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;