In an effort to improve raw read performance and at the same time enter
low power state at every possible chance.
For raw reads, it will keep the system powered on for a user specified
max time, this will help read multiple samples without power on/off
sequence.
When runtime pm is not enabled, then it fallbacks to current scheme
of on/off after each read.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
---
drivers/iio/accel/kxcjk-1013.c | 198 +++++++++++++++++++++++++++++++++--------
1 file changed, 160 insertions(+), 38 deletions(-)
diff --git a/drivers/iio/accel/kxcjk-1013.c b/drivers/iio/accel/kxcjk-1013.c
index bff5161..4912143 100644
--- a/drivers/iio/accel/kxcjk-1013.c
+++ b/drivers/iio/accel/kxcjk-1013.c
@@ -21,6 +21,8 @@
#include <linux/string.h>
#include <linux/acpi.h>
#include <linux/gpio/consumer.h>
+#include <linux/pm.h>
+#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
@@ -71,15 +73,21 @@
#define KXCJK1013_DATA_MASK_12_BIT 0x0FFF
#define KXCJK1013_MAX_STARTUP_TIME_US 100000
+#define KXCJK1013_SLEEP_DELAY_MS 2000
+static int kxcjk1013_power_off_delay_ms = KXCJK1013_SLEEP_DELAY_MS;
+module_param(kxcjk1013_power_off_delay_ms, int, 0644);
+MODULE_PARM_DESC(kxcjk1013_power_off_delay_ms,
+ "KXCJK1013 accelerometer power of delay in milli seconds.");
+
struct kxcjk1013_data {
struct i2c_client *client;
struct iio_trigger *trig;
bool trig_mode;
struct mutex mutex;
s16 buffer[8];
- int power_state;
u8 odr_bits;
bool active_high_intr;
+ bool trigger_on;
};
enum kxcjk1013_axis {
@@ -138,6 +146,25 @@ static int kxcjk1013_set_mode(struct kxcjk1013_data *data,
return 0;
}
+static int kxcjk1013_get_mode(struct kxcjk1013_data *data,
+ enum kxcjk1013_mode *mode)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, KXCJK1013_REG_CTRL1);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "Error reading reg_ctrl1\n");
+ return ret;
+ }
+
+ if (ret & KXCJK1013_REG_CTRL1_BIT_PC1)
+ *mode = OPERATION;
+ else
+ *mode = STANDBY;
+
+ return 0;
+}
+
static int kxcjk1013_chip_init(struct kxcjk1013_data *data)
{
int ret;
@@ -204,10 +231,53 @@ static int kxcjk1013_chip_init(struct kxcjk1013_data *data)
return 0;
}
+static int kxcjk1013_set_power_state(struct kxcjk1013_data *data, bool on)
+{
+ int ret;
+
+#ifdef CONFIG_PM_RUNTIME
+ if (on)
+ ret = pm_runtime_get_sync(&data->client->dev);
+ else {
+ pm_runtime_put_noidle(&data->client->dev);
+ ret = pm_schedule_suspend(&data->client->dev,
+ kxcjk1013_power_off_delay_ms);
+ }
+#else
+ if (on) {
+ ret = kxcjk1013_set_mode(data, OPERATION);
+ if (!ret) {
+ int sleep_val;
+
+ sleep_val = kxcjk1013_get_startup_times(data);
+ if (sleep_val < 20000)
+ usleep_range(sleep_val, 20000);
+ else
+ msleep_interruptible(sleep_val/1000);
+
+ }
+ } else
+ ret = kxcjk1013_set_mode(data, STANDBY);
+#endif
+
+ if (ret < 0) {
+ dev_err(&data->client->dev,
+ "Failed: kxcjk1013_set_power_state for %d\n", on);
+ return ret;
+ }
+
+ return 0;
+}
+
static int kxcjk1013_chip_setup_interrupt(struct kxcjk1013_data *data,
bool status)
{
int ret;
+ enum kxcjk1013_mode store_mode;
+
+ ret = kxcjk1013_get_mode(data, &store_mode);
+ if (ret < 0)
+ return ret;
/* This is requirement by spec to change state to STANDBY */
ret = kxcjk1013_set_mode(data, STANDBY);
@@ -250,7 +320,13 @@ static int kxcjk1013_chip_setup_interrupt(struct kxcjk1013_data *data,
return ret;
}
- return ret;
+ if (store_mode == OPERATION) {
+ ret = kxcjk1013_set_mode(data, OPERATION);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
}
static int kxcjk1013_convert_freq_to_bit(int val, int val2)
@@ -271,6 +347,11 @@ static int kxcjk1013_set_odr(struct kxcjk1013_data *data, int val, int val2)
{
int ret;
int odr_bits;
+ enum kxcjk1013_mode store_mode;
+
+ ret = kxcjk1013_get_mode(data, &store_mode);
+ if (ret < 0)
+ return ret;
odr_bits = kxcjk1013_convert_freq_to_bit(val, val2);
if (odr_bits < 0)
@@ -290,9 +371,7 @@ static int kxcjk1013_set_odr(struct kxcjk1013_data *data, int val, int val2)
data->odr_bits = odr_bits;
- /* Check, if the ODR is changed after data enable */
- if (data->power_state) {
- /* Set the state back to operation */
+ if (store_mode == OPERATION) {
ret = kxcjk1013_set_mode(data, OPERATION);
if (ret < 0)
return ret;
@@ -356,29 +435,25 @@ static int kxcjk1013_read_raw(struct iio_dev *indio_dev,
if (iio_buffer_enabled(indio_dev))
ret = -EBUSY;
else {
- int sleep_val;
-
- ret = kxcjk1013_set_mode(data, OPERATION);
+ ret = kxcjk1013_set_power_state(data, true);
if (ret < 0) {
mutex_unlock(&data->mutex);
return ret;
}
- ++data->power_state;
- sleep_val = kxcjk1013_get_startup_times(data);
- if (sleep_val < 20000)
- usleep_range(sleep_val, 20000);
- else
- msleep_interruptible(sleep_val/1000);
ret = kxcjk1013_get_acc_reg(data, chan->scan_index);
- if (--data->power_state == 0)
- kxcjk1013_set_mode(data, STANDBY);
+ if (ret < 0) {
+ kxcjk1013_set_power_state(data, false);
+ mutex_unlock(&data->mutex);
+ return ret;
+ }
+ *val = sign_extend32(ret >> 4, 11);
+ ret = kxcjk1013_set_power_state(data, false);
}
mutex_unlock(&data->mutex);
if (ret < 0)
return ret;
- *val = sign_extend32(ret >> 4, 11);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
@@ -520,20 +595,21 @@ static int kxcjk1013_data_rdy_trigger_set_state(struct iio_trigger *trig,
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct kxcjk1013_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (state && data->trigger_on)
+ return 0;
mutex_lock(&data->mutex);
- if (state) {
- kxcjk1013_chip_setup_interrupt(data, true);
- kxcjk1013_set_mode(data, OPERATION);
- ++data->power_state;
- } else {
- if (--data->power_state) {
+ ret = kxcjk1013_chip_setup_interrupt(data, state);
+ if (!ret) {
+ ret = kxcjk1013_set_power_state(data, state);
+ if (ret < 0) {
mutex_unlock(&data->mutex);
- return 0;
+ return ret;
}
- kxcjk1013_chip_setup_interrupt(data, false);
- kxcjk1013_set_mode(data, STANDBY);
}
+ data->trigger_on = state;
mutex_unlock(&data->mutex);
return 0;
@@ -660,14 +736,22 @@ static int kxcjk1013_probe(struct i2c_client *client,
}
}
- ret = devm_iio_device_register(&client->dev, indio_dev);
+ ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev, "unable to register iio device\n");
goto err_buffer_cleanup;
}
+ ret = pm_runtime_set_active(&client->dev);
+ if (ret)
+ goto err_iio_unregister;
+
+ pm_runtime_enable(&client->dev);
+
return 0;
+err_iio_unregister:
+ iio_device_unregister(indio_dev);
err_buffer_cleanup:
if (data->trig_mode)
iio_triggered_buffer_cleanup(indio_dev);
@@ -686,6 +770,12 @@ static int kxcjk1013_remove(struct i2c_client *client)
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct kxcjk1013_data *data = iio_priv(indio_dev);
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+ pm_runtime_put_noidle(&client->dev);
+
+ iio_device_unregister(indio_dev);
+
if (data->trig_mode) {
iio_triggered_buffer_cleanup(indio_dev);
iio_trigger_unregister(data->trig);
@@ -704,35 +794,67 @@ static int kxcjk1013_suspend(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct kxcjk1013_data *data = iio_priv(indio_dev);
+ int ret;
mutex_lock(&data->mutex);
- kxcjk1013_set_mode(data, STANDBY);
+ ret = kxcjk1013_set_mode(data, STANDBY);
mutex_unlock(&data->mutex);
- return 0;
+ return ret;
}
static int kxcjk1013_resume(struct device *dev)
{
struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
struct kxcjk1013_data *data = iio_priv(indio_dev);
+ int ret = 0;
mutex_lock(&data->mutex);
+ /* Check, if the suspend occured while active */
+ if (data->trigger_on)
+ ret = kxcjk1013_set_mode(data, OPERATION);
+ mutex_unlock(&data->mutex);
- if (data->power_state)
- kxcjk1013_set_mode(data, OPERATION);
+ return ret;
+}
+#endif
- mutex_unlock(&data->mutex);
+#ifdef CONFIG_PM_RUNTIME
+static int kxcjk1013_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct kxcjk1013_data *data = iio_priv(indio_dev);
- return 0;
+ return kxcjk1013_set_mode(data, STANDBY);
}
-static SIMPLE_DEV_PM_OPS(kxcjk1013_pm_ops, kxcjk1013_suspend, kxcjk1013_resume);
-#define KXCJK1013_PM_OPS (&kxcjk1013_pm_ops)
-#else
-#define KXCJK1013_PM_OPS NULL
+static int kxcjk1013_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct kxcjk1013_data *data = iio_priv(indio_dev);
+ int ret;
+ int sleep_val;
+
+ ret = kxcjk1013_set_mode(data, OPERATION);
+ if (ret < 0)
+ return ret;
+
+ sleep_val = kxcjk1013_get_startup_times(data);
+ if (sleep_val < 20000)
+ usleep_range(sleep_val, 20000);
+ else
+ msleep_interruptible(sleep_val/1000);
+
+ return 0;
+}
#endif
+static const struct dev_pm_ops kxcjk1013_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(kxcjk1013_suspend, kxcjk1013_resume)
+ SET_RUNTIME_PM_OPS(kxcjk1013_runtime_suspend,
+ kxcjk1013_runtime_resume, NULL)
+};
+
static const struct acpi_device_id kx_acpi_match[] = {
{"KXCJ1013", 0},
{ },
@@ -750,7 +872,7 @@ static struct i2c_driver kxcjk1013_driver = {
.driver = {
.name = KXCJK1013_DRV_NAME,
.acpi_match_table = ACPI_PTR(kx_acpi_match),
- .pm = KXCJK1013_PM_OPS,
+ .pm = &kxcjk1013_pm_ops,
},
.probe = kxcjk1013_probe,
.remove = kxcjk1013_remove,
--
1.7.11.7
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
