<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/drivers/gpu/drm/msm/dp, branch v5.17.9</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=v5.17.9</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=v5.17.9'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2022-05-12T10:32:36+00:00</updated>
<entry>
<title>drm/msm/dp: remove fail safe mode related code</title>
<updated>2022-05-12T10:32:36+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-04-26T21:12:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0a65740339baee85bc2ce042130b10b333085266'/>
<id>urn:sha1:0a65740339baee85bc2ce042130b10b333085266</id>
<content type='text'>
commit 3f65b1e2f424f44585bd701024a3bfd0b1e0ade2 upstream.

Current DP driver implementation has adding safe mode done at
dp_hpd_plug_handle() which is expected to be executed under event
thread context.

However there is possible circular locking happen (see blow stack trace)
after edp driver call dp_hpd_plug_handle() from dp_bridge_enable() which
is executed under drm_thread context.

After review all possibilities methods and as discussed on
https://patchwork.freedesktop.org/patch/483155/, supporting EDID
compliance tests in the driver is quite hacky. As seen with other
vendor drivers, supporting these will be much easier with IGT. Hence
removing all the related fail safe code for it so that no possibility
of circular lock will happen.
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Reviewed-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;

======================================================
 WARNING: possible circular locking dependency detected
 5.15.35-lockdep #6 Tainted: G        W
 ------------------------------------------------------
 frecon/429 is trying to acquire lock:
 ffffff808dc3c4e8 (&amp;dev-&gt;mode_config.mutex){+.+.}-{3:3}, at:
dp_panel_add_fail_safe_mode+0x4c/0xa0

 but task is already holding lock:
 ffffff808dc441e0 (&amp;kms-&gt;commit_lock[i]){+.+.}-{3:3}, at: lock_crtcs+0xb4/0x124

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -&gt; #3 (&amp;kms-&gt;commit_lock[i]){+.+.}-{3:3}:
        __mutex_lock_common+0x174/0x1a64
        mutex_lock_nested+0x98/0xac
        lock_crtcs+0xb4/0x124
        msm_atomic_commit_tail+0x330/0x748
        commit_tail+0x19c/0x278
        drm_atomic_helper_commit+0x1dc/0x1f0
        drm_atomic_commit+0xc0/0xd8
        drm_atomic_helper_set_config+0xb4/0x134
        drm_mode_setcrtc+0x688/0x1248
        drm_ioctl_kernel+0x1e4/0x338
        drm_ioctl+0x3a4/0x684
        __arm64_sys_ioctl+0x118/0x154
        invoke_syscall+0x78/0x224
        el0_svc_common+0x178/0x200
        do_el0_svc+0x94/0x13c
        el0_svc+0x5c/0xec
        el0t_64_sync_handler+0x78/0x108
        el0t_64_sync+0x1a4/0x1a8

 -&gt; #2 (crtc_ww_class_mutex){+.+.}-{3:3}:
        __mutex_lock_common+0x174/0x1a64
        ww_mutex_lock+0xb8/0x278
        modeset_lock+0x304/0x4ac
        drm_modeset_lock+0x4c/0x7c
        drmm_mode_config_init+0x4a8/0xc50
        msm_drm_init+0x274/0xac0
        msm_drm_bind+0x20/0x2c
        try_to_bring_up_master+0x3dc/0x470
        __component_add+0x18c/0x3c0
        component_add+0x1c/0x28
        dp_display_probe+0x954/0xa98
        platform_probe+0x124/0x15c
        really_probe+0x1b0/0x5f8
        __driver_probe_device+0x174/0x20c
        driver_probe_device+0x70/0x134
        __device_attach_driver+0x130/0x1d0
        bus_for_each_drv+0xfc/0x14c
        __device_attach+0x1bc/0x2bc
        device_initial_probe+0x1c/0x28
        bus_probe_device+0x94/0x178
        deferred_probe_work_func+0x1a4/0x1f0
        process_one_work+0x5d4/0x9dc
        worker_thread+0x898/0xccc
        kthread+0x2d4/0x3d4
        ret_from_fork+0x10/0x20

 -&gt; #1 (crtc_ww_class_acquire){+.+.}-{0:0}:
        ww_acquire_init+0x1c4/0x2c8
        drm_modeset_acquire_init+0x44/0xc8
        drm_helper_probe_single_connector_modes+0xb0/0x12dc
        drm_mode_getconnector+0x5dc/0xfe8
        drm_ioctl_kernel+0x1e4/0x338
        drm_ioctl+0x3a4/0x684
        __arm64_sys_ioctl+0x118/0x154
        invoke_syscall+0x78/0x224
        el0_svc_common+0x178/0x200
        do_el0_svc+0x94/0x13c
        el0_svc+0x5c/0xec
        el0t_64_sync_handler+0x78/0x108
        el0t_64_sync+0x1a4/0x1a8

 -&gt; #0 (&amp;dev-&gt;mode_config.mutex){+.+.}-{3:3}:
        __lock_acquire+0x2650/0x672c
        lock_acquire+0x1b4/0x4ac
        __mutex_lock_common+0x174/0x1a64
        mutex_lock_nested+0x98/0xac
        dp_panel_add_fail_safe_mode+0x4c/0xa0
        dp_hpd_plug_handle+0x1f0/0x280
        dp_bridge_enable+0x94/0x2b8
        drm_atomic_bridge_chain_enable+0x11c/0x168
        drm_atomic_helper_commit_modeset_enables+0x500/0x740
        msm_atomic_commit_tail+0x3e4/0x748
        commit_tail+0x19c/0x278
        drm_atomic_helper_commit+0x1dc/0x1f0
        drm_atomic_commit+0xc0/0xd8
        drm_atomic_helper_set_config+0xb4/0x134
        drm_mode_setcrtc+0x688/0x1248
        drm_ioctl_kernel+0x1e4/0x338
        drm_ioctl+0x3a4/0x684
        __arm64_sys_ioctl+0x118/0x154
        invoke_syscall+0x78/0x224
        el0_svc_common+0x178/0x200
        do_el0_svc+0x94/0x13c
        el0_svc+0x5c/0xec
        el0t_64_sync_handler+0x78/0x108
        el0t_64_sync+0x1a4/0x1a8

Changes in v2:
-- re text commit title
-- remove all fail safe mode

Changes in v3:
-- remove dp_panel_add_fail_safe_mode() from dp_panel.h
-- add Fixes

Changes in v5:
--  to=dianders@chromium.org

Changes in v6:
--  fix Fixes commit ID

Fixes: 8b2c181e3dcf ("drm/msm/dp: add fail safe mode outside of event_mutex context")
Reported-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Link: https://lore.kernel.org/r/1651007534-31842-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: add fail safe mode outside of event_mutex context</title>
<updated>2022-04-20T07:36:15+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-04-08T21:04:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=cc4826f7b496cb0c66bed423778bf4fa3a80dcfd'/>
<id>urn:sha1:cc4826f7b496cb0c66bed423778bf4fa3a80dcfd</id>
<content type='text'>
[ Upstream commit 8b2c181e3dcf7562445af6702ee94aaedcbe13c8 ]

There is possible circular locking dependency detected on event_mutex
(see below logs). This is due to set fail safe mode is done at
dp_panel_read_sink_caps() within event_mutex scope. To break this
possible circular locking, this patch move setting fail safe mode
out of event_mutex scope.

[   23.958078] ======================================================
[   23.964430] WARNING: possible circular locking dependency detected
[   23.970777] 5.17.0-rc2-lockdep-00088-g05241de1f69e #148 Not tainted
[   23.977219] ------------------------------------------------------
[   23.983570] DrmThread/1574 is trying to acquire lock:
[   23.988763] ffffff808423aab0 (&amp;dp-&gt;event_mutex){+.+.}-{3:3}, at: msm_dp_displ                                                                             ay_enable+0x58/0x164
[   23.997895]
[   23.997895] but task is already holding lock:
[   24.003895] ffffff808420b280 (&amp;kms-&gt;commit_lock[i]/1){+.+.}-{3:3}, at: lock_c                                                                             rtcs+0x80/0x8c
[   24.012495]
[   24.012495] which lock already depends on the new lock.
[   24.012495]
[   24.020886]
[   24.020886] the existing dependency chain (in reverse order) is:
[   24.028570]
[   24.028570] -&gt; #5 (&amp;kms-&gt;commit_lock[i]/1){+.+.}-{3:3}:
[   24.035472]        __mutex_lock+0xc8/0x384
[   24.039695]        mutex_lock_nested+0x54/0x74
[   24.044272]        lock_crtcs+0x80/0x8c
[   24.048222]        msm_atomic_commit_tail+0x1e8/0x3d0
[   24.053413]        commit_tail+0x7c/0xfc
[   24.057452]        drm_atomic_helper_commit+0x158/0x15c
[   24.062826]        drm_atomic_commit+0x60/0x74
[   24.067403]        drm_mode_atomic_ioctl+0x6b0/0x908
[   24.072508]        drm_ioctl_kernel+0xe8/0x168
[   24.077086]        drm_ioctl+0x320/0x370
[   24.081123]        drm_compat_ioctl+0x40/0xdc
[   24.085602]        __arm64_compat_sys_ioctl+0xe0/0x150
[   24.090895]        invoke_syscall+0x80/0x114
[   24.095294]        el0_svc_common.constprop.3+0xc4/0xf8
[   24.100668]        do_el0_svc_compat+0x2c/0x54
[   24.105242]        el0_svc_compat+0x4c/0xe4
[   24.109548]        el0t_32_sync_handler+0xc4/0xf4
[   24.114381]        el0t_32_sync+0x178
[   24.118688]
[   24.118688] -&gt; #4 (&amp;kms-&gt;commit_lock[i]){+.+.}-{3:3}:
[   24.125408]        __mutex_lock+0xc8/0x384
[   24.129628]        mutex_lock_nested+0x54/0x74
[   24.134204]        lock_crtcs+0x80/0x8c
[   24.138155]        msm_atomic_commit_tail+0x1e8/0x3d0
[   24.143345]        commit_tail+0x7c/0xfc
[   24.147382]        drm_atomic_helper_commit+0x158/0x15c
[   24.152755]        drm_atomic_commit+0x60/0x74
[   24.157323]        drm_atomic_helper_set_config+0x68/0x90
[   24.162869]        drm_mode_setcrtc+0x394/0x648
[   24.167535]        drm_ioctl_kernel+0xe8/0x168
[   24.172102]        drm_ioctl+0x320/0x370
[   24.176135]        drm_compat_ioctl+0x40/0xdc
[   24.180621]        __arm64_compat_sys_ioctl+0xe0/0x150
[   24.185904]        invoke_syscall+0x80/0x114
[   24.190302]        el0_svc_common.constprop.3+0xc4/0xf8
[   24.195673]        do_el0_svc_compat+0x2c/0x54
[   24.200241]        el0_svc_compat+0x4c/0xe4
[   24.204544]        el0t_32_sync_handler+0xc4/0xf4
[   24.209378]        el0t_32_sync+0x174/0x178
[   24.213680] -&gt; #3 (crtc_ww_class_mutex){+.+.}-{3:3}:
[   24.220308]        __ww_mutex_lock.constprop.20+0xe8/0x878
[   24.225951]        ww_mutex_lock+0x60/0xd0
[   24.230166]        modeset_lock+0x190/0x19c
[   24.234467]        drm_modeset_lock+0x34/0x54
[   24.238953]        drmm_mode_config_init+0x550/0x764
[   24.244065]        msm_drm_bind+0x170/0x59c
[   24.248374]        try_to_bring_up_master+0x244/0x294
[   24.253572]        __component_add+0xf4/0x14c
[   24.258057]        component_add+0x2c/0x38
[   24.262273]        dsi_dev_attach+0x2c/0x38
[   24.266575]        dsi_host_attach+0xc4/0x120
[   24.271060]        mipi_dsi_attach+0x34/0x48
[   24.275456]        devm_mipi_dsi_attach+0x28/0x68
[   24.280298]        ti_sn_bridge_probe+0x2b4/0x2dc
[   24.285137]        auxiliary_bus_probe+0x78/0x90
[   24.289893]        really_probe+0x1e4/0x3d8
[   24.294194]        __driver_probe_device+0x14c/0x164
[   24.299298]        driver_probe_device+0x54/0xf8
[   24.304043]        __device_attach_driver+0xb4/0x118
[   24.309145]        bus_for_each_drv+0xb0/0xd4
[   24.313628]        __device_attach+0xcc/0x158
[   24.318112]        device_initial_probe+0x24/0x30
[   24.322954]        bus_probe_device+0x38/0x9c
[   24.327439]        deferred_probe_work_func+0xd4/0xf0
[   24.332628]        process_one_work+0x2f0/0x498
[   24.337289]        process_scheduled_works+0x44/0x48
[   24.342391]        worker_thread+0x1e4/0x26c
[   24.346788]        kthread+0xe4/0xf4
[   24.350470]        ret_from_fork+0x10/0x20
[   24.354683]
[   24.354683]
[   24.354683] -&gt; #2 (crtc_ww_class_acquire){+.+.}-{0:0}:
[   24.361489]        drm_modeset_acquire_init+0xe4/0x138
[   24.366777]        drm_helper_probe_detect_ctx+0x44/0x114
[   24.372327]        check_connector_changed+0xbc/0x198
[   24.377517]        drm_helper_hpd_irq_event+0xcc/0x11c
[   24.382804]        dsi_hpd_worker+0x24/0x30
[   24.387104]        process_one_work+0x2f0/0x498
[   24.391762]        worker_thread+0x1d0/0x26c
[   24.396158]        kthread+0xe4/0xf4
[   24.399840]        ret_from_fork+0x10/0x20
[   24.404053]
[   24.404053] -&gt; #1 (&amp;dev-&gt;mode_config.mutex){+.+.}-{3:3}:
[   24.411032]        __mutex_lock+0xc8/0x384
[   24.415247]        mutex_lock_nested+0x54/0x74
[   24.419819]        dp_panel_read_sink_caps+0x23c/0x26c
[   24.425108]        dp_display_process_hpd_high+0x34/0xd4
[   24.430570]        dp_display_usbpd_configure_cb+0x30/0x3c
[   24.436205]        hpd_event_thread+0x2ac/0x550
[   24.440864]        kthread+0xe4/0xf4
[   24.444544]        ret_from_fork+0x10/0x20
[   24.448757]
[   24.448757] -&gt; #0 (&amp;dp-&gt;event_mutex){+.+.}-{3:3}:
[   24.455116]        __lock_acquire+0xe2c/0x10d8
[   24.459690]        lock_acquire+0x1ac/0x2d0
[   24.463988]        __mutex_lock+0xc8/0x384
[   24.468201]        mutex_lock_nested+0x54/0x74
[   24.472773]        msm_dp_display_enable+0x58/0x164
[   24.477789]        dp_bridge_enable+0x24/0x30
[   24.482273]        drm_atomic_bridge_chain_enable+0x78/0x9c
[   24.488006]        drm_atomic_helper_commit_modeset_enables+0x1bc/0x244
[   24.494801]        msm_atomic_commit_tail+0x248/0x3d0
[   24.499992]        commit_tail+0x7c/0xfc
[   24.504031]        drm_atomic_helper_commit+0x158/0x15c
[   24.509404]        drm_atomic_commit+0x60/0x74
[   24.513976]        drm_mode_atomic_ioctl+0x6b0/0x908
[   24.519079]        drm_ioctl_kernel+0xe8/0x168
[   24.523650]        drm_ioctl+0x320/0x370
[   24.527689]        drm_compat_ioctl+0x40/0xdc
[   24.532175]        __arm64_compat_sys_ioctl+0xe0/0x150
[   24.537463]        invoke_syscall+0x80/0x114
[   24.541861]        el0_svc_common.constprop.3+0xc4/0xf8
[   24.547235]        do_el0_svc_compat+0x2c/0x54
[   24.551806]        el0_svc_compat+0x4c/0xe4
[   24.556106]        el0t_32_sync_handler+0xc4/0xf4
[   24.560948]        el0t_32_sync+0x174/0x178

Changes in v2:
-- add circular lockiing trace

Fixes: d4aca422539c ("drm/msm/dp:  always add fail-safe mode into connector mode list")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Patchwork: https://patchwork.freedesktop.org/patch/481396/
Link: https://lore.kernel.org/r/1649451894-554-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: fix panel bridge attachment</title>
<updated>2022-04-08T11:58:09+00:00</updated>
<author>
<name>Dmitry Baryshkov</name>
<email>dmitry.baryshkov@linaro.org</email>
</author>
<published>2022-02-11T22:40:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=22efb1063406387de09d45f4dbe24add583d2557'/>
<id>urn:sha1:22efb1063406387de09d45f4dbe24add583d2557</id>
<content type='text'>
[ Upstream commit 4d793a02c4967ab14d4ae5e86a51ee02ed78921a ]

In commit 8a3b4c17f863 ("drm/msm/dp: employ bridge mechanism for display
enable and disable") the DP driver received a drm_bridge instance, which
is always attached to the encoder as a root bridge. However it conflicts
with the panel_bridge support for eDP panels. The panel bridge attaches
to the encoder before the "dp" bridge (DP driver's drm_bridge instance
created in msm_dp_bridge_init()) has a chance to do so. Change
panel bridge attachment to come after the "dp" bridge attachment (and to
use it as a previous bridge).

Fixes: 8a3b4c17f863 ("drm/msm/dp: employ bridge mechanism for display enable and disable")
Cc: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Tested-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/20220211224006.1797846-2-dmitry.baryshkov@linaro.org
[db: fixed commit message according to Stephen's suggestions]
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: always add fail-safe mode into connector mode list</title>
<updated>2022-04-08T11:58:09+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-24T23:17:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0340c56a2bfb68af39eb0c32a49cf010a68ed3f0'/>
<id>urn:sha1:0340c56a2bfb68af39eb0c32a49cf010a68ed3f0</id>
<content type='text'>
[ Upstream commit d4aca422539c441a7f3fec749287b36de37d9b6b ]

Some of DP link compliant test expects to return fail-safe mode
if prefer detailed timing mode can not be supported by mainlink's
lane and rate after link training. Therefore add fail-safe mode
into connector mode list as backup mode. This patch fixes test
case 4.2.2.1.

Changes in v2:
-- add Fixes text string

Fixes: 4b85d405cfe9 ( "drm/msm/dp: reduce link rate if failed at link training 1")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1643066274-25814-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: stop link training after link training 2 failed</title>
<updated>2022-04-08T11:58:09+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-18T18:47:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=0cba8ad286c64f05a06ad844cf25598daa925783'/>
<id>urn:sha1:0cba8ad286c64f05a06ad844cf25598daa925783</id>
<content type='text'>
[ Upstream commit 9051d629dbf7a998a40f7eac65a9512b01bc3bb8 ]

Each DP link training contains link training 1 followed by link
training 2.  There is maximum of 5 retries of DP link training
before declared link training failed. It is required to stop link
training at end of link training 2 if it is failed so that next
link training 1 can start freshly. This patch fixes link compliance
test  case 4.3.1.13 (Source Device Link Training EQ Fallback Test).

Changes in v10:
--  group into one series

Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read

Fixes: 2e0adc765d88 ("drm/msm/dp: do not end dp link training until video is ready")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1642531648-8448-5-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: populate connector of struct dp_panel</title>
<updated>2022-04-08T11:58:08+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-18T18:47:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=104074ebc0c3f358dd1ee944fbcde92c6e5a21dd'/>
<id>urn:sha1:104074ebc0c3f358dd1ee944fbcde92c6e5a21dd</id>
<content type='text'>
[ Upstream commit 5e602f5156910c7b19661699896cb6e3fb94fab9 ]

DP CTS test case 4.2.2.6 has valid edid with bad checksum on purpose
and expect DP source return correct checksum. During drm edid read,
correct edid checksum is calculated and stored at
connector::real_edid_checksum.

The problem is struct dp_panel::connector never be assigned, instead the
connector is stored in struct msm_dp::connector. When we run compliance
testing test case 4.2.2.6 dp_panel_handle_sink_request() won't have a valid
edid set in struct dp_panel::edid so we'll try to use the connectors
real_edid_checksum and hit a NULL pointer dereference error because the
connector pointer is never assigned.

Changes in V2:
-- populate panel connector at msm_dp_modeset_init() instead of at dp_panel_read_sink_caps()

Changes in V3:
-- remove unhelpful kernel crash trace commit text
-- remove renaming dp_display parameter to dp

Changes in V4:
-- add more details to commit text

Changes in v10:
--  group into one series

Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read

Fixes: 7948fe12d47 ("drm/msm/dp: return correct edid checksum after corrupted edid checksum read")
Signee-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;

Reviewed-by: Bjorn Andersson &lt;bjorn.andersson@linaro.org&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1642531648-8448-3-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: do not initialize phy until plugin interrupt received</title>
<updated>2022-04-08T11:58:08+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2022-01-18T18:47:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=3795c424ffcbb101bfefe78ca25a96558adedcb6'/>
<id>urn:sha1:3795c424ffcbb101bfefe78ca25a96558adedcb6</id>
<content type='text'>
[ Upstream commit 989ebe7bc4463002c210db0010c8475797a9098f ]

Current DP drivers have regulators, clocks, irq and phy are grouped
together within a function and executed not in a symmetric manner.
This increase difficulty of code maintenance and limited code scalability.
This patch divides the driver life cycle of operation into four states,
resume (including booting up), dongle plugin, dongle unplugged and suspend.
Regulators, core clocks and irq are grouped together and enabled at resume
(or booting up) so that the DP controller is armed and ready to receive HPD
plugin interrupts. HPD plugin interrupt is generated when a dongle plugs
into DUT (device under test). Once HPD plugin interrupt is received, DP
controller will initialize phy so that dpcd read/write will function and
following link training can be proceeded successfully. DP phy will be
disabled after main link is teared down at end of unplugged HPD interrupt
handle triggered by dongle unplugged out of DUT. Finally regulators, code
clocks and irq are disabled at corresponding suspension.

Changes in V2:
-- removed unnecessary dp_ctrl NULL check
-- removed unnecessary phy init_count and power_count DRM_DEBUG_DP logs
-- remove flip parameter out of dp_ctrl_irq_enable()
-- add fixes tag

Changes in V3:
-- call dp_display_host_phy_init() instead of dp_ctrl_phy_init() at
        dp_display_host_init() for eDP

Changes in V4:
-- rewording commit text to match this commit changes

Changes in V5:
-- rebase on top of msm-next branch

Changes in V6:
-- delete flip variable

Changes in V7:
-- dp_ctrl_irq_enable/disabe() merged into dp_ctrl_reset_irq_ctrl()

Changes in V8:
-- add more detail comment regrading dp phy at dp_display_host_init()

Changes in V9:
-- remove set phy_initialized to false when -ECONNRESET detected

Changes in v10:
--  group into one series

Changes in v11:
-- drop drm/msm/dp: dp_link_parse_sink_count() return immediately
	if aux read

Changes in v12:
-- move dp_display_host_phy_exit() after dp_display_host_deinit()

Changes in v13:
-- do not execute phy_init until plugged_in interrupt for edp, same as DP.

Changes in v14:
-- remove redundant dp-&gt;core_initialized = false form dp_pm_suspend.

Changes in v15:
-- remove core_initialized flag check at both host_init and host_deinit

Changes in v16:
-- remove dp_display_host_phy_exit core_initialized=false at dp_pm_suspend

Changes in v17:
-- remove core_initialized checking before execute attention_cb()

Changes in v18:
-- remove core_initialized checking at dp_pm_suspend

Fixes: 8ede2ecc3e5e ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets")
Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1642531648-8448-2-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: remove unneeded variable</title>
<updated>2021-12-16T17:51:25+00:00</updated>
<author>
<name>Changcheng Deng</name>
<email>deng.changcheng@zte.com.cn</email>
</author>
<published>2021-12-15T08:55:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=7620bdfb250247388a501e5e9ff8185c2191e453'/>
<id>urn:sha1:7620bdfb250247388a501e5e9ff8185c2191e453</id>
<content type='text'>
Remove unneeded variable used to store return value.

Reported-by: Zeal Robot &lt;zealci@zte.com.cn&gt;
Signed-off-by: Changcheng Deng &lt;deng.changcheng@zte.com.cn&gt;
Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/20211215085554.444351-1-deng.changcheng@zte.com.cn
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: Fix double free on error in msm_dp_bridge_init()</title>
<updated>2021-12-15T23:28:40+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2021-12-15T11:49:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=48d0cf4a7cf2d5447f997e232c6378bb02434655'/>
<id>urn:sha1:48d0cf4a7cf2d5447f997e232c6378bb02434655</id>
<content type='text'>
The "dp_bridge" pointer is allocated with devm_kzalloc() so it will be
freed automatically.  Kfreeing it here will only lead to a double free.

Fixes: 8a3b4c17f863 ("drm/msm/dp: employ bridge mechanism for display enable and disable")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Reviewed-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Link: https://lore.kernel.org/r/20211215114900.GD14552@kili
Signed-off-by: Dmitry Baryshkov &lt;dmitry.baryshkov@linaro.org&gt;
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
</content>
</entry>
<entry>
<title>drm/msm/dp: dp_link_parse_sink_count() return immediately if aux read failed</title>
<updated>2021-12-08T18:34:55+00:00</updated>
<author>
<name>Kuogee Hsieh</name>
<email>quic_khsieh@quicinc.com</email>
</author>
<published>2021-12-08T17:41:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f61550b3864b9578527c28cf9c465316ac1566e1'/>
<id>urn:sha1:f61550b3864b9578527c28cf9c465316ac1566e1</id>
<content type='text'>
Add checking aux read/write status at both dp_link_parse_sink_count()
and dp_link_parse_sink_status_filed() to avoid long timeout delay if
dp aux read/write failed at timeout due to cable unplugged.

Changes in V4:
-- split this patch as stand alone patch

Changes in v5:
-- rebase on msm-next branch

Signed-off-by: Kuogee Hsieh &lt;quic_khsieh@quicinc.com&gt;

Reviewed-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Tested-by: Stephen Boyd &lt;swboyd@chromium.org&gt;
Link: https://lore.kernel.org/r/1638985262-2072-1-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Rob Clark &lt;robdclark@chromium.org&gt;
</content>
</entry>
</feed>
