diff options
Diffstat (limited to 'include/drm/drm_dp_helper.h')
| -rw-r--r-- | include/drm/drm_dp_helper.h | 467 |
1 files changed, 448 insertions, 19 deletions
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 83a389e4454..a21568bf151 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -25,25 +25,39 @@ #include <linux/types.h> #include <linux/i2c.h> +#include <linux/delay.h> -/* From the VESA DisplayPort spec */ +/* + * Unless otherwise noted, all values are from the DP 1.1a spec. Note that + * DP and DPCD versions are independent. Differences from 1.0 are not noted, + * 1.0 devices basically don't exist in the wild. + * + * Abbreviations, in chronological order: + * + * eDP: Embedded DisplayPort version 1 + * DPI: DisplayPort Interoperability Guideline v1.1a + * 1.2: DisplayPort 1.2 + * MST: Multistream Transport - part of DP 1.2a + * + * 1.2 formally includes both eDP and DPI definitions. + */ -#define AUX_NATIVE_WRITE 0x8 -#define AUX_NATIVE_READ 0x9 -#define AUX_I2C_WRITE 0x0 -#define AUX_I2C_READ 0x1 -#define AUX_I2C_STATUS 0x2 -#define AUX_I2C_MOT 0x4 +#define DP_AUX_I2C_WRITE 0x0 +#define DP_AUX_I2C_READ 0x1 +#define DP_AUX_I2C_STATUS 0x2 +#define DP_AUX_I2C_MOT 0x4 +#define DP_AUX_NATIVE_WRITE 0x8 +#define DP_AUX_NATIVE_READ 0x9 -#define AUX_NATIVE_REPLY_ACK (0x0 << 4) -#define AUX_NATIVE_REPLY_NACK (0x1 << 4) -#define AUX_NATIVE_REPLY_DEFER (0x2 << 4) -#define AUX_NATIVE_REPLY_MASK (0x3 << 4) +#define DP_AUX_NATIVE_REPLY_ACK (0x0 << 0) +#define DP_AUX_NATIVE_REPLY_NACK (0x1 << 0) +#define DP_AUX_NATIVE_REPLY_DEFER (0x2 << 0) +#define DP_AUX_NATIVE_REPLY_MASK (0x3 << 0) -#define AUX_I2C_REPLY_ACK (0x0 << 6) -#define AUX_I2C_REPLY_NACK (0x1 << 6) -#define AUX_I2C_REPLY_DEFER (0x2 << 6) -#define AUX_I2C_REPLY_MASK (0x3 << 6) +#define DP_AUX_I2C_REPLY_ACK (0x0 << 2) +#define DP_AUX_I2C_REPLY_NACK (0x1 << 2) +#define DP_AUX_I2C_REPLY_DEFER (0x2 << 2) +#define DP_AUX_I2C_REPLY_MASK (0x3 << 2) /* AUX CH addresses */ /* DPCD */ @@ -53,6 +67,7 @@ #define DP_MAX_LANE_COUNT 0x002 # define DP_MAX_LANE_COUNT_MASK 0x1f +# define DP_TPS3_SUPPORTED (1 << 6) /* 1.2 */ # define DP_ENHANCED_FRAME_CAP (1 << 7) #define DP_MAX_DOWNSPREAD 0x003 @@ -63,18 +78,84 @@ #define DP_DOWNSTREAMPORT_PRESENT 0x005 # define DP_DWN_STRM_PORT_PRESENT (1 << 0) # define DP_DWN_STRM_PORT_TYPE_MASK 0x06 -/* 00b = DisplayPort */ -/* 01b = Analog */ -/* 10b = TMDS or HDMI */ -/* 11b = Other */ +# define DP_DWN_STRM_PORT_TYPE_DP (0 << 1) +# define DP_DWN_STRM_PORT_TYPE_ANALOG (1 << 1) +# define DP_DWN_STRM_PORT_TYPE_TMDS (2 << 1) +# define DP_DWN_STRM_PORT_TYPE_OTHER (3 << 1) # define DP_FORMAT_CONVERSION (1 << 3) +# define DP_DETAILED_CAP_INFO_AVAILABLE (1 << 4) /* DPI */ #define DP_MAIN_LINK_CHANNEL_CODING 0x006 +#define DP_DOWN_STREAM_PORT_COUNT 0x007 +# define DP_PORT_COUNT_MASK 0x0f +# define DP_MSA_TIMING_PAR_IGNORED (1 << 6) /* eDP */ +# define DP_OUI_SUPPORT (1 << 7) + +#define DP_I2C_SPEED_CAP 0x00c /* DPI */ +# define DP_I2C_SPEED_1K 0x01 +# define DP_I2C_SPEED_5K 0x02 +# define DP_I2C_SPEED_10K 0x04 +# define DP_I2C_SPEED_100K 0x08 +# define DP_I2C_SPEED_400K 0x10 +# define DP_I2C_SPEED_1M 0x20 + +#define DP_EDP_CONFIGURATION_CAP 0x00d /* XXX 1.2? */ +#define DP_TRAINING_AUX_RD_INTERVAL 0x00e /* XXX 1.2? */ + +/* Multiple stream transport */ +#define DP_FAUX_CAP 0x020 /* 1.2 */ +# define DP_FAUX_CAP_1 (1 << 0) + +#define DP_MSTM_CAP 0x021 /* 1.2 */ +# define DP_MST_CAP (1 << 0) + +#define DP_GUID 0x030 /* 1.2 */ + +#define DP_PSR_SUPPORT 0x070 /* XXX 1.2? */ +# define DP_PSR_IS_SUPPORTED 1 +#define DP_PSR_CAPS 0x071 /* XXX 1.2? */ +# define DP_PSR_NO_TRAIN_ON_EXIT 1 +# define DP_PSR_SETUP_TIME_330 (0 << 1) +# define DP_PSR_SETUP_TIME_275 (1 << 1) +# define DP_PSR_SETUP_TIME_220 (2 << 1) +# define DP_PSR_SETUP_TIME_165 (3 << 1) +# define DP_PSR_SETUP_TIME_110 (4 << 1) +# define DP_PSR_SETUP_TIME_55 (5 << 1) +# define DP_PSR_SETUP_TIME_0 (6 << 1) +# define DP_PSR_SETUP_TIME_MASK (7 << 1) +# define DP_PSR_SETUP_TIME_SHIFT 1 + +/* + * 0x80-0x8f describe downstream port capabilities, but there are two layouts + * based on whether DP_DETAILED_CAP_INFO_AVAILABLE was set. If it was not, + * each port's descriptor is one byte wide. If it was set, each port's is + * four bytes wide, starting with the one byte from the base info. As of + * DP interop v1.1a only VGA defines additional detail. + */ + +/* offset 0 */ +#define DP_DOWNSTREAM_PORT_0 0x80 +# define DP_DS_PORT_TYPE_MASK (7 << 0) +# define DP_DS_PORT_TYPE_DP 0 +# define DP_DS_PORT_TYPE_VGA 1 +# define DP_DS_PORT_TYPE_DVI 2 +# define DP_DS_PORT_TYPE_HDMI 3 +# define DP_DS_PORT_TYPE_NON_EDID 4 +# define DP_DS_PORT_HPD (1 << 3) +/* offset 1 for VGA is maximum megapixels per second / 8 */ +/* offset 2 */ +# define DP_DS_VGA_MAX_BPC_MASK (3 << 0) +# define DP_DS_VGA_8BPC 0 +# define DP_DS_VGA_10BPC 1 +# define DP_DS_VGA_12BPC 2 +# define DP_DS_VGA_16BPC 3 + /* link configuration */ #define DP_LINK_BW_SET 0x100 # define DP_LINK_BW_1_62 0x06 # define DP_LINK_BW_2_7 0x0a +# define DP_LINK_BW_5_4 0x14 /* 1.2 */ #define DP_LANE_COUNT_SET 0x101 # define DP_LANE_COUNT_MASK 0x0f @@ -84,6 +165,7 @@ # define DP_TRAINING_PATTERN_DISABLE 0 # define DP_TRAINING_PATTERN_1 1 # define DP_TRAINING_PATTERN_2 2 +# define DP_TRAINING_PATTERN_3 3 /* 1.2 */ # define DP_TRAINING_PATTERN_MASK 0x3 # define DP_LINK_QUAL_PATTERN_DISABLE (0 << 2) @@ -124,10 +206,51 @@ #define DP_DOWNSPREAD_CTRL 0x107 # define DP_SPREAD_AMP_0_5 (1 << 4) +# define DP_MSA_TIMING_PAR_IGNORE_EN (1 << 7) /* eDP */ #define DP_MAIN_LINK_CHANNEL_CODING_SET 0x108 # define DP_SET_ANSI_8B10B (1 << 0) +#define DP_I2C_SPEED_CONTROL_STATUS 0x109 /* DPI */ +/* bitmask as for DP_I2C_SPEED_CAP */ + +#define DP_EDP_CONFIGURATION_SET 0x10a /* XXX 1.2? */ + +#define DP_MSTM_CTRL 0x111 /* 1.2 */ +# define DP_MST_EN (1 << 0) +# define DP_UP_REQ_EN (1 << 1) +# define DP_UPSTREAM_IS_SRC (1 << 2) + +#define DP_PSR_EN_CFG 0x170 /* XXX 1.2? */ +# define DP_PSR_ENABLE (1 << 0) +# define DP_PSR_MAIN_LINK_ACTIVE (1 << 1) +# define DP_PSR_CRC_VERIFICATION (1 << 2) +# define DP_PSR_FRAME_CAPTURE (1 << 3) + +#define DP_ADAPTER_CTRL 0x1a0 +# define DP_ADAPTER_CTRL_FORCE_LOAD_SENSE (1 << 0) + +#define DP_BRANCH_DEVICE_CTRL 0x1a1 +# define DP_BRANCH_DEVICE_IRQ_HPD (1 << 0) + +#define DP_PAYLOAD_ALLOCATE_SET 0x1c0 +#define DP_PAYLOAD_ALLOCATE_START_TIME_SLOT 0x1c1 +#define DP_PAYLOAD_ALLOCATE_TIME_SLOT_COUNT 0x1c2 + +#define DP_SINK_COUNT 0x200 +/* prior to 1.2 bit 7 was reserved mbz */ +# define DP_GET_SINK_COUNT(x) ((((x) & 0x80) >> 1) | ((x) & 0x3f)) +# define DP_SINK_CP_READY (1 << 6) + +#define DP_DEVICE_SERVICE_IRQ_VECTOR 0x201 +# define DP_REMOTE_CONTROL_COMMAND_PENDING (1 << 0) +# define DP_AUTOMATED_TEST_REQUEST (1 << 1) +# define DP_CP_IRQ (1 << 2) +# define DP_MCCS_IRQ (1 << 3) +# define DP_DOWN_REP_MSG_RDY (1 << 4) /* 1.2 MST */ +# define DP_UP_REQ_MSG_RDY (1 << 5) /* 1.2 MST */ +# define DP_SINK_SPECIFIC_IRQ (1 << 6) + #define DP_LANE0_1_STATUS 0x202 #define DP_LANE2_3_STATUS 0x203 # define DP_LANE_CR_DONE (1 << 0) @@ -160,15 +283,135 @@ # define DP_ADJUST_PRE_EMPHASIS_LANE1_MASK 0xc0 # define DP_ADJUST_PRE_EMPHASIS_LANE1_SHIFT 6 +#define DP_TEST_REQUEST 0x218 +# define DP_TEST_LINK_TRAINING (1 << 0) +# define DP_TEST_LINK_VIDEO_PATTERN (1 << 1) +# define DP_TEST_LINK_EDID_READ (1 << 2) +# define DP_TEST_LINK_PHY_TEST_PATTERN (1 << 3) /* DPCD >= 1.1 */ +# define DP_TEST_LINK_FAUX_PATTERN (1 << 4) /* DPCD >= 1.2 */ + +#define DP_TEST_LINK_RATE 0x219 +# define DP_LINK_RATE_162 (0x6) +# define DP_LINK_RATE_27 (0xa) + +#define DP_TEST_LANE_COUNT 0x220 + +#define DP_TEST_PATTERN 0x221 + +#define DP_TEST_CRC_R_CR 0x240 +#define DP_TEST_CRC_G_Y 0x242 +#define DP_TEST_CRC_B_CB 0x244 + +#define DP_TEST_SINK_MISC 0x246 +#define DP_TEST_CRC_SUPPORTED (1 << 5) + +#define DP_TEST_RESPONSE 0x260 +# define DP_TEST_ACK (1 << 0) +# define DP_TEST_NAK (1 << 1) +# define DP_TEST_EDID_CHECKSUM_WRITE (1 << 2) + +#define DP_TEST_EDID_CHECKSUM 0x261 + +#define DP_TEST_SINK 0x270 +#define DP_TEST_SINK_START (1 << 0) + +#define DP_PAYLOAD_TABLE_UPDATE_STATUS 0x2c0 /* 1.2 MST */ +# define DP_PAYLOAD_TABLE_UPDATED (1 << 0) +# define DP_PAYLOAD_ACT_HANDLED (1 << 1) + +#define DP_VC_PAYLOAD_ID_SLOT_1 0x2c1 /* 1.2 MST */ +/* up to ID_SLOT_63 at 0x2ff */ + +#define DP_SOURCE_OUI 0x300 +#define DP_SINK_OUI 0x400 +#define DP_BRANCH_OUI 0x500 + #define DP_SET_POWER 0x600 # define DP_SET_POWER_D0 0x1 # define DP_SET_POWER_D3 0x2 +# define DP_SET_POWER_MASK 0x3 + +#define DP_SIDEBAND_MSG_DOWN_REQ_BASE 0x1000 /* 1.2 MST */ +#define DP_SIDEBAND_MSG_UP_REP_BASE 0x1200 /* 1.2 MST */ +#define DP_SIDEBAND_MSG_DOWN_REP_BASE 0x1400 /* 1.2 MST */ +#define DP_SIDEBAND_MSG_UP_REQ_BASE 0x1600 /* 1.2 MST */ + +#define DP_SINK_COUNT_ESI 0x2002 /* 1.2 */ +/* 0-5 sink count */ +# define DP_SINK_COUNT_CP_READY (1 << 6) + +#define DP_DEVICE_SERVICE_IRQ_VECTOR_ESI0 0x2003 /* 1.2 */ + +#define DP_DEVICE_SERVICE_IRQ_VECTOR_ESI1 0x2004 /* 1.2 */ + +#define DP_LINK_SERVICE_IRQ_VECTOR_ESI0 0x2005 /* 1.2 */ + +#define DP_PSR_ERROR_STATUS 0x2006 /* XXX 1.2? */ +# define DP_PSR_LINK_CRC_ERROR (1 << 0) +# define DP_PSR_RFB_STORAGE_ERROR (1 << 1) + +#define DP_PSR_ESI 0x2007 /* XXX 1.2? */ +# define DP_PSR_CAPS_CHANGE (1 << 0) + +#define DP_PSR_STATUS 0x2008 /* XXX 1.2? */ +# define DP_PSR_SINK_INACTIVE 0 +# define DP_PSR_SINK_ACTIVE_SRC_SYNCED 1 +# define DP_PSR_SINK_ACTIVE_RFB 2 +# define DP_PSR_SINK_ACTIVE_SINK_SYNCED 3 +# define DP_PSR_SINK_ACTIVE_RESYNC 4 +# define DP_PSR_SINK_INTERNAL_ERROR 7 +# define DP_PSR_SINK_STATE_MASK 0x07 + +/* DP 1.2 Sideband message defines */ +/* peer device type - DP 1.2a Table 2-92 */ +#define DP_PEER_DEVICE_NONE 0x0 +#define DP_PEER_DEVICE_SOURCE_OR_SST 0x1 +#define DP_PEER_DEVICE_MST_BRANCHING 0x2 +#define DP_PEER_DEVICE_SST_SINK 0x3 +#define DP_PEER_DEVICE_DP_LEGACY_CONV 0x4 + +/* DP 1.2 MST sideband request names DP 1.2a Table 2-80 */ +#define DP_LINK_ADDRESS 0x01 +#define DP_CONNECTION_STATUS_NOTIFY 0x02 +#define DP_ENUM_PATH_RESOURCES 0x10 +#define DP_ALLOCATE_PAYLOAD 0x11 +#define DP_QUERY_PAYLOAD 0x12 +#define DP_RESOURCE_STATUS_NOTIFY 0x13 +#define DP_CLEAR_PAYLOAD_ID_TABLE 0x14 +#define DP_REMOTE_DPCD_READ 0x20 +#define DP_REMOTE_DPCD_WRITE 0x21 +#define DP_REMOTE_I2C_READ 0x22 +#define DP_REMOTE_I2C_WRITE 0x23 +#define DP_POWER_UP_PHY 0x24 +#define DP_POWER_DOWN_PHY 0x25 +#define DP_SINK_EVENT_NOTIFY 0x30 +#define DP_QUERY_STREAM_ENC_STATUS 0x38 + +/* DP 1.2 MST sideband nak reasons - table 2.84 */ +#define DP_NAK_WRITE_FAILURE 0x01 +#define DP_NAK_INVALID_READ 0x02 +#define DP_NAK_CRC_FAILURE 0x03 +#define DP_NAK_BAD_PARAM 0x04 +#define DP_NAK_DEFER 0x05 +#define DP_NAK_LINK_FAILURE 0x06 +#define DP_NAK_NO_RESOURCES 0x07 +#define DP_NAK_DPCD_FAIL 0x08 +#define DP_NAK_I2C_NAK 0x09 +#define DP_NAK_ALLOCATE_FAIL 0x0a #define MODE_I2C_START 1 #define MODE_I2C_WRITE 2 #define MODE_I2C_READ 4 #define MODE_I2C_STOP 8 +/** + * struct i2c_algo_dp_aux_data - driver interface structure for i2c over dp + * aux algorithm + * @running: set by the algo indicating whether an i2c is ongoing or whether + * the i2c bus is quiescent + * @address: i2c target address for the currently ongoing transfer + * @aux_ch: driver callback to transfer a single byte of the i2c payload + */ struct i2c_algo_dp_aux_data { bool running; u16 address; @@ -180,4 +423,190 @@ struct i2c_algo_dp_aux_data { int i2c_dp_aux_add_bus(struct i2c_adapter *adapter); + +#define DP_LINK_STATUS_SIZE 6 +bool drm_dp_channel_eq_ok(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count); +bool drm_dp_clock_recovery_ok(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane_count); +u8 drm_dp_get_adjust_request_voltage(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane); +u8 drm_dp_get_adjust_request_pre_emphasis(const u8 link_status[DP_LINK_STATUS_SIZE], + int lane); + +#define DP_RECEIVER_CAP_SIZE 0xf +#define EDP_PSR_RECEIVER_CAP_SIZE 2 + +void drm_dp_link_train_clock_recovery_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]); +void drm_dp_link_train_channel_eq_delay(const u8 dpcd[DP_RECEIVER_CAP_SIZE]); + +u8 drm_dp_link_rate_to_bw_code(int link_rate); +int drm_dp_bw_code_to_link_rate(u8 link_bw); + +struct edp_sdp_header { + u8 HB0; /* Secondary Data Packet ID */ + u8 HB1; /* Secondary Data Packet Type */ + u8 HB2; /* 7:5 reserved, 4:0 revision number */ + u8 HB3; /* 7:5 reserved, 4:0 number of valid data bytes */ +} __packed; + +#define EDP_SDP_HEADER_REVISION_MASK 0x1F +#define EDP_SDP_HEADER_VALID_PAYLOAD_BYTES 0x1F + +struct edp_vsc_psr { + struct edp_sdp_header sdp_header; + u8 DB0; /* Stereo Interface */ + u8 DB1; /* 0 - PSR State; 1 - Update RFB; 2 - CRC Valid */ + u8 DB2; /* CRC value bits 7:0 of the R or Cr component */ + u8 DB3; /* CRC value bits 15:8 of the R or Cr component */ + u8 DB4; /* CRC value bits 7:0 of the G or Y component */ + u8 DB5; /* CRC value bits 15:8 of the G or Y component */ + u8 DB6; /* CRC value bits 7:0 of the B or Cb component */ + u8 DB7; /* CRC value bits 15:8 of the B or Cb component */ + u8 DB8_31[24]; /* Reserved */ +} __packed; + +#define EDP_VSC_PSR_STATE_ACTIVE (1<<0) +#define EDP_VSC_PSR_UPDATE_RFB (1<<1) +#define EDP_VSC_PSR_CRC_VALUES_VALID (1<<2) + +static inline int +drm_dp_max_link_rate(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + return drm_dp_bw_code_to_link_rate(dpcd[DP_MAX_LINK_RATE]); +} + +static inline u8 +drm_dp_max_lane_count(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + return dpcd[DP_MAX_LANE_COUNT] & DP_MAX_LANE_COUNT_MASK; +} + +static inline bool +drm_dp_enhanced_frame_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) +{ + return dpcd[DP_DPCD_REV] >= 0x11 && + (dpcd[DP_MAX_LANE_COUNT] & DP_ENHANCED_FRAME_CAP); +} + +/* + * DisplayPort AUX channel + */ + +/** + * struct drm_dp_aux_msg - DisplayPort AUX channel transaction + * @address: address of the (first) register to access + * @request: contains the type of transaction (see DP_AUX_* macros) + * @reply: upon completion, contains the reply type of the transaction + * @buffer: pointer to a transmission or reception buffer + * @size: size of @buffer + */ +struct drm_dp_aux_msg { + unsigned int address; + u8 request; + u8 reply; + void *buffer; + size_t size; +}; + +/** + * struct drm_dp_aux - DisplayPort AUX channel + * @name: user-visible name of this AUX channel and the I2C-over-AUX adapter + * @ddc: I2C adapter that can be used for I2C-over-AUX communication + * @dev: pointer to struct device that is the parent for this AUX channel + * @hw_mutex: internal mutex used for locking transfers + * @transfer: transfers a message representing a single AUX transaction + * + * The .dev field should be set to a pointer to the device that implements + * the AUX channel. + * + * The .name field may be used to specify the name of the I2C adapter. If set to + * NULL, dev_name() of .dev will be used. + * + * Drivers provide a hardware-specific implementation of how transactions + * are executed via the .transfer() function. A pointer to a drm_dp_aux_msg + * structure describing the transaction is passed into this function. Upon + * success, the implementation should return the number of payload bytes + * that were transferred, or a negative error-code on failure. Helpers + * propagate errors from the .transfer() function, with the exception of + * the -EBUSY error, which causes a transaction to be retried. On a short, + * helpers will return -EPROTO to make it simpler to check for failure. + * + * An AUX channel can also be used to transport I2C messages to a sink. A + * typical application of that is to access an EDID that's present in the + * sink device. The .transfer() function can also be used to execute such + * transactions. The drm_dp_aux_register_i2c_bus() function registers an + * I2C adapter that can be passed to drm_probe_ddc(). Upon removal, drivers + * should call drm_dp_aux_unregister_i2c_bus() to remove the I2C adapter. + * + * Note that the aux helper code assumes that the .transfer() function + * only modifies the reply field of the drm_dp_aux_msg structure. The + * retry logic and i2c helpers assume this is the case. + */ +struct drm_dp_aux { + const char *name; + struct i2c_adapter ddc; + struct device *dev; + struct mutex hw_mutex; + ssize_t (*transfer)(struct drm_dp_aux *aux, + struct drm_dp_aux_msg *msg); +}; + +ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, + void *buffer, size_t size); +ssize_t drm_dp_dpcd_write(struct drm_dp_aux *aux, unsigned int offset, + void *buffer, size_t size); + +/** + * drm_dp_dpcd_readb() - read a single byte from the DPCD + * @aux: DisplayPort AUX channel + * @offset: address of the register to read + * @valuep: location where the value of the register will be stored + * + * Returns the number of bytes transferred (1) on success, or a negative + * error code on failure. + */ +static inline ssize_t drm_dp_dpcd_readb(struct drm_dp_aux *aux, + unsigned int offset, u8 *valuep) +{ + return drm_dp_dpcd_read(aux, offset, valuep, 1); +} + +/** + * drm_dp_dpcd_writeb() - write a single byte to the DPCD + * @aux: DisplayPort AUX channel + * @offset: address of the register to write + * @value: value to write to the register + * + * Returns the number of bytes transferred (1) on success, or a negative + * error code on failure. + */ +static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux, + unsigned int offset, u8 value) +{ + return drm_dp_dpcd_write(aux, offset, &value, 1); +} + +int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux, + u8 status[DP_LINK_STATUS_SIZE]); + +/* + * DisplayPort link + */ +#define DP_LINK_CAP_ENHANCED_FRAMING (1 << 0) + +struct drm_dp_link { + unsigned char revision; + unsigned int rate; + unsigned int num_lanes; + unsigned long capabilities; +}; + +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_configure(struct drm_dp_aux *aux, struct drm_dp_link *link); + +int drm_dp_aux_register(struct drm_dp_aux *aux); +void drm_dp_aux_unregister(struct drm_dp_aux *aux); + #endif /* _DRM_DP_HELPER_H_ */ |