X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=blobdiff_plain;f=include%2Fdrm%2Fdrm_dp_helper.h;h=1d5b3dbb6e563f3da9384bbe9c01f41ec7622a80;hp=3f2715eb965f7931d94117fc88da0f98808b9cbc;hb=588b3eee528873d73bf777f329d35b2e65e24777;hpb=2bb919b62f6e5959552a90a399d09d683afa3d1d

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,