From: Pratyush Yadav <p.yadav@xxxxxx> This resets the stream state machines and FIFOs, giving them a clean slate. On J721E if the streams are not reset before starting the capture, the captured frame gets wrapped around vertically on every run after the first. Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> Reviewed-by: Maxime Ripard <mripard@xxxxxxxxxx> Signed-off-by: Jai Luthra <j-luthra@xxxxxx> --- Changes from v8: - Simplify reset sequence, minimizing delays drivers/media/platform/cadence/cdns-csi2rx.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c index 933edec89520..b57e0c3b1944 100644 --- a/drivers/media/platform/cadence/cdns-csi2rx.c +++ b/drivers/media/platform/cadence/cdns-csi2rx.c @@ -40,6 +40,7 @@ #define CSI2RX_STREAM_BASE(n) (((n) + 1) * 0x100) #define CSI2RX_STREAM_CTRL_REG(n) (CSI2RX_STREAM_BASE(n) + 0x000) +#define CSI2RX_STREAM_CTRL_SOFT_RST BIT(4) #define CSI2RX_STREAM_CTRL_START BIT(0) #define CSI2RX_STREAM_DATA_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x008) @@ -134,12 +135,23 @@ struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev) static void csi2rx_reset(struct csi2rx_priv *csi2rx) { + unsigned int i; + + /* Reset module */ writel(CSI2RX_SOFT_RESET_PROTOCOL | CSI2RX_SOFT_RESET_FRONT, csi2rx->base + CSI2RX_SOFT_RESET_REG); + /* Reset individual streams. */ + for (i = 0; i < csi2rx->max_streams; i++) { + writel(CSI2RX_STREAM_CTRL_SOFT_RST, + csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); + } - udelay(10); + usleep_range(10, 20); + /* Clear resets */ writel(0, csi2rx->base + CSI2RX_SOFT_RESET_REG); + for (i = 0; i < csi2rx->max_streams; i++) + writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); } static int csi2rx_configure_ext_dphy(struct csi2rx_priv *csi2rx) -- 2.41.0