cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ucb1x00-core.c (19904B)


      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");