/*
* 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/pm.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;
bool disabled; /* P: mutex */
bool gpio3; /* P: mutex */
bool gpio4; /* P: mutex */
spinlock_t lock;
struct timer_list timer; /* 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 bool gpio3;
module_param(gpio3, bool, 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[0].cs_change = 1;
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[0].cs_change = 1;
req->xfer[1].tx_buf = &req->ref_on;
req->xfer[1].len = 2;
req->xfer[1].delay_usecs = ts->vref_delay_usecs;
req->xfer[1].cs_change = 1;
req->xfer[2].tx_buf = &req->command;
req->xfer[2].len = 2;
req->xfer[2].delay_usecs = ts->vref_delay_usecs;
req->xfer[2].cs_change = 1;
req->xfer[3].rx_buf = &req->sample;
req->xfer[3].len = 2;
req->xfer[3].cs_change = 1;
req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/
req->xfer[4].len = 2;
req->xfer[4].cs_change = 1;
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 int ad7877_process_data(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;
/*
* Sample found inconsistent, pressure is beyond
* the maximum. Don't report it to user space.
*/
if (Rt > ts->pressure_max)
return -EINVAL;
if (!timer_pending(&ts->timer))
input_report_key(input_dev, BTN_TOUCH, 1);
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);
return 0;
}
return -EINVAL;
}
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_report_key(input_dev, BTN_TOUCH, 0);
input_sync(input_dev);
}
static void ad7877_timer(unsigned long handle)
{
struct ad7877 *ts = (void *)handle;
unsigned long flags;
spin_lock_irqsave(&ts->lock, flags);
ad7877_ts_event_release(ts);
spin_unlock_irqrestore(&ts->lock, flags);
}
static irqreturn_t ad7877_irq(int irq, void *handle)
{
struct ad7877 *ts = handle;
unsigned long flags;
int error;
error = spi_sync(ts->spi, &ts->msg);
if (error) {
dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
goto out;
}
spin_lock_irqsave(&ts->lock, flags);
error = ad7877_process_data(ts);
if (!error)
mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
spin_unlock_irqrestore(&ts->lock, flags);
out:
return IRQ_HANDLED;
}
static void ad7877_disable(struct ad7877 *ts)
{
mutex_lock(&ts->mutex);
if (!ts->disabled) {
ts->disabled = true;
disable_irq(ts->spi->irq);
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 = false;
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_aux3.attr,
&dev_attr_bat1.attr,
&dev_attr_bat2.attr,
&dev_attr_disable.attr,
&dev_attr_dac.attr,
&dev_attr_gpio3.attr,
&dev_attr_gpio4.attr,
NULL
};
static mode_t ad7877_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
mode_t mode = attr->mode;
if (attr == &dev_attr_aux3.attr) {
if (gpio3)
mode = 0;
} else if (attr == &dev_attr_gpio3.attr) {
if (!gpio3)
mode = 0;
}
return mode;
}
static const struct attribute_group ad7877_attr_group = {
.is_visible = ad7877_attr_is_visible,
.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->context = ts;
ts->xfer[0].tx_buf = &ts->cmd_crtl1;
ts->xfer[0].len = 2;
ts->xfer[0].cs_change = 1;
spi_message_add_tail(&ts->xfer[0], m);
ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */
ts->xfer[1].len = 2;
ts->xfer[1].cs_change = 1;
spi_message_add_tail(&ts->xfer[1], m);
for (i = 0; i < AD7877_NR_SENSE; i++) {
ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i];
ts->xfer[i + 2].len = 2;
if (i < (AD7877_NR_SENSE - 1))
ts->xfer[i + 2].cs_change = 1;
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_KEY, input_dev->evbit);
__set_bit(BTN_TOUCH, input_dev->keybit);
__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_threaded_irq(spi->irq, NULL, ad7877_irq,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
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 = input_register_device(input_dev);
if (err)
goto err_remove_attr_group;
return 0;
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);
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_SLEEP
static int ad7877_suspend(struct device *dev)
{
struct ad7877 *ts = dev_get_drvdata(dev);
ad7877_disable(ts);
return 0;
}
static int ad7877_resume(struct device *dev)
{
struct ad7877 *ts = dev_get_drvdata(dev);
ad7877_enable(ts);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume);
static struct spi_driver ad7877_driver = {
.driver = {
.name = "ad7877",
.bus = &spi_bus_type,
.owner = THIS_MODULE,
.pm = &ad7877_pm,
},
.probe = ad7877_probe,
.remove = __devexit_p(ad7877_remove),
};
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");