From: Thierry Reding <tred...@nvidia.com>
The new drm_dp_dpcd_dump() helper dumps the contents of a DPCD to a
seq_file and can be used to make the DPCD available via debugfs for
example.
Signed-off-by: Thierry Reding <treding at nvidia.com>
---
drivers/gpu/drm/drm_dp_helper.c | 146 ++++++++++++++++++++++++++++++++++++++++
include/drm/drm_dp_helper.h | 2 +
2 files changed, 148 insertions(+)
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 8968201ea93c..ea74884c9cb3 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -27,6 +27,7 @@
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/i2c.h>
+#include <linux/seq_file.h>
#include <drm/drm_dp_helper.h>
#include <drm/drmP.h>
@@ -292,6 +293,151 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
}
EXPORT_SYMBOL(drm_dp_dpcd_read_link_status);
+/**
+ * drm_dp_dpcd_dump() - dump DPCD content
+ * @aux: DisplayPort AUX channel
+ * @s: destination for DPCD dump
+ *
+ * Reads registers from the DPCD via a DisplayPort AUX channel and dumps them
+ * to a seq_file.
+ */
+void drm_dp_dpcd_dump(struct drm_dp_aux *aux, struct seq_file *s)
+{
+#define DUMP_REG(aux, offset) ({ \
+ u8 value; \
+ int err; \
+ err = drm_dp_dpcd_readb(aux, offset, &value); \
+ if (err < 0) { \
+ dev_err((aux)->dev, "failed to read %s: %d\n", \
+ #offset, err); \
+ return; \
+ } \
+ seq_printf(s, "%-35s 0x%04x 0x%02x\n", #offset, offset, \
+ value); \
+ })
+
+ DUMP_REG(aux, DP_DPCD_REV);
+ DUMP_REG(aux, DP_MAX_LINK_RATE);
+ DUMP_REG(aux, DP_MAX_LANE_COUNT);
+ DUMP_REG(aux, DP_MAX_DOWNSPREAD);
+ DUMP_REG(aux, DP_NORP);
+ DUMP_REG(aux, DP_DOWNSTREAMPORT_PRESENT);
+ DUMP_REG(aux, DP_MAIN_LINK_CHANNEL_CODING);
+ DUMP_REG(aux, DP_DOWN_STREAM_PORT_COUNT);
+ DUMP_REG(aux, DP_RECEIVE_PORT_0_CAP_0);
+ DUMP_REG(aux, DP_RECEIVE_PORT_0_BUFFER_SIZE);
+ DUMP_REG(aux, DP_RECEIVE_PORT_1_CAP_0);
+ DUMP_REG(aux, DP_RECEIVE_PORT_1_BUFFER_SIZE);
+ DUMP_REG(aux, DP_I2C_SPEED_CAP);
+ DUMP_REG(aux, DP_EDP_CONFIGURATION_CAP);
+ DUMP_REG(aux, DP_TRAINING_AUX_RD_INTERVAL);
+ DUMP_REG(aux, DP_ADAPTER_CAP);
+ DUMP_REG(aux, DP_SUPPORTED_LINK_RATES);
+ DUMP_REG(aux, DP_FAUX_CAP);
+ DUMP_REG(aux, DP_MSTM_CAP);
+ DUMP_REG(aux, DP_NUMBER_OF_AUDIO_ENDPOINTS);
+ DUMP_REG(aux, DP_AV_GRANULARITY);
+ DUMP_REG(aux, DP_AUD_DEC_LAT0);
+ DUMP_REG(aux, DP_AUD_DEC_LAT1);
+ DUMP_REG(aux, DP_AUD_PP_LAT0);
+ DUMP_REG(aux, DP_AUD_PP_LAT1);
+ DUMP_REG(aux, DP_VID_INTER_LAT);
+ DUMP_REG(aux, DP_VID_PROG_LAT);
+ DUMP_REG(aux, DP_REP_LAT);
+ DUMP_REG(aux, DP_AUD_DEL_INS0);
+ DUMP_REG(aux, DP_AUD_DEL_INS1);
+ DUMP_REG(aux, DP_AUD_DEL_INS2);
+ DUMP_REG(aux, DP_RECEIVER_ALPM_CAP);
+ DUMP_REG(aux, DP_AUD_DEL_INS0);
+ DUMP_REG(aux, DP_GUID);
+ DUMP_REG(aux, DP_PSR_SUPPORT);
+ DUMP_REG(aux, DP_PSR_CAPS);
+ DUMP_REG(aux, DP_DOWNSTREAM_PORT_0);
+ DUMP_REG(aux, DP_LINK_BW_SET);
+ DUMP_REG(aux, DP_LANE_COUNT_SET);
+ DUMP_REG(aux, DP_TRAINING_PATTERN_SET);
+ DUMP_REG(aux, DP_TRAINING_LANE0_SET);
+ DUMP_REG(aux, DP_TRAINING_LANE1_SET);
+ DUMP_REG(aux, DP_TRAINING_LANE2_SET);
+ DUMP_REG(aux, DP_TRAINING_LANE3_SET);
+ DUMP_REG(aux, DP_DOWNSPREAD_CTRL);
+ DUMP_REG(aux, DP_MAIN_LINK_CHANNEL_CODING_SET);
+ DUMP_REG(aux, DP_I2C_SPEED_CONTROL_STATUS);
+ DUMP_REG(aux, DP_EDP_CONFIGURATION_SET);
+ DUMP_REG(aux, DP_LINK_QUAL_LANE0_SET);
+ DUMP_REG(aux, DP_LINK_QUAL_LANE1_SET);
+ DUMP_REG(aux, DP_LINK_QUAL_LANE2_SET);
+ DUMP_REG(aux, DP_LINK_QUAL_LANE3_SET);
+ DUMP_REG(aux, DP_TRAINING_LANE0_1_SET2);
+ DUMP_REG(aux, DP_TRAINING_LANE2_3_SET2);
+ DUMP_REG(aux, DP_MSTM_CTRL);
+ DUMP_REG(aux, DP_AUDIO_DELAY0);
+ DUMP_REG(aux, DP_AUDIO_DELAY1);
+ DUMP_REG(aux, DP_AUDIO_DELAY2);
+ DUMP_REG(aux, DP_LINK_RATE_SET);
+ DUMP_REG(aux, DP_RECEIVER_ALPM_CONFIG);
+ DUMP_REG(aux, DP_SINK_DEVICE_AUX_FRAME_SYNC_CONF);
+ DUMP_REG(aux, DP_UPSTREAM_DEVICE_DP_PWR_NEED);
+ DUMP_REG(aux, DP_AUX_FRAME_SYNC_VALUE);
+ DUMP_REG(aux, DP_PSR_EN_CFG);
+ DUMP_REG(aux, DP_ADAPTER_CTRL);
+ DUMP_REG(aux, DP_BRANCH_DEVICE_CTRL);
+ DUMP_REG(aux, DP_PAYLOAD_ALLOCATE_SET);
+ DUMP_REG(aux, DP_PAYLOAD_ALLOCATE_START_TIME_SLOT);
+ DUMP_REG(aux, DP_PAYLOAD_ALLOCATE_TIME_SLOT_COUNT);
+ DUMP_REG(aux, DP_SINK_COUNT);
+ DUMP_REG(aux, DP_DEVICE_SERVICE_IRQ_VECTOR);
+ DUMP_REG(aux, DP_LANE0_1_STATUS);
+ DUMP_REG(aux, DP_LANE2_3_STATUS);
+ DUMP_REG(aux, DP_LANE_ALIGN_STATUS_UPDATED);
+ DUMP_REG(aux, DP_SINK_STATUS);
+ DUMP_REG(aux, DP_ADJUST_REQUEST_LANE0_1);
+ DUMP_REG(aux, DP_ADJUST_REQUEST_LANE2_3);
+ DUMP_REG(aux, DP_TEST_REQUEST);
+ DUMP_REG(aux, DP_TEST_LINK_RATE);
+ DUMP_REG(aux, DP_TEST_LANE_COUNT);
+ DUMP_REG(aux, DP_TEST_CRC_R_CR);
+ DUMP_REG(aux, DP_TEST_CRC_G_Y);
+ DUMP_REG(aux, DP_TEST_CRC_B_CB);
+ DUMP_REG(aux, DP_TEST_SINK_MISC);
+ DUMP_REG(aux, DP_TEST_RESPONSE);
+ DUMP_REG(aux, DP_TEST_EDID_CHECKSUM);
+ DUMP_REG(aux, DP_TEST_SINK);
+ DUMP_REG(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS);
+ DUMP_REG(aux, DP_VC_PAYLOAD_ID_SLOT_1);
+ DUMP_REG(aux, DP_SOURCE_OUI);
+ DUMP_REG(aux, DP_SINK_OUI);
+ DUMP_REG(aux, DP_BRANCH_OUI);
+ DUMP_REG(aux, DP_SET_POWER);
+ DUMP_REG(aux, DP_EDP_DPCD_REV);
+ DUMP_REG(aux, DP_EDP_GENERAL_CAP_1);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_ADJUSTMENT_CAP);
+ DUMP_REG(aux, DP_EDP_GENERAL_CAP_2);
+ DUMP_REG(aux, DP_EDP_GENERAL_CAP_3);
+ DUMP_REG(aux, DP_EDP_DISPLAY_CONTROL_REGISTER);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_MODE_SET_REGISTER);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_MSB);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_BRIGHTNESS_LSB);
+ DUMP_REG(aux, DP_EDP_PWMGEN_BIT_COUNT);
+ DUMP_REG(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MIN);
+ DUMP_REG(aux, DP_EDP_PWMGEN_BIT_COUNT_CAP_MAX);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_CONTROL_STATUS);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_SET);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MIN_MSB);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MIN_MID);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MIN_LSB);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MAX_MSB);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MAX_MID);
+ DUMP_REG(aux, DP_EDP_BACKLIGHT_FREQ_CAP_MAX_LSB);
+ DUMP_REG(aux, DP_EDP_DBC_MINIMUM_BRIGHTNESS_SET);
+ DUMP_REG(aux, DP_EDP_DBC_MAXIMUM_BRIGHTNESS_SET);
+ DUMP_REG(aux, DP_EDP_REGIONAL_BACKLIGHT_BASE);
+ DUMP_REG(aux, DP_EDP_REGIONAL_BACKLIGHT_0);
+
+#undef DUMP_REG
+}
+EXPORT_SYMBOL(drm_dp_dpcd_dump);
+
static void drm_dp_link_reset(struct drm_dp_link *link)
{
if (!link)
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index d041bb00d6a0..089d274f857d 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -754,6 +754,8 @@ static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux
*aux,
int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
u8 status[DP_LINK_STATUS_SIZE]);
+void drm_dp_dpcd_dump(struct drm_dp_aux *aux, struct seq_file *s);
+
/**
* struct drm_dp_link_train_set - link training settings
* @voltage_swing: per-lane voltage swing
--
2.4.5
