linux/drivers/input/touchscreen/ad7877.c
Oskar Schirmer cd9b6fdf79 Input: ad7877 - fix spi word size to 16 bit
With no word size given in the users platform data, a generic spi host
controller driver will assume a default word size of eight bit. This
causes transmission to be performed bytewise, which will fail on little
endian machines for sure. Failure on big endian depends on usage
of slave select to mark word boundaries.

Anyway, ad7877 is specified to work with 16 bit per word, so
unconditionally set the word size accordingly. Flag an error where 16
bit per word is not available.

Signed-off-by: Oskar Schirmer <os@emlix.com>
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Oliver Schneidewind <osw@emlix.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-06-08 01:13:05 -07:00

861 lines
21 KiB
C

/*
* Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc.
*
* Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver
* Based on: ads7846.c
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* History:
* Copyright (c) 2005 David Brownell
* Copyright (c) 2006 Nokia Corporation
* Various changes: Imre Deak <imre.deak@nokia.com>
*
* Using code from:
* - corgi_ts.c
* Copyright (C) 2004-2005 Richard Purdie
* - omap_ts.[hc], ads7846.h, ts_osk.c
* Copyright (C) 2002 MontaVista Software
* Copyright (C) 2004 Texas Instruments
* Copyright (C) 2005 Dirk Behme
*/
#include <linux/device.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/spi/ad7877.h>
#include <asm/irq.h>
#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100)
#define MAX_SPI_FREQ_HZ 20000000
#define MAX_12BIT ((1<<12)-1)
#define AD7877_REG_ZEROS 0
#define AD7877_REG_CTRL1 1
#define AD7877_REG_CTRL2 2
#define AD7877_REG_ALERT 3
#define AD7877_REG_AUX1HIGH 4
#define AD7877_REG_AUX1LOW 5
#define AD7877_REG_BAT1HIGH 6
#define AD7877_REG_BAT1LOW 7
#define AD7877_REG_BAT2HIGH 8
#define AD7877_REG_BAT2LOW 9
#define AD7877_REG_TEMP1HIGH 10
#define AD7877_REG_TEMP1LOW 11
#define AD7877_REG_SEQ0 12
#define AD7877_REG_SEQ1 13
#define AD7877_REG_DAC 14
#define AD7877_REG_NONE1 15
#define AD7877_REG_EXTWRITE 15
#define AD7877_REG_XPLUS 16
#define AD7877_REG_YPLUS 17
#define AD7877_REG_Z2 18
#define AD7877_REG_aux1 19
#define AD7877_REG_aux2 20
#define AD7877_REG_aux3 21
#define AD7877_REG_bat1 22
#define AD7877_REG_bat2 23
#define AD7877_REG_temp1 24
#define AD7877_REG_temp2 25
#define AD7877_REG_Z1 26
#define AD7877_REG_GPIOCTRL1 27
#define AD7877_REG_GPIOCTRL2 28
#define AD7877_REG_GPIODATA 29
#define AD7877_REG_NONE2 30
#define AD7877_REG_NONE3 31
#define AD7877_SEQ_YPLUS_BIT (1<<11)
#define AD7877_SEQ_XPLUS_BIT (1<<10)
#define AD7877_SEQ_Z2_BIT (1<<9)
#define AD7877_SEQ_AUX1_BIT (1<<8)
#define AD7877_SEQ_AUX2_BIT (1<<7)
#define AD7877_SEQ_AUX3_BIT (1<<6)
#define AD7877_SEQ_BAT1_BIT (1<<5)
#define AD7877_SEQ_BAT2_BIT (1<<4)
#define AD7877_SEQ_TEMP1_BIT (1<<3)
#define AD7877_SEQ_TEMP2_BIT (1<<2)
#define AD7877_SEQ_Z1_BIT (1<<1)
enum {
AD7877_SEQ_YPOS = 0,
AD7877_SEQ_XPOS = 1,
AD7877_SEQ_Z2 = 2,
AD7877_SEQ_AUX1 = 3,
AD7877_SEQ_AUX2 = 4,
AD7877_SEQ_AUX3 = 5,
AD7877_SEQ_BAT1 = 6,
AD7877_SEQ_BAT2 = 7,
AD7877_SEQ_TEMP1 = 8,
AD7877_SEQ_TEMP2 = 9,
AD7877_SEQ_Z1 = 10,
AD7877_NR_SENSE = 11,
};
/* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */
#define AD7877_DAC_CONF 0x1
/* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */
#define AD7877_EXTW_GPIO_3_CONF 0x1C4
#define AD7877_EXTW_GPIO_DATA 0x200
/* Control REG 2 */
#define AD7877_TMR(x) ((x & 0x3) << 0)
#define AD7877_REF(x) ((x & 0x1) << 2)
#define AD7877_POL(x) ((x & 0x1) << 3)
#define AD7877_FCD(x) ((x & 0x3) << 4)
#define AD7877_PM(x) ((x & 0x3) << 6)
#define AD7877_ACQ(x) ((x & 0x3) << 8)
#define AD7877_AVG(x) ((x & 0x3) << 10)
/* Control REG 1 */
#define AD7877_SER (1 << 11) /* non-differential */
#define AD7877_DFR (0 << 11) /* differential */
#define AD7877_MODE_NOC (0) /* Do not convert */
#define AD7877_MODE_SCC (1) /* Single channel conversion */
#define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */
#define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */
#define AD7877_CHANADD(x) ((x&0xF)<<7)
#define AD7877_READADD(x) ((x)<<2)
#define AD7877_WRITEADD(x) ((x)<<12)
#define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \
AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \
AD7877_READADD(AD7877_REG_ ## x))
#define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \
AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT)
/*
* Non-touchscreen sensors only use single-ended conversions.
*/
struct ser_req {
u16 reset;
u16 ref_on;
u16 command;
struct spi_message msg;
struct spi_transfer xfer[6];
/*
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
*/
u16 sample ____cacheline_aligned;
};
struct ad7877 {
struct input_dev *input;
char phys[32];
struct spi_device *spi;
u16 model;
u16 vref_delay_usecs;
u16 x_plate_ohms;
u16 pressure_max;
u16 cmd_crtl1;
u16 cmd_crtl2;
u16 cmd_dummy;
u16 dac;
u8 stopacq_polarity;
u8 first_conversion_delay;
u8 acquisition_time;
u8 averaging;
u8 pen_down_acc_interval;
struct spi_transfer xfer[AD7877_NR_SENSE + 2];
struct spi_message msg;
struct mutex mutex;
unsigned disabled:1; /* P: mutex */
unsigned gpio3:1; /* P: mutex */
unsigned gpio4:1; /* P: mutex */
spinlock_t lock;
struct timer_list timer; /* P: lock */
unsigned pending:1; /* P: lock */
/*
* DMA (thus cache coherency maintenance) requires the
* transfer buffers to live in their own cache lines.
*/
u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned;
};
static int gpio3;
module_param(gpio3, int, 0);
MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3");
/*
* ad7877_read/write are only used for initial setup and for sysfs controls.
* The main traffic is done using spi_async() in the interrupt handler.
*/
static int ad7877_read(struct spi_device *spi, u16 reg)
{
struct ser_req *req;
int status, ret;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
return -ENOMEM;
spi_message_init(&req->msg);
req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) |
AD7877_READADD(reg));
req->xfer[0].tx_buf = &req->command;
req->xfer[0].len = 2;
req->xfer[1].rx_buf = &req->sample;
req->xfer[1].len = 2;
spi_message_add_tail(&req->xfer[0], &req->msg);
spi_message_add_tail(&req->xfer[1], &req->msg);
status = spi_sync(spi, &req->msg);
ret = status ? : req->sample;
kfree(req);
return ret;
}
static int ad7877_write(struct spi_device *spi, u16 reg, u16 val)
{
struct ser_req *req;
int status;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
return -ENOMEM;
spi_message_init(&req->msg);
req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT));
req->xfer[0].tx_buf = &req->command;
req->xfer[0].len = 2;
spi_message_add_tail(&req->xfer[0], &req->msg);
status = spi_sync(spi, &req->msg);
kfree(req);
return status;
}
static int ad7877_read_adc(struct spi_device *spi, unsigned command)
{
struct ad7877 *ts = dev_get_drvdata(&spi->dev);
struct ser_req *req;
int status;
int sample;
int i;
req = kzalloc(sizeof *req, GFP_KERNEL);
if (!req)
return -ENOMEM;
spi_message_init(&req->msg);
/* activate reference, so it has time to settle; */
req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) |
AD7877_POL(ts->stopacq_polarity) |
AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) |
AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0);
req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC;
req->command = (u16) command;
req->xfer[0].tx_buf = &req->reset;
req->xfer[0].len = 2;
req->xfer[1].tx_buf = &req->ref_on;
req->xfer[1].len = 2;
req->xfer[1].delay_usecs = ts->vref_delay_usecs;
req->xfer[2].tx_buf = &req->command;
req->xfer[2].len = 2;
req->xfer[2].delay_usecs = ts->vref_delay_usecs;
req->xfer[3].rx_buf = &req->sample;
req->xfer[3].len = 2;
req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/
req->xfer[4].len = 2;
req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/
req->xfer[5].len = 2;
/* group all the transfers together, so we can't interfere with
* reading touchscreen state; disable penirq while sampling
*/
for (i = 0; i < 6; i++)
spi_message_add_tail(&req->xfer[i], &req->msg);
status = spi_sync(spi, &req->msg);
sample = req->sample;
kfree(req);
return status ? : sample;
}
static void ad7877_rx(struct ad7877 *ts)
{
struct input_dev *input_dev = ts->input;
unsigned Rt;
u16 x, y, z1, z2;
x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT;
y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT;
z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT;
z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT;
/*
* The samples processed here are already preprocessed by the AD7877.
* The preprocessing function consists of an averaging filter.
* The combination of 'first conversion delay' and averaging provides a robust solution,
* discarding the spurious noise in the signal and keeping only the data of interest.
* The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h)
* Other user-programmable conversion controls include variable acquisition time,
* and first conversion delay. Up to 16 averages can be taken per conversion.
*/
if (likely(x && z1)) {
/* compute touch pressure resistance using equation #1 */
Rt = (z2 - z1) * x * ts->x_plate_ohms;
Rt /= z1;
Rt = (Rt + 2047) >> 12;
input_report_abs(input_dev, ABS_X, x);
input_report_abs(input_dev, ABS_Y, y);
input_report_abs(input_dev, ABS_PRESSURE, Rt);
input_sync(input_dev);
}
}
static inline void ad7877_ts_event_release(struct ad7877 *ts)
{
struct input_dev *input_dev = ts->input;
input_report_abs(input_dev, ABS_PRESSURE, 0);
input_sync(input_dev);
}
static void ad7877_timer(unsigned long handle)
{
struct ad7877 *ts = (void *)handle;
ad7877_ts_event_release(ts);
}
static irqreturn_t ad7877_irq(int irq, void *handle)
{
struct ad7877 *ts = handle;
unsigned long flags;
int status;
/*
* The repeated conversion sequencer controlled by TMR kicked off
* too fast. We ignore the last and process the sample sequence
* currently in the queue. It can't be older than 9.4ms, and we
* need to avoid that ts->msg doesn't get issued twice while in work.
*/
spin_lock_irqsave(&ts->lock, flags);
if (!ts->pending) {
ts->pending = 1;
status = spi_async(ts->spi, &ts->msg);
if (status)
dev_err(&ts->spi->dev, "spi_sync --> %d\n", status);
}
spin_unlock_irqrestore(&ts->lock, flags);
return IRQ_HANDLED;
}
static void ad7877_callback(void *_ts)
{
struct ad7877 *ts = _ts;
spin_lock_irq(&ts->lock);
ad7877_rx(ts);
ts->pending = 0;
mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
spin_unlock_irq(&ts->lock);
}
static void ad7877_disable(struct ad7877 *ts)
{
mutex_lock(&ts->mutex);
if (!ts->disabled) {
ts->disabled = 1;
disable_irq(ts->spi->irq);
/* Wait for spi_async callback */
while (ts->pending)
msleep(1);
if (del_timer_sync(&ts->timer))
ad7877_ts_event_release(ts);
}
/* we know the chip's in lowpower mode since we always
* leave it that way after every request
*/
mutex_unlock(&ts->mutex);
}
static void ad7877_enable(struct ad7877 *ts)
{
mutex_lock(&ts->mutex);
if (ts->disabled) {
ts->disabled = 0;
enable_irq(ts->spi->irq);
}
mutex_unlock(&ts->mutex);
}
#define SHOW(name) static ssize_t \
name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
{ \
struct ad7877 *ts = dev_get_drvdata(dev); \
ssize_t v = ad7877_read_adc(ts->spi, \
AD7877_READ_CHAN(name)); \
if (v < 0) \
return v; \
return sprintf(buf, "%u\n", (unsigned) v); \
} \
static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
SHOW(aux1)
SHOW(aux2)
SHOW(aux3)
SHOW(bat1)
SHOW(bat2)
SHOW(temp1)
SHOW(temp2)
static ssize_t ad7877_disable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ad7877 *ts = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", ts->disabled);
}
static ssize_t ad7877_disable_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ad7877 *ts = dev_get_drvdata(dev);
unsigned long val;
int error;
error = strict_strtoul(buf, 10, &val);
if (error)
return error;
if (val)
ad7877_disable(ts);
else
ad7877_enable(ts);
return count;
}
static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store);
static ssize_t ad7877_dac_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ad7877 *ts = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", ts->dac);
}
static ssize_t ad7877_dac_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ad7877 *ts = dev_get_drvdata(dev);
unsigned long val;
int error;
error = strict_strtoul(buf, 10, &val);
if (error)
return error;
mutex_lock(&ts->mutex);
ts->dac = val & 0xFF;
ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF);
mutex_unlock(&ts->mutex);
return count;
}
static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store);
static ssize_t ad7877_gpio3_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ad7877 *ts = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", ts->gpio3);
}
static ssize_t ad7877_gpio3_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ad7877 *ts = dev_get_drvdata(dev);
unsigned long val;
int error;
error = strict_strtoul(buf, 10, &val);
if (error)
return error;
mutex_lock(&ts->mutex);
ts->gpio3 = !!val;
ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
(ts->gpio4 << 4) | (ts->gpio3 << 5));
mutex_unlock(&ts->mutex);
return count;
}
static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store);
static ssize_t ad7877_gpio4_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ad7877 *ts = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", ts->gpio4);
}
static ssize_t ad7877_gpio4_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct ad7877 *ts = dev_get_drvdata(dev);
unsigned long val;
int error;
error = strict_strtoul(buf, 10, &val);
if (error)
return error;
mutex_lock(&ts->mutex);
ts->gpio4 = !!val;
ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
(ts->gpio4 << 4) | (ts->gpio3 << 5));
mutex_unlock(&ts->mutex);
return count;
}
static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store);
static struct attribute *ad7877_attributes[] = {
&dev_attr_temp1.attr,
&dev_attr_temp2.attr,
&dev_attr_aux1.attr,
&dev_attr_aux2.attr,
&dev_attr_bat1.attr,
&dev_attr_bat2.attr,
&dev_attr_disable.attr,
&dev_attr_dac.attr,
&dev_attr_gpio4.attr,
NULL
};
static const struct attribute_group ad7877_attr_group = {
.attrs = ad7877_attributes,
};
static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts)
{
struct spi_message *m;
int i;
ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) |
AD7877_POL(ts->stopacq_polarity) |
AD7877_AVG(ts->averaging) | AD7877_PM(1) |
AD7877_TMR(ts->pen_down_acc_interval) |
AD7877_ACQ(ts->acquisition_time) |
AD7877_FCD(ts->first_conversion_delay);
ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2);
ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) |
AD7877_READADD(AD7877_REG_XPLUS-1) |
AD7877_MODE_SEQ1 | AD7877_DFR;
ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1);
ts->cmd_dummy = 0;
m = &ts->msg;
spi_message_init(m);
m->complete = ad7877_callback;
m->context = ts;
ts->xfer[0].tx_buf = &ts->cmd_crtl1;
ts->xfer[0].len = 2;
spi_message_add_tail(&ts->xfer[0], m);
ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */
ts->xfer[1].len = 2;
spi_message_add_tail(&ts->xfer[1], m);
for (i = 0; i < 11; i++) {
ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i];
ts->xfer[i + 2].len = 2;
spi_message_add_tail(&ts->xfer[i + 2], m);
}
}
static int __devinit ad7877_probe(struct spi_device *spi)
{
struct ad7877 *ts;
struct input_dev *input_dev;
struct ad7877_platform_data *pdata = spi->dev.platform_data;
int err;
u16 verify;
if (!spi->irq) {
dev_dbg(&spi->dev, "no IRQ?\n");
return -ENODEV;
}
if (!pdata) {
dev_dbg(&spi->dev, "no platform data?\n");
return -ENODEV;
}
/* don't exceed max specified SPI CLK frequency */
if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz);
return -EINVAL;
}
spi->bits_per_word = 16;
err = spi_setup(spi);
if (err) {
dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n");
return err;
}
ts = kzalloc(sizeof(struct ad7877), GFP_KERNEL);
input_dev = input_allocate_device();
if (!ts || !input_dev) {
err = -ENOMEM;
goto err_free_mem;
}
dev_set_drvdata(&spi->dev, ts);
ts->spi = spi;
ts->input = input_dev;
setup_timer(&ts->timer, ad7877_timer, (unsigned long) ts);
mutex_init(&ts->mutex);
spin_lock_init(&ts->lock);
ts->model = pdata->model ? : 7877;
ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
ts->pressure_max = pdata->pressure_max ? : ~0;
ts->stopacq_polarity = pdata->stopacq_polarity;
ts->first_conversion_delay = pdata->first_conversion_delay;
ts->acquisition_time = pdata->acquisition_time;
ts->averaging = pdata->averaging;
ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
input_dev->name = "AD7877 Touchscreen";
input_dev->phys = ts->phys;
input_dev->dev.parent = &spi->dev;
__set_bit(EV_ABS, input_dev->evbit);
__set_bit(ABS_X, input_dev->absbit);
__set_bit(ABS_Y, input_dev->absbit);
__set_bit(ABS_PRESSURE, input_dev->absbit);
input_set_abs_params(input_dev, ABS_X,
pdata->x_min ? : 0,
pdata->x_max ? : MAX_12BIT,
0, 0);
input_set_abs_params(input_dev, ABS_Y,
pdata->y_min ? : 0,
pdata->y_max ? : MAX_12BIT,
0, 0);
input_set_abs_params(input_dev, ABS_PRESSURE,
pdata->pressure_min, pdata->pressure_max, 0, 0);
ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE);
verify = ad7877_read(spi, AD7877_REG_SEQ1);
if (verify != AD7877_MM_SEQUENCE){
dev_err(&spi->dev, "%s: Failed to probe %s\n",
dev_name(&spi->dev), input_dev->name);
err = -ENODEV;
goto err_free_mem;
}
if (gpio3)
ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF);
ad7877_setup_ts_def_msg(spi, ts);
/* Request AD7877 /DAV GPIO interrupt */
err = request_irq(spi->irq, ad7877_irq, IRQF_TRIGGER_FALLING,
spi->dev.driver->name, ts);
if (err) {
dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
goto err_free_mem;
}
err = sysfs_create_group(&spi->dev.kobj, &ad7877_attr_group);
if (err)
goto err_free_irq;
err = device_create_file(&spi->dev,
gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3);
if (err)
goto err_remove_attr_group;
err = input_register_device(input_dev);
if (err)
goto err_remove_attr;
return 0;
err_remove_attr:
device_remove_file(&spi->dev,
gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3);
err_remove_attr_group:
sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
err_free_irq:
free_irq(spi->irq, ts);
err_free_mem:
input_free_device(input_dev);
kfree(ts);
dev_set_drvdata(&spi->dev, NULL);
return err;
}
static int __devexit ad7877_remove(struct spi_device *spi)
{
struct ad7877 *ts = dev_get_drvdata(&spi->dev);
sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
device_remove_file(&spi->dev,
gpio3 ? &dev_attr_gpio3 : &dev_attr_aux3);
ad7877_disable(ts);
free_irq(ts->spi->irq, ts);
input_unregister_device(ts->input);
kfree(ts);
dev_dbg(&spi->dev, "unregistered touchscreen\n");
dev_set_drvdata(&spi->dev, NULL);
return 0;
}
#ifdef CONFIG_PM
static int ad7877_suspend(struct spi_device *spi, pm_message_t message)
{
struct ad7877 *ts = dev_get_drvdata(&spi->dev);
ad7877_disable(ts);
return 0;
}
static int ad7877_resume(struct spi_device *spi)
{
struct ad7877 *ts = dev_get_drvdata(&spi->dev);
ad7877_enable(ts);
return 0;
}
#else
#define ad7877_suspend NULL
#define ad7877_resume NULL
#endif
static struct spi_driver ad7877_driver = {
.driver = {
.name = "ad7877",
.bus = &spi_bus_type,
.owner = THIS_MODULE,
},
.probe = ad7877_probe,
.remove = __devexit_p(ad7877_remove),
.suspend = ad7877_suspend,
.resume = ad7877_resume,
};
static int __init ad7877_init(void)
{
return spi_register_driver(&ad7877_driver);
}
module_init(ad7877_init);
static void __exit ad7877_exit(void)
{
spi_unregister_driver(&ad7877_driver);
}
module_exit(ad7877_exit);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("AD7877 touchscreen Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:ad7877");