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authorDave Airlie <airlied@redhat.com>2015-06-04 09:17:45 +1000
committerDave Airlie <airlied@redhat.com>2015-06-04 09:17:45 +1000
commit531e63e163072e325d9cc82acc095a009f07b6ef (patch)
treeb5b63cc6996b172658e3e1f2b0ce00d4aa686465 /drivers/gpu/drm/drm_bridge.c
parentMerge tag 'drm-amdkfd-next-2015-06-03' of git://people.freedesktop.org/~gabbayo/linux into drm-next (diff)
parentdrm: Fix off-by-one in vblank hardware counter wraparound handling (diff)
downloadlinux-dev-531e63e163072e325d9cc82acc095a009f07b6ef.tar.xz
linux-dev-531e63e163072e325d9cc82acc095a009f07b6ef.zip
Merge tag 'topic/drm-misc-2015-05-27' of git://anongit.freedesktop.org/drm-intel into drm-next
One more round of drm-misc, again mostly atomic. Big thing is the userspace blob code from Daniel Stone, with support for the mode_id blob now added to the atomic ioctl. Finally we can do atomic modesets! Note that the atomic ioctl is still behind the module knob since the weston patches aren't quite ready yet imo - they lack TEST_ONLY support, which is a fairly crucial bit of the atomic api. But besides that I think it's all good to go. That's also why we didn't bother to hide the new blob ioctls behind the knob, that part won't need to change. And if weston patches get in shape in time we could throw the "atomic by default patch" on top for 4.2. * tag 'topic/drm-misc-2015-05-27' of git://anongit.freedesktop.org/drm-intel: drm: Fix off-by-one in vblank hardware counter wraparound handling drm/atomic: fix out of bounds read in for_each_*_in_state helpers drm/atomic: Add MODE_ID property drm/atomic: Add current-mode blob to CRTC state drm: Add drm_atomic_set_mode_for_crtc drm: check for garbage in unused addfb2 fields drm: Retain reference to blob properties in lookup drm/mode: Add user blob-creation ioctl drm: Return error value from blob creation drm: Allow creating blob properties without copy drm/mode: Unstatic kernel-userspace mode conversion drm/mode: Validate modes inside drm_crtc_convert_umode drm/crtc_helper: Replace open-coded CRTC state helpers drm: kerneldoc fixes for blob properties drm/DocBook: Add more drm_bridge documentation drm: bridge: Allow daisy chaining of bridges drm/atomic: add all affected planes in drm_atomic_helper_check_modeset drm/atomic: add drm_atomic_add_affected_planes drm/atomic: add commit_planes_on_crtc helper
Diffstat (limited to 'drivers/gpu/drm/drm_bridge.c')
-rw-r--r--drivers/gpu/drm/drm_bridge.c242
1 files changed, 242 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index eaa5790c2a6f..6b8f7211e543 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -28,9 +28,42 @@
#include "drm/drmP.h"
+/**
+ * DOC: overview
+ *
+ * drm_bridge represents a device that hangs on to an encoder. These are handy
+ * when a regular drm_encoder entity isn't enough to represent the entire
+ * encoder chain.
+ *
+ * A bridge is always associated to a single drm_encoder at a time, but can be
+ * either connected to it directly, or through an intermediate bridge:
+ *
+ * encoder ---> bridge B ---> bridge A
+ *
+ * Here, the output of the encoder feeds to bridge B, and that furthers feeds to
+ * bridge A.
+ *
+ * The driver using the bridge is responsible to make the associations between
+ * the encoder and bridges. Once these links are made, the bridges will
+ * participate along with encoder functions to perform mode_set/enable/disable
+ * through the ops provided in drm_bridge_funcs.
+ *
+ * drm_bridge, like drm_panel, aren't drm_mode_object entities like planes,
+ * crtcs, encoders or connectors. They just provide additional hooks to get the
+ * desired output at the end of the encoder chain.
+ */
+
static DEFINE_MUTEX(bridge_lock);
static LIST_HEAD(bridge_list);
+/**
+ * drm_bridge_add - add the given bridge to the global bridge list
+ *
+ * @bridge: bridge control structure
+ *
+ * RETURNS:
+ * Unconditionally returns Zero.
+ */
int drm_bridge_add(struct drm_bridge *bridge)
{
mutex_lock(&bridge_lock);
@@ -41,6 +74,11 @@ int drm_bridge_add(struct drm_bridge *bridge)
}
EXPORT_SYMBOL(drm_bridge_add);
+/**
+ * drm_bridge_remove - remove the given bridge from the global bridge list
+ *
+ * @bridge: bridge control structure
+ */
void drm_bridge_remove(struct drm_bridge *bridge)
{
mutex_lock(&bridge_lock);
@@ -49,6 +87,21 @@ void drm_bridge_remove(struct drm_bridge *bridge)
}
EXPORT_SYMBOL(drm_bridge_remove);
+/**
+ * drm_bridge_attach - associate given bridge to our DRM device
+ *
+ * @dev: DRM device
+ * @bridge: bridge control structure
+ *
+ * called by a kms driver to link one of our encoder/bridge to the given
+ * bridge.
+ *
+ * Note that setting up links between the bridge and our encoder/bridge
+ * objects needs to be handled by the kms driver itself
+ *
+ * RETURNS:
+ * Zero on success, error code on failure
+ */
int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge)
{
if (!dev || !bridge)
@@ -66,7 +119,196 @@ int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge)
}
EXPORT_SYMBOL(drm_bridge_attach);
+/**
+ * DOC: bridge callbacks
+ *
+ * The drm_bridge_funcs ops are populated by the bridge driver. The drm
+ * internals(atomic and crtc helpers) use the helpers defined in drm_bridge.c
+ * These helpers call a specific drm_bridge_funcs op for all the bridges
+ * during encoder configuration.
+ *
+ * When creating a bridge driver, one can implement drm_bridge_funcs op with
+ * the help of these rough rules:
+ *
+ * pre_enable: this contains things needed to be done for the bridge before
+ * its clock and timings are enabled by its source. For a bridge, its source
+ * is generally the encoder or bridge just before it in the encoder chain.
+ *
+ * enable: this contains things needed to be done for the bridge once its
+ * source is enabled. In other words, enable is called once the source is
+ * ready with clock and timing needed by the bridge.
+ *
+ * disable: this contains things needed to be done for the bridge assuming
+ * that its source is still enabled, i.e. clock and timings are still on.
+ *
+ * post_disable: this contains things needed to be done for the bridge once
+ * its source is disabled, i.e. once clocks and timings are off.
+ *
+ * mode_fixup: this should fixup the given mode for the bridge. It is called
+ * after the encoder's mode fixup. mode_fixup can also reject a mode completely
+ * if it's unsuitable for the hardware.
+ *
+ * mode_set: this sets up the mode for the bridge. It assumes that its source
+ * (an encoder or a bridge) has set the mode too.
+ */
+
+/**
+ * drm_bridge_mode_fixup - fixup proposed mode for all bridges in the
+ * encoder chain
+ * @bridge: bridge control structure
+ * @mode: desired mode to be set for the bridge
+ * @adjusted_mode: updated mode that works for this bridge
+ *
+ * Calls 'mode_fixup' drm_bridge_funcs op for all the bridges in the
+ * encoder chain, starting from the first bridge to the last.
+ *
+ * Note: the bridge passed should be the one closest to the encoder
+ *
+ * RETURNS:
+ * true on success, false on failure
+ */
+bool drm_bridge_mode_fixup(struct drm_bridge *bridge,
+ const struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ bool ret = true;
+
+ if (!bridge)
+ return true;
+
+ if (bridge->funcs->mode_fixup)
+ ret = bridge->funcs->mode_fixup(bridge, mode, adjusted_mode);
+
+ ret = ret && drm_bridge_mode_fixup(bridge->next, mode, adjusted_mode);
+
+ return ret;
+}
+EXPORT_SYMBOL(drm_bridge_mode_fixup);
+
+/**
+ * drm_bridge_disable - calls 'disable' drm_bridge_funcs op for all
+ * bridges in the encoder chain.
+ * @bridge: bridge control structure
+ *
+ * Calls 'disable' drm_bridge_funcs op for all the bridges in the encoder
+ * chain, starting from the last bridge to the first. These are called before
+ * calling the encoder's prepare op.
+ *
+ * Note: the bridge passed should be the one closest to the encoder
+ */
+void drm_bridge_disable(struct drm_bridge *bridge)
+{
+ if (!bridge)
+ return;
+
+ drm_bridge_disable(bridge->next);
+
+ bridge->funcs->disable(bridge);
+}
+EXPORT_SYMBOL(drm_bridge_disable);
+
+/**
+ * drm_bridge_post_disable - calls 'post_disable' drm_bridge_funcs op for
+ * all bridges in the encoder chain.
+ * @bridge: bridge control structure
+ *
+ * Calls 'post_disable' drm_bridge_funcs op for all the bridges in the
+ * encoder chain, starting from the first bridge to the last. These are called
+ * after completing the encoder's prepare op.
+ *
+ * Note: the bridge passed should be the one closest to the encoder
+ */
+void drm_bridge_post_disable(struct drm_bridge *bridge)
+{
+ if (!bridge)
+ return;
+
+ bridge->funcs->post_disable(bridge);
+
+ drm_bridge_post_disable(bridge->next);
+}
+EXPORT_SYMBOL(drm_bridge_post_disable);
+
+/**
+ * drm_bridge_mode_set - set proposed mode for all bridges in the
+ * encoder chain
+ * @bridge: bridge control structure
+ * @mode: desired mode to be set for the bridge
+ * @adjusted_mode: updated mode that works for this bridge
+ *
+ * Calls 'mode_set' drm_bridge_funcs op for all the bridges in the
+ * encoder chain, starting from the first bridge to the last.
+ *
+ * Note: the bridge passed should be the one closest to the encoder
+ */
+void drm_bridge_mode_set(struct drm_bridge *bridge,
+ struct drm_display_mode *mode,
+ struct drm_display_mode *adjusted_mode)
+{
+ if (!bridge)
+ return;
+
+ if (bridge->funcs->mode_set)
+ bridge->funcs->mode_set(bridge, mode, adjusted_mode);
+
+ drm_bridge_mode_set(bridge->next, mode, adjusted_mode);
+}
+EXPORT_SYMBOL(drm_bridge_mode_set);
+
+/**
+ * drm_bridge_pre_enable - calls 'pre_enable' drm_bridge_funcs op for all
+ * bridges in the encoder chain.
+ * @bridge: bridge control structure
+ *
+ * Calls 'pre_enable' drm_bridge_funcs op for all the bridges in the encoder
+ * chain, starting from the last bridge to the first. These are called
+ * before calling the encoder's commit op.
+ *
+ * Note: the bridge passed should be the one closest to the encoder
+ */
+void drm_bridge_pre_enable(struct drm_bridge *bridge)
+{
+ if (!bridge)
+ return;
+
+ drm_bridge_pre_enable(bridge->next);
+
+ bridge->funcs->pre_enable(bridge);
+}
+EXPORT_SYMBOL(drm_bridge_pre_enable);
+
+/**
+ * drm_bridge_enable - calls 'enable' drm_bridge_funcs op for all bridges
+ * in the encoder chain.
+ * @bridge: bridge control structure
+ *
+ * Calls 'enable' drm_bridge_funcs op for all the bridges in the encoder
+ * chain, starting from the first bridge to the last. These are called
+ * after completing the encoder's commit op.
+ *
+ * Note that the bridge passed should be the one closest to the encoder
+ */
+void drm_bridge_enable(struct drm_bridge *bridge)
+{
+ if (!bridge)
+ return;
+
+ bridge->funcs->enable(bridge);
+
+ drm_bridge_enable(bridge->next);
+}
+EXPORT_SYMBOL(drm_bridge_enable);
+
#ifdef CONFIG_OF
+/**
+ * of_drm_find_bridge - find the bridge corresponding to the device node in
+ * the global bridge list
+ *
+ * @np: device node
+ *
+ * RETURNS:
+ * drm_bridge control struct on success, NULL on failure
+ */
struct drm_bridge *of_drm_find_bridge(struct device_node *np)
{
struct drm_bridge *bridge;