From: Michael Hennerich

[try #4] Changelog (based on LKML feedback by Dmitry Torokhov)
- Fix req use after free.
- Fix sysfs interaction (we migh re-eanble irgs upon a sysfs read).
- Fix DAC bogus data read case

[try #3] Changlog (Add feedback from Dmitry Torokhov):
- Change handling of spi_sync / spi_async return value handling
- Remove depreciated dev->power.power_state
- Fix error return path in ad7877_probe
- delete pending kernel timer
- Some minor cleanup (indention, use dev_err etc.)

[try #2] Changelog:
- move locking inside ad7877_enable and ad7877_disable
- use setup_timer
- use input_dev->dev.parent
- fix unregister device
- kill EV_KEY since it's not used
- fix indention style

Apply patch from Philip Douglass:
Make ad7877 ts driver not dependent on Blackfin specific cs_change_per_word_option

Cc: Dmitry Torokhov
Signed-off-by: Michael Hennerich
Signed-off-by: Bryan Wu
Signed-off-by: Bryan Wu
---
drivers/input/touchscreen/Kconfig | 13 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/ad7877.c | 902 ++++++++++++++++++++++++++++++++++++
3 files changed, 916 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/ad7877.c

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 565ec71..4fdde92 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -29,6 +29,19 @@ config TOUCHSCREEN_ADS7846
To compile this driver as a module, choose M here: the
module will be called ads7846.

+config TOUCHSCREEN_AD7877
+ tristate "AD7877 based touchscreens"
+ depends on SPI_MASTER
+ help
+ Say Y here if you have a touchscreen interface using the
+ AD7877 controller, and your board-specific initialization
+ code includes that in its table of SPI devices.
+
+ If unsure, say N (but it's safe to say "Y").
+
+ To compile this driver as a module, choose M here: the
+ module will be called ad7877.
+
config TOUCHSCREEN_BITSY
tristate "Compaq iPAQ H3600 (Bitsy) touchscreen"
depends on SA1100_BITSY
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 3c096d7..18b89c5 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -6,6 +6,7 @@

wm97xx-ts-y := wm97xx-core.o

+obj-$(CONFIG_TOUCHSCREEN_AD7877) += ad7877.o
obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
obj-$(CONFIG_TOUCHSCREEN_BITSY) += h3600_ts_input.o
obj-$(CONFIG_TOUCHSCREEN_CORGI) += corgi_ts.o
diff --git a/drivers/input/touchscreen/ad7877.c b/drivers/input/touchscreen/ad7877.c
new file mode 100644
index 0000000..cc7d0cb
--- /dev/null
+++ b/drivers/input/touchscreen/ad7877.c
@@ -0,0 +1,902 @@
+/*
+ * File: drivers/input/touchscreen/ad7877.c
+ *
+ * Based on: ads7846.c
+ *
+ * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc.
+ *
+ * Author: Michael Hennerich, Analog Devices Inc.
+ *
+ * Created: Nov, 10th 2006
+ * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver
+ *
+ *
+ * Modified:
+ *
+ * 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
+ *
+ * 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
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50)
+
+/*--------------------------------------------------------------------------*/
+
+#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;
+ u16 sample;
+ struct spi_message msg;
+ struct spi_transfer xfer[6];
+};
+
+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;
+
+ u16 conversion_data[AD7877_NR_SENSE];
+
+ struct spi_transfer xfer[13];
+ struct spi_message msg;
+
+ spinlock_t lock;
+ struct timer_list timer; /* P: lock */
+ unsigned pendown:1; /* P: lock */
+ unsigned pending:1; /* P: lock */
+
+ unsigned irq_disabled:1; /* P: lock */
+ unsigned disabled:1;
+ unsigned intr_flag:1;
+ unsigned gpio3:1;
+ unsigned gpio4:1;
+};
+
+static int gpio3;
+
+static void ad7877_enable(struct ad7877 *ts);
+static void ad7877_disable(struct ad7877 *ts);
+
+static int ad7877_read(struct device *dev, u16 reg)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL);
+ int status, ret;
+
+ 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);
+
+ if (status == 0)
+ status = req->msg.status;
+
+ ret = status ? status : req->sample;
+ kfree(req);
+
+ return ret;
+}
+
+static int ad7877_write(struct device *dev, u16 reg, u16 val)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL);
+ int status;
+
+ 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);
+
+ if (status == 0)
+ status = req->msg.status;
+
+ kfree(req);
+
+ return status;
+}
+
+static int ad7877_read_adc(struct device *dev, unsigned command)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct ad7877 *ts = dev_get_drvdata(dev);
+ struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL);
+ int status;
+ int sample;
+ int i;
+
+ 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);
+
+ if (status == 0)
+ status = req->msg.status;
+
+ sample = req->sample;
+
+ kfree(req);
+ return status ? status : sample;
+}
+
+#define SHOW(name) static ssize_t \
+name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
+{ \
+ ssize_t v = ad7877_read_adc(dev, \
+ 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);
+ char *endp;
+ int i;
+
+ i = simple_strtoul(buf, &endp, 10);
+
+ if (i)
+ 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);
+ char *endp;
+ int i;
+
+ i = simple_strtoul(buf, &endp, 10);
+
+ ts->dac = i & 0xFF;
+
+ ad7877_write(dev, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF);
+
+ 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);
+ char *endp;
+ int i;
+
+ i = simple_strtoul(buf, &endp, 10);
+
+ ts->gpio3 = !!i;
+
+ ad7877_write(dev, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
+ (ts->gpio4 << 4) | (ts->gpio3 << 5));
+
+ 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);
+ char *endp;
+ int i;
+
+ i = simple_strtoul(buf, &endp, 10);
+
+ ts->gpio4 = !!i;
+
+ ad7877_write(dev, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
+ (ts->gpio4 << 4) | (ts->gpio3 << 5));
+
+ 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,
+};
+
+/*--------------------------------------------------------------------------*/
+
+/*
+ * /DAV Data available Interrupt only kicks the kthread.
+ * The kthread kicks the timer only to issue the Pen Up Event if
+ * no new data is available
+ *
+ */
+
+static void ad7877_rx(void *ads)
+{
+ struct ad7877 *ts = ads;
+ 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;
+
+ /* range filtering */
+ if (x == MAX_12BIT)
+ x = 0;
+
+ if (likely(x && z1)) {
+ /* compute touch pressure resistance using equation #2 */
+ Rt = z2;
+ Rt -= z1;
+ Rt *= x;
+ Rt *= ts->x_plate_ohms;
+ Rt /= z1;
+ Rt = (Rt + 2047) >> 12;
+ } else
+ Rt = 0;
+
+ if (Rt) {
+ 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);
+#ifdef VERBOSE
+ pr_debug("%s: %d/%d/%d%s\n", ts->spi->dev.bus_id,
+ x, y, Rt, Rt ? "" : " UP");
+#endif
+ }
+}
+
+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;
+
+ spin_lock_irqsave(&ts->lock, flags);
+
+ if (!ts->irq_disabled) {
+ ts->irq_disabled = 1;
+ disable_irq(ts->spi->irq);
+ ts->pending = 1;
+ }
+
+ ts->intr_flag = 1;
+
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ status = spi_async(ts->spi, &ts->msg);
+
+ if (status)
+ dev_err(&ts->spi->dev, "spi_sync --> %d\n", status);
+
+ return IRQ_HANDLED;
+}
+
+
+static void ad7877_callback(void *_ts)
+{
+ struct ad7877 *ts = _ts;
+ unsigned long flags;
+
+ if (ts->intr_flag) {
+
+ ad7877_rx(ts);
+
+ spin_lock_irqsave(&ts->lock, flags);
+
+ ts->intr_flag = 0;
+ ts->pending = 0;
+ ts->irq_disabled = 0;
+ enable_irq(ts->spi->irq);
+ mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
+
+ spin_unlock_irqrestore(&ts->lock, flags);
+ }
+}
+
+
+/*--------------------------------------------------------------------------*/
+
+static void ad7877_disable(struct ad7877 *ts)
+{
+ unsigned long flags;
+
+ if (ts->disabled)
+ return;
+
+ ts->disabled = 1;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ ts->irq_disabled = 1;
+ disable_irq(ts->spi->irq);
+ spin_unlock_irqrestore(&ts->lock, flags);
+
+ while (ts->pending) /* Wait for spi_async callback */
+ 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
+ */
+}
+
+/* Must be called with ts->lock held */
+static void ad7877_enable(struct ad7877 *ts)
+{
+ unsigned long flags;
+
+ if (!ts->disabled)
+ return;
+
+ spin_lock_irqsave(&ts->lock, flags);
+ ts->disabled = 0;
+ ts->irq_disabled = 0;
+ enable_irq(ts->spi->irq);
+ spin_unlock_irqrestore(&ts->lock, flags);
+}
+
+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;
+}
+
+static inline 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((struct device *) 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((struct device *) 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;
+ }
+
+ 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;
+ ts->intr_flag = 0;
+
+ setup_timer(&ts->timer, ad7877_timer, (unsigned long) ts);
+
+ 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", spi->dev.bus_id);
+
+ 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((struct device *) spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE);
+
+ verify = ad7877_read((struct device *) spi, AD7877_REG_SEQ1);
+
+ if (verify != AD7877_MM_SEQUENCE){
+ dev_err(&spi->dev, "%s: Failed to probe %s\n", spi->dev.bus_id,
+ input_dev->name);
+ err = -ENODEV;
+ goto err_free_mem;
+ }
+
+ if (gpio3)
+ ad7877_write((struct device *) spi, AD7877_REG_EXTWRITE,
+ AD7877_EXTW_GPIO_3_CONF);
+
+ ad7877_setup_ts_def_msg(spi, ts);
+
+ /* Request AD7877 /DAV GPIO interrupt */
+
+ if (request_irq(spi->irq, ad7877_irq, IRQF_TRIGGER_LOW | IRQF_SAMPLE_RANDOM,
+ spi->dev.driver->name, ts)) {
+ dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
+ err = -EBUSY;
+ goto err_free_mem;
+ }
+
+ dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);
+
+ err = sysfs_create_group(&spi->dev.kobj, &ad7877_attr_group);
+ if (err)
+ goto err_remove_attr;
+
+ if (gpio3)
+ err = device_create_file(&spi->dev, &dev_attr_gpio3);
+ else
+ err = device_create_file(&spi->dev, &dev_attr_aux3);
+
+ if (err)
+ goto err_remove_attr;
+
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_remove_attr;
+
+ ts->intr_flag = 0;
+
+ return 0;
+
+err_remove_attr:
+
+ sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
+
+ if (gpio3)
+ device_remove_file(&spi->dev, &dev_attr_gpio3);
+ else
+ device_remove_file(&spi->dev, &dev_attr_aux3);
+
+ 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);
+
+ ad7877_suspend(spi, PMSG_SUSPEND);
+
+ sysfs_remove_group(&spi->dev.kobj, &ad7877_attr_group);
+
+ if (gpio3)
+ device_remove_file(&spi->dev, &dev_attr_gpio3);
+ else
+ device_remove_file(&spi->dev, &dev_attr_aux3);
+
+ 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;
+}
+
+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_param(gpio3, int, 0);
+MODULE_PARM_DESC(gpio3,
+ "If gpio3 is set to 1 AUX3 acts as GPIO3");
+
+MODULE_DESCRIPTION("ad7877 TouchScreen Driver");
+MODULE_LICENSE("GPL");
--
1.5.5
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