Re: [PATCH] drm/msm/dsi: Parse lane swap information from DT

Hi,

On 9/4/2015 12:00 AM, Hai Li wrote:

Lane swap configuration is based on the board design. This change allows the DSI host to get this information from device tree, instead of hardcoding in driver.

Signed-off-by: Hai Li hali@codeaurora.org

Documentation/devicetree/bindings/drm/msm/dsi.txt | 13 ++++++ drivers/gpu/drm/msm/dsi/dsi_host.c | 49 +++++++++++++++++------ 2 files changed, 49 insertions(+), 13 deletions(-)

diff --git a/Documentation/devicetree/bindings/drm/msm/dsi.txt b/Documentation/devicetree/bindings/drm/msm/dsi.txt index d56923c..febcc51 100644 --- a/Documentation/devicetree/bindings/drm/msm/dsi.txt +++ b/Documentation/devicetree/bindings/drm/msm/dsi.txt @@ -44,6 +44,17 @@ Optional properties:

• port: DSI controller output port. This contains one endpoint subnode, with its remote-endpoint set to the phandle of the connected panel's endpoint. See Documentation/devicetree/bindings/graph.txt for device graph info.

+- qcom,dsi-logical-lane-swap: Character string to swap logical lane to physical

• lane mapping. Supported lane mappings:

• "0123": Logic 0->Phys 0; Logic 1->Phys 1; Logic 2->Phys 2; Logic 3->Phys 3;

• "3012": Logic 3->Phys 0; Logic 0->Phys 1; Logic 1->Phys 2; Logic 2->Phys 3;

• "2301": Logic 2->Phys 0; Logic 3->Phys 1; Logic 0->Phys 2; Logic 1->Phys 3;

• "1230": Logic 1->Phys 0; Logic 2->Phys 1; Logic 3->Phys 2; Logic 0->Phys 3;

• "0321": Logic 0->Phys 0; Logic 3->Phys 1; Logic 2->Phys 2; Logic 1->Phys 3;

• "1032": Logic 1->Phys 0; Logic 0->Phys 1; Logic 3->Phys 2; Logic 2->Phys 3;

• "2103": Logic 2->Phys 0; Logic 1->Phys 1; Logic 0->Phys 2; Logic 3->Phys 3;

• "3210": Logic 3->Phys 0; Logic 2->Phys 1; Logic 1->Phys 2; Logic 0->Phys 3;

• Default value is "0123", which means no lane swap.

  DSI PHY: Required properties:

@@ -129,6 +140,8 @@ Example: remote-endpoint = <&panel_in>; }; };

• qcom,dsi-logical-lane-swap = "0123";
  

  };

I think we could keep this in the output port DT node instead, since it is more of a property of how it connects to the panel.

There is a more generic way to represent lane info. It would be nice to have a look at what's done here:

http://marc.info/?l=linux-omap&m=133605367610068&w=2

and it's usage here:

http://lxr.free-electrons.com/source/arch/arm/boot/dts/omap4-sdp.dts#L647

Thanks, Archit

mdss_dsi_phy0: qcom,mdss_dsi_phy@fd922a00 { diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index 8d82973f..eaba417 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -131,6 +131,7 @@ struct msm_dsi_host { enum mipi_dsi_pixel_format format; unsigned long mode_flags;

• u32 dlane_swap; u32 dma_cmd_ctrl_restore;

  bool registered;

@@ -684,19 +685,9 @@ static void dsi_ctrl_config(struct msm_dsi_host *msm_host, bool enable, data = DSI_CTRL_CLK_EN;

DBG("lane number=%d", msm_host->lanes);

• if (msm_host->lanes == 2) {

• data |= DSI_CTRL_LANE1 | DSI_CTRL_LANE2;
  

• /* swap lanes for 2-lane panel for better performance */
  

• dsi_write(msm_host, REG_DSI_LANE_SWAP_CTRL,
  

• 	DSI_LANE_SWAP_CTRL_DLN_SWAP_SEL(LANE_SWAP_1230));
  

• } else {

• /* Take 4 lanes as default */
  

• data |= DSI_CTRL_LANE0 | DSI_CTRL_LANE1 | DSI_CTRL_LANE2 |
  

• 	DSI_CTRL_LANE3;
  

• /* Do not swap lanes for 4-lane panel */
  

• dsi_write(msm_host, REG_DSI_LANE_SWAP_CTRL,
  

• 	DSI_LANE_SWAP_CTRL_DLN_SWAP_SEL(LANE_SWAP_0123));
  

• }

• data |= ((DSI_CTRL_LANE0 << msm_host->lanes) - DSI_CTRL_LANE0);

• dsi_write(msm_host, REG_DSI_LANE_SWAP_CTRL,

• DSI_LANE_SWAP_CTRL_DLN_SWAP_SEL(msm_host->dlane_swap));
  
  

  if (!(flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)) dsi_write(msm_host, REG_DSI_LANE_CTRL,

@@ -1289,6 +1280,9 @@ static int dsi_host_attach(struct mipi_dsi_host *host, struct msm_dsi_host *msm_host = to_msm_dsi_host(host); int ret;

• if (dsi->lanes > 4 || dsi->channel > 3)

• return -EINVAL;
  

• msm_host->channel = dsi->channel; msm_host->lanes = dsi->lanes; msm_host->format = dsi->format;

@@ -1344,6 +1338,33 @@ static struct mipi_dsi_host_ops dsi_host_ops = { .transfer = dsi_host_transfer, };

+static void dsi_parse_dlane_swap(struct msm_dsi_host *msm_host,

• 		struct device_node *np)
  

+{

• const char *lane_swap;
• lane_swap = of_get_property(np, "qcom,dsi-logical-lane-swap", NULL);
• if (!lane_swap)

• msm_host->dlane_swap = LANE_SWAP_0123;
  

• else if (!strncmp(lane_swap, "3012", 5))

• msm_host->dlane_swap = LANE_SWAP_3012;
  

• else if (!strncmp(lane_swap, "2301", 5))

• msm_host->dlane_swap = LANE_SWAP_2301;
  

• else if (!strncmp(lane_swap, "1230", 5))

• msm_host->dlane_swap = LANE_SWAP_1230;
  

• else if (!strncmp(lane_swap, "0321", 5))

• msm_host->dlane_swap = LANE_SWAP_0321;
  

• else if (!strncmp(lane_swap, "1032", 5))

• msm_host->dlane_swap = LANE_SWAP_1032;
  

• else if (!strncmp(lane_swap, "2103", 5))

• msm_host->dlane_swap = LANE_SWAP_2103;
  

• else if (!strncmp(lane_swap, "3210", 5))

• msm_host->dlane_swap = LANE_SWAP_3210;
  

• else

• msm_host->dlane_swap = LANE_SWAP_0123;
  

+}

• static int dsi_host_parse_dt(struct msm_dsi_host *msm_host) { struct device *dev = &msm_host->pdev->dev;

@@ -1358,6 +1379,8 @@ static int dsi_host_parse_dt(struct msm_dsi_host *msm_host) return ret; }

• dsi_parse_dlane_swap(msm_host, np);
• /*
  • Get the first endpoint node. In our case, dsi has one output port
  • to which the panel is connected. Don't return an error if a port