media: ov5647: Add support for non-continuous clock mode

Add support for optional non-continuous clock mode to the ov5647
sensor driver.

Non-continuous clock saves a small amount of power and on some SoCs
is easier to interface with.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
Signed-off-by: Roman Kovalivskyi <roman.kovalivskyi@globallogic.com>
Signed-off-by: Jacopo Mondi <jacopo@jmondi.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
index 5dde138..ccb56f9 100644 (file)
--- a/drivers/media/i2c/ov5647.c
+++ b/drivers/media/i2c/ov5647.c
@@ -44,6 +44,7 @@
 #define PWDN_ACTIVE_DELAY_MS   20
 
 #define MIPI_CTRL00_CLOCK_LANE_GATE            BIT(5)
+#define MIPI_CTRL00_LINE_SYNC_ENABLE           BIT(4)
 #define MIPI_CTRL00_BUS_IDLE                   BIT(2)
 #define MIPI_CTRL00_CLOCK_LANE_DISABLE         BIT(0)
 
@@ -95,6 +96,7 @@ struct ov5647 {
        int                             power_count;
        struct clk                      *xclk;
        struct gpio_desc                *pwdn;
+       bool                            clock_ncont;
 };
 
 static inline struct ov5647 *to_state(struct v4l2_subdev *sd)
@@ -269,9 +271,15 @@ static int ov5647_set_virtual_channel(struct v4l2_subdev *sd, int channel)
 
 static int ov5647_stream_on(struct v4l2_subdev *sd)
 {
+       struct ov5647 *ov5647 = to_state(sd);
+       u8 val = MIPI_CTRL00_BUS_IDLE;
        int ret;
 
-       ret = ov5647_write(sd, OV5647_REG_MIPI_CTRL00, MIPI_CTRL00_BUS_IDLE);
+       if (ov5647->clock_ncont)
+               val |= MIPI_CTRL00_CLOCK_LANE_GATE |
+                      MIPI_CTRL00_LINE_SYNC_ENABLE;
+
+       ret = ov5647_write(sd, OV5647_REG_MIPI_CTRL00, val);
        if (ret < 0)
                return ret;
 
@@ -546,9 +554,11 @@ static const struct v4l2_subdev_internal_ops ov5647_subdev_internal_ops = {
        .open = ov5647_open,
 };
 
-static int ov5647_parse_dt(struct device_node *np)
+static int ov5647_parse_dt(struct ov5647 *sensor, struct device_node *np)
 {
-       struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
+       struct v4l2_fwnode_endpoint bus_cfg = {
+               .bus_type = V4L2_MBUS_CSI2_DPHY,
+       };
        struct device_node *ep;
 
        int ret;
@@ -558,7 +568,13 @@ static int ov5647_parse_dt(struct device_node *np)
                return -EINVAL;
 
        ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &bus_cfg);
+       if (ret)
+               goto out;
 
+       sensor->clock_ncont = bus_cfg.bus.mipi_csi2.flags &
+                             V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
+
+out:
        of_node_put(ep);
        return ret;
 }
@@ -577,7 +593,7 @@ static int ov5647_probe(struct i2c_client *client)
                return -ENOMEM;
 
        if (IS_ENABLED(CONFIG_OF) && np) {
-               ret = ov5647_parse_dt(np);
+               ret = ov5647_parse_dt(sensor, np);
                if (ret) {
                        dev_err(dev, "DT parsing error: %d\n", ret);
                        return ret;