This is a note to let you know that I've just added the patch titled
media: rcar-csi2: Correct the selection of hsfreqrange
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
media-rcar-csi2-correct-the-selection-of-hsfreqrange.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit faa5b30a5098731bb77047d1d5137b54b6d4000f
Author: Suresh Udipi <sudipi@xxxxxxxxxxxxxx>
Date: Fri Aug 13 17:07:54 2021 +0200
media: rcar-csi2: Correct the selection of hsfreqrange
[ Upstream commit cee44d4fbacbbdfe62697ec94e76c6e4f726c5df ]
hsfreqrange should be chosen based on the calculated mbps which
is closer to the default bit rate and within the range as per
table[1]. But current calculation always selects first value which
is greater than or equal to the calculated mbps which may lead
to chosing a wrong range in some cases.
For example for 360 mbps for H3/M3N
Existing logic selects
Calculated value 360Mbps : Default 400Mbps Range [368.125 -433.125 mbps]
This hsfreqrange is out of range.
The logic is changed to get the default value which is closest to the
calculated value [1]
Calculated value 360Mbps : Default 350Mbps Range [320.625 -380.625 mpbs]
[1] specs r19uh0105ej0200-r-car-3rd-generation.pdf [Table 25.9]
Please note that According to Renesas in Table 25.9 the range for
220 default value is corrected as below
|Range (Mbps) | Default Bit rate (Mbps) |
-----------------------------------------------
| 197.125-244.125 | 220 |
-----------------------------------------------
Fixes: 769afd212b16 ("media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver")
Signed-off-by: Suresh Udipi <sudipi@xxxxxxxxxxxxxx>
Signed-off-by: Kazuyoshi Akiyama <akiyama@xxxxxxxxxxxxx>
Signed-off-by: Michael Rodin <mrodin@xxxxxxxxxxxxxx>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/media/platform/rcar-vin/rcar-csi2.c b/drivers/media/platform/rcar-vin/rcar-csi2.c
index d2d87a204e918..6fb8efcb40444 100644
--- a/drivers/media/platform/rcar-vin/rcar-csi2.c
+++ b/drivers/media/platform/rcar-vin/rcar-csi2.c
@@ -436,16 +436,23 @@ static int rcsi2_wait_phy_start(struct rcar_csi2 *priv,
static int rcsi2_set_phypll(struct rcar_csi2 *priv, unsigned int mbps)
{
const struct rcsi2_mbps_reg *hsfreq;
+ const struct rcsi2_mbps_reg *hsfreq_prev = NULL;
- for (hsfreq = priv->info->hsfreqrange; hsfreq->mbps != 0; hsfreq++)
+ for (hsfreq = priv->info->hsfreqrange; hsfreq->mbps != 0; hsfreq++) {
if (hsfreq->mbps >= mbps)
break;
+ hsfreq_prev = hsfreq;
+ }
if (!hsfreq->mbps) {
dev_err(priv->dev, "Unsupported PHY speed (%u Mbps)", mbps);
return -ERANGE;
}
+ if (hsfreq_prev &&
+ ((mbps - hsfreq_prev->mbps) <= (hsfreq->mbps - mbps)))
+ hsfreq = hsfreq_prev;
+
rcsi2_write(priv, PHYPLL_REG, PHYPLL_HSFREQRANGE(hsfreq->reg));
return 0;
