unlock(&ucb1x00_mutex);
 598
 599        return ret;
 600
 601 err_gpio_add:
 602        irq_set_chained_handler(ucb->irq, NULL);
 603 err_irq_alloc:
 604        if (ucb->irq_base > 0)
 605                irq_free_descs(ucb->irq_base, 16);
 606 err_no_irq:
 607        device_del(&ucb->dev);
 608 err_dev_add:
 609        put_device(&ucb->dev);
 610 out:
 611        if (pdata && pdata->reset)
 612                pdata->reset(UCB_RST_PROBE_FAIL);
 613        return ret;
 614}
 615
 616static void ucb1x00_remove(struct mcp *mcp)
 617{
 618        struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
 619        struct ucb1x00 *ucb = mcp_get_drvdata(mcp);
 620        struct list_head *l, *n;
 621        int ret;
 622
 623        mutex_lock(&ucb1x00_mutex);
 624        list_del(&ucb->node);
 625        list_for_each_safe(l, n, &ucb->devs) {
 626                struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, dev_node);
 627                ucb1x00_remove_dev(dev);
 628        }
 629        mutex_unlock(&ucb1x00_mutex);
 630
 631        if (ucb->gpio.base != -1) {
 632                ret = gpiochip_remove(&ucb->gpio);
 633                if (ret)
 634                        dev_err(&ucb->dev, "Can't remove gpio chip: %d\n", ret);
 635        }
 636
 637        irq_set_chained_handler(ucb->irq, NULL);
 638        irq_free_descs(ucb->irq_base, 16);
 639        device_unregister(&ucb->dev);
 640
 641        if (pdata && pdata->reset)
 642                pdata->reset(UCB_RST_REMOVE);
 643}
 644
 645int ucb1x00_register_driver(struct ucb1x00_driver *drv)
 646{
 647        struct ucb1x00 *ucb;
 648
 649        INIT_LIST_HEAD(&drv->devs);
 650        mutex_lock(&ucb1x00_mutex);
 651        list_add_tail(&drv->node, &ucb1x00_drivers);
 652        list_for_each_entry(ucb, &ucb1x00_devices, node) {
 653                ucb1x00_add_dev(ucb, drv);
 654        }
 655        mutex_unlock(&ucb1x00_mutex);
 656        return 0;
 657}
 658
 659void ucb1x00_unregister_driver(struct ucb1x00_driver *drv)
 660{
 661        struct list_head *n, *l;
 662
 663        mutex_lock(&ucb1x00_mutex);
 664        list_del(&drv->node);
 665        list_for_each_safe(l, n, &drv->devs) {
 666                struct ucb1x00_dev *dev = list_entry(l, struct ucb1x00_dev, drv_node);
 667                ucb1x00_remove_dev(dev);
 668        }
 669        mutex_unlock(&ucb1x00_mutex);
 670}
 671
 672static int ucb1x00_suspend(struct device *dev)
 673{
 674        struct ucb1x00_plat_data *pdata = dev->platform_data;
 675        struct ucb1x00 *ucb = dev_get_drvdata(dev);
 676        struct ucb1x00_dev *udev;
 677
 678        mutex_lock(&ucb1x00_mutex);
 679        list_for_each_entry(udev, &ucb->devs, dev_node) {
 680                if (udev->drv->suspend)
 681                        udev->drv->suspend(udev);
 682        }
 683        mutex_unlock(&ucb1x00_mutex);
 684
 685        if (ucb->irq_wake) {
 686                unsigned long flags;
 687
 688                raw_spin_lock_irqsave(&ucb->irq_lock, flags);
 689                ucb1x00_enable(ucb);
 690                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 691                                  ucb->irq_wake);
 692                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 693                                  ucb->irq_wake);
 694                ucb1x00_disable(ucb);
 695                raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
 696
 697                enable_irq_wake(ucb->irq);
 698        } else if (pdata && pdata->reset)
 699                pdata->reset(UCB_RST_SUSPEND);
 700
 701        return 0;
 702}
 703
 704static int ucb1x00_resume(struct device *dev)
 705{
 706        struct ucb1x00_plat_data *pdata = dev->platform_data;
 707        struct ucb1x00 *ucb = dev_get_drvdata(dev);
 708        struct ucb1x00_dev *udev;
 709
 710        if (!ucb->irq_wake && pdata && pdata->reset)
 711                pdata->reset(UCB_RST_RESUME);
 712
 713        ucb1x00_enable(ucb);
 714        ucb1x00_reg_write(ucb, UCB_IO_DATA, ucb->io_out);
 715        ucb1x00_reg_write(ucb, UCB_IO_DIR, ucb->io_dir);
 716
 717        if (ucb->irq_wake) {
 718                unsigned long flags;
 719
 720                raw_spin_lock_irqsave(&ucb->irq_lock, flags);
 721                ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
 722                                  ucb->irq_mask);
 723                ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
 724                                  ucb->irq_mask);
 725                raw_spin_unlock_irqrestore(&ucb->irq_lock, flags);
 726
 727                disable_irq_wake(ucb->irq);
 728        }
 729        ucb1x00_disable(ucb);
 730
 731        mutex_lock(&ucb1x00_mutex);
 732        list_for_each_entry(udev, &ucb->devs, dev_node) {
 733                if (udev->drv->resume)
 734                        udev->drv->resume(udev);
 735        }
 736        mutex_unlock(&ucb1x00_mutex);
 737        return 0;
 738}
 739
 740static const struct dev_pm_ops ucb1x00_pm_ops = {
 741        SET_SYSTEM_SLEEP_PM_OPS(ucb1x00_suspend, ucb1x00_resume)
 742};
 743
 744static struct mcp_driver ucb1x00_driver = {
 745        .drv            = {
 746                .name   = "ucb1x00",
 747                .owner  = THIS_MODULE,
 748                .pm     = &ucb1x00_pm_ops,
 749        },
 750        .probe          = ucb1x00_probe,
 751        .remove         = ucb1x00_remove,
 752};
 753
 754static int __init ucb1x00_init(void)
 755{
 756        int ret = class_register(&ucb1x00_class);
 757        if (ret == 0) {
 758                ret = mcp_driver_register(&ucb1x00_driver);
 759                if (ret)
 760                        class_unregister(&ucb1x00_class);
 761        }
 762        return ret;
 763}
 764
 765static void __exit ucb1x00_exit(void)
 766{
 767        mcp_driver_unregister(&ucb1x00_driver);
 768        class_unregister(&ucb1x00_class);
 769}
 770
 771module_init(ucb1x00_init);
 772module_exit(ucb1x00_exit);
 773
 774EXPORT_SYMBOL(ucb1x00_io_set_dir);
 775EXPORT_SYMBOL(ucb1x00_io_write);
 776EXPORT_SYMBOL(ucb1x00_io_read);
 777
 778EXPORT_SYMBOL(ucb1x00_adc_enable);
 779EXPORT_SYMBOL(ucb1x00_adc_read);
 780EXPORT_SYMBOL(ucb1x00_adc_disable);
 781
 782EXPORT_SYMBOL(ucb1x00_register_driver);
 783EXPORT_SYMBOL(ucb1x00_unregister_driver);
 784
 785MODULE_ALIAS("mcp:ucb1x00");
 786MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
 787MODULE_DESCRIPTION("UCB1x00 core driver");
 788MODULE_LICENSE("GPL");
 789