Re: [PATCH v10 12/18] media: cadence: csi2rx: Use the stream from route to get format

From: Rishikesh Donadkar

Date: Thu Jan 29 2026 - 23:08:18 EST



On 23/01/26 13:23, Tomi Valkeinen wrote:
Hi,
Hi Tomi,

On 21/01/2026 15:54, Rishikesh Donadkar wrote:
In multistream configurations, different streams can have different
formats. Update the driver to use the stream number from the routing
configuration when retrieving formats instead of hardcoding stream 0
or ignoring streams.

In csi2rx_configure_ext_dphy(), use the sink_stream from the first
route instead of always using stream 0.

In cdns_csi2rx_negotiate_ppc(), iterate through all active routes
for the requested pad and retrieve the format using both pad and
stream information.

Signed-off-by: Rishikesh Donadkar <r-donadkar@xxxxxx>
---
drivers/media/platform/cadence/cdns-csi2rx.c | 34 ++++++++++++++++----
1 file changed, 28 insertions(+), 6 deletions(-)
So if I understand this right, v9 was working by luck, as it was always
using stream 0 format (and expected stream 0 to be there)?


Yes, when I tested using IMX219 connected to the port 1 of the fpd-link board, I faced an issue where the v4l2_subdev_state_get_format() returned NULL when no stream was passed to it, here the default 0 was considered but the fpd-link driver which assigns stream number wrt ports assigned it as 1.


Two thoughts here:
- This should be merged to the previous patch, shouldn't it?


Yes, will do that

- Are you now testing with different resolutions, fps, etc on the
fpd-link ports?


I will test the v11 with multiple resolutions and formats. I will mention the tested ones in the cover letter


Rishikesh


Reviewed-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>

Tomi

diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
index 175366f889115..db9871fdbe3a4 100644
--- a/drivers/media/platform/cadence/cdns-csi2rx.c
+++ b/drivers/media/platform/cadence/cdns-csi2rx.c
@@ -279,6 +279,7 @@ static int csi2rx_configure_ext_dphy(struct csi2rx_priv *csi2rx)
struct v4l2_mbus_framefmt *framefmt;
struct v4l2_subdev_state *state;
const struct csi2rx_fmt *fmt;
+ struct v4l2_subdev_route *route;
int source_pad = csi2rx->source_pad;
struct media_pad *pad = &csi2rx->source_subdev->entity.pads[source_pad];
s64 link_freq;
@@ -296,7 +297,9 @@ static int csi2rx_configure_ext_dphy(struct csi2rx_priv *csi2rx)
if (state->routing.num_routes > 1) {
bpp = 0;
} else {
- framefmt = v4l2_subdev_state_get_format(state, CSI2RX_PAD_SINK, 0);
+ route = &state->routing.routes[0];
+ framefmt = v4l2_subdev_state_get_format(state, CSI2RX_PAD_SINK,
+ route->sink_stream);
if (!framefmt) {
dev_err(csi2rx->dev, "Did not find active sink format\n");
return -EINVAL;
@@ -706,25 +709,44 @@ int cdns_csi2rx_negotiate_ppc(struct v4l2_subdev *subdev, unsigned int pad,
{
struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev);
const struct csi2rx_fmt *csi_fmt;
+ struct v4l2_subdev_route *route;
struct v4l2_subdev_state *state;
struct v4l2_mbus_framefmt *fmt;
+ int ret = 0;
if (!ppc || pad < CSI2RX_PAD_SOURCE_STREAM0 || pad >= CSI2RX_PAD_MAX)
return -EINVAL;
state = v4l2_subdev_lock_and_get_active_state(subdev);
- fmt = v4l2_subdev_state_get_format(state, pad);
- csi_fmt = csi2rx_get_fmt_by_code(fmt->code);
+ /* Check all streams on requested pad */
+ for_each_active_route(&state->routing, route) {
+ if (route->source_pad != pad)
+ continue;
+
+ fmt = v4l2_subdev_state_get_format(state, route->source_pad,
+ route->source_stream);
+ if (!fmt) {
+ ret = -EPIPE;
+ *ppc = 1;
+ break;
+ }
- /* Reduce requested PPC if it is too high */
- *ppc = min(*ppc, csi_fmt->max_pixels);
+ csi_fmt = csi2rx_get_fmt_by_code(fmt->code);
+ if (!csi_fmt) {
+ ret = -EINVAL;
+ *ppc = 1;
+ break;
+ }
+ /* Reduce requested PPC if it is too high for this stream */
+ *ppc = min(*ppc, csi_fmt->max_pixels);
+ }
v4l2_subdev_unlock_state(state);
csi2rx->num_pixels[pad - CSI2RX_PAD_SOURCE_STREAM0] =
CSI2RX_STREAM_CFG_NUM_PIXELS(*ppc);
- return 0;
+ return ret;
}
EXPORT_SYMBOL_FOR_MODULES(cdns_csi2rx_negotiate_ppc, "j721e-csi2rx");