linux/drivers/input/touchscreen/wm97xx-core.c

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/*
* wm97xx-core.c -- Touch screen driver core for Wolfson WM9705, WM9712
* and WM9713 AC97 Codecs.
*
* Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
* Author: Liam Girdwood
* liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com
* Parts Copyright : Ian Molton <spyro@f2s.com>
* Andrew Zabolotny <zap@homelink.ru>
* Russell King <rmk@arm.linux.org.uk>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* Notes:
*
* Features:
* - supports WM9705, WM9712, WM9713
* - polling mode
* - continuous mode (arch-dependent)
* - adjustable rpu/dpp settings
* - adjustable pressure current
* - adjustable sample settle delay
* - 4 and 5 wire touchscreens (5 wire is WM9712 only)
* - pen down detection
* - battery monitor
* - sample AUX adcs
* - power management
* - codec GPIO
* - codec event notification
* Todo
* - Support for async sampling control for noisy LCDs.
*
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/proc_fs.h>
#include <linux/pm.h>
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/workqueue.h>
#include <linux/wm97xx.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#define TS_NAME "wm97xx"
#define WM_CORE_VERSION "1.00"
#define DEFAULT_PRESSURE 0xb0c0
/*
* Touchscreen absolute values
*
* These parameters are used to help the input layer discard out of
* range readings and reduce jitter etc.
*
* o min, max:- indicate the min and max values your touch screen returns
* o fuzz:- use a higher number to reduce jitter
*
* The default values correspond to Mainstone II in QVGA mode
*
* Please read
* Documentation/input/input-programming.txt for more details.
*/
static int abs_x[3] = {350, 3900, 5};
module_param_array(abs_x, int, NULL, 0);
MODULE_PARM_DESC(abs_x, "Touchscreen absolute X min, max, fuzz");
static int abs_y[3] = {320, 3750, 40};
module_param_array(abs_y, int, NULL, 0);
MODULE_PARM_DESC(abs_y, "Touchscreen absolute Y min, max, fuzz");
static int abs_p[3] = {0, 150, 4};
module_param_array(abs_p, int, NULL, 0);
MODULE_PARM_DESC(abs_p, "Touchscreen absolute Pressure min, max, fuzz");
/*
* wm97xx IO access, all IO locking done by AC97 layer
*/
int wm97xx_reg_read(struct wm97xx *wm, u16 reg)
{
if (wm->ac97)
return wm->ac97->bus->ops->read(wm->ac97, reg);
else
return -1;
}
EXPORT_SYMBOL_GPL(wm97xx_reg_read);
void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val)
{
/* cache digitiser registers */
if (reg >= AC97_WM9713_DIG1 && reg <= AC97_WM9713_DIG3)
wm->dig[(reg - AC97_WM9713_DIG1) >> 1] = val;
/* cache gpio regs */
if (reg >= AC97_GPIO_CFG && reg <= AC97_MISC_AFE)
wm->gpio[(reg - AC97_GPIO_CFG) >> 1] = val;
/* wm9713 irq reg */
if (reg == 0x5a)
wm->misc = val;
if (wm->ac97)
wm->ac97->bus->ops->write(wm->ac97, reg, val);
}
EXPORT_SYMBOL_GPL(wm97xx_reg_write);
/**
* wm97xx_read_aux_adc - Read the aux adc.
* @wm: wm97xx device.
* @adcsel: codec ADC to be read
*
* Reads the selected AUX ADC.
*/
int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel)
{
int power_adc = 0, auxval;
u16 power = 0;
/* get codec */
mutex_lock(&wm->codec_mutex);
/* When the touchscreen is not in use, we may have to power up
* the AUX ADC before we can use sample the AUX inputs->
*/
if (wm->id == WM9713_ID2 &&
(power = wm97xx_reg_read(wm, AC97_EXTENDED_MID)) & 0x8000) {
power_adc = 1;
wm97xx_reg_write(wm, AC97_EXTENDED_MID, power & 0x7fff);
}
/* Prepare the codec for AUX reading */
wm->codec->aux_prepare(wm);
/* Turn polling mode on to read AUX ADC */
wm->pen_probably_down = 1;
wm->codec->poll_sample(wm, adcsel, &auxval);
if (power_adc)
wm97xx_reg_write(wm, AC97_EXTENDED_MID, power | 0x8000);
wm->codec->dig_restore(wm);
wm->pen_probably_down = 0;
mutex_unlock(&wm->codec_mutex);
return auxval & 0xfff;
}
EXPORT_SYMBOL_GPL(wm97xx_read_aux_adc);
/**
* wm97xx_get_gpio - Get the status of a codec GPIO.
* @wm: wm97xx device.
* @gpio: gpio
*
* Get the status of a codec GPIO pin
*/
enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio)
{
u16 status;
enum wm97xx_gpio_status ret;
mutex_lock(&wm->codec_mutex);
status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
if (status & gpio)
ret = WM97XX_GPIO_HIGH;
else
ret = WM97XX_GPIO_LOW;
mutex_unlock(&wm->codec_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(wm97xx_get_gpio);
/**
* wm97xx_set_gpio - Set the status of a codec GPIO.
* @wm: wm97xx device.
* @gpio: gpio
*
*
* Set the status of a codec GPIO pin
*/
void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
enum wm97xx_gpio_status status)
{
u16 reg;
mutex_lock(&wm->codec_mutex);
reg = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
if (status & WM97XX_GPIO_HIGH)
reg |= gpio;
else
reg &= ~gpio;
if (wm->id == WM9712_ID2)
wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg << 1);
else
wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg);
mutex_unlock(&wm->codec_mutex);
}
EXPORT_SYMBOL_GPL(wm97xx_set_gpio);
/*
* Codec GPIO pin configuration, this sets pin direction, polarity,
* stickyness and wake up.
*/
void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
enum wm97xx_gpio_pol pol, enum wm97xx_gpio_sticky sticky,
enum wm97xx_gpio_wake wake)
{
u16 reg;
mutex_lock(&wm->codec_mutex);
reg = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
if (pol == WM97XX_GPIO_POL_HIGH)
reg |= gpio;
else
reg &= ~gpio;
wm97xx_reg_write(wm, AC97_GPIO_POLARITY, reg);
reg = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
if (sticky == WM97XX_GPIO_STICKY)
reg |= gpio;
else
reg &= ~gpio;
wm97xx_reg_write(wm, AC97_GPIO_STICKY, reg);
reg = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
if (wake == WM97XX_GPIO_WAKE)
reg |= gpio;
else
reg &= ~gpio;
wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, reg);
reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
if (dir == WM97XX_GPIO_IN)
reg |= gpio;
else
reg &= ~gpio;
wm97xx_reg_write(wm, AC97_GPIO_CFG, reg);
mutex_unlock(&wm->codec_mutex);
}
EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
/*
* Handle a pen down interrupt.
*/
static void wm97xx_pen_irq_worker(struct work_struct *work)
{
struct wm97xx *wm = container_of(work, struct wm97xx, pen_event_work);
int pen_was_down = wm->pen_is_down;
/* do we need to enable the touch panel reader */
if (wm->id == WM9705_ID2) {
if (wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD) &
WM97XX_PEN_DOWN)
wm->pen_is_down = 1;
else
wm->pen_is_down = 0;
} else {
u16 status, pol;
mutex_lock(&wm->codec_mutex);
status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
pol = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
if (WM97XX_GPIO_13 & pol & status) {
wm->pen_is_down = 1;
wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol &
~WM97XX_GPIO_13);
} else {
wm->pen_is_down = 0;
wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol |
WM97XX_GPIO_13);
}
if (wm->id == WM9712_ID2)
wm97xx_reg_write(wm, AC97_GPIO_STATUS, (status &
~WM97XX_GPIO_13) << 1);
else
wm97xx_reg_write(wm, AC97_GPIO_STATUS, status &
~WM97XX_GPIO_13);
mutex_unlock(&wm->codec_mutex);
}
/* If the system is not using continuous mode or it provides a
* pen down operation then we need to schedule polls while the
* pen is down. Otherwise the machine driver is responsible
* for scheduling reads.
*/
if (!wm->mach_ops->acc_enabled || wm->mach_ops->acc_pen_down) {
if (wm->pen_is_down && !pen_was_down) {
/* Data is not availiable immediately on pen down */
queue_delayed_work(wm->ts_workq, &wm->ts_reader, 1);
}
/* Let ts_reader report the pen up for debounce. */
if (!wm->pen_is_down && pen_was_down)
wm->pen_is_down = 1;
}
if (!wm->pen_is_down && wm->mach_ops->acc_enabled)
wm->mach_ops->acc_pen_up(wm);
wm->mach_ops->irq_enable(wm, 1);
}
/*
* Codec PENDOWN irq handler
*
* We have to disable the codec interrupt in the handler because it
* can take upto 1ms to clear the interrupt source. We schedule a task
* in a work queue to do the actual interaction with the chip (it
* doesn't matter if we end up reenqueing it before it is executed
* since we don't touch the chip until it has run). The interrupt is
* then enabled again in the slow handler when the source has been
* cleared.
*/
static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
{
struct wm97xx *wm = dev_id;
wm->mach_ops->irq_enable(wm, 0);
queue_work(wm->ts_workq, &wm->pen_event_work);
return IRQ_HANDLED;
}
/*
* initialise pen IRQ handler and workqueue
*/
static int wm97xx_init_pen_irq(struct wm97xx *wm)
{
u16 reg;
/* If an interrupt is supplied an IRQ enable operation must also be
* provided. */
BUG_ON(!wm->mach_ops->irq_enable);
if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
"wm97xx-pen", wm)) {
dev_err(wm->dev,
"Failed to register pen down interrupt, polling");
wm->pen_irq = 0;
return -EINVAL;
}
/* Configure GPIO as interrupt source on WM971x */
if (wm->id != WM9705_ID2) {
BUG_ON(!wm->mach_ops->irq_gpio);
reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
wm97xx_reg_write(wm, AC97_MISC_AFE,
reg & ~(wm->mach_ops->irq_gpio));
reg = wm97xx_reg_read(wm, 0x5a);
wm97xx_reg_write(wm, 0x5a, reg & ~0x0001);
}
return 0;
}
static int wm97xx_read_samples(struct wm97xx *wm)
{
struct wm97xx_data data;
int rc;
mutex_lock(&wm->codec_mutex);
if (wm->mach_ops && wm->mach_ops->acc_enabled)
rc = wm->mach_ops->acc_pen_down(wm);
else
rc = wm->codec->poll_touch(wm, &data);
if (rc & RC_PENUP) {
if (wm->pen_is_down) {
wm->pen_is_down = 0;
dev_dbg(wm->dev, "pen up\n");
input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
input_sync(wm->input_dev);
} else if (!(rc & RC_AGAIN)) {
/* We need high frequency updates only while
* pen is down, the user never will be able to
* touch screen faster than a few times per
* second... On the other hand, when the user
* is actively working with the touchscreen we
* don't want to lose the quick response. So we
* will slowly increase sleep time after the
* pen is up and quicky restore it to ~one task
* switch when pen is down again.
*/
if (wm->ts_reader_interval < HZ / 10)
wm->ts_reader_interval++;
}
} else if (rc & RC_VALID) {
dev_dbg(wm->dev,
"pen down: x=%x:%d, y=%x:%d, pressure=%x:%d\n",
data.x >> 12, data.x & 0xfff, data.y >> 12,
data.y & 0xfff, data.p >> 12, data.p & 0xfff);
input_report_abs(wm->input_dev, ABS_X, data.x & 0xfff);
input_report_abs(wm->input_dev, ABS_Y, data.y & 0xfff);
input_report_abs(wm->input_dev, ABS_PRESSURE, data.p & 0xfff);
input_sync(wm->input_dev);
wm->pen_is_down = 1;
wm->ts_reader_interval = wm->ts_reader_min_interval;
} else if (rc & RC_PENDOWN) {
dev_dbg(wm->dev, "pen down\n");
wm->pen_is_down = 1;
wm->ts_reader_interval = wm->ts_reader_min_interval;
}
mutex_unlock(&wm->codec_mutex);
return rc;
}
/*
* The touchscreen sample reader.
*/
static void wm97xx_ts_reader(struct work_struct *work)
{
int rc;
struct wm97xx *wm = container_of(work, struct wm97xx, ts_reader.work);
BUG_ON(!wm->codec);
do {
rc = wm97xx_read_samples(wm);
} while (rc & RC_AGAIN);
if (wm->pen_is_down || !wm->pen_irq)
queue_delayed_work(wm->ts_workq, &wm->ts_reader,
wm->ts_reader_interval);
}
/**
* wm97xx_ts_input_open - Open the touch screen input device.
* @idev: Input device to be opened.
*
* Called by the input sub system to open a wm97xx touchscreen device.
* Starts the touchscreen thread and touch digitiser.
*/
static int wm97xx_ts_input_open(struct input_dev *idev)
{
struct wm97xx *wm = input_get_drvdata(idev);
wm->ts_workq = create_singlethread_workqueue("kwm97xx");
if (wm->ts_workq == NULL) {
dev_err(wm->dev,
"Failed to create workqueue\n");
return -EINVAL;
}
/* start digitiser */
if (wm->mach_ops && wm->mach_ops->acc_enabled)
wm->codec->acc_enable(wm, 1);
wm->codec->dig_enable(wm, 1);
INIT_DELAYED_WORK(&wm->ts_reader, wm97xx_ts_reader);
INIT_WORK(&wm->pen_event_work, wm97xx_pen_irq_worker);
wm->ts_reader_min_interval = HZ >= 100 ? HZ / 100 : 1;
if (wm->ts_reader_min_interval < 1)
wm->ts_reader_min_interval = 1;
wm->ts_reader_interval = wm->ts_reader_min_interval;
wm->pen_is_down = 0;
if (wm->pen_irq)
wm97xx_init_pen_irq(wm);
else
dev_err(wm->dev, "No IRQ specified\n");
/* If we either don't have an interrupt for pen down events or
* failed to acquire it then we need to poll.
*/
if (wm->pen_irq == 0)
queue_delayed_work(wm->ts_workq, &wm->ts_reader,
wm->ts_reader_interval);
return 0;
}
/**
* wm97xx_ts_input_close - Close the touch screen input device.
* @idev: Input device to be closed.
*
* Called by the input sub system to close a wm97xx touchscreen
* device. Kills the touchscreen thread and stops the touch
* digitiser.
*/
static void wm97xx_ts_input_close(struct input_dev *idev)
{
struct wm97xx *wm = input_get_drvdata(idev);
u16 reg;
if (wm->pen_irq) {
/* Return the interrupt to GPIO usage (disabling it) */
if (wm->id != WM9705_ID2) {
BUG_ON(!wm->mach_ops->irq_gpio);
reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
wm97xx_reg_write(wm, AC97_MISC_AFE,
reg | wm->mach_ops->irq_gpio);
}
free_irq(wm->pen_irq, wm);
}
wm->pen_is_down = 0;
/* Balance out interrupt disables/enables */
if (cancel_work_sync(&wm->pen_event_work))
wm->mach_ops->irq_enable(wm, 1);
/* ts_reader rearms itself so we need to explicitly stop it
* before we destroy the workqueue.
*/
cancel_delayed_work_sync(&wm->ts_reader);
destroy_workqueue(wm->ts_workq);
/* stop digitiser */
wm->codec->dig_enable(wm, 0);
if (wm->mach_ops && wm->mach_ops->acc_enabled)
wm->codec->acc_enable(wm, 0);
}
static int wm97xx_probe(struct device *dev)
{
struct wm97xx *wm;
int ret = 0, id = 0;
wm = kzalloc(sizeof(struct wm97xx), GFP_KERNEL);
if (!wm)
return -ENOMEM;
mutex_init(&wm->codec_mutex);
wm->dev = dev;
dev->driver_data = wm;
wm->ac97 = to_ac97_t(dev);
/* check that we have a supported codec */
id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
if (id != WM97XX_ID1) {
dev_err(dev, "Device with vendor %04x is not a wm97xx\n", id);
ret = -ENODEV;
goto alloc_err;
}
wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
dev_info(wm->dev, "detected a wm97%02x codec\n", wm->id & 0xff);
switch (wm->id & 0xff) {
#ifdef CONFIG_TOUCHSCREEN_WM9705
case 0x05:
wm->codec = &wm9705_codec;
break;
#endif
#ifdef CONFIG_TOUCHSCREEN_WM9712
case 0x12:
wm->codec = &wm9712_codec;
break;
#endif
#ifdef CONFIG_TOUCHSCREEN_WM9713
case 0x13:
wm->codec = &wm9713_codec;
break;
#endif
default:
dev_err(wm->dev, "Support for wm97%02x not compiled in.\n",
wm->id & 0xff);
ret = -ENODEV;
goto alloc_err;
}
wm->input_dev = input_allocate_device();
if (wm->input_dev == NULL) {
ret = -ENOMEM;
goto alloc_err;
}
/* set up touch configuration */
wm->input_dev->name = "wm97xx touchscreen";
wm->input_dev->open = wm97xx_ts_input_open;
wm->input_dev->close = wm97xx_ts_input_close;
set_bit(EV_ABS, wm->input_dev->evbit);
set_bit(ABS_X, wm->input_dev->absbit);
set_bit(ABS_Y, wm->input_dev->absbit);
set_bit(ABS_PRESSURE, wm->input_dev->absbit);
input_set_abs_params(wm->input_dev, ABS_X, abs_x[0], abs_x[1],
abs_x[2], 0);
input_set_abs_params(wm->input_dev, ABS_Y, abs_y[0], abs_y[1],
abs_y[2], 0);
input_set_abs_params(wm->input_dev, ABS_PRESSURE, abs_p[0], abs_p[1],
abs_p[2], 0);
input_set_drvdata(wm->input_dev, wm);
wm->input_dev->dev.parent = dev;
ret = input_register_device(wm->input_dev);
if (ret < 0)
goto dev_alloc_err;
/* set up physical characteristics */
wm->codec->phy_init(wm);
/* load gpio cache */
wm->gpio[0] = wm97xx_reg_read(wm, AC97_GPIO_CFG);
wm->gpio[1] = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
wm->gpio[2] = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
wm->gpio[3] = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
wm->gpio[4] = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
wm->gpio[5] = wm97xx_reg_read(wm, AC97_MISC_AFE);
/* register our battery device */
wm->battery_dev = platform_device_alloc("wm97xx-battery", -1);
if (!wm->battery_dev) {
ret = -ENOMEM;
goto batt_err;
}
platform_set_drvdata(wm->battery_dev, wm);
wm->battery_dev->dev.parent = dev;
ret = platform_device_add(wm->battery_dev);
if (ret < 0)
goto batt_reg_err;
/* register our extended touch device (for machine specific
* extensions) */
wm->touch_dev = platform_device_alloc("wm97xx-touch", -1);
if (!wm->touch_dev) {
ret = -ENOMEM;
goto touch_err;
}
platform_set_drvdata(wm->touch_dev, wm);
wm->touch_dev->dev.parent = dev;
ret = platform_device_add(wm->touch_dev);
if (ret < 0)
goto touch_reg_err;
return ret;
touch_reg_err:
platform_device_put(wm->touch_dev);
touch_err:
platform_device_unregister(wm->battery_dev);
wm->battery_dev = NULL;
batt_reg_err:
platform_device_put(wm->battery_dev);
batt_err:
input_unregister_device(wm->input_dev);
wm->input_dev = NULL;
dev_alloc_err:
input_free_device(wm->input_dev);
alloc_err:
kfree(wm);
return ret;
}
static int wm97xx_remove(struct device *dev)
{
struct wm97xx *wm = dev_get_drvdata(dev);
platform_device_unregister(wm->battery_dev);
platform_device_unregister(wm->touch_dev);
input_unregister_device(wm->input_dev);
kfree(wm);
return 0;
}
#ifdef CONFIG_PM
static int wm97xx_suspend(struct device *dev, pm_message_t state)
{
struct wm97xx *wm = dev_get_drvdata(dev);
if (wm->input_dev->users)
cancel_delayed_work_sync(&wm->ts_reader);
return 0;
}
static int wm97xx_resume(struct device *dev)
{
struct wm97xx *wm = dev_get_drvdata(dev);
/* restore digitiser and gpios */
if (wm->id == WM9713_ID2) {
wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig[0]);
wm97xx_reg_write(wm, 0x5a, wm->misc);
if (wm->input_dev->users) {
u16 reg;
reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) & 0x7fff;
wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
}
}
wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig[1]);
wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2]);
wm97xx_reg_write(wm, AC97_GPIO_CFG, wm->gpio[0]);
wm97xx_reg_write(wm, AC97_GPIO_POLARITY, wm->gpio[1]);
wm97xx_reg_write(wm, AC97_GPIO_STICKY, wm->gpio[2]);
wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, wm->gpio[3]);
wm97xx_reg_write(wm, AC97_GPIO_STATUS, wm->gpio[4]);
wm97xx_reg_write(wm, AC97_MISC_AFE, wm->gpio[5]);
if (wm->input_dev->users && !wm->pen_irq) {
wm->ts_reader_interval = wm->ts_reader_min_interval;
queue_delayed_work(wm->ts_workq, &wm->ts_reader,
wm->ts_reader_interval);
}
return 0;
}
#else
#define wm97xx_suspend NULL
#define wm97xx_resume NULL
#endif
/*
* Machine specific operations
*/
int wm97xx_register_mach_ops(struct wm97xx *wm,
struct wm97xx_mach_ops *mach_ops)
{
mutex_lock(&wm->codec_mutex);
if (wm->mach_ops) {
mutex_unlock(&wm->codec_mutex);
return -EINVAL;
}
wm->mach_ops = mach_ops;
mutex_unlock(&wm->codec_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(wm97xx_register_mach_ops);
void wm97xx_unregister_mach_ops(struct wm97xx *wm)
{
mutex_lock(&wm->codec_mutex);
wm->mach_ops = NULL;
mutex_unlock(&wm->codec_mutex);
}
EXPORT_SYMBOL_GPL(wm97xx_unregister_mach_ops);
static struct device_driver wm97xx_driver = {
.name = "ac97",
.bus = &ac97_bus_type,
.owner = THIS_MODULE,
.probe = wm97xx_probe,
.remove = wm97xx_remove,
.suspend = wm97xx_suspend,
.resume = wm97xx_resume,
};
static int __init wm97xx_init(void)
{
return driver_register(&wm97xx_driver);
}
static void __exit wm97xx_exit(void)
{
driver_unregister(&wm97xx_driver);
}
module_init(wm97xx_init);
module_exit(wm97xx_exit);
/* Module information */
MODULE_AUTHOR("Liam Girdwood <liam.girdwood@wolfsonmicro.com>");
MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
MODULE_LICENSE("GPL");