@@ -21,6 +21,7 @@
#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/io.h>
@@ -35,6 +36,13 @@
#define SENSOR_NAME "ov5647"
+/*
+ * From the datasheet, "20ms after PWDN goes low or 20ms after RESETB goes
+ * high if reset is inserted after PWDN goes high, host can access sensor's
+ * SCCB to initialize sensor."
+ */
+#define PWDN_ACTIVE_DELAY_MS 20
+
#define MIPI_CTRL00_CLOCK_LANE_GATE BIT(5)
#define MIPI_CTRL00_BUS_IDLE BIT(2)
#define MIPI_CTRL00_CLOCK_LANE_DISABLE BIT(0)
@@ -86,6 +94,7 @@ struct ov5647 {
unsigned int height;
int power_count;
struct clk *xclk;
+ struct gpio_desc *pwdn;
};
static inline struct ov5647 *to_state(struct v4l2_subdev *sd)
@@ -355,6 +364,11 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on)
if (on && !ov5647->power_count) {
dev_dbg(&client->dev, "OV5647 power on\n");
+ if (ov5647->pwdn) {
+ gpiod_set_value_cansleep(ov5647->pwdn, 0);
+ msleep(PWDN_ACTIVE_DELAY_MS);
+ }
+
ret = clk_prepare_enable(ov5647->xclk);
if (ret < 0) {
dev_err(&client->dev, "clk prepare enable failed\n");
@@ -392,6 +406,8 @@ static int ov5647_sensor_power(struct v4l2_subdev *sd, int on)
dev_dbg(&client->dev, "soft stby failed\n");
clk_disable_unprepare(ov5647->xclk);
+
+ gpiod_set_value_cansleep(ov5647->pwdn, 1);
}
/* Update the power count. */
@@ -581,6 +597,14 @@ static int ov5647_probe(struct i2c_client *client)
return -EINVAL;
}
+ /* Request the power down GPIO asserted */
+ sensor->pwdn = devm_gpiod_get_optional(&client->dev, "pwdn",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(sensor->pwdn)) {
+ dev_err(dev, "Failed to get 'pwdn' gpio\n");
+ return -EINVAL;
+ }
+
mutex_init(&sensor->lock);
sd = &sensor->sd;
@@ -594,7 +618,15 @@ static int ov5647_probe(struct i2c_client *client)
if (ret < 0)
goto mutex_remove;
+ if (sensor->pwdn) {
+ gpiod_set_value_cansleep(sensor->pwdn, 0);
+ msleep(PWDN_ACTIVE_DELAY_MS);
+ }
+
ret = ov5647_detect(sd);
+
+ gpiod_set_value_cansleep(sensor->pwdn, 1);
+
if (ret < 0)
goto error;