[PATCH AUTOSEL 4.9 38/98] gpu: ipu-v3: Fix CSI selection for VDIC

Sasha Levin
2018-10-25T14:13:23Z

From: Marek Vasut <marex@denx.de>

[ Upstream commit b7dfee2433576f1f030cb84cdb04b70f36554992 ]

The description of the CSI_SEL bit in the i.MX6 reference manual is
incorrect. It states "This bit defines which CSI is the input to the
IC. This bit is effective only if IC_INPUT is bit cleared".

>From experiment it was found this is in fact not correct. The CSI_SEL
bit selects which CSI is input to _both_ the VDIC _and_ the IC. If the
IC_INPUT bit is set so that the IC is receiving from the VDIC, the IC
ignores the CSI_SEL bit, but CSI_SEL still selects which CSI the VDIC
receives from in that case.

Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/ipu-v3/ipu-common.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/ipu-v3/ipu-common.c b/drivers/gpu/ipu-v3/ipu-common.c
index b9539f7c5e9a..99c813a4ec1f 100644
--- a/drivers/gpu/ipu-v3/ipu-common.c
+++ b/drivers/gpu/ipu-v3/ipu-common.c
@@ -715,15 +715,16 @@ void ipu_set_ic_src_mux(struct ipu_soc *ipu, int csi_id, bool vdi)
spin_lock_irqsave(&ipu->lock, flags);

val = ipu_cm_read(ipu, IPU_CONF);
- if (vdi) {
+ if (vdi)
val |= IPU_CONF_IC_INPUT;
- } else {
+ else
val &= ~IPU_CONF_IC_INPUT;
- if (csi_id == 1)
- val |= IPU_CONF_CSI_SEL;
- else
- val &= ~IPU_CONF_CSI_SEL;
- }
+
+ if (csi_id == 1)
+ val |= IPU_CONF_CSI_SEL;
+ else
+ val &= ~IPU_CONF_CSI_SEL;
+
ipu_cm_write(ipu, val, IPU_CONF);

spin_unlock_irqrestore(&ipu->lock, flags);
--
2.17.1