diff options
Diffstat (limited to 'include/drm/drm_dp_helper.h')
| -rw-r--r-- | include/drm/drm_dp_helper.h | 175 |
1 files changed, 142 insertions, 33 deletions
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h index 3f2715eb965f..1d5b3dbb6e56 100644 --- a/include/drm/drm_dp_helper.h +++ b/include/drm/drm_dp_helper.h @@ -30,6 +30,7 @@ struct drm_device; struct drm_dp_aux; +struct drm_panel; /* * Unless otherwise noted, all values are from the DP 1.1a spec. Note that @@ -1818,6 +1819,24 @@ drm_dp_sink_can_do_video_without_timing_msa(const u8 dpcd[DP_RECEIVER_CAP_SIZE]) DP_MSA_TIMING_PAR_IGNORED; } +/** + * drm_edp_backlight_supported() - Check an eDP DPCD for VESA backlight support + * @edp_dpcd: The DPCD to check + * + * Note that currently this function will return %false for panels which support various DPCD + * backlight features but which require the brightness be set through PWM, and don't support setting + * the brightness level via the DPCD. This is a TODO. + * + * Returns: %True if @edp_dpcd indicates that VESA backlight controls are supported, %false + * otherwise + */ +static inline bool +drm_edp_backlight_supported(const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]) +{ + return (edp_dpcd[1] & DP_EDP_TCON_BACKLIGHT_ADJUSTMENT_CAP) && + (edp_dpcd[2] & DP_EDP_BACKLIGHT_BRIGHTNESS_AUX_SET_CAP); +} + /* * DisplayPort AUX channel */ @@ -1858,35 +1877,6 @@ struct drm_dp_aux_cec { /** * 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 - * @drm_dev: pointer to the &drm_device that owns this AUX channel. Beware, this - * may be %NULL before drm_dp_aux_register() has been called. - * @crtc: backpointer to the crtc that is currently using this AUX channel - * @hw_mutex: internal mutex used for locking transfers - * @crc_work: worker that captures CRCs for each frame - * @crc_count: counter of captured frame CRCs - * @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. As well, the @drm_dev field should be set to the &drm_device - * that will be using this AUX channel as early as possible. For many graphics - * drivers this should happen before drm_dp_aux_init(), however it's perfectly - * fine to set this field later so long as it's assigned before calling - * drm_dp_aux_register(). - * - * 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 @@ -1897,22 +1887,96 @@ struct drm_dp_aux_cec { * transfers by default; if a partial response is received, the adapter will * drop down to the size given by the partial response for this transaction * only. - * - * 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 { + /** + * @name: user-visible name of this AUX channel and the + * I2C-over-AUX adapter. + * + * It's also used to specify the name of the I2C adapter. If set + * to %NULL, dev_name() of @dev will be used. + */ const char *name; + + /** + * @ddc: I2C adapter that can be used for I2C-over-AUX + * communication + */ struct i2c_adapter ddc; + + /** + * @dev: pointer to struct device that is the parent for this + * AUX channel. + */ struct device *dev; + + /** + * @drm_dev: pointer to the &drm_device that owns this AUX channel. + * Beware, this may be %NULL before drm_dp_aux_register() has been + * called. + * + * It should be set to the &drm_device that will be using this AUX + * channel as early as possible. For many graphics drivers this should + * happen before drm_dp_aux_init(), however it's perfectly fine to set + * this field later so long as it's assigned before calling + * drm_dp_aux_register(). + */ struct drm_device *drm_dev; + + /** + * @crtc: backpointer to the crtc that is currently using this + * AUX channel + */ struct drm_crtc *crtc; + + /** + * @hw_mutex: internal mutex used for locking transfers. + * + * Note that if the underlying hardware is shared among multiple + * channels, the driver needs to do additional locking to + * prevent concurrent access. + */ struct mutex hw_mutex; + + /** + * @crc_work: worker that captures CRCs for each frame + */ struct work_struct crc_work; + + /** + * @crc_count: counter of captured frame CRCs + */ u8 crc_count; + + /** + * @transfer: transfers a message representing a single AUX + * transaction. + * + * This is a hardware-specific implementation of how + * transactions are executed that the drivers must provide. + * + * 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 will propagate these errors, 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. + * + * The @transfer() function must only modify the reply field of + * the &drm_dp_aux_msg structure. The retry logic and i2c + * helpers assume this is the case. + * + * Also note that this callback can be called no matter the + * state @dev is in. Drivers that need that device to be powered + * to perform this operation will first need to make sure it's + * been properly enabled. + */ ssize_t (*transfer)(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg); + /** * @i2c_nack_count: Counts I2C NACKs, used for DP validation. */ @@ -2124,6 +2188,51 @@ drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk) return desc->quirks & BIT(quirk); } +/** + * struct drm_edp_backlight_info - Probed eDP backlight info struct + * @pwmgen_bit_count: The pwmgen bit count + * @pwm_freq_pre_divider: The PWM frequency pre-divider value being used for this backlight, if any + * @max: The maximum backlight level that may be set + * @lsb_reg_used: Do we also write values to the DP_EDP_BACKLIGHT_BRIGHTNESS_LSB register? + * @aux_enable: Does the panel support the AUX enable cap? + * + * This structure contains various data about an eDP backlight, which can be populated by using + * drm_edp_backlight_init(). + */ +struct drm_edp_backlight_info { + u8 pwmgen_bit_count; + u8 pwm_freq_pre_divider; + u16 max; + + bool lsb_reg_used : 1; + bool aux_enable : 1; +}; + +int +drm_edp_backlight_init(struct drm_dp_aux *aux, struct drm_edp_backlight_info *bl, + u16 driver_pwm_freq_hz, const u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE], + u16 *current_level, u8 *current_mode); +int drm_edp_backlight_set_level(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level); +int drm_edp_backlight_enable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl, + u16 level); +int drm_edp_backlight_disable(struct drm_dp_aux *aux, const struct drm_edp_backlight_info *bl); + +#if IS_ENABLED(CONFIG_DRM_KMS_HELPER) && (IS_BUILTIN(CONFIG_BACKLIGHT_CLASS_DEVICE) || \ + (IS_MODULE(CONFIG_DRM_KMS_HELPER) && IS_MODULE(CONFIG_BACKLIGHT_CLASS_DEVICE))) + +int drm_panel_dp_aux_backlight(struct drm_panel *panel, struct drm_dp_aux *aux); + +#else + +static inline int drm_panel_dp_aux_backlight(struct drm_panel *panel, + struct drm_dp_aux *aux) +{ + return 0; +} + +#endif + #ifdef CONFIG_DRM_DP_CEC void drm_dp_cec_irq(struct drm_dp_aux *aux); void drm_dp_cec_register_connector(struct drm_dp_aux *aux, |