[PATCH v2 07/43] drm/bridge: analogix_dp: detect Sink PSR state after configuring the PSR

From: Thierry Escande
Date: Fri Jan 26 2018 - 08:17:49 EST


From: Yakir Yang <ykk@xxxxxxxxxxxxxx>

Make sure the request PSR state takes effect in analogix_dp_send_psr_spd()
function, or print the sink PSR error state if we failed to apply the
requested PSR setting.

Cc: åå ç <wzz@xxxxxxxxxxxxxx>
Cc: StÃphane Marchesin <marcheu@xxxxxxxxxxxx>
Signed-off-by: Yakir Yang <ykk@xxxxxxxxxxxxxx>
[seanpaul changed timeout loop to a readx poll]
Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
Signed-off-by: Thierry Escande <thierry.escande@xxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 6 ++--
drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 6 ++--
drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 35 +++++++++++++++++++---
3 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 1477ea9ba85d..b52de046f5f1 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -122,8 +122,7 @@ int analogix_dp_enable_psr(struct analogix_dp_device *dp)
psr_vsc.DB0 = 0;
psr_vsc.DB1 = EDP_VSC_PSR_STATE_ACTIVE | EDP_VSC_PSR_CRC_VALUES_VALID;

- analogix_dp_send_psr_spd(dp, &psr_vsc);
- return 0;
+ return analogix_dp_send_psr_spd(dp, &psr_vsc);
}
EXPORT_SYMBOL_GPL(analogix_dp_enable_psr);

@@ -149,8 +148,7 @@ int analogix_dp_disable_psr(struct analogix_dp_device *dp)
if (ret != 1)
dev_err(dp->dev, "Failed to set DP Power0 %d\n", ret);

- analogix_dp_send_psr_spd(dp, &psr_vsc);
- return 0;
+ return analogix_dp_send_psr_spd(dp, &psr_vsc);
}
EXPORT_SYMBOL_GPL(analogix_dp_disable_psr);

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
index 5c6a28806129..b039b28d8fcc 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
@@ -20,6 +20,8 @@
#define MAX_CR_LOOP 5
#define MAX_EQ_LOOP 5

+#define DP_TIMEOUT_PSR_LOOP_MS 300
+
/* DP_MAX_LANE_COUNT */
#define DPCD_ENHANCED_FRAME_CAP(x) (((x) >> 7) & 0x1)
#define DPCD_MAX_LANE_COUNT(x) ((x) & 0x1f)
@@ -247,8 +249,8 @@ void analogix_dp_config_video_slave_mode(struct analogix_dp_device *dp);
void analogix_dp_enable_scrambling(struct analogix_dp_device *dp);
void analogix_dp_disable_scrambling(struct analogix_dp_device *dp);
void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp);
-void analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
- struct edp_vsc_psr *vsc);
+int analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
+ struct edp_vsc_psr *vsc);
ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
struct drm_dp_aux_msg *msg);

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
index 303083ad28e3..005a3f7005d2 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
@@ -10,10 +10,11 @@
* option) any later version.
*/

-#include <linux/device.h>
-#include <linux/io.h>
#include <linux/delay.h>
+#include <linux/device.h>
#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>

#include <drm/bridge/analogix_dp.h>

@@ -992,10 +993,25 @@ void analogix_dp_enable_psr_crc(struct analogix_dp_device *dp)
writel(PSR_VID_CRC_ENABLE, dp->reg_base + ANALOGIX_DP_CRC_CON);
}

-void analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
- struct edp_vsc_psr *vsc)
+static ssize_t analogix_dp_get_psr_status(struct analogix_dp_device *dp)
+{
+ ssize_t val;
+ u8 status;
+
+ val = drm_dp_dpcd_readb(&dp->aux, DP_PSR_STATUS, &status);
+ if (val < 0) {
+ dev_err(dp->dev, "PSR_STATUS read failed ret=%zd", val);
+ return val;
+ }
+ return status;
+}
+
+int analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
+ struct edp_vsc_psr *vsc)
{
unsigned int val;
+ int ret;
+ ssize_t psr_status;

/* don't send info frame */
val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
@@ -1036,6 +1052,17 @@ void analogix_dp_send_psr_spd(struct analogix_dp_device *dp,
val = readl(dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
val |= IF_EN;
writel(val, dp->reg_base + ANALOGIX_DP_PKT_SEND_CTL);
+
+ ret = readx_poll_timeout(analogix_dp_get_psr_status, dp, psr_status,
+ psr_status >= 0 &&
+ ((vsc->DB1 && psr_status == DP_PSR_SINK_ACTIVE_RFB) ||
+ (!vsc->DB1 && psr_status == DP_PSR_SINK_INACTIVE)), 1500,
+ DP_TIMEOUT_PSR_LOOP_MS * 1000);
+ if (ret) {
+ dev_warn(dp->dev, "Failed to apply PSR %d\n", ret);
+ return ret;
+ }
+ return 0;
}

ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
--
2.14.1