[PATCH 1/5] drm/dp: Pull drm_dp_link_power_up/down from Tegra to common drm_dp_helper
Andy Yan
andyshrk at 163.com
Fri Mar 14 03:38:40 UTC 2025
From: Andy Yan <andy.yan at rock-chips.com>
The helper functions drm_dp_link_power_up/down were moved to Tegra
DRM at 2019[0].
Now since more and more users are duplicating the same code in their
own drivers, it's time to make them as DRM DP common helpers again.
[0]https://patchwork.freedesktop.org/patch/336850/?series=68031&rev=3
Signed-off-by: Andy Yan <andy.yan at rock-chips.com>
---
drivers/gpu/drm/display/drm_dp_helper.c | 69 +++++++++++++++++++++++++
drivers/gpu/drm/tegra/dp.c | 67 ------------------------
drivers/gpu/drm/tegra/dp.h | 2 -
drivers/gpu/drm/tegra/sor.c | 4 +-
include/drm/display/drm_dp_helper.h | 2 +
5 files changed, 73 insertions(+), 71 deletions(-)
diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c
index dbce1c3f4969..e5dec67e5fca 100644
--- a/drivers/gpu/drm/display/drm_dp_helper.c
+++ b/drivers/gpu/drm/display/drm_dp_helper.c
@@ -838,6 +838,75 @@ int drm_dp_dpcd_read_phy_link_status(struct drm_dp_aux *aux,
}
EXPORT_SYMBOL(drm_dp_dpcd_read_phy_link_status);
+/**
+ * drm_dp_link_power_up() - power up a DisplayPort link
+ * @aux: DisplayPort AUX channel
+ * @revision: DPCD revision supported on the link
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_power_up(struct drm_dp_aux *aux, unsigned char revision)
+{
+ u8 value;
+ int err;
+
+ /* DP_SET_POWER register is only available on DPCD v1.1 and later */
+ if (revision < DP_DPCD_REV_11)
+ return 0;
+
+ err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
+ if (err < 0)
+ return err;
+
+ value &= ~DP_SET_POWER_MASK;
+ value |= DP_SET_POWER_D0;
+
+ err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
+ if (err < 0)
+ return err;
+
+ /*
+ * According to the DP 1.1 specification, a "Sink Device must exit the
+ * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
+ * Control Field" (register 0x600).
+ */
+ usleep_range(1000, 2000);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_power_up);
+
+/**
+ * drm_dp_link_power_down() - power down a DisplayPort link
+ * @aux: DisplayPort AUX channel
+ * @revision: DPCD revision supported on the link
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_link_power_down(struct drm_dp_aux *aux, unsigned char revision)
+{
+ u8 value;
+ int err;
+
+ /* DP_SET_POWER register is only available on DPCD v1.1 and later */
+ if (revision < DP_DPCD_REV_11)
+ return 0;
+
+ err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
+ if (err < 0)
+ return err;
+
+ value &= ~DP_SET_POWER_MASK;
+ value |= DP_SET_POWER_D3;
+
+ err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
+ if (err < 0)
+ return err;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_link_power_down);
+
static int read_payload_update_status(struct drm_dp_aux *aux)
{
int ret;
diff --git a/drivers/gpu/drm/tegra/dp.c b/drivers/gpu/drm/tegra/dp.c
index 08fbd8f151a1..990e744b0923 100644
--- a/drivers/gpu/drm/tegra/dp.c
+++ b/drivers/gpu/drm/tegra/dp.c
@@ -255,73 +255,6 @@ int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
return 0;
}
-/**
- * drm_dp_link_power_up() - power up a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 value;
- int err;
-
- /* DP_SET_POWER register is only available on DPCD v1.1 and later */
- if (link->revision < 0x11)
- return 0;
-
- err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
- if (err < 0)
- return err;
-
- value &= ~DP_SET_POWER_MASK;
- value |= DP_SET_POWER_D0;
-
- err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
- if (err < 0)
- return err;
-
- /*
- * According to the DP 1.1 specification, a "Sink Device must exit the
- * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
- * Control Field" (register 0x600).
- */
- usleep_range(1000, 2000);
-
- return 0;
-}
-
-/**
- * drm_dp_link_power_down() - power down a DisplayPort link
- * @aux: DisplayPort AUX channel
- * @link: pointer to a structure containing the link configuration
- *
- * Returns 0 on success or a negative error code on failure.
- */
-int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
-{
- u8 value;
- int err;
-
- /* DP_SET_POWER register is only available on DPCD v1.1 and later */
- if (link->revision < 0x11)
- return 0;
-
- err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
- if (err < 0)
- return err;
-
- value &= ~DP_SET_POWER_MASK;
- value |= DP_SET_POWER_D3;
-
- err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
- if (err < 0)
- return err;
-
- return 0;
-}
-
/**
* drm_dp_link_configure() - configure a DisplayPort link
* @aux: DisplayPort AUX channel
diff --git a/drivers/gpu/drm/tegra/dp.h b/drivers/gpu/drm/tegra/dp.h
index cb12ed0c54e7..695060cafac0 100644
--- a/drivers/gpu/drm/tegra/dp.h
+++ b/drivers/gpu/drm/tegra/dp.h
@@ -164,8 +164,6 @@ int drm_dp_link_remove_rate(struct drm_dp_link *link, unsigned long rate);
void drm_dp_link_update_rates(struct drm_dp_link *link);
int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
-int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link);
int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
int drm_dp_link_choose(struct drm_dp_link *link,
const struct drm_display_mode *mode,
diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
index f98f70eda906..21f3dfdcc5c9 100644
--- a/drivers/gpu/drm/tegra/sor.c
+++ b/drivers/gpu/drm/tegra/sor.c
@@ -2666,7 +2666,7 @@ static void tegra_sor_dp_disable(struct drm_encoder *encoder)
* the AUX transactions would just be timing out.
*/
if (output->connector.status != connector_status_disconnected) {
- err = drm_dp_link_power_down(sor->aux, &sor->link);
+ err = drm_dp_link_power_down(sor->aux, sor->link.revision);
if (err < 0)
dev_err(sor->dev, "failed to power down link: %d\n",
err);
@@ -2882,7 +2882,7 @@ static void tegra_sor_dp_enable(struct drm_encoder *encoder)
else
dev_dbg(sor->dev, "link training succeeded\n");
- err = drm_dp_link_power_up(sor->aux, &sor->link);
+ err = drm_dp_link_power_up(sor->aux, sor->link.revision);
if (err < 0)
dev_err(sor->dev, "failed to power up DP link: %d\n", err);
diff --git a/include/drm/display/drm_dp_helper.h b/include/drm/display/drm_dp_helper.h
index 5ae4241959f2..f9dabce484a7 100644
--- a/include/drm/display/drm_dp_helper.h
+++ b/include/drm/display/drm_dp_helper.h
@@ -566,6 +566,8 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
int drm_dp_dpcd_read_phy_link_status(struct drm_dp_aux *aux,
enum drm_dp_phy dp_phy,
u8 link_status[DP_LINK_STATUS_SIZE]);
+int drm_dp_link_power_up(struct drm_dp_aux *aux, unsigned char revision);
+int drm_dp_link_power_down(struct drm_dp_aux *aux, unsigned char revision);
int drm_dp_dpcd_write_payload(struct drm_dp_aux *aux,
int vcpid, u8 start_time_slot, u8 time_slot_count);
--
2.34.1
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