Re: [PATCH 05/16] media: cadence: csi2rx: Add external DPHY support

Chunfeng Yun
2021-03-31T09:25:17Z

On Tue, 2021-03-30 at 23:03 +0530, Pratyush Yadav wrote:
> Some platforms like TI's J721E can have the CSI2RX paired with an
> external DPHY. Add support to enable and configure the DPHY using the
> generic PHY framework.
>
> Get the pixel rate and bpp from the subdev and pass them on to the DPHY
> along with the number of lanes. All other settings are left to their
> default values.
>
> Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
> ---
> drivers/media/platform/cadence/cdns-csi2rx.c | 147 +++++++++++++++++--
> 1 file changed, 137 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c
> index c68a3eac62cd..31bd80e3f780 100644
> --- a/drivers/media/platform/cadence/cdns-csi2rx.c
> +++ b/drivers/media/platform/cadence/cdns-csi2rx.c
> @@ -30,6 +30,12 @@
> #define CSI2RX_STATIC_CFG_DLANE_MAP(llane, plane) ((plane) << (16 + (llane) * 4))
> #define CSI2RX_STATIC_CFG_LANES_MASK GENMASK(11, 8)
>
> +#define CSI2RX_DPHY_LANE_CTRL_REG 0x40
> +#define CSI2RX_DPHY_CL_RST BIT(16)
> +#define CSI2RX_DPHY_DL_RST(i) BIT((i) + 12)
> +#define CSI2RX_DPHY_CL_EN BIT(4)
> +#define CSI2RX_DPHY_DL_EN(i) BIT(i)
> +
> #define CSI2RX_STREAM_BASE(n) (((n) + 1) * 0x100)
>
> #define CSI2RX_STREAM_CTRL_REG(n) (CSI2RX_STREAM_BASE(n) + 0x000)
> @@ -54,6 +60,11 @@ enum csi2rx_pads {
> CSI2RX_PAD_MAX,
> };
>
> +struct csi2rx_fmt {
> + u32 code;
> + u8 bpp;
> +};
> +
> struct csi2rx_priv {
> struct device *dev;
> unsigned int count;
> @@ -85,6 +96,52 @@ struct csi2rx_priv {
> int source_pad;
> };
>
> +static const struct csi2rx_fmt formats[] = {
> + {
> + .code = MEDIA_BUS_FMT_YUYV8_2X8,
> + .bpp = 16,
> + },
> + {
> + .code = MEDIA_BUS_FMT_UYVY8_2X8,
> + .bpp = 16,
> + },
> + {
> + .code = MEDIA_BUS_FMT_YVYU8_2X8,
> + .bpp = 16,
> + },
> + {
> + .code = MEDIA_BUS_FMT_VYUY8_2X8,
> + .bpp = 16,
> + },
> +};
> +
> +static u8 csi2rx_get_bpp(u32 code)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(formats); i++) {
> + if (formats[i].code == code)
> + return formats[i].bpp;
> + }
> +
> + return 0;
> +}
> +
> +static s64 csi2rx_get_pixel_rate(struct csi2rx_priv *csi2rx)
> +{
> + struct v4l2_ctrl *ctrl;
> +
> + ctrl = v4l2_ctrl_find(csi2rx->source_subdev->ctrl_handler,
> + V4L2_CID_PIXEL_RATE);
> + if (!ctrl) {
> + dev_err(csi2rx->dev, "no pixel rate control in subdev: %s\n",
> + csi2rx->source_subdev->name);
> + return -EINVAL;
> + }
> +
> + return v4l2_ctrl_g_ctrl_int64(ctrl);
> +}
> +
> static inline
> struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev)
> {
> @@ -101,6 +158,55 @@ static void csi2rx_reset(struct csi2rx_priv *csi2rx)
> writel(0, csi2rx->base + CSI2RX_SOFT_RESET_REG);
> }
>
> +static int csi2rx_configure_external_dphy(struct csi2rx_priv *csi2rx)
> +{
> + union phy_configure_opts opts = { };
> + struct phy_configure_opts_mipi_dphy *cfg = &opts.mipi_dphy;
> + struct v4l2_subdev_format sd_fmt;
> + s64 pixel_rate;
> + int ret;
> + u8 bpp;
> +
> + sd_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> + sd_fmt.pad = 0;
> +
> + ret = v4l2_subdev_call(csi2rx->source_subdev, pad, get_fmt, NULL,
> + &sd_fmt);
> + if (ret)
> + return ret;
> +
> + bpp = csi2rx_get_bpp(sd_fmt.format.code);
> + if (!bpp)
> + return -EINVAL;
> +
> + pixel_rate = csi2rx_get_pixel_rate(csi2rx);
> + if (pixel_rate < 0)
> + return pixel_rate;
> +
> + ret = phy_mipi_dphy_get_default_config(pixel_rate, bpp,
> + csi2rx->num_lanes, cfg);
> + if (ret)
> + return ret;
> +
> + ret = phy_set_mode_ext(csi2rx->dphy, PHY_MODE_MIPI_DPHY,
> + PHY_MIPI_DPHY_SUBMODE_RX);
> + if (ret)
> + return ret;
> +
> + ret = phy_power_on(csi2rx->dphy);
> + if (ret)
> + return ret;
Seems phy_power_on, then phy_set_mode_ext?

> +
> + ret = phy_configure(csi2rx->dphy, &opts);
> + if (ret) {
> + /* Can't do anything if it fails. Ignore the return value. */
> + phy_power_off(csi2rx->dphy);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static int csi2rx_start(struct csi2rx_priv *csi2rx)
> {
> unsigned int i;
> @@ -139,6 +245,17 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
> if (ret)
> goto err_disable_pclk;
>
> + /* Enable DPHY clk and data lanes. */
> + if (csi2rx->dphy) {
> + reg = CSI2RX_DPHY_CL_EN | CSI2RX_DPHY_CL_RST;
> + for (i = 0; i < csi2rx->num_lanes; i++) {
> + reg |= CSI2RX_DPHY_DL_EN(csi2rx->lanes[i] - 1);
> + reg |= CSI2RX_DPHY_DL_RST(csi2rx->lanes[i] - 1);
> + }
> +
> + writel(reg, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
> + }
> +
> /*
> * Create a static mapping between the CSI virtual channels
> * and the output stream.
> @@ -169,10 +286,21 @@ static int csi2rx_start(struct csi2rx_priv *csi2rx)
> if (ret)
> goto err_disable_pixclk;
>
> + if (csi2rx->dphy) {
> + ret = csi2rx_configure_external_dphy(csi2rx);
> + if (ret) {
> + dev_err(csi2rx->dev,
> + "Failed to configure external DPHY: %d\n", ret);
> + goto err_disable_sysclk;
> + }
> + }
> +
> clk_disable_unprepare(csi2rx->p_clk);
>
> return 0;
>
> +err_disable_sysclk:
> + clk_disable_unprepare(csi2rx->sys_clk);
> err_disable_pixclk:
> for (; i > 0; i--)
> clk_disable_unprepare(csi2rx->pixel_clk[i - 1]);
> @@ -200,6 +328,13 @@ static void csi2rx_stop(struct csi2rx_priv *csi2rx)
>
> if (v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false))
> dev_warn(csi2rx->dev, "Couldn't disable our subdev\n");
> +
> + if (csi2rx->dphy) {
> + writel(0, csi2rx->base + CSI2RX_DPHY_LANE_CTRL_REG);
> +
> + if (phy_power_off(csi2rx->dphy))
> + dev_warn(csi2rx->dev, "Couldn't power off DPHY\n");
> + }
> }
>
> static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable)
> @@ -306,15 +441,6 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
> return PTR_ERR(csi2rx->dphy);
> }
>
> - /*
> - * FIXME: Once we'll have external D-PHY support, the check
> - * will need to be removed.
> - */
> - if (csi2rx->dphy) {
> - dev_err(&pdev->dev, "External D-PHY not supported yet\n");
> - return -EINVAL;
> - }
> -
> clk_prepare_enable(csi2rx->p_clk);
> dev_cfg = readl(csi2rx->base + CSI2RX_DEVICE_CFG_REG);
> clk_disable_unprepare(csi2rx->p_clk);
> @@ -339,7 +465,7 @@ static int csi2rx_get_resources(struct csi2rx_priv *csi2rx,
> * FIXME: Once we'll have internal D-PHY support, the check
> * will need to be removed.
> */
> - if (csi2rx->has_internal_dphy) {
> + if (!csi2rx->dphy && csi2rx->has_internal_dphy) {
> dev_err(&pdev->dev, "Internal D-PHY not supported yet\n");
> return -EINVAL;
> }
> @@ -460,6 +586,7 @@ static int csi2rx_probe(struct platform_device *pdev)
> dev_info(&pdev->dev,
> "Probed CSI2RX with %u/%u lanes, %u streams, %s D-PHY\n",
> csi2rx->num_lanes, csi2rx->max_lanes, csi2rx->max_streams,
> + csi2rx->dphy ? "external" :
> csi2rx->has_internal_dphy ? "internal" : "no");
>
> return 0;