Re: [PATCH v1 06/10] drm/bridge: analogix_dp: Add support for phy configuration.

Dmitry Baryshkov
2024-11-30T08:54:09Z

On Wed, Nov 27, 2024 at 03:51:53PM +0800, Damon Ding wrote:
> Add support to configurate link rate, lane count, voltage swing and
> pre-emphasis with phy_configure(). It is helpful in application scenarios
> where analogix controller is mixed with the phy of other vendors.
>
> Signed-off-by: Damon Ding <damon.ding@rock-chips.com>
> ---
> .../drm/bridge/analogix/analogix_dp_core.c | 4 +-
> .../drm/bridge/analogix/analogix_dp_core.h | 2 +
> .../gpu/drm/bridge/analogix/analogix_dp_reg.c | 90 +++++++++++++++++++
> 3 files changed, 94 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 6f10d88a34c5..7624ed13cdbf 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -1672,7 +1672,7 @@ EXPORT_SYMBOL_GPL(analogix_dp_probe);
>
> int analogix_dp_suspend(struct analogix_dp_device *dp)
> {
> - phy_power_off(dp->phy);
> + analogix_dp_phy_power_off(dp);

Why?

>
> if (dp->plat_data->power_off)
> dp->plat_data->power_off(dp->plat_data);
> @@ -1696,7 +1696,7 @@ int analogix_dp_resume(struct analogix_dp_device *dp)
> if (dp->plat_data->power_on)
> dp->plat_data->power_on(dp->plat_data);
>
> - phy_power_on(dp->phy);
> + analogix_dp_phy_power_on(dp);

Why?

>
> analogix_dp_init_dp(dp);
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> index 774d11574b09..a76079d61768 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> @@ -232,5 +232,7 @@ int analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
> struct dp_sdp *vsc, bool blocking);
> ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
> struct drm_dp_aux_msg *msg);
> +void analogix_dp_phy_power_on(struct analogix_dp_device *dp);
> +void analogix_dp_phy_power_off(struct analogix_dp_device *dp);
>
> #endif /* _ANALOGIX_DP_CORE_H */
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> index 3afc73c858c4..809bb0c72d18 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> @@ -11,6 +11,7 @@
> #include <linux/gpio/consumer.h>
> #include <linux/io.h>
> #include <linux/iopoll.h>
> +#include <linux/phy/phy.h>
>
> #include <drm/bridge/analogix_dp.h>
>
> @@ -513,10 +514,27 @@ void analogix_dp_enable_sw_function(struct analogix_dp_device *dp)
> void analogix_dp_set_link_bandwidth(struct analogix_dp_device *dp, u32 bwtype)
> {
> u32 reg;
> + int ret;
>
> reg = bwtype;
> if ((bwtype == DP_LINK_BW_2_7) || (bwtype == DP_LINK_BW_1_62))
> writel(reg, dp->reg_base + ANALOGIX_DP_LINK_BW_SET);
> +
> + if (dp->phy) {
> + union phy_configure_opts phy_cfg = {0};
> +
> + phy_cfg.dp.lanes = dp->link_train.lane_count;

You can drop this, .set_lanes is false.

> + phy_cfg.dp.link_rate =
> + drm_dp_bw_code_to_link_rate(dp->link_train.link_rate) / 100;
> + phy_cfg.dp.set_lanes = false;
> + phy_cfg.dp.set_rate = true;
> + phy_cfg.dp.set_voltages = false;

You don't need to set those to false, it's cleared by = {0};

> + ret = phy_configure(dp->phy, &phy_cfg);
> + if (ret && ret != -EOPNOTSUPP) {
> + dev_err(dp->dev, "%s: phy_configure() failed: %d\n", __func__, ret);
> + return;
> + }
> + }
> }
>
> void analogix_dp_get_link_bandwidth(struct analogix_dp_device *dp, u32 *bwtype)
> @@ -530,9 +548,24 @@ void analogix_dp_get_link_bandwidth(struct analogix_dp_device *dp, u32 *bwtype)
> void analogix_dp_set_lane_count(struct analogix_dp_device *dp, u32 count)
> {
> u32 reg;
> + int ret;
>
> reg = count;
> writel(reg, dp->reg_base + ANALOGIX_DP_LANE_COUNT_SET);
> +
> + if (dp->phy) {
> + union phy_configure_opts phy_cfg = {0};
> +
> + phy_cfg.dp.lanes = dp->link_train.lane_count;
> + phy_cfg.dp.set_lanes = true;
> + phy_cfg.dp.set_rate = false;
> + phy_cfg.dp.set_voltages = false;

Likewise

> + ret = phy_configure(dp->phy, &phy_cfg);
> + if (ret && ret != -EOPNOTSUPP) {
> + dev_err(dp->dev, "%s: phy_configure() failed: %d\n", __func__, ret);
> + return;
> + }
> + }
> }
>
> void analogix_dp_get_lane_count(struct analogix_dp_device *dp, u32 *count)
> @@ -546,10 +579,39 @@ void analogix_dp_get_lane_count(struct analogix_dp_device *dp, u32 *count)
> void analogix_dp_set_lane_link_training(struct analogix_dp_device *dp)
> {
> u8 lane;
> + int ret;
>
> for (lane = 0; lane < dp->link_train.lane_count; lane++)
> writel(dp->link_train.training_lane[lane],
> dp->reg_base + ANALOGIX_DP_LN0_LINK_TRAINING_CTL + 4 * lane);
> +
> + if (dp->phy) {
> + union phy_configure_opts phy_cfg = {0};
> +
> + for (lane = 0; lane < dp->link_train.lane_count; lane++) {
> + u8 training_lane = dp->link_train.training_lane[lane];
> + u8 vs, pe;
> +
> + vs = (training_lane & DP_TRAIN_VOLTAGE_SWING_MASK) >>
> + DP_TRAIN_VOLTAGE_SWING_SHIFT;
> + pe = (training_lane & DP_TRAIN_PRE_EMPHASIS_MASK) >>
> + DP_TRAIN_PRE_EMPHASIS_SHIFT;
> + phy_cfg.dp.voltage[lane] = vs;
> + phy_cfg.dp.pre[lane] = pe;
> + }
> +
> + phy_cfg.dp.lanes = dp->link_train.lane_count;
> + phy_cfg.dp.link_rate =
> + drm_dp_bw_code_to_link_rate(dp->link_train.link_rate) / 100;

You can drop these two.

> + phy_cfg.dp.set_lanes = false;
> + phy_cfg.dp.set_rate = false;
> + phy_cfg.dp.set_voltages = true;
> + ret = phy_configure(dp->phy, &phy_cfg);
> + if (ret && ret != -EOPNOTSUPP) {
> + dev_err(dp->dev, "%s: phy_configure() failed: %d\n", __func__, ret);
> + return;
> + }
> + }
> }
>
> u32 analogix_dp_get_lane_link_training(struct analogix_dp_device *dp, u8 lane)
> @@ -1053,3 +1115,31 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
>
> return -EREMOTEIO;
> }
> +
> +void analogix_dp_phy_power_on(struct analogix_dp_device *dp)
> +{
> + int ret;
> +
> + ret = phy_set_mode(dp->phy, PHY_MODE_DP);
> + if (ret) {
> + dev_err(dp->dev, "%s: phy_set_mode() failed: %d\n", __func__, ret);
> + return;
> + }
> +
> + ret = phy_power_on(dp->phy);
> + if (ret) {
> + dev_err(dp->dev, "%s: phy_power_on() failed: %d\n", __func__, ret);

There is already a dev_err() call in phy_power_on().

> + return;
> + }
> +}
> +
> +void analogix_dp_phy_power_off(struct analogix_dp_device *dp)
> +{
> + int ret;
> +
> + ret = phy_power_off(dp->phy);
> + if (ret) {
> + dev_err(dp->dev, "%s: phy_power_off() failed: %d\n", __func__, ret);

There is already a dev_err() call in phy_power_off().

> + return;
> + }
> +}
> --
> 2.34.1
>
>
> _______________________________________________
> Linux-rockchip mailing list
> Linux-rockchip@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-rockchip

--
With best wishes
Dmitry