diff options
Diffstat (limited to 'include/drm/drm_dp_helper.h')
| -rw-r--r-- | include/drm/drm_dp_helper.h | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 1d09050a8c00..cfcacec5b89d 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -279,11 +279,21 @@ #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_SINK 0x270 +#define DP_TEST_SINK_START (1 << 0) + #define DP_SOURCE_OUI 0x300 #define DP_SINK_OUI 0x400 #define DP_BRANCH_OUI 0x500 @@ -291,6 +301,7 @@ #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_PSR_ERROR_STATUS 0x2006 /* XXX 1.2? */ # define DP_PSR_LINK_CRC_ERROR (1 << 0) @@ -398,4 +409,122 @@ drm_dp_enhanced_frame_cap(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) (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 + * @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 + * @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; + + 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_i2c_bus(struct drm_dp_aux *aux); +void drm_dp_aux_unregister_i2c_bus(struct drm_dp_aux *aux); + #endif /* _DRM_DP_HELPER_H_ */ |