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* drm/dp: Add a drm_aux-dev module for reading/writing dpcd registers.Rafael Antognolli2016-02-121-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This module is heavily based on i2c-dev. Once loaded, it provides one dev node per DP AUX channel, named drm_dp_auxN, where N is an integer. It's possible to know which connector owns this aux channel by looking at the respective sysfs /sys/class/drm_aux_dev/drm_dp_auxN/connector, if the connector device pointer was correctly set in the aux helper struct. Two main operations are provided on the registers read and write. The address of the register to be read or written is given using lseek. The seek position is updated upon read or write. v2: - lseek is used to select the register to read/write - read/write are used instead of ioctl - no blocking_notifier is used, just a direct callback v3: - use drm_dp_aux_dev prefix for public functions - chardev is named drm_dp_auxN - read/write don't allocate a buffer anymore, and transfer up to 16 bytes a time - remove notifier list from the implementation - option on menuconfig is now a boolean - add inline stub functions to avoid breakage when this option is disabled v4: - fix build system changes - actually disable this module when not selected. v5: - Use kref to avoid device closing while still in use - Don't use list, use an idr for storing aux_dev - Remove "connector" attribute - set aux.dev to the connector drm_connector device, instead of drm_device v6: - Use atomic_t for usage count - Use a mutex instead of spinlock for idr lock - Destroy chardev immediately on unregister - other minor suggestions from Ville v7: - style fixes - error handling fixes v8: - more error handling fixes v9: - remove module_init and module_exit, and add drm_dp_aux_dev_init/exit to drm_kms_helper_init/exit. Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/1453417821-2811-3-git-send-email-rafael.antognolli@intel.com
* Merge tag 'v4.3-rc2' into topic/drm-miscDaniel Vetter2015-09-241-5/+95
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Backmerge Linux 4.3-rc2 because of conflicts in the dp helper code between bugfixes and new code. Just adjacent lines really. On top of that there's a silent conflict in the new fsl-dcu driver merged into 4.3 and commit 844f9111f6f54f88eb2f0fac121b82ce77193866 Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Date: Wed Sep 2 10:42:40 2015 +0200 drm/atomic: Make prepare_fb/cleanup_fb only take state, v3. which Thierry Reding spotted and provided a fixup for. Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
| * drm/dp: Add dp_aux_i2c_speed_khz module param to set the assume i2c bus speedVille Syrjälä2015-09-021-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | To help with debugging i2c-over-aux issues, add a module parameter than can be used to tweak the assumed i2c bus speed, and thus the maximum number of retries we will do for each aux message. Cc: Simon Farnsworth <simon.farnsworth@onelan.com> Cc: moosotc@gmail.com Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
| * drm/dp: Adjust i2c-over-aux retry count based on message size and i2c bus speedVille Syrjälä2015-09-021-2/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Calculate the number of retries we should do for each i2c-over-aux message based on the time it takes to perform the i2c transfer vs. the aux transfer. We assume the shortest possible length for the aux transfer, and the longest possible (exluding clock stretching) for the i2c transfer. The DP spec has some examples on how to calculate this, but we don't calculate things quite the same way. The spec doesn't account for the retry interval (assumes immediate retry on defer), and doesn't assume the best/worst case behaviour as we do. Note that currently we assume 10 kHz speed for the i2c bus. Some real world devices (eg. some Apple DP->VGA dongle) fails with less than 16 retries. and that would correspond to something close to 15 kHz (with our method of calculating things) But let's just go for 10 kHz to be on the safe side. Ideally we should query/set the i2c bus speed via DPCD but for now this should at leaast remove the regression from the 1->16 byte trasnfer size change. And of course if the sink completes the transfer quicker this shouldn't slow things down since we don't change the interval between retries. I did a few experiments with a DP->DVI dongle I have that allows you to change the i2c bus speed. Here are the results of me changing the actual bus speed and the assumed bus speed and seeing when we start to fail the operation: actual i2c khz assumed i2c khz max retries 1 1 ok -> 2 fail 211 ok -> 106 fail 5 8 ok -> 9 fail 27 ok -> 24 fail 10 17 ok -> 18 fail 13 ok -> 12 fail 100 210 ok -> 211 fail 2 ok -> 1 fail So based on that we have a fairly decent safety margin baked into the formula to calculate the max number of retries. Fixes a regression with some DP dongles from: commit 1d002fa720738bcd0bddb9178e9ea0773288e1dd Author: Simon Farnsworth <simon.farnsworth@onelan.co.uk> Date: Tue Feb 10 18:38:08 2015 +0000 drm/dp: Use large transactions for I2C over AUX v2: Use best case for AUX and worst case for i2c (Simon Farnsworth) Add a define our AUX retry interval and account for it v3: Make everything usecs to avoid confusion about units (Daniel) Add a comment reminding people about the AUX bitrate (Daniel) Use DIV_ROUND_UP() since we're after the "worst" case for i2c Cc: Simon Farnsworth <simon.farnsworth@onelan.com> Cc: moosotc@gmail.com Tested-by: moosotc@gmail.com Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91451 Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
| * drm/dp: Define AUX_RETRY_INTERVAL as 500 usVille Syrjälä2015-09-021-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we react to native and i2c defers by waiting either 400-500 us or 500-600 us, depending on which code path we take. Consolidate them all to one define AUX_RETRY_INTERVAL which defines the minimum interval. Since we've been using two different intervals pick the longer of them and define AUX_RETRY_INTERVAL as 500 us. For the maximum just use AUX_RETRY_INTERVAL+100 us. I want to have a define for this so that I can use it when calculating the estimated duration of i2c-over-aux transfers. Without a define it would be very easy to change the sleep duration and neglect to update the i2c-over-aux estimates. Cc: Simon Farnsworth <simon.farnsworth@onelan.com> Cc: moosotc@gmail.com Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
* | drm/dp: Use I2C_WRITE_STATUS_UPDATE to drain partial I2C_WRITE requestsVille Syrjälä2015-09-081-4/+39
|/ | | | | | | | | | | | | | | When an i2c WRITE gets an i2c defer or short i2c ack reply, we are supposed to switch the request from I2C_WRITE to I2C_WRITE_STATUS_UPDATE when we continue to poll for the completion of the request. v2: Don't assume DP_AUX_I2C_WRITE is 0 even though it is, to make the code more obvious to the casual reader (Jani) Acked-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> [danvet: Resolve conflict due to changed context.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: Fix for DP CTS test 4.2.2.5 - I2C DEFER handlingTodd Previte2015-04-201-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For test 4.2.2.5 to pass per the Link CTS Core 1.2 rev1.1 spec, the source device must attempt at least 7 times to read the EDID when it receives an I2C defer. The normal DRM code makes only 7 retries, regardless of whether or not the response is a native defer or an I2C defer. Test 4.2.2.5 fails since there are native defers interspersed with the I2C defers which results in less than 7 EDID read attempts. The solution is to add the numer of defers to the retry counter when an I2C DEFER is returned such that another read attempt will be made. This situation should normally only occur in compliance testing, however, as a worse case real-world scenario, it would result in 13 attempts ( 6 native defers, 7 I2C defers) for a single transaction to complete. The net result is a slightly slower response to an EDID read that shouldn't significantly impact overall performance. V2: - Added a check on the number of I2C Defers to limit the number of times that the retries variable will be decremented. This is to address review feedback regarding possible infinite loops from misbehaving sink devices. V3: - Fixed the limit value to 7 instead of 8 to get the correct retry count. - Combined the increment of the defer count into the if-statement V4: - Removed i915 tag from subject as the patch is not i915-specific V5: - Updated the for-loop to add the number of i2c defers to the retry counter such that the correct number of retry attempts will be made Signed-off-by: Todd Previte <tprevite@gmail.com> Cc: dri-devel@lists.freedesktop.org Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: Fix the 'native defer' message in drm_dp_i2c_do_msg()Todd Previte2015-04-161-1/+1
| | | | | | | | | | | | The debug message is missing a newline at the end and it makes the logs hard to read when a device defers a lot. Simple 2-character fix adds the newline at the end. Signed-off-by: Todd Previte <tprevite@gmail.com> Cc: dri-devel@lists.freedesktop.org Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp: Print the number of bytes processed for aux nacksVille Syrjälä2015-03-231-2/+2
| | | | | | | | | | | | | | When doing a native or i2c aux write the sink will indicate the number of bytes written even if it the nacks the transfer. When we receive a nack we just return an error upwards, but it might still be interesting to see how many bytes made it before the nack. So include that information in the debug messages. v2: Also print the message size (Jani) Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp: Use large transactions for I2C over AUXSimon Farnsworth2015-03-111-18/+58
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Older DisplayPort to DVI-D Dual Link adapters designed by Bizlink have bugs in their I2C over AUX implementation (fixed in newer revisions). They work fine with Windows, but fail with Linux. It turns out that they cannot keep an I2C transaction open unless the previous read was 16 bytes; shorter reads can only be followed by a zero byte transfer ending the I2C transaction. Copy Windows's behaviour, and read 16 bytes at a time. If we get a short reply, assume that there's a hardware bottleneck, and shrink our read size to match. For this purpose, use the algorithm in the DisplayPort 1.2 spec, in the hopes that it'll be closest to what Windows does. Also provide an unsafe module parameter for testing smaller transfer sizes, in case there are sinks out there that cannot work with Windows. Note also that despite the previous comment in drm_dp_i2c_xfer, this speeds up native DP EDID reads; Ville Syrjälä <ville.syrjala@linux.intel.com> found the following changes in his testing: Device under test: old -> with this patch DP->DVI (OUI 001cf8): 40ms -> 35ms DP->VGA (OUI 0022b9): 45ms -> 38ms Zotac DP->2xHDMI: 25ms -> 4ms Asus PB278 monitor: 22ms -> 3ms A back of the envelope calculation shows that peak theoretical transfer rate for 1 byte reads is around 60 kbit/s; with 16 byte reads, this increases to around 500 kbit/s, which explains the increase in speed. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55228 Tested-by: Aidan Marks <aidanamarks@gmail.com> (v3) Signed-off-by: Simon Farnsworth <simon.farnsworth@onelan.co.uk> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp: add drm_dp_link_power_down() helperRob Clark2015-02-011-0/+31
| | | | | | | | We had _power_up(), but drivers also need to be able to power down. Signed-off-by: Rob Clark <robdclark@gmail.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
* drm/dp: retry AUX transactions 32 times (v1.1)Dave Airlie2014-12-091-3/+4
| | | | | | | | | | | | | | | | At least on two MST devices I've tested with, when they are link training downstream, they are totally unable to handle aux ch msgs, so they defer like nuts. I tried 16, it wasn't enough, 32 seems better. This fixes one Dell 4k monitor and one of the MST hubs. v1.1: fixup comment (Tom). Acked-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm/dp: Add counters in the drm_dp_aux struct for I2C NACKs and DEFERsTodd Previte2014-11-051-0/+2
| | | | | | | | | | | | | | | | | | These counters are used for Displayort compliance testing to detect error conditions when executing tests 4.2.2.4 and 4.2.2.5 in the Displayport Link CTS specificaiton. They determine whether to use the preferred/requested mode or the failsafe mode during these tests. V2: - Addressed previous review feedback - Updated commit message - Changed from uint8_t to uint32_t Cc: dri-devel@lists.freedesktop.org Signed-off-by: Todd Previte <tprevite@gmail.com> [danvet: s/uint32_t/unsigned/ for clearer intent. Also drop the i915 from the subject, it's all core stuff.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp-helper: Move the legacy helpers to gma500Daniel Vetter2014-10-231-192/+0
| | | | | | | | | | | | | | | | Except for gma500 all drivers are converted to the new style helpers, which have much better abstraction of the underlying hw protocols and already much more helper functions (including the entire mst library) on top of them. Since no one seems to work on converting gma500 let's just move the code away so that new drivers don't end up accidentally using this. Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Reviewed-by: Alan Cox <alan@linux.intel.com> [danvet: Add __deprecated as requested by Alan. Also add a short FIXME comment and drop the EXPORT_SYMBOL which is no longer needed.] Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
* drm/dp: add a hw mutex around the transfer functions. (v2)Dave Airlie2014-06-051-7/+14
| | | | | | | | | This should avoid races between connector probing and HPD irqs in the future, currently mode_config.mutex blocks this possibility. Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm/dp-helper: Deprecate old i2c-over-dp_aux heleprsDaniel Vetter2014-06-021-0/+4
| | | | | | | | | | | | Only gma500 is still using this, once that's converted we can kill all this code. If that conversion doesn't happen soonish I think we should just move this helper code into the gma500 driver itself to avoid abuse from new drivers. Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp: Fix typo in commentThierry Reding2014-04-291-1/+1
| | | | | | | | Replace an occurrence of "adapater" with "adapter". Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm/dp/i2c: Update comments about common i2c over dp assumptions (v3)Alex Deucher2014-04-081-1/+3
| | | | | | | | | | | | | | | | | If you are using the common dp over i2c functionality, it is asumed that the aux transfer function does not modify the any of the msg structure other than the reply field. Doing so breaks the logic in the common code. v2: update struct drm_dp_aux comments about assumptions v3 (chk): rebased on upstream changes Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Thierry Reding <treding@nvidia.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Christian König <christian.koenig@amd.com>
* drm/dp/i2c: send bare addresses to properly reset i2c connections (v4)Alex Deucher2014-04-081-19/+32
| | | | | | | | | | | | | | | | | | | | | | | | | We need bare address packets at the start and end of each i2c over aux transaction to properly reset the connection between transactions. This mirrors what the existing dp i2c over aux algo currently does. This fixes EDID fetches on certain monitors especially with dp bridges. v2: update as per Ville's comments - Set buffer to NULL for zero sized packets - abort the entre transaction if one of the messages fails v3: drop leftover debugging code v4: integrate Thierry's comments - add comments about address only transactions - switch back to i and j Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Jani Nikula <jani.nikula@intel.com> Cc: Thierry Reding <treding@nvidia.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Christian König <christian.koenig@amd.com>
* drm/dp_helper: don't return EPROTO for defers (v2)Dave Airlie2014-04-051-4/+4
| | | | | | | | | | | | | | If we get a msg.reply of REPLY_DEFER, we also get an err of 0 so we fail reads with 0 < size and return -EPROTO instead of trying again. v2: same fix in i2c code. Found writing MST support. Reviewed-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
* Merge tag 'drm-intel-next-2014-03-21' of ↵Dave Airlie2014-04-031-1/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://anongit.freedesktop.org/drm-intel into drm-next - Inherit/reuse firmwar framebuffers (for real this time) from Jesse, less flicker for fastbooting. - More flexible cloning for hdmi (Ville). - Some PPGTT fixes from Ben. - Ring init fixes from Naresh Kumar. - set_cache_level regression fixes for the vma conversion from Ville&Chris. - Conversion to the new dp aux helpers (Jani). - Unification of runtime pm with pc8 support from Paulo, prep work for runtime pm on other platforms than HSW. - Larger cursor sizes (Sagar Kamble). - Piles of improvements and fixes all over, as usual. * tag 'drm-intel-next-2014-03-21' of git://anongit.freedesktop.org/drm-intel: (75 commits) drm/i915: Include a note about the dangers of I915_READ64/I915_WRITE64 drm/i915/sdvo: fix questionable return value check drm/i915: Fix unsafe loop iteration over vma whilst unbinding them drm/i915: Enabling 128x128 and 256x256 ARGB Cursor Support drm/i915: Print how many objects are shared in per-process stats drm/i915: Per-process stats work better when evaluated per-process drm/i915: remove rps local variables drm/i915: Remove extraneous MMIO for RPS drm/i915: Rename and comment all the RPS *stuff* drm/i915: Store the HW min frequency as min_freq drm/i915: Fix coding style for RPS drm/i915: Reorganize the overclock code drm/i915: init pm.suspended earlier drm/i915: update the PC8 and runtime PM documentation drm/i915: rename __hsw_do_{en, dis}able_pc8 drm/i915: kill struct i915_package_c8 drm/i915: move pc8.irqs_disabled to pm.irqs_disabled drm/i915: remove dev_priv->pc8.enabled drm/i915: don't get/put PC8 when getting/putting power wells drm/i915: make intel_aux_display_runtime_get get runtime PM, not PC8 ... Conflicts: drivers/gpu/drm/i915/intel_display.c drivers/gpu/drm/i915/intel_dp.c
| * drm/dp: let drivers specify the name of the I2C-over-AUX adapterJani Nikula2014-03-181-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let the drivers specify the name of the I2C-over-AUX adapter to maintain backwards compatibility in the sysfs when converting to the new I2C-over-AUX helper infrastructure. The i915 driver currently uses DPDDC-A to DPDDC-D as names for the DP i2c adapters. These names show up in the i2c sysfs name attribute. We'd like to be able to maintain that when switching over to the new helpers. Due to i2c device and connector cleanup ordering issues we also recently made the drm device (instead of connector) the parent of the i2c adapters: commit 80f65de3c9b8101c1613fa82df500ba6a099a11c Author: Imre Deak <imre.deak@intel.com> Date: Tue Feb 11 17:12:49 2014 +0200 drm/i915: dp: fix order of dp aux i2c device cleanup With the name picked up from the adapter parent using dev_name(), it would be the same for all i2c adapters with the current I2C-over-AUX helpers. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Acked-by: Dave Airlie <airlied@redhat.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* | drm/dp: make aux retries less chattyAlex Deucher2014-03-251-2/+2
|/ | | | | | | | | Switch to debug only to avoid flooding the logs. This mirrors the behavior in some other drivers. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Acked-by: Christian König <christian.koenig@amd.com>
* drm/dp: Allow registering AUX channels as I2C bussesThierry Reding2014-02-261-7/+179
| | | | | | | | | | | | | | | | | | | | | | | Implements an I2C-over-AUX I2C adapter on top of the generic drm_dp_aux infrastructure. It extracts the retry logic from existing drivers, which should help in porting those drivers to this new helper. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com> --- Changes in v5: - move comments partially to to header file - keep MOT set between I2C messages - return -EPROTO on short reads Changes in v4: - fix typo "bitrate" -> "bit rate" Changes in v3: - add back DRM_DEBUG_KMS and DRM_ERROR messages - embed i2c_adapter within struct drm_dp_aux - fix typo in comment
* drm/dp: Add DisplayPort link helpersThierry Reding2014-02-261-0/+97
| | | | | | | | | | | | | | | | | | | | | | | | Add a helper to probe a DP link (read out the supported DPCD revision, maximum rate, link count and capabilities) as well as power up the DP link and configure it accordingly. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com> --- Changes in v5: - export helpers Changes in v4: - fix a couple of typos in comments as pointed out by Alex Deucher Changes in v3: - split into drm_dp_link_power_up() and drm_dp_link_configure() - do not change sink state for DPCD versions earlier than 1.1 - sleep for 1-2 ms after setting local sink to D0 state - read and write consecutive registers where possible - read DPCD revision when link is probed - remove duplicate kerneldoc
* drm/dp: Add drm_dp_dpcd_read_link_status()Thierry Reding2014-02-261-0/+16
| | | | | | | | | | The function reads the link status (6 bytes starting at offset 0x202) from the DPCD so that it can be conveniently passed to other DPCD helpers. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com>
* drm/dp: Add AUX channel infrastructureThierry Reding2014-02-261-0/+110
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a superset of the current i2c_dp_aux bus functionality and can be used to transfer native AUX in addition to I2C-over-AUX messages. Helpers are provided to read and write the DPCD, either blockwise or byte-wise. Many of the existing helpers for DisplayPort take a copy of a portion of the DPCD and operate on that, without a way to write data back to the DPCD (e.g. for configuration of the link). Subsequent patches will build upon this infrastructure to provide common functionality in a generic way. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Thierry Reding <treding@nvidia.com> --- Changes in v5: - move comments partially to struct drm_dp_aux_msg in header file - return -EPROTO on short reads in DPCD helpers Changes in v4: - fix a typo in a comment Changes in v3: - reorder drm_dp_dpcd_writeb() arguments to be more intuitive - return number of bytes transferred in drm_dp_dpcd_write() - factor out drm_dp_dpcd_access() - describe error codes
* drm/dp: constify DP DPCD helpersJani Nikula2013-10-011-8/+8
| | | | | | | | | None of the DP DPCD helpers need to modify the DPCD. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm/doc: add new dp helpers into drm DocBookDaniel Vetter2012-11-281-0/+21
| | | | | | | | | | | | | | I didn't bother with documenting the really trivial new "extract something from dpcd" helpers, but the i2c over aux ch is now documented a bit. v2: Clarify the comment for i2c_dp_aux_add_bus a bit. v3: Fix more spelling fail spotted by Laurent Pinchart. Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
* drm: extract dp link bw helpersDaniel Vetter2012-10-221-0/+28
| | | | | | Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: extract dp link train delay functions from radeonDaniel Vetter2012-10-221-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | This requires a few changes since that dpcd value is above the range currently cached by radeon. I've check the dp specs, and above 0xf there's a big gap and nothing that looks like we should cache it while a given device is plugged in. It's also the same value that i915.ko uses. Hence extend the various dpcd arrays in the radeon driver, use proper symbolic constants where applicable (one place overallocated the dpcd array to 25 bytes). Then also drop the rd_interval cache - radeon_dp_link_train_init re-reads the dpcd block, so the values we'll consume in train_cr and train_ce will always be fresh. To avoid needless diff-churn, #define the old size of dpcd as the new one and keep it around. v2: Alex Deucher noticed one place where I've forgotten to replace 8 with DP_RECEIVER_CAP_SIZE. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: extract helpers to compute new training values from sink requestDaniel Vetter2012-10-221-0/+27
| | | | | | | | | Safe for the minor difference that the intel versions get an offset into the link_status as an argument, both are the same again. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: dp helper: extract drm_dp_channel_eq_okDaniel Vetter2012-10-221-0/+50
| | | | | | | | radeon and intel use the exact same definition. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
* drm: rename drm_dp_i2c_helper.c to drm_dp_helper.cDaniel Vetter2012-10-221-0/+207
I want to move some dp link training helpers into this place, so in the future this won't be just about i2c any longer. Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Dave Airlie <airlied@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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