diff mbox series

[1/4] media: camss: sm8250: Virtual channels for CSID

Message ID 20220926142505.1827-2-quic_mmitkov@quicinc.com (mailing list archive)
State Superseded
Headers show
Series media: camss: sm8250: Virtual channels support for SM8250 | expand

Commit Message

Milen Mitkov (Consultant) Sept. 26, 2022, 2:25 p.m. UTC
From: Milen Mitkov <quic_mmitkov@quicinc.com>

CSID hardware on SM8250 can demux up to 4 simultaneous streams
based on virtual channel (vc) or datatype (dt).
The CSID subdevice entity now has 4 source ports that can be
enabled/disabled and thus can control which virtual channels
are enabled. Datatype demuxing not tested.

The implicit propagation of port formats has been removed
(e.g. previously setting sink port format would set the same format
to source port), because the source port is now not guaranteed to
follow the same  format as the sink port.
So port formats have to be set explicitly.

CSID's s_stream is called when any stream is started or stopped.
It will call configure_streams() that will rewrite IRQ settings to HW.
When multiple streams are running simultaneously there is an issue
when writing IRQ settings for one stream while another is still
running, thus avoid re-writing settings if they were not changed
in link setup, or by fully powering off the CSID hardware.

Signed-off-by: Milen Mitkov <quic_mmitkov@quicinc.com>
---
 .../platform/qcom/camss/camss-csid-gen2.c     | 55 ++++++++++++-------
 .../media/platform/qcom/camss/camss-csid.c    | 41 ++++++++------
 .../media/platform/qcom/camss/camss-csid.h    | 11 +++-
 3 files changed, 68 insertions(+), 39 deletions(-)

Comments

Robert Foss Oct. 4, 2022, 9:33 a.m. UTC | #1
Hey Milen,

Thanks for submitting this series.

On Mon, 26 Sept 2022 at 16:25, <quic_mmitkov@quicinc.com> wrote:
>
> From: Milen Mitkov <quic_mmitkov@quicinc.com>
>
> CSID hardware on SM8250 can demux up to 4 simultaneous streams
> based on virtual channel (vc) or datatype (dt).
> The CSID subdevice entity now has 4 source ports that can be
> enabled/disabled and thus can control which virtual channels
> are enabled. Datatype demuxing not tested.
>
> The implicit propagation of port formats has been removed
> (e.g. previously setting sink port format would set the same format
> to source port), because the source port is now not guaranteed to
> follow the same  format as the sink port.
> So port formats have to be set explicitly.
>
> CSID's s_stream is called when any stream is started or stopped.
> It will call configure_streams() that will rewrite IRQ settings to HW.
> When multiple streams are running simultaneously there is an issue
> when writing IRQ settings for one stream while another is still
> running, thus avoid re-writing settings if they were not changed
> in link setup, or by fully powering off the CSID hardware.
>
> Signed-off-by: Milen Mitkov <quic_mmitkov@quicinc.com>
> ---
>  .../platform/qcom/camss/camss-csid-gen2.c     | 55 ++++++++++++-------
>  .../media/platform/qcom/camss/camss-csid.c    | 41 ++++++++------
>  .../media/platform/qcom/camss/camss-csid.h    | 11 +++-
>  3 files changed, 68 insertions(+), 39 deletions(-)
>
> diff --git a/drivers/media/platform/qcom/camss/camss-csid-gen2.c b/drivers/media/platform/qcom/camss/camss-csid-gen2.c
> index 2031bde13a93..feb0f2ba982c 100644
> --- a/drivers/media/platform/qcom/camss/camss-csid-gen2.c
> +++ b/drivers/media/platform/qcom/camss/camss-csid-gen2.c
> @@ -334,13 +334,14 @@ static const struct csid_format csid_formats[] = {
>         },
>  };
>
> -static void csid_configure_stream(struct csid_device *csid, u8 enable)
> +static void __csid_configure_stream(struct csid_device *csid, u8 enable, u8 channel)
>  {
>         struct csid_testgen_config *tg = &csid->testgen;
>         u32 val;
>         u32 phy_sel = 0;
>         u8 lane_cnt = csid->phy.lane_cnt;
> -       struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_SRC];
> +       /* Source pads matching RDI channels on hardware. Pad 1 -> RDI0, Pad 2 -> RDI1, etc. */
> +       struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_FIRST_SRC + channel];
>         const struct csid_format *format = csid_get_fmt_entry(csid->formats, csid->nformats,
>                                                               input_format->code);
>
> @@ -351,8 +352,8 @@ static void csid_configure_stream(struct csid_device *csid, u8 enable)
>                 phy_sel = csid->phy.csiphy_id;
>
>         if (enable) {
> -               u8 vc = 0; /* Virtual Channel 0 */
> -               u8 dt_id = vc * 4;
> +               u8 vc = channel; /* mapping between virtual channel and RDIn index */

Is there any reason for having two variables (vc & channel)
representing the same thing? If not, let's keep just keep vc.

> +               u8 dt_id = vc;
>
>                 if (tg->enabled) {
>                         /* Config Test Generator */
> @@ -395,42 +396,42 @@ static void csid_configure_stream(struct csid_device *csid, u8 enable)
>                 val |= format->data_type << RDI_CFG0_DATA_TYPE;
>                 val |= vc << RDI_CFG0_VIRTUAL_CHANNEL;
>                 val |= dt_id << RDI_CFG0_DT_ID;
> -               writel_relaxed(val, csid->base + CSID_RDI_CFG0(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_CFG0(channel));
>
>                 /* CSID_TIMESTAMP_STB_POST_IRQ */
>                 val = 2 << RDI_CFG1_TIMESTAMP_STB_SEL;
> -               writel_relaxed(val, csid->base + CSID_RDI_CFG1(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_CFG1(channel));
>
>                 val = 1;
> -               writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PERIOD(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PERIOD(channel));
>
>                 val = 0;
> -               writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PATTERN(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PATTERN(channel));
>
>                 val = 1;
> -               writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(channel));
>
>                 val = 0;
> -               writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(channel));
>
>                 val = 1;
> -               writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PERIOD(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PERIOD(channel));
>
>                 val = 0;
> -               writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PATTERN(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PATTERN(channel));
>
>                 val = 1;
> -               writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PERIOD(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PERIOD(channel));
>
>                 val = 0;
> -               writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PATTERN(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PATTERN(channel));
>
>                 val = 0;
> -               writel_relaxed(val, csid->base + CSID_RDI_CTRL(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_CTRL(channel));
>
> -               val = readl_relaxed(csid->base + CSID_RDI_CFG0(0));
> +               val = readl_relaxed(csid->base + CSID_RDI_CFG0(channel));
>                 val |=  1 << RDI_CFG0_ENABLE;
> -               writel_relaxed(val, csid->base + CSID_RDI_CFG0(0));
> +               writel_relaxed(val, csid->base + CSID_RDI_CFG0(channel));
>         }
>
>         if (tg->enabled) {
> @@ -456,7 +457,16 @@ static void csid_configure_stream(struct csid_device *csid, u8 enable)
>                 val = HALT_CMD_RESUME_AT_FRAME_BOUNDARY << RDI_CTRL_HALT_CMD;
>         else
>                 val = HALT_CMD_HALT_AT_FRAME_BOUNDARY << RDI_CTRL_HALT_CMD;
> -       writel_relaxed(val, csid->base + CSID_RDI_CTRL(0));
> +       writel_relaxed(val, csid->base + CSID_RDI_CTRL(channel));
> +}
> +
> +static void csid_configure_stream(struct csid_device *csid, u8 enable)
> +{
> +       u8 i;
> +       /* Loop through all enabled VCs and configure stream for each */
> +       for (i = 0; i < MSM_CSID_MAX_SRC_STREAMS; i++)
> +               if (csid->phy.en_vc & BIT(i))
> +                       __csid_configure_stream(csid, enable, i);
>  }
>
>  static int csid_configure_testgen_pattern(struct csid_device *csid, s32 val)
> @@ -502,6 +512,7 @@ static irqreturn_t csid_isr(int irq, void *dev)
>         struct csid_device *csid = dev;
>         u32 val;
>         u8 reset_done;
> +       int i;
>
>         val = readl_relaxed(csid->base + CSID_TOP_IRQ_STATUS);
>         writel_relaxed(val, csid->base + CSID_TOP_IRQ_CLEAR);
> @@ -510,8 +521,12 @@ static irqreturn_t csid_isr(int irq, void *dev)
>         val = readl_relaxed(csid->base + CSID_CSI2_RX_IRQ_STATUS);
>         writel_relaxed(val, csid->base + CSID_CSI2_RX_IRQ_CLEAR);
>
> -       val = readl_relaxed(csid->base + CSID_CSI2_RDIN_IRQ_STATUS(0));
> -       writel_relaxed(val, csid->base + CSID_CSI2_RDIN_IRQ_CLEAR(0));
> +       /* Read and clear IRQ status for each enabled RDI channel */
> +       for (i = 0; i < MSM_CSID_MAX_SRC_STREAMS; i++)
> +               if (csid->phy.en_vc & BIT(i)) {
> +                       val = readl_relaxed(csid->base + CSID_CSI2_RDIN_IRQ_STATUS(i));
> +                       writel_relaxed(val, csid->base + CSID_CSI2_RDIN_IRQ_CLEAR(i));
> +               }
>
>         val = 1 << IRQ_CMD_CLEAR;
>         writel_relaxed(val, csid->base + CSID_IRQ_CMD);
> diff --git a/drivers/media/platform/qcom/camss/camss-csid.c b/drivers/media/platform/qcom/camss/camss-csid.c
> index 88f188e0f750..fdb636f70010 100644
> --- a/drivers/media/platform/qcom/camss/camss-csid.c
> +++ b/drivers/media/platform/qcom/camss/camss-csid.c
> @@ -209,6 +209,8 @@ static int csid_set_power(struct v4l2_subdev *sd, int on)
>                 }
>
>                 csid->ops->hw_version(csid);
> +
> +               csid->phy.need_vc_update = true;
>         } else {
>                 disable_irq(csid->irq);
>                 camss_disable_clocks(csid->nclocks, csid->clock);
> @@ -249,7 +251,10 @@ static int csid_set_stream(struct v4l2_subdev *sd, int enable)
>                         return -ENOLINK;
>         }
>
> -       csid->ops->configure_stream(csid, enable);
> +       if (csid->phy.need_vc_update) {
> +               csid->ops->configure_stream(csid, enable);
> +               csid->phy.need_vc_update = false;
> +       }
>
>         return 0;
>  }
> @@ -468,16 +473,6 @@ static int csid_set_format(struct v4l2_subdev *sd,
>         csid_try_format(csid, sd_state, fmt->pad, &fmt->format, fmt->which);
>         *format = fmt->format;
>
> -       /* Propagate the format from sink to source */
> -       if (fmt->pad == MSM_CSID_PAD_SINK) {
> -               format = __csid_get_format(csid, sd_state, MSM_CSID_PAD_SRC,
> -                                          fmt->which);
> -
> -               *format = fmt->format;
> -               csid_try_format(csid, sd_state, MSM_CSID_PAD_SRC, format,
> -                               fmt->which);
> -       }
> -
>         return 0;
>  }
>
> @@ -738,7 +733,6 @@ static int csid_link_setup(struct media_entity *entity,
>                 struct csid_device *csid;
>                 struct csiphy_device *csiphy;
>                 struct csiphy_lanes_cfg *lane_cfg;
> -               struct v4l2_subdev_format format = { 0 };
>
>                 sd = media_entity_to_v4l2_subdev(entity);
>                 csid = v4l2_get_subdevdata(sd);
> @@ -761,11 +755,22 @@ static int csid_link_setup(struct media_entity *entity,
>                 lane_cfg = &csiphy->cfg.csi2->lane_cfg;
>                 csid->phy.lane_cnt = lane_cfg->num_data;
>                 csid->phy.lane_assign = csid_get_lane_assign(lane_cfg);
> +       }
> +       /* Decide which virtual channels to enable based on which source pads are enabled */
> +       if (local->flags & MEDIA_PAD_FL_SOURCE) {
> +               struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
> +               struct csid_device *csid = v4l2_get_subdevdata(sd);
> +               struct device *dev = csid->camss->dev;
> +
> +               if (flags & MEDIA_LNK_FL_ENABLED)
> +                       csid->phy.en_vc |= BIT(local->index - 1);
> +               else
> +                       csid->phy.en_vc &= ~BIT(local->index - 1);
>
> -               /* Reset format on source pad to sink pad format */
> -               format.pad = MSM_CSID_PAD_SRC;
> -               format.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> -               csid_set_format(&csid->subdev, NULL, &format);
> +               csid->phy.need_vc_update = true;
> +
> +               dev_dbg(dev, "%s: Enabled CSID virtual channels mask 0x%x\n",
> +                       __func__, csid->phy.en_vc);
>         }
>
>         return 0;
> @@ -816,6 +821,7 @@ int msm_csid_register_entity(struct csid_device *csid,
>         struct v4l2_subdev *sd = &csid->subdev;
>         struct media_pad *pads = csid->pads;
>         struct device *dev = csid->camss->dev;
> +       int i;
>         int ret;
>
>         v4l2_subdev_init(sd, &csid_v4l2_ops);
> @@ -852,7 +858,8 @@ int msm_csid_register_entity(struct csid_device *csid,
>         }
>
>         pads[MSM_CSID_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
> -       pads[MSM_CSID_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
> +       for (i = MSM_CSID_PAD_FIRST_SRC; i < MSM_CSID_PADS_NUM; ++i)
> +               pads[i].flags = MEDIA_PAD_FL_SOURCE;
>
>         sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
>         sd->entity.ops = &csid_media_ops;
> diff --git a/drivers/media/platform/qcom/camss/camss-csid.h b/drivers/media/platform/qcom/camss/camss-csid.h
> index f06040e44c51..d4b48432a097 100644
> --- a/drivers/media/platform/qcom/camss/camss-csid.h
> +++ b/drivers/media/platform/qcom/camss/camss-csid.h
> @@ -19,8 +19,13 @@
>  #include <media/v4l2-subdev.h>
>
>  #define MSM_CSID_PAD_SINK 0
> -#define MSM_CSID_PAD_SRC 1
> -#define MSM_CSID_PADS_NUM 2
> +#define MSM_CSID_PAD_FIRST_SRC 1
> +#define MSM_CSID_PADS_NUM 5
> +
> +#define MSM_CSID_PAD_SRC (MSM_CSID_PAD_FIRST_SRC)
> +
> +/* CSID hardware can demultiplex up to 4 outputs */
> +#define MSM_CSID_MAX_SRC_STREAMS       4
>
>  #define DATA_TYPE_EMBEDDED_DATA_8BIT   0x12
>  #define DATA_TYPE_YUV420_8BIT          0x18
> @@ -81,6 +86,8 @@ struct csid_phy_config {
>         u8 csiphy_id;
>         u8 lane_cnt;
>         u32 lane_assign;
> +       u32 en_vc;
> +       u8 need_vc_update;
>  };
>
>  struct csid_device;
> --
> 2.37.3q
>

With the above fixed, please add my r-b.

Reviewed-by: Robert Foss <robert.foss@linaro.org>
diff mbox series

Patch

diff --git a/drivers/media/platform/qcom/camss/camss-csid-gen2.c b/drivers/media/platform/qcom/camss/camss-csid-gen2.c
index 2031bde13a93..feb0f2ba982c 100644
--- a/drivers/media/platform/qcom/camss/camss-csid-gen2.c
+++ b/drivers/media/platform/qcom/camss/camss-csid-gen2.c
@@ -334,13 +334,14 @@  static const struct csid_format csid_formats[] = {
 	},
 };
 
-static void csid_configure_stream(struct csid_device *csid, u8 enable)
+static void __csid_configure_stream(struct csid_device *csid, u8 enable, u8 channel)
 {
 	struct csid_testgen_config *tg = &csid->testgen;
 	u32 val;
 	u32 phy_sel = 0;
 	u8 lane_cnt = csid->phy.lane_cnt;
-	struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_SRC];
+	/* Source pads matching RDI channels on hardware. Pad 1 -> RDI0, Pad 2 -> RDI1, etc. */
+	struct v4l2_mbus_framefmt *input_format = &csid->fmt[MSM_CSID_PAD_FIRST_SRC + channel];
 	const struct csid_format *format = csid_get_fmt_entry(csid->formats, csid->nformats,
 							      input_format->code);
 
@@ -351,8 +352,8 @@  static void csid_configure_stream(struct csid_device *csid, u8 enable)
 		phy_sel = csid->phy.csiphy_id;
 
 	if (enable) {
-		u8 vc = 0; /* Virtual Channel 0 */
-		u8 dt_id = vc * 4;
+		u8 vc = channel; /* mapping between virtual channel and RDIn index */
+		u8 dt_id = vc;
 
 		if (tg->enabled) {
 			/* Config Test Generator */
@@ -395,42 +396,42 @@  static void csid_configure_stream(struct csid_device *csid, u8 enable)
 		val |= format->data_type << RDI_CFG0_DATA_TYPE;
 		val |= vc << RDI_CFG0_VIRTUAL_CHANNEL;
 		val |= dt_id << RDI_CFG0_DT_ID;
-		writel_relaxed(val, csid->base + CSID_RDI_CFG0(0));
+		writel_relaxed(val, csid->base + CSID_RDI_CFG0(channel));
 
 		/* CSID_TIMESTAMP_STB_POST_IRQ */
 		val = 2 << RDI_CFG1_TIMESTAMP_STB_SEL;
-		writel_relaxed(val, csid->base + CSID_RDI_CFG1(0));
+		writel_relaxed(val, csid->base + CSID_RDI_CFG1(channel));
 
 		val = 1;
-		writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PERIOD(0));
+		writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PERIOD(channel));
 
 		val = 0;
-		writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PATTERN(0));
+		writel_relaxed(val, csid->base + CSID_RDI_FRM_DROP_PATTERN(channel));
 
 		val = 1;
-		writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(0));
+		writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PERIOD(channel));
 
 		val = 0;
-		writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(0));
+		writel_relaxed(val, csid->base + CSID_RDI_IRQ_SUBSAMPLE_PATTERN(channel));
 
 		val = 1;
-		writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PERIOD(0));
+		writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PERIOD(channel));
 
 		val = 0;
-		writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PATTERN(0));
+		writel_relaxed(val, csid->base + CSID_RDI_RPP_PIX_DROP_PATTERN(channel));
 
 		val = 1;
-		writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PERIOD(0));
+		writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PERIOD(channel));
 
 		val = 0;
-		writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PATTERN(0));
+		writel_relaxed(val, csid->base + CSID_RDI_RPP_LINE_DROP_PATTERN(channel));
 
 		val = 0;
-		writel_relaxed(val, csid->base + CSID_RDI_CTRL(0));
+		writel_relaxed(val, csid->base + CSID_RDI_CTRL(channel));
 
-		val = readl_relaxed(csid->base + CSID_RDI_CFG0(0));
+		val = readl_relaxed(csid->base + CSID_RDI_CFG0(channel));
 		val |=  1 << RDI_CFG0_ENABLE;
-		writel_relaxed(val, csid->base + CSID_RDI_CFG0(0));
+		writel_relaxed(val, csid->base + CSID_RDI_CFG0(channel));
 	}
 
 	if (tg->enabled) {
@@ -456,7 +457,16 @@  static void csid_configure_stream(struct csid_device *csid, u8 enable)
 		val = HALT_CMD_RESUME_AT_FRAME_BOUNDARY << RDI_CTRL_HALT_CMD;
 	else
 		val = HALT_CMD_HALT_AT_FRAME_BOUNDARY << RDI_CTRL_HALT_CMD;
-	writel_relaxed(val, csid->base + CSID_RDI_CTRL(0));
+	writel_relaxed(val, csid->base + CSID_RDI_CTRL(channel));
+}
+
+static void csid_configure_stream(struct csid_device *csid, u8 enable)
+{
+	u8 i;
+	/* Loop through all enabled VCs and configure stream for each */
+	for (i = 0; i < MSM_CSID_MAX_SRC_STREAMS; i++)
+		if (csid->phy.en_vc & BIT(i))
+			__csid_configure_stream(csid, enable, i);
 }
 
 static int csid_configure_testgen_pattern(struct csid_device *csid, s32 val)
@@ -502,6 +512,7 @@  static irqreturn_t csid_isr(int irq, void *dev)
 	struct csid_device *csid = dev;
 	u32 val;
 	u8 reset_done;
+	int i;
 
 	val = readl_relaxed(csid->base + CSID_TOP_IRQ_STATUS);
 	writel_relaxed(val, csid->base + CSID_TOP_IRQ_CLEAR);
@@ -510,8 +521,12 @@  static irqreturn_t csid_isr(int irq, void *dev)
 	val = readl_relaxed(csid->base + CSID_CSI2_RX_IRQ_STATUS);
 	writel_relaxed(val, csid->base + CSID_CSI2_RX_IRQ_CLEAR);
 
-	val = readl_relaxed(csid->base + CSID_CSI2_RDIN_IRQ_STATUS(0));
-	writel_relaxed(val, csid->base + CSID_CSI2_RDIN_IRQ_CLEAR(0));
+	/* Read and clear IRQ status for each enabled RDI channel */
+	for (i = 0; i < MSM_CSID_MAX_SRC_STREAMS; i++)
+		if (csid->phy.en_vc & BIT(i)) {
+			val = readl_relaxed(csid->base + CSID_CSI2_RDIN_IRQ_STATUS(i));
+			writel_relaxed(val, csid->base + CSID_CSI2_RDIN_IRQ_CLEAR(i));
+		}
 
 	val = 1 << IRQ_CMD_CLEAR;
 	writel_relaxed(val, csid->base + CSID_IRQ_CMD);
diff --git a/drivers/media/platform/qcom/camss/camss-csid.c b/drivers/media/platform/qcom/camss/camss-csid.c
index 88f188e0f750..fdb636f70010 100644
--- a/drivers/media/platform/qcom/camss/camss-csid.c
+++ b/drivers/media/platform/qcom/camss/camss-csid.c
@@ -209,6 +209,8 @@  static int csid_set_power(struct v4l2_subdev *sd, int on)
 		}
 
 		csid->ops->hw_version(csid);
+
+		csid->phy.need_vc_update = true;
 	} else {
 		disable_irq(csid->irq);
 		camss_disable_clocks(csid->nclocks, csid->clock);
@@ -249,7 +251,10 @@  static int csid_set_stream(struct v4l2_subdev *sd, int enable)
 			return -ENOLINK;
 	}
 
-	csid->ops->configure_stream(csid, enable);
+	if (csid->phy.need_vc_update) {
+		csid->ops->configure_stream(csid, enable);
+		csid->phy.need_vc_update = false;
+	}
 
 	return 0;
 }
@@ -468,16 +473,6 @@  static int csid_set_format(struct v4l2_subdev *sd,
 	csid_try_format(csid, sd_state, fmt->pad, &fmt->format, fmt->which);
 	*format = fmt->format;
 
-	/* Propagate the format from sink to source */
-	if (fmt->pad == MSM_CSID_PAD_SINK) {
-		format = __csid_get_format(csid, sd_state, MSM_CSID_PAD_SRC,
-					   fmt->which);
-
-		*format = fmt->format;
-		csid_try_format(csid, sd_state, MSM_CSID_PAD_SRC, format,
-				fmt->which);
-	}
-
 	return 0;
 }
 
@@ -738,7 +733,6 @@  static int csid_link_setup(struct media_entity *entity,
 		struct csid_device *csid;
 		struct csiphy_device *csiphy;
 		struct csiphy_lanes_cfg *lane_cfg;
-		struct v4l2_subdev_format format = { 0 };
 
 		sd = media_entity_to_v4l2_subdev(entity);
 		csid = v4l2_get_subdevdata(sd);
@@ -761,11 +755,22 @@  static int csid_link_setup(struct media_entity *entity,
 		lane_cfg = &csiphy->cfg.csi2->lane_cfg;
 		csid->phy.lane_cnt = lane_cfg->num_data;
 		csid->phy.lane_assign = csid_get_lane_assign(lane_cfg);
+	}
+	/* Decide which virtual channels to enable based on which source pads are enabled */
+	if (local->flags & MEDIA_PAD_FL_SOURCE) {
+		struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+		struct csid_device *csid = v4l2_get_subdevdata(sd);
+		struct device *dev = csid->camss->dev;
+
+		if (flags & MEDIA_LNK_FL_ENABLED)
+			csid->phy.en_vc |= BIT(local->index - 1);
+		else
+			csid->phy.en_vc &= ~BIT(local->index - 1);
 
-		/* Reset format on source pad to sink pad format */
-		format.pad = MSM_CSID_PAD_SRC;
-		format.which = V4L2_SUBDEV_FORMAT_ACTIVE;
-		csid_set_format(&csid->subdev, NULL, &format);
+		csid->phy.need_vc_update = true;
+
+		dev_dbg(dev, "%s: Enabled CSID virtual channels mask 0x%x\n",
+			__func__, csid->phy.en_vc);
 	}
 
 	return 0;
@@ -816,6 +821,7 @@  int msm_csid_register_entity(struct csid_device *csid,
 	struct v4l2_subdev *sd = &csid->subdev;
 	struct media_pad *pads = csid->pads;
 	struct device *dev = csid->camss->dev;
+	int i;
 	int ret;
 
 	v4l2_subdev_init(sd, &csid_v4l2_ops);
@@ -852,7 +858,8 @@  int msm_csid_register_entity(struct csid_device *csid,
 	}
 
 	pads[MSM_CSID_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
-	pads[MSM_CSID_PAD_SRC].flags = MEDIA_PAD_FL_SOURCE;
+	for (i = MSM_CSID_PAD_FIRST_SRC; i < MSM_CSID_PADS_NUM; ++i)
+		pads[i].flags = MEDIA_PAD_FL_SOURCE;
 
 	sd->entity.function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
 	sd->entity.ops = &csid_media_ops;
diff --git a/drivers/media/platform/qcom/camss/camss-csid.h b/drivers/media/platform/qcom/camss/camss-csid.h
index f06040e44c51..d4b48432a097 100644
--- a/drivers/media/platform/qcom/camss/camss-csid.h
+++ b/drivers/media/platform/qcom/camss/camss-csid.h
@@ -19,8 +19,13 @@ 
 #include <media/v4l2-subdev.h>
 
 #define MSM_CSID_PAD_SINK 0
-#define MSM_CSID_PAD_SRC 1
-#define MSM_CSID_PADS_NUM 2
+#define MSM_CSID_PAD_FIRST_SRC 1
+#define MSM_CSID_PADS_NUM 5
+
+#define MSM_CSID_PAD_SRC (MSM_CSID_PAD_FIRST_SRC)
+
+/* CSID hardware can demultiplex up to 4 outputs */
+#define MSM_CSID_MAX_SRC_STREAMS	4
 
 #define DATA_TYPE_EMBEDDED_DATA_8BIT	0x12
 #define DATA_TYPE_YUV420_8BIT		0x18
@@ -81,6 +86,8 @@  struct csid_phy_config {
 	u8 csiphy_id;
 	u8 lane_cnt;
 	u32 lane_assign;
+	u32 en_vc;
+	u8 need_vc_update;
 };
 
 struct csid_device;