* @reg: associated regulator (if specified).
* @nb: notifier block to handle notifications of voltage
* changes.
- * @supply_uV: local copy of supply voltage used to allow use of
+ * @supply_uv: local copy of supply voltage used to allow use of
* regulator consumer if available.
- * @supply_uV_valid: indicates that an updated value has not yet been
+ * @supply_uv_valid: indicates that an updated value has not yet been
* obtained from the regulator and so any calculations
* based upon it will be invalid.
- * @update_supply_work: work struct that is used to update the supply_uV.
+ * @update_supply_work: work struct that is used to update the supply_uv.
* @interrupt_handled: flag used to indicate a handler has been scheduled.
*/
struct sht15_data {
struct device *hwmon_dev;
struct regulator *reg;
struct notifier_block nb;
- int supply_uV;
- bool supply_uV_valid;
+ int supply_uv;
+ bool supply_uv_valid;
struct work_struct update_supply_work;
atomic_t interrupt_handled;
};
*
* This implements section 3.4 of the data sheet
*/
-static void sht15_connection_reset(struct sht15_data *data)
+static int sht15_connection_reset(struct sht15_data *data)
{
- int i;
+ int i, err;
- gpio_direction_output(data->pdata->gpio_data, 1);
+ err = gpio_direction_output(data->pdata->gpio_data, 1);
+ if (err)
+ return err;
ndelay(SHT15_TSCKL);
gpio_set_value(data->pdata->gpio_sck, 0);
ndelay(SHT15_TSCKL);
gpio_set_value(data->pdata->gpio_sck, 0);
ndelay(SHT15_TSCKL);
}
+ return 0;
}
/**
* conservative ones used in implementation. This implements
* figure 12 on the data sheet.
*/
-static void sht15_transmission_start(struct sht15_data *data)
+static int sht15_transmission_start(struct sht15_data *data)
{
+ int err;
+
/* ensure data is high and output */
- gpio_direction_output(data->pdata->gpio_data, 1);
+ err = gpio_direction_output(data->pdata->gpio_data, 1);
+ if (err)
+ return err;
ndelay(SHT15_TSU);
gpio_set_value(data->pdata->gpio_sck, 0);
ndelay(SHT15_TSCKL);
ndelay(SHT15_TSU);
gpio_set_value(data->pdata->gpio_sck, 0);
ndelay(SHT15_TSCKL);
+ return 0;
}
/**
*/
static int sht15_wait_for_response(struct sht15_data *data)
{
- gpio_direction_input(data->pdata->gpio_data);
+ int err;
+
+ err = gpio_direction_input(data->pdata->gpio_data);
+ if (err)
+ return err;
gpio_set_value(data->pdata->gpio_sck, 1);
ndelay(SHT15_TSCKH);
if (gpio_get_value(data->pdata->gpio_data)) {
gpio_set_value(data->pdata->gpio_sck, 0);
dev_err(data->dev, "Command not acknowledged\n");
- sht15_connection_reset(data);
+ err = sht15_connection_reset(data);
+ if (err)
+ return err;
return -EIO;
}
gpio_set_value(data->pdata->gpio_sck, 0);
*/
static int sht15_send_cmd(struct sht15_data *data, u8 cmd)
{
- int ret = 0;
+ int err;
- sht15_transmission_start(data);
+ err = sht15_transmission_start(data);
+ if (err)
+ return err;
sht15_send_byte(data, cmd);
- ret = sht15_wait_for_response(data);
- return ret;
+ return sht15_wait_for_response(data);
}
/**
* Each byte of data is acknowledged by pulling the data line
* low for one clock pulse.
*/
-static void sht15_ack(struct sht15_data *data)
+static int sht15_ack(struct sht15_data *data)
{
- gpio_direction_output(data->pdata->gpio_data, 0);
+ int err;
+
+ err = gpio_direction_output(data->pdata->gpio_data, 0);
+ if (err)
+ return err;
ndelay(SHT15_TSU);
gpio_set_value(data->pdata->gpio_sck, 1);
ndelay(SHT15_TSU);
ndelay(SHT15_TSU);
gpio_set_value(data->pdata->gpio_data, 1);
- gpio_direction_input(data->pdata->gpio_data);
+ return gpio_direction_input(data->pdata->gpio_data);
}
/**
*
* This is basically a NAK (single clock pulse, data high).
*/
-static void sht15_end_transmission(struct sht15_data *data)
+static int sht15_end_transmission(struct sht15_data *data)
{
- gpio_direction_output(data->pdata->gpio_data, 1);
+ int err;
+
+ err = gpio_direction_output(data->pdata->gpio_data, 1);
+ if (err)
+ return err;
ndelay(SHT15_TSU);
gpio_set_value(data->pdata->gpio_sck, 1);
ndelay(SHT15_TSCKH);
gpio_set_value(data->pdata->gpio_sck, 0);
ndelay(SHT15_TSCKL);
+ return 0;
}
/**
*/
static int sht15_send_status(struct sht15_data *data, u8 status)
{
- int ret;
-
- ret = sht15_send_cmd(data, SHT15_WRITE_STATUS);
- if (ret)
- return ret;
- gpio_direction_output(data->pdata->gpio_data, 1);
+ int err;
+
+ err = sht15_send_cmd(data, SHT15_WRITE_STATUS);
+ if (err)
+ return err;
+ err = gpio_direction_output(data->pdata->gpio_data, 1);
+ if (err)
+ return err;
ndelay(SHT15_TSU);
sht15_send_byte(data, status);
- ret = sht15_wait_for_response(data);
- if (ret)
- return ret;
+ err = sht15_wait_for_response(data);
+ if (err)
+ return err;
data->val_status = status;
return 0;
|| !data->status_valid) {
ret = sht15_send_cmd(data, SHT15_READ_STATUS);
if (ret)
- goto error_ret;
+ goto unlock;
status = sht15_read_byte(data);
if (data->checksumming) {
== dev_checksum);
}
- sht15_end_transmission(data);
+ ret = sht15_end_transmission(data);
+ if (ret)
+ goto unlock;
/*
* Perform checksum validation on the received data.
previous_config = data->val_status & 0x07;
ret = sht15_soft_reset(data);
if (ret)
- goto error_ret;
+ goto unlock;
if (previous_config) {
ret = sht15_send_status(data, previous_config);
if (ret) {
dev_err(data->dev,
"CRC validation failed, unable "
"to restore device settings\n");
- goto error_ret;
+ goto unlock;
}
}
ret = -EAGAIN;
- goto error_ret;
+ goto unlock;
}
data->val_status = status;
data->status_valid = true;
data->last_status = jiffies;
}
-error_ret:
- mutex_unlock(&data->read_lock);
+unlock:
+ mutex_unlock(&data->read_lock);
return ret;
}
if (ret)
return ret;
- gpio_direction_input(data->pdata->gpio_data);
+ ret = gpio_direction_input(data->pdata->gpio_data);
+ if (ret)
+ return ret;
atomic_set(&data->interrupt_handled, 0);
enable_irq(gpio_to_irq(data->pdata->gpio_data));
ret = wait_event_timeout(data->wait_queue,
(data->state == SHT15_READING_NOTHING),
msecs_to_jiffies(timeout_msecs));
- if (ret == 0) {/* timeout occurred */
+ if (data->state != SHT15_READING_NOTHING) { /* I/O error occurred */
+ data->state = SHT15_READING_NOTHING;
+ return -EIO;
+ } else if (ret == 0) { /* timeout occurred */
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
- sht15_connection_reset(data);
+ ret = sht15_connection_reset(data);
+ if (ret)
+ return ret;
return -ETIME;
}
data->state = SHT15_READING_HUMID;
ret = sht15_measurement(data, SHT15_MEASURE_RH, 160);
if (ret)
- goto error_ret;
+ goto unlock;
data->state = SHT15_READING_TEMP;
ret = sht15_measurement(data, SHT15_MEASURE_TEMP, 400);
if (ret)
- goto error_ret;
+ goto unlock;
data->measurements_valid = true;
data->last_measurement = jiffies;
}
-error_ret:
- mutex_unlock(&data->read_lock);
+unlock:
+ mutex_unlock(&data->read_lock);
return ret;
}
for (i = ARRAY_SIZE(temppoints) - 1; i > 0; i--)
/* Find pointer to interpolate */
- if (data->supply_uV > temppoints[i - 1].vdd) {
- d1 = (data->supply_uV - temppoints[i - 1].vdd)
+ if (data->supply_uv > temppoints[i - 1].vdd) {
+ d1 = (data->supply_uv - temppoints[i - 1].vdd)
* (temppoints[i].d1 - temppoints[i - 1].d1)
/ (temppoints[i].vdd - temppoints[i - 1].vdd)
+ temppoints[i - 1].d1;
/* Read the data back from the device */
val = sht15_read_byte(data);
val <<= 8;
- sht15_ack(data);
+ if (sht15_ack(data))
+ goto wakeup;
val |= sht15_read_byte(data);
if (data->checksumming) {
* Ask the device for a checksum and read it back.
* Note: the device sends the checksum byte reversed.
*/
- sht15_ack(data);
+ if (sht15_ack(data))
+ goto wakeup;
dev_checksum = sht15_reverse(sht15_read_byte(data));
checksum_vals[0] = (data->state == SHT15_READING_TEMP) ?
SHT15_MEASURE_TEMP : SHT15_MEASURE_RH;
}
/* Tell the device we are done */
- sht15_end_transmission(data);
+ if (sht15_end_transmission(data))
+ goto wakeup;
switch (data->state) {
case SHT15_READING_TEMP:
}
data->state = SHT15_READING_NOTHING;
+wakeup:
wake_up(&data->wait_queue);
}
struct sht15_data *data
= container_of(work_s, struct sht15_data,
update_supply_work);
- data->supply_uV = regulator_get_voltage(data->reg);
+ data->supply_uv = regulator_get_voltage(data->reg);
}
/**
struct sht15_data *data = container_of(nb, struct sht15_data, nb);
if (event == REGULATOR_EVENT_VOLTAGE_CHANGE)
- data->supply_uV_valid = false;
+ data->supply_uv_valid = false;
schedule_work(&data->update_supply_work);
return NOTIFY_OK;
return -EINVAL;
}
data->pdata = pdev->dev.platform_data;
- data->supply_uV = data->pdata->supply_mv * 1000;
+ data->supply_uv = data->pdata->supply_mv * 1000;
if (data->pdata->checksum)
data->checksumming = true;
if (data->pdata->no_otp_reload)
voltage = regulator_get_voltage(data->reg);
if (voltage)
- data->supply_uV = voltage;
+ data->supply_uv = voltage;
regulator_enable(data->reg);
/*
}
/* Try requesting the GPIOs */
- ret = devm_gpio_request(&pdev->dev, data->pdata->gpio_sck, "SHT15 sck");
+ ret = devm_gpio_request_one(&pdev->dev, data->pdata->gpio_sck,
+ GPIOF_OUT_INIT_LOW, "SHT15 sck");
if (ret) {
- dev_err(&pdev->dev, "gpio request failed\n");
+ dev_err(&pdev->dev, "clock line GPIO request failed\n");
goto err_release_reg;
}
- gpio_direction_output(data->pdata->gpio_sck, 0);
ret = devm_gpio_request(&pdev->dev, data->pdata->gpio_data,
"SHT15 data");
if (ret) {
- dev_err(&pdev->dev, "gpio request failed\n");
+ dev_err(&pdev->dev, "data line GPIO request failed\n");
goto err_release_reg;
}
goto err_release_reg;
}
disable_irq_nosync(gpio_to_irq(data->pdata->gpio_data));
- sht15_connection_reset(data);
+ ret = sht15_connection_reset(data);
+ if (ret)
+ goto err_release_reg;
ret = sht15_soft_reset(data);
if (ret)
goto err_release_reg;