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Input: tsc2005 - handle read errors from SPI layer
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Tested-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
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Dmitry Torokhov committed Mar 17, 2011
1 parent dacb650 commit 71f8004
Showing 1 changed file with 81 additions and 19 deletions.
100 changes: 81 additions & 19 deletions drivers/input/touchscreen/tsc2005.c
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Original file line number Diff line number Diff line change
Expand Up @@ -146,7 +146,7 @@ struct tsc2005 {
void (*set_reset)(bool enable);
};

static void tsc2005_cmd(struct tsc2005 *ts, u8 cmd)
static int tsc2005_cmd(struct tsc2005 *ts, u8 cmd)
{
u8 tx = TSC2005_CMD | TSC2005_CMD_12BIT | cmd;
struct spi_transfer xfer = {
Expand All @@ -155,13 +155,22 @@ static void tsc2005_cmd(struct tsc2005 *ts, u8 cmd)
.bits_per_word = 8,
};
struct spi_message msg;
int error;

spi_message_init(&msg);
spi_message_add_tail(&xfer, &msg);
spi_sync(ts->spi, &msg);

error = spi_sync(ts->spi, &msg);
if (error) {
dev_err(&ts->spi->dev, "%s: failed, command: %x, error: %d\n",
__func__, cmd, error);
return error;
}

return 0;
}

static void tsc2005_write(struct tsc2005 *ts, u8 reg, u16 value)
static int tsc2005_write(struct tsc2005 *ts, u8 reg, u16 value)
{
u32 tx = ((reg | TSC2005_REG_PND0) << 16) | value;
struct spi_transfer xfer = {
Expand All @@ -170,10 +179,20 @@ static void tsc2005_write(struct tsc2005 *ts, u8 reg, u16 value)
.bits_per_word = 24,
};
struct spi_message msg;
int error;

spi_message_init(&msg);
spi_message_add_tail(&xfer, &msg);
spi_sync(ts->spi, &msg);

error = spi_sync(ts->spi, &msg);
if (error) {
dev_err(&ts->spi->dev,
"%s: failed, register: %x, value: %x, error: %d\n",
__func__, reg, value, error);
return error;
}

return 0;
}

static void tsc2005_setup_read(struct tsc2005_spi_rd *rd, u8 reg, bool last)
Expand All @@ -188,18 +207,23 @@ static void tsc2005_setup_read(struct tsc2005_spi_rd *rd, u8 reg, bool last)
rd->spi_xfer.cs_change = !last;
}

static void tsc2005_read(struct tsc2005 *ts, u8 reg, u16 *value)
static int tsc2005_read(struct tsc2005 *ts, u8 reg, u16 *value)
{
struct tsc2005_spi_rd spi_rd;
struct spi_message msg;
int error;

tsc2005_setup_read(&spi_rd, reg, true);

spi_message_init(&msg);
spi_message_add_tail(&spi_rd.spi_xfer, &msg);
spi_sync(ts->spi, &msg);

error = spi_sync(ts->spi, &msg);
if (error)
return error;

*value = spi_rd.spi_rx;
return 0;
}

static void tsc2005_update_pen_state(struct tsc2005 *ts,
Expand Down Expand Up @@ -232,14 +256,18 @@ static irqreturn_t tsc2005_irq_thread(int irq, void *_ts)
unsigned int pressure;
u32 x, y;
u32 z1, z2;
int error;

mutex_lock(&ts->mutex);

if (unlikely(ts->disable_depth))
goto out;

/* read the coordinates */
spi_sync(ts->spi, &ts->spi_read_msg);
error = spi_sync(ts->spi, &ts->spi_read_msg);
if (unlikely(error))
goto out;

x = ts->spi_x.spi_rx;
y = ts->spi_y.spi_rx;
z1 = ts->spi_z1.spi_rx;
Expand Down Expand Up @@ -392,42 +420,74 @@ static ssize_t tsc2005_selftest_show(struct device *dev,
u16 temp_high;
u16 temp_high_orig;
u16 temp_high_test;
unsigned int result;
bool success = true;
int error;

mutex_lock(&ts->mutex);

/*
* Test TSC2005 communications via temp high register.
*/
tsc2005_disable(ts);
result = 1;
tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high_orig);

error = tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high_orig);
if (error) {
dev_warn(dev, "selftest failed: read error %d\n", error);
success = false;
goto out;
}

temp_high_test = (temp_high_orig - 1) & MAX_12BIT;
tsc2005_write(ts, TSC2005_REG_TEMP_HIGH, temp_high_test);
tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);

error = tsc2005_write(ts, TSC2005_REG_TEMP_HIGH, temp_high_test);
if (error) {
dev_warn(dev, "selftest failed: write error %d\n", error);
success = false;
goto out;
}

error = tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);
if (error) {
dev_warn(dev, "selftest failed: read error %d after write\n",
error);
success = false;
goto out;
}

if (temp_high != temp_high_test) {
dev_warn(dev, "selftest failed: %d != %d\n",
temp_high, temp_high_test);
result = 0;
success = false;
}

/* hardware reset */
ts->set_reset(false);
usleep_range(100, 500); /* only 10us required */
ts->set_reset(true);
tsc2005_enable(ts);

if (!success)
goto out;

/* test that the reset really happened */
tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);
error = tsc2005_read(ts, TSC2005_REG_TEMP_HIGH, &temp_high);
if (error) {
dev_warn(dev, "selftest failed: read error %d after reset\n",
error);
success = false;
goto out;
}

if (temp_high != temp_high_orig) {
dev_warn(dev, "selftest failed after reset: %d != %d\n",
temp_high, temp_high_orig);
result = 0;
success = false;
}

out:
tsc2005_enable(ts);
mutex_unlock(&ts->mutex);

return sprintf(buf, "%u\n", result);
return sprintf(buf, "%d\n", success);
}

static DEVICE_ATTR(selftest, S_IRUGO, tsc2005_selftest_show, NULL);
Expand Down Expand Up @@ -469,6 +529,7 @@ static void tsc2005_esd_timer(unsigned long data)
static void tsc2005_esd_work(struct work_struct *work)
{
struct tsc2005 *ts = container_of(work, struct tsc2005, esd_work);
int error;
u16 r;

mutex_lock(&ts->mutex);
Expand All @@ -480,8 +541,9 @@ static void tsc2005_esd_work(struct work_struct *work)
* If we cannot read our known value from configuration register 0 then
* reset the controller as if from power-up and start scanning again.
*/
tsc2005_read(ts, TSC2005_REG_CFR0, &r);
if ((r ^ TSC2005_CFR0_INITVALUE) & TSC2005_CFR0_RW_MASK) {
error = tsc2005_read(ts, TSC2005_REG_CFR0, &r);
if (error ||
((r ^ TSC2005_CFR0_INITVALUE) & TSC2005_CFR0_RW_MASK)) {
dev_info(&ts->spi->dev, "TSC2005 not responding - resetting\n");
ts->set_reset(false);
tsc2005_update_pen_state(ts, 0, 0, 0);
Expand Down

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