Re: [PATCH 2/2] media: qcom: camss: Restrict endpoint bus-type to D-PHY

From: Vladimir Zapolskiy
Date: Fri Dec 13 2024 - 06:03:13 EST


On 12/9/24 14:32, Bryan O'Donoghue wrote:
On 09/12/2024 12:01, Luca Weiss wrote:
Currently the Qualcomm CAMSS driver only supports D-PHY while the
hardware on most SoCs also supports C-PHY. Until this support is added,
check for D-PHY to make it somewhat explicit that C-PHY won't work.

Signed-off-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx>
---
drivers/media/platform/qcom/camss/camss.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/drivers/media/platform/qcom/camss/camss.c b/drivers/media/platform/qcom/camss/camss.c
index 9fb31f4c18adee886cd0bcf84438a8f27635e07f..b99af35074cdf6fa794a0d2f0d54ecf12ac354d9 100644
--- a/drivers/media/platform/qcom/camss/camss.c
+++ b/drivers/media/platform/qcom/camss/camss.c
@@ -1855,6 +1855,15 @@ static int camss_of_parse_endpoint_node(struct device *dev,
if (ret)
return ret;
+ /*
+ * Most SoCs support both D-PHY and C-PHY standards, but currently only
+ * D-PHY is supported in the driver.
+ */
+ if (vep.bus_type != V4L2_MBUS_CSI2_DPHY) {
+ dev_err(dev, "Unsupported bus type %d\n", vep.bus_type);
+ return -EINVAL;
+ }
+

Looks like it would break all old board dtbs, which is not just bad, but NAK.

V4L2_MBUS_UNKNOWN shall be properly handled without the risk of regressions.

csd->interface.csiphy_id = vep.base.port;
mipi_csi2 = &vep.bus.mipi_csi2;


Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@xxxxxxxxxx>


--
Best wishes,
Vladimir