[PATCH 3/4] media: ov5647: Add support for non-continuous clock mode

From: Roman Kovalivskyi
Date: Mon Apr 13 2020 - 05:24:55 EST


From: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>

The driver was only supporting continuous clock mode
although this was not stated anywhere.
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@xxxxxxxxxxxxxxx>
Signed-off-by: Roman Kovalivskyi <roman.kovalivskyi@xxxxxxxxxxxxxxx>
---
drivers/media/i2c/ov5647.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/media/i2c/ov5647.c b/drivers/media/i2c/ov5647.c
index c39e3d20e3ef..8a1a515388e0 100644
--- 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;
+ unsigned int flags;
};

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->flags & V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK)
+ 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;

@@ -568,7 +576,7 @@ 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 device_node *np, struct ov5647 *sensor)
{
struct v4l2_fwnode_endpoint bus_cfg = { .bus_type = 0 };
struct device_node *ep;
@@ -581,6 +589,9 @@ static int ov5647_parse_dt(struct device_node *np)

ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &bus_cfg);

+ if (!ret)
+ sensor->flags = bus_cfg.bus.mipi_csi2.flags;
+
of_node_put(ep);
return ret;
}
@@ -599,7 +610,7 @@ 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(np, sensor);
if (ret) {
dev_err(dev, "DT parsing error: %d\n", ret);
return ret;
--
2.17.1