[PATCH v2 1/1] reset: imx7: Correct polarity of MIPI CSI resets on i.MX8MQ

From: Robby Cai

Date: Fri Apr 17 2026 - 04:12:15 EST


On i.MX8MQ, the MIPI CSI reset lines are active-low and not self-clearing.
Writing '0' asserts reset and it remains asserted until explicitly
deasserted by software.

This driver previously treated the MIPI CSI reset signals as active-high,
which led to incorrect reset assert/deassert sequencing. This issue was
exposed by commit 6d79bb8fd2aa ("media: imx8mq-mipi-csi2: Explicitly
release reset").

Fix this by reflecting the correct reset polarity and ensuring proper
reset handling.

Fixes: c979dbf59987 ("reset: imx7: Add support for i.MX8MQ IP block variant")
Signed-off-by: Robby Cai <robby.cai@xxxxxxx>
---

Changes in v2:
- Drop the naming change in response to feedback from Krzysztof Kozlowski
- Refine the patch subject and commit message

Link to v1: https://lore.kernel.org/imx/20260331101331.1405588-1-robby.cai@xxxxxxx/

---
drivers/reset/reset-imx7.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/reset/reset-imx7.c b/drivers/reset/reset-imx7.c
index dd01fe11c5cb..a3cb8244d76a 100644
--- a/drivers/reset/reset-imx7.c
+++ b/drivers/reset/reset-imx7.c
@@ -236,6 +236,12 @@ static int imx8mq_reset_set(struct reset_controller_dev *rcdev,

case IMX8MQ_RESET_PCIE_CTRL_APPS_EN:
case IMX8MQ_RESET_PCIE2_CTRL_APPS_EN:
+ case IMX8MQ_RESET_MIPI_CSI1_CORE_RESET:
+ case IMX8MQ_RESET_MIPI_CSI1_PHY_REF_RESET:
+ case IMX8MQ_RESET_MIPI_CSI1_ESC_RESET:
+ case IMX8MQ_RESET_MIPI_CSI2_CORE_RESET:
+ case IMX8MQ_RESET_MIPI_CSI2_PHY_REF_RESET:
+ case IMX8MQ_RESET_MIPI_CSI2_ESC_RESET:
case IMX8MQ_RESET_MIPI_DSI_PCLK_RESET_N:
case IMX8MQ_RESET_MIPI_DSI_ESC_RESET_N:
case IMX8MQ_RESET_MIPI_DSI_DPI_RESET_N:
--
2.37.1