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path: root/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
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Diffstat (limited to 'drivers/iio/proximity/pulsedlight-lidar-lite-v2.c')
-rw-r--r--drivers/iio/proximity/pulsedlight-lidar-lite-v2.c151
1 files changed, 125 insertions, 26 deletions
diff --git a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
index e544fcfd5..db35e04a0 100644
--- a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
+++ b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
@@ -13,7 +13,7 @@
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
- * TODO: runtime pm, interrupt mode, and signal strength reporting
+ * TODO: interrupt mode, and signal strength reporting
*/
#include <linux/err.h>
@@ -21,6 +21,7 @@
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/module.h>
+#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
@@ -35,8 +36,11 @@
#define LIDAR_REG_STATUS_INVALID BIT(3)
#define LIDAR_REG_STATUS_READY BIT(0)
-#define LIDAR_REG_DATA_HBYTE 0x0f
-#define LIDAR_REG_DATA_LBYTE 0x10
+#define LIDAR_REG_DATA_HBYTE 0x0f
+#define LIDAR_REG_DATA_LBYTE 0x10
+#define LIDAR_REG_DATA_WORD_READ BIT(7)
+
+#define LIDAR_REG_PWR_CONTROL 0x65
#define LIDAR_DRV_NAME "lidar"
@@ -44,6 +48,9 @@ struct lidar_data {
struct iio_dev *indio_dev;
struct i2c_client *client;
+ int (*xfer)(struct lidar_data *data, u8 reg, u8 *val, int len);
+ int i2c_enabled;
+
u16 buffer[8]; /* 2 byte distance + 8 byte timestamp */
};
@@ -62,7 +69,28 @@ static const struct iio_chan_spec lidar_channels[] = {
IIO_CHAN_SOFT_TIMESTAMP(1),
};
-static int lidar_read_byte(struct lidar_data *data, int reg)
+static int lidar_i2c_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
+{
+ struct i2c_client *client = data->client;
+ struct i2c_msg msg[2];
+ int ret;
+
+ msg[0].addr = client->addr;
+ msg[0].flags = client->flags | I2C_M_STOP;
+ msg[0].len = 1;
+ msg[0].buf = (char *) &reg;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = client->flags | I2C_M_RD;
+ msg[1].len = len;
+ msg[1].buf = (char *) val;
+
+ ret = i2c_transfer(client->adapter, msg, 2);
+
+ return (ret == 2) ? 0 : -EIO;
+}
+
+static int lidar_smbus_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
{
struct i2c_client *client = data->client;
int ret;
@@ -72,17 +100,35 @@ static int lidar_read_byte(struct lidar_data *data, int reg)
* so in turn i2c_smbus_read_byte_data cannot be used
*/
- ret = i2c_smbus_write_byte(client, reg);
- if (ret < 0) {
- dev_err(&client->dev, "cannot write addr value");
- return ret;
+ while (len--) {
+ ret = i2c_smbus_write_byte(client, reg++);
+ if (ret < 0) {
+ dev_err(&client->dev, "cannot write addr value");
+ return ret;
+ }
+
+ ret = i2c_smbus_read_byte(client);
+ if (ret < 0) {
+ dev_err(&client->dev, "cannot read data value");
+ return ret;
+ }
+
+ *(val++) = ret;
}
- ret = i2c_smbus_read_byte(client);
+ return 0;
+}
+
+static int lidar_read_byte(struct lidar_data *data, u8 reg)
+{
+ int ret;
+ u8 val;
+
+ ret = data->xfer(data, reg, &val, 1);
if (ret < 0)
- dev_err(&client->dev, "cannot read data value");
+ return ret;
- return ret;
+ return val;
}
static inline int lidar_write_control(struct lidar_data *data, int val)
@@ -90,24 +136,22 @@ static inline int lidar_write_control(struct lidar_data *data, int val)
return i2c_smbus_write_byte_data(data->client, LIDAR_REG_CONTROL, val);
}
-static int lidar_read_measurement(struct lidar_data *data, u16 *reg)
+static inline int lidar_write_power(struct lidar_data *data, int val)
{
- int ret;
- int val;
-
- ret = lidar_read_byte(data, LIDAR_REG_DATA_HBYTE);
- if (ret < 0)
- return ret;
- val = ret << 8;
+ return i2c_smbus_write_byte_data(data->client,
+ LIDAR_REG_PWR_CONTROL, val);
+}
- ret = lidar_read_byte(data, LIDAR_REG_DATA_LBYTE);
- if (ret < 0)
- return ret;
+static int lidar_read_measurement(struct lidar_data *data, u16 *reg)
+{
+ int ret = data->xfer(data, LIDAR_REG_DATA_HBYTE |
+ (data->i2c_enabled ? LIDAR_REG_DATA_WORD_READ : 0),
+ (u8 *) reg, 2);
- val |= ret;
- *reg = val;
+ if (!ret)
+ *reg = be16_to_cpu(*reg);
- return 0;
+ return ret;
}
static int lidar_get_measurement(struct lidar_data *data, u16 *reg)
@@ -116,6 +160,8 @@ static int lidar_get_measurement(struct lidar_data *data, u16 *reg)
int tries = 10;
int ret;
+ pm_runtime_get_sync(&client->dev);
+
/* start sample */
ret = lidar_write_control(data, LIDAR_REG_CONTROL_ACQUIRE);
if (ret < 0) {
@@ -144,6 +190,8 @@ static int lidar_get_measurement(struct lidar_data *data, u16 *reg)
}
ret = -EIO;
}
+ pm_runtime_mark_last_busy(&client->dev);
+ pm_runtime_put_autosuspend(&client->dev);
return ret;
}
@@ -221,6 +269,16 @@ static int lidar_probe(struct i2c_client *client,
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
+ data = iio_priv(indio_dev);
+
+ if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ data->xfer = lidar_i2c_xfer;
+ data->i2c_enabled = 1;
+ } else if (i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE))
+ data->xfer = lidar_smbus_xfer;
+ else
+ return -ENOTSUPP;
indio_dev->info = &lidar_info;
indio_dev->name = LIDAR_DRV_NAME;
@@ -228,7 +286,6 @@ static int lidar_probe(struct i2c_client *client,
indio_dev->num_channels = ARRAY_SIZE(lidar_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
- data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
@@ -243,6 +300,17 @@ static int lidar_probe(struct i2c_client *client,
if (ret)
goto error_unreg_buffer;
+ pm_runtime_set_autosuspend_delay(&client->dev, 1000);
+ pm_runtime_use_autosuspend(&client->dev);
+
+ ret = pm_runtime_set_active(&client->dev);
+ if (ret)
+ goto error_unreg_buffer;
+ pm_runtime_enable(&client->dev);
+
+ pm_runtime_mark_last_busy(&client->dev);
+ pm_runtime_idle(&client->dev);
+
return 0;
error_unreg_buffer:
@@ -258,6 +326,9 @@ static int lidar_remove(struct i2c_client *client)
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
+ pm_runtime_disable(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+
return 0;
}
@@ -273,10 +344,38 @@ static const struct of_device_id lidar_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, lidar_dt_ids);
+#ifdef CONFIG_PM
+static int lidar_pm_runtime_suspend(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct lidar_data *data = iio_priv(indio_dev);
+
+ return lidar_write_power(data, 0x0f);
+}
+
+static int lidar_pm_runtime_resume(struct device *dev)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+ struct lidar_data *data = iio_priv(indio_dev);
+ int ret = lidar_write_power(data, 0);
+
+ /* regulator and FPGA needs settling time */
+ usleep_range(15000, 20000);
+
+ return ret;
+}
+#endif
+
+static const struct dev_pm_ops lidar_pm_ops = {
+ SET_RUNTIME_PM_OPS(lidar_pm_runtime_suspend,
+ lidar_pm_runtime_resume, NULL)
+};
+
static struct i2c_driver lidar_driver = {
.driver = {
.name = LIDAR_DRV_NAME,
.of_match_table = of_match_ptr(lidar_dt_ids),
+ .pm = &lidar_pm_ops,
},
.probe = lidar_probe,
.remove = lidar_remove,