[PATCH 001/001] drivers/gpu/radeon: NULL pointer deference workaround
Mark Fortescue
mark at thurning-instruments.co.uk
Fri Sep 9 13:32:50 UTC 2016
On 09/09/16 13:20, Deucher, Alexander wrote:
>> -----Original Message-----
>> From: Koenig, Christian
>> Sent: Friday, September 09, 2016 4:16 AM
>> To: Mark Fortescue; Koenig, Christian; David Airlie
>> Cc: Deucher, Alexander; linux-kernel at vger.kernel.org; dri-
>> devel at lists.freedesktop.org
>> Subject: Re: [PATCH 001/001] drivers/gpu/radeon: NULL pointer deference
>> workaround
>>
>>>> On this motherboard, DP-1 is a single channel 18bit LVDS LCD panel
>>>> interface and DP-2 is a DVI interface (which I can connect to my
>>>> monitor if testing this is useful). There are no displayport connectors.
>>>
>>> Yeah, but from the driver point of view there are only DP connectors on
>>> the chip. The LVDS and DVI are probably realized with external DP to
>>> whatever converter ICs.
>>>
>>>
>>> That would explain why some similar boards have 24bit LVDS and others
>>> only 18bit LVDS.
>>
>> It could be that this is actually a configuration we don't support yet
>> with radeon and/or the display stack.
>>
>> E.g. that the connector only uses the displayport LVDS lanes, but not
>> actual the displayport protocol to train those lanes.
>>
>> Instead it rather expects a fixed training which is configured somewhere
>> in the BIOS.
>>
>> Anyway Alex needs to take a look, he knows displayport much better than
>> I do (and hates it passionately :).
>
> Generally these sorts of setups are supported by exposing an LVDS or eDP connector rather than a regular DP. In the case of LVDS and eDP, we have code to fallback to a hardcoded EDID in the vbios if DDC is not available. I'll take a closer look when I'm back.
>
> Alex
Thanks Alex,
I look forward to hearing from you when you have finished recovering
from your holiday and the associated work backlog :).
I raised a bug (https://bugs.freedesktop.org/show_bug.cgi?id=97637) -
probably on the wrong component but fixing that should be easy.
It has a more complete copy of the Opps.
Regards
Mark.
>
>>
>> Cheers,
>> Christian.
>>
>> Am 08.09.2016 um 13:18 schrieb Mark Fortescue:
>>> On 08/09/16 11:25, Christian König wrote:
>>>> Am 08.09.2016 um 11:09 schrieb Mark Fortescue:
>>>>> Hi Christian,
>>>>>
>>>>> Thank you for the feedback.
>>>>>
>>>>> On 08/09/16 08:14, Christian König wrote:
>>>>>> Am 07.09.2016 um 19:38 schrieb Mark Fortescue:
>>>>>>>
>>>>>>> On an LV-683 (AMD Dual-core G-T56N) Mini-ITX board, I get a Kernel
>>>>>>> Oops because Connector 0 (LCD Panel interface) does not have DDC.
>>>>>>
>>>>>> I'm not an expert on this, but that is really odd cause even LCD
>>>>>> Panels
>>>>>> should have a DDC interface.
>>>>>>
>>>>>>>
>>>>>>> Ubuntu 16.04 LTS Kernel (4.4 series):
>>>>>>>
>>>>>>> ...
>>>>>>> [ 8.262990] [drm] ib test on ring 5 succeeded
>>>>>>> [ 8.288897] [drm] Radeon Display Connectors
>>>>>>> [ 8.293175] [drm] Connector 0:
>>>>>>> [ 8.296252] [drm] DP-1
>>>>>>
>>>>>> Especially since the BIOS claims that this is a displayport connector
>>>>>> and there is no physical way to have a DP without an DDC as far as I
>>>>>> know.
>>>>>>
>>>>>> Please open a bug report on FDO and attach you BIOS image.
>>>>>
>>>>> FDO ? I am not familiar with this. Please can you enlighten me.
>>>>>
>>>>
>>>> See here: http://bugs.freedesktop.org/
>>>>
>>>>> I do not have a BIOS image so will need some assistance in
>>>>> understanding what is required here and how I extract the BIOS
>>>>> information you are after.
>>>>>
>>>>
>>>> Sorry my fault. Mullins is an APU, so you don't have a dedicated video
>>>> BIOS. As usually I didn't got enough sleep :) But please open up a bug
>>>> report anyway.
>>>
>>> Know the problem of being awake too long :). I will raise a bug.
>>>
>>>>
>>>>> On this motherboard, DP-1 is a single channel 18bit LVDS LCD panel
>>>>> interface and DP-2 is a DVI interface (which I can connect to my
>>>>> monitor if testing this is useful). There are no displayport
>>>>> connectors.
>>>>
>>>> Yeah, but from the driver point of view there are only DP connectors on
>>>> the chip. The LVDS and DVI are probably realized with external DP to
>>>> whatever converter ICs.
>>>>
>>>
>>> That would explain why some similar boards have 24bit LVDS and others
>>> only 18bit LVDS.
>>>
>>>>>
>>>>> On industrial motherboards, I have noticed that it is not uncommon to
>>>>> hard code the information for the LCD panel into the BIOS so no DDC is
>>>>> required. In this case, there is no LCD panel connected to the
>>>>> interface anyway.
>>>>>
>>>>
>>>> That is correct and as far as I know well supported by Radeon, but the
>>>> crux is there should still be a DDC channel even if there isn't anything
>>>> attached to it.
>>>>
>>>> See with displayport you got four LVDS channels to submit the actual
>>>> picture and an AUX channel to configure and query the device. The DDC is
>>>> just represented as certain packets over the AUX channel.
>>>>
>>>> If the AUX channel doesn't work or isn't connect then the link training
>>>> wouldn't be possible as well and so you wouldn't be able to get any
>>>> picture on the LVDS.
>>>>
>>>
>>> Interesting.
>>>
>>>>> See http://www.commell.com.tw/product/SBC/LV-683.HTM for more
>>>>> information on the board. Looking at the web site, there is a BIOS
>>>>> image available form Commell if that is of use.
>>>>
>>>> Alex clearly needs to take a look on this. I think for the time being
>>>> you could hack together a patch which just ignores DP connectors during
>>>> probing if they don't have an associated DDC instead of changing the
>>>> code everywhere the DDC object is required.
>>>>
>>>
>>> I will try to find the time to look at this in more detail. GPU/DRM is
>>> not something I have done any real work on in the past so I do not
>>> know how it all fits together. The overkill on the code changes is the
>>> result, as that way I don't need to understand where and why the
>>> helper function (radeon_dp_getsinktype) gets called or what other code
>>> paths can be executed that could fail.
>>>
>>> I will wait for Alex to have a think about it and respond before I do
>>> any more - that way I can finish the work I am paid to do first :).
>>>
>>>> Regards,
>>>> Christian.
>>>>
>>> Regards
>>> Mark.
>>>>>
>>>>>>
>>>>>> Alex can probably take a look when he's back from vacation.
>>>>>>
>>>>>> Regards,
>>>>>> Christian.
>>>>>>
>>>>>>> [ 8.298791] [drm] Encoders:
>>>>>>> [ 8.301770] [drm] DFP1: INTERNAL_UNIPHY
>>>>>>> [ 8.305973] [drm] Connector 1:
>>>>>>> [ 8.309043] [drm] DP-2
>>>>>>> [ 8.311598] [drm] HPD2
>>>>>>> [ 8.314169] [drm] DDC: 0x6440 0x6440 0x6444 0x6444 0x6448 0x6448
>>>>>>> 0x644c 0x644c
>>>>>>> [ 8.321609] [drm] Encoders:
>>>>>>> [ 8.324589] [drm] DFP2: INTERNAL_UNIPHY
>>>>>>> [ 8.328793] [drm] Connector 2:
>>>>>>> [ 8.331856] [drm] VGA-1
>>>>>>> [ 8.342947] [drm] DDC: 0x64d8 0x64d8 0x64dc 0x64dc 0x64e0 0x64e0
>>>>>>> 0x64e4 0x64e4
>>>>>>> [ 8.350341] [drm] Encoders:
>>>>>>> [ 8.353310] [drm] CRT1: INTERNAL_KLDSCP_DAC1
>>>>>>> [ 8.358195] BUG: unable to handle kernel NULL pointer dereference at
>>>>>>> 0000000000000409
>>>>>>> [ 8.409733] [<ffffffffc02024da>] radeon_dp_getsinktype+0x1a/0x30
>>>>>>> [radeon]
>>>>>>> [ 8.416805] PGD 0
>>>>>>> [ 8.418841] Oops: 0000 [#1] SMP
>>>>>>> ...
>>>>>>>
>>>>>>> This patch prevents Kernel failures due to a connector not having a
>>>>>>> DDC interface by changing the code so that ddc_bus is always checked
>>>>>>> before use.
>>>>>>> The problem was first identified using the uBuntu MATE 14.04 LTS
>>>>>>> (3.16
>>>>>>> series kernels) but not dealt with at that time. On attempting to
>>>>>>> install uBuntu MATE 16.04 LTS (4.4 series kernels), it became clear
>>>>>>> that using various workarounds to allow the issue to be ignored were
>>>>>>> not viable so more effort was put in to sorting the issue
>>>>>>> resulting in
>>>>>>> this patch. See https://bugs.launchpad.net/bugs/1587885 for more
>>>>>>> details.
>>>>>>>
>>>>>>> Signed-off-by: Mark Fortescue <mark at thurning-instruments.co.uk>
>>>>>>> Tested-by: Mark Fortescue <mark at thurning-instruments.co.uk>
>>>>>>>
>>>>>>> ---
>>>>>>>
>>>>>>> Looks like Thunderbird may have made a mess of the patch when
>> pasting
>>>>>>> the contents into the mail message - my alternate mail client (pine)
>>>>>>> also has strict line length handling and trashes non-MIME encoded
>>>>>>> patches.
>>>>>>>
>>>>>>> This may not be the correct approach to solving the issue but it is
>>>>>>> clean in that it ensures that ddc_bus is never used when NULL
>>>>>>> regardless of how the code ended up at the point of use.
>>>>>>>
>>>>>>> If it helps with back porting, I have patches for the uBuntu 14.04
>>>>>>> LTS
>>>>>>> [3.13 series], uBuntu MATE 14.04 LTS [3.16 series] and uBuntu 16.04
>>>>>>> LTS [4.4 series] kernels.
>>>>>>>
>>>>>>> Test Hardware:
>>>>>>> Commell LV-683 Mini-ITX with onboard AMD Dual-core G-T56N
>>>>>>> 4G Ram, 2x1TB Disk, HANNS-G HC194D 1280x1024 LCD (VGA).
>>>>>>> 4.8.0-rc5 with patch boots without error.
>>>>>>>
>>>>>>> drivers/gpu/drm/radeon/atombios_dp.c | 60
>>>>>>> ++++++++++++-------
>>>>>>> drivers/gpu/drm/radeon/radeon_connectors.c | 46 +++++++-------
>>>>>>> drivers/gpu/drm/radeon/radeon_dp_mst.c | 9 ++
>>>>>>> drivers/gpu/drm/radeon/radeon_i2c.c | 3
>>>>>>> 4 files changed, 73 insertions(+), 45 deletions(-)
>>>>>>>
>>>>>>> Patch:
>>>>>>> diff --git a/drivers/gpu/drm/radeon/atombios_dp.c
>>>>>>> b/drivers/gpu/drm/radeon/atombios_dp.c
>>>>>>> index cead089a..98b3c0e 100644
>>>>>>> --- a/drivers/gpu/drm/radeon/atombios_dp.c
>>>>>>> +++ b/drivers/gpu/drm/radeon/atombios_dp.c
>>>>>>> @@ -232,6 +232,9 @@ void radeon_dp_aux_init(struct
>> radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> struct radeon_device *rdev = dev->dev_private;
>>>>>>> int ret;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return;
>>>>>>> +
>>>>>>> radeon_connector->ddc_bus->rec.hpd = radeon_connector-
>>> hpd.hpd;
>>>>>>> radeon_connector->ddc_bus->aux.dev =
>>>>>>> radeon_connector->base.kdev;
>>>>>>> if (ASIC_IS_DCE5(rdev)) {
>>>>>>> @@ -364,6 +367,9 @@ u8 radeon_dp_getsinktype(struct
>> radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> struct drm_device *dev = radeon_connector->base.dev;
>>>>>>> struct radeon_device *rdev = dev->dev_private;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return 0;
>>>>>>> +
>>>>>>> return radeon_dp_encoder_service(rdev,
>>>>>>> ATOM_DP_ACTION_GET_SINK_TYPE, 0,
>>>>>>> radeon_connector->ddc_bus->rec.i2c_id, 0);
>>>>>>> }
>>>>>>> @@ -376,6 +382,9 @@ static void radeon_dp_probe_oui(struct
>>>>>>> radeon_connector *radeon_connector)
>>>>>>> if (!(dig_connector->dpcd[DP_DOWN_STREAM_PORT_COUNT] &
>>>>>>> DP_OUI_SUPPORT))
>>>>>>> return;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return;
>>>>>>> +
>>>>>>> if (drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_SINK_OUI, buf, 3) == 3)
>>>>>>> DRM_DEBUG_KMS("Sink OUI: %02hx%02hx%02hx\n",
>>>>>>> buf[0], buf[1], buf[2]);
>>>>>>> @@ -391,6 +400,9 @@ bool radeon_dp_getdpcd(struct
>> radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> u8 msg[DP_DPCD_SIZE];
>>>>>>> int ret, i;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return false;
>>>>>>> +
>>>>>>> for (i = 0; i < 7; i++) {
>>>>>>> ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_DPCD_REV, msg,
>>>>>>> DP_DPCD_SIZE);
>>>>>>> @@ -428,24 +440,26 @@ int radeon_dp_get_panel_mode(struct
>> drm_encoder
>>>>>>> *encoder,
>>>>>>>
>>>>>>> dig_connector = radeon_connector->con_priv;
>>>>>>>
>>>>>>> - if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
>>>>>>> - /* DP bridge chips */
>>>>>>> - if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> - DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
>>>>>>> - if (tmp & 1)
>>>>>>> - panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
>>>>>>> - else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
>>>>>>> - (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
>>>>>>> - panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
>>>>>>> - else
>>>>>>> - panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
>>>>>>> - }
>>>>>>> - } else if (connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_eDP) {
>>>>>>> - /* eDP */
>>>>>>> - if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> - DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
>>>>>>> - if (tmp & 1)
>>>>>>> - panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
>>>>>>> + if (radeon_connector->ddc_bus) {
>>>>>>> + if (dp_bridge != ENCODER_OBJECT_ID_NONE) {
>>>>>>> + /* DP bridge chips */
>>>>>>> + if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> + DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
>>>>>>> + if (tmp & 1)
>>>>>>> + panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
>>>>>>> + else if ((dp_bridge == ENCODER_OBJECT_ID_NUTMEG) ||
>>>>>>> + (dp_bridge == ENCODER_OBJECT_ID_TRAVIS))
>>>>>>> + panel_mode = DP_PANEL_MODE_INTERNAL_DP1_MODE;
>>>>>>> + else
>>>>>>> + panel_mode = DP_PANEL_MODE_EXTERNAL_DP_MODE;
>>>>>>> + }
>>>>>>> + } else if (connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_eDP) {
>>>>>>> + /* eDP */
>>>>>>> + if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> + DP_EDP_CONFIGURATION_CAP, &tmp) == 1) {
>>>>>>> + if (tmp & 1)
>>>>>>> + panel_mode = DP_PANEL_MODE_INTERNAL_DP2_MODE;
>>>>>>> + }
>>>>>>> }
>>>>>>> }
>>>>>>>
>>>>>>> @@ -511,6 +525,9 @@ bool radeon_dp_needs_link_train(struct
>>>>>>> radeon_connector *radeon_connector)
>>>>>>> u8 link_status[DP_LINK_STATUS_SIZE];
>>>>>>> struct radeon_connector_atom_dig *dig =
>>>>>>> radeon_connector->con_priv;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return false;
>>>>>>> +
>>>>>>> if
>>>>>>> (drm_dp_dpcd_read_link_status(&radeon_connector->ddc_bus-
>>> aux,
>>>>>>> link_status)
>>>>>>> <= 0)
>>>>>>> return false;
>>>>>>> @@ -531,7 +548,7 @@ void radeon_dp_set_rx_power_state(struct
>>>>>>> drm_connector *connector,
>>>>>>> dig_connector = radeon_connector->con_priv;
>>>>>>>
>>>>>>> /* power up/down the sink */
>>>>>>> - if (dig_connector->dpcd[0] >= 0x11) {
>>>>>>> + if (radeon_connector->ddc_bus && dig_connector->dpcd[0] >=
>>>>>>> 0x11) {
>>>>>>> drm_dp_dpcd_writeb(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_SET_POWER, power_state);
>>>>>>> usleep_range(1000, 2000);
>>>>>>> @@ -834,7 +851,8 @@ void radeon_dp_link_train(struct
>> drm_encoder
>>>>>>> *encoder,
>>>>>>> else
>>>>>>> dp_info.enc_id |= ATOM_DP_CONFIG_LINK_A;
>>>>>>>
>>>>>>> - if (drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_MAX_LANE_COUNT, &tmp)
>>>>>>> + if (radeon_connector->ddc_bus &&
>>>>>>> + drm_dp_dpcd_readb(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_MAX_LANE_COUNT, &tmp)
>>>>>>> == 1) {
>>>>>>> if (ASIC_IS_DCE5(rdev) && (tmp & DP_TPS3_SUPPORTED))
>>>>>>> dp_info.tp3_supported = true;
>>>>>>> @@ -850,7 +868,7 @@ void radeon_dp_link_train(struct
>> drm_encoder
>>>>>>> *encoder,
>>>>>>> dp_info.connector = connector;
>>>>>>> dp_info.dp_lane_count = dig_connector->dp_lane_count;
>>>>>>> dp_info.dp_clock = dig_connector->dp_clock;
>>>>>>> - dp_info.aux = &radeon_connector->ddc_bus->aux;
>>>>>>> + dp_info.aux = radeon_connector->ddc_bus ?
>>>>>>> &radeon_connector->ddc_bus->aux : 0;
>>>>>>>
>>>>>>> if (radeon_dp_link_train_init(&dp_info))
>>>>>>> goto done;
>>>>>>> diff --git a/drivers/gpu/drm/radeon/radeon_connectors.c
>>>>>>> b/drivers/gpu/drm/radeon/radeon_connectors.c
>>>>>>> index b79f3b0..cec30c9 100644
>>>>>>> --- a/drivers/gpu/drm/radeon/radeon_connectors.c
>>>>>>> +++ b/drivers/gpu/drm/radeon/radeon_connectors.c
>>>>>>> @@ -328,31 +328,32 @@ static void
>> radeon_connector_get_edid(struct
>>>>>>> drm_connector *connector)
>>>>>>> if (radeon_connector->router.ddc_valid)
>>>>>>> radeon_router_select_ddc_port(radeon_connector);
>>>>>>>
>>>>>>> - if
>>>>>>>
>> ((radeon_connector_encoder_get_dp_bridge_encoder_id(connector) !=
>>>>>>> - ENCODER_OBJECT_ID_NONE) &&
>>>>>>> - radeon_connector->ddc_bus->has_aux) {
>>>>>>> - radeon_connector->edid = drm_get_edid(connector,
>>>>>>> - &radeon_connector->ddc_bus->aux.ddc);
>>>>>>> - } else if ((connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_DisplayPort) ||
>>>>>>> - (connector->connector_type ==
>> DRM_MODE_CONNECTOR_eDP)) {
>>>>>>> - struct radeon_connector_atom_dig *dig =
>>>>>>> radeon_connector->con_priv;
>>>>>>> -
>>>>>>> - if ((dig->dp_sink_type ==
>> CONNECTOR_OBJECT_ID_DISPLAYPORT ||
>>>>>>> - dig->dp_sink_type == CONNECTOR_OBJECT_ID_eDP) &&
>>>>>>> - radeon_connector->ddc_bus->has_aux)
>>>>>>> - radeon_connector->edid =
>>>>>>> drm_get_edid(&radeon_connector->base,
>>>>>>> + if (radeon_connector->ddc_bus) {
>>>>>>> + if
>>>>>>>
>> ((radeon_connector_encoder_get_dp_bridge_encoder_id(connector) !=
>>>>>>> + ENCODER_OBJECT_ID_NONE) &&
>>>>>>> + radeon_connector->ddc_bus->has_aux) {
>>>>>>> + radeon_connector->edid = drm_get_edid(connector,
>>>>>>> &radeon_connector->ddc_bus->aux.ddc);
>>>>>>> - else if (radeon_connector->ddc_bus)
>>>>>>> + } else if ((connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_DisplayPort) ||
>>>>>>> + (connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_eDP)) {
>>>>>>> + struct radeon_connector_atom_dig *dig =
>>>>>>> radeon_connector->con_priv;
>>>>>>> +
>>>>>>> + if ((dig->dp_sink_type ==
>>>>>>> CONNECTOR_OBJECT_ID_DISPLAYPORT ||
>>>>>>> + dig->dp_sink_type == CONNECTOR_OBJECT_ID_eDP) &&
>>>>>>> + radeon_connector->ddc_bus->has_aux)
>>>>>>> + radeon_connector->edid =
>>>>>>> drm_get_edid(&radeon_connector->base,
>>>>>>> + &radeon_connector->ddc_bus->aux.ddc);
>>>>>>> + else
>>>>>>> + radeon_connector->edid =
>>>>>>> drm_get_edid(&radeon_connector->base,
>>>>>>> + &radeon_connector->ddc_bus->adapter);
>>>>>>> + } else if (vga_switcheroo_handler_flags() &
>>>>>>> VGA_SWITCHEROO_CAN_SWITCH_DDC &&
>>>>>>> + connector->connector_type ==
>>>>>>> DRM_MODE_CONNECTOR_LVDS) {
>>>>>>> + radeon_connector->edid =
>>>>>>> drm_get_edid_switcheroo(&radeon_connector->base,
>>>>>>> + &radeon_connector->ddc_bus->adapter);
>>>>>>> + } else {
>>>>>>> radeon_connector->edid =
>>>>>>> drm_get_edid(&radeon_connector->base,
>>>>>>> &radeon_connector->ddc_bus->adapter);
>>>>>>> - } else if (vga_switcheroo_handler_flags() &
>>>>>>> VGA_SWITCHEROO_CAN_SWITCH_DDC &&
>>>>>>> - connector->connector_type ==
>> DRM_MODE_CONNECTOR_LVDS &&
>>>>>>> - radeon_connector->ddc_bus) {
>>>>>>> - radeon_connector->edid =
>>>>>>> drm_get_edid_switcheroo(&radeon_connector->base,
>>>>>>> - &radeon_connector->ddc_bus->adapter);
>>>>>>> - } else if (radeon_connector->ddc_bus) {
>>>>>>> - radeon_connector->edid =
>>>>>>> drm_get_edid(&radeon_connector->base,
>>>>>>> - &radeon_connector->ddc_bus->adapter);
>>>>>>> + }
>>>>>>> }
>>>>>>>
>>>>>>> if (!radeon_connector->edid) {
>>>>>>> @@ -1312,6 +1313,7 @@ radeon_dvi_detect(struct drm_connector
>>>>>>> *connector, bool force)
>>>>>>> continue;
>>>>>>> list_radeon_connector =
>>>>>>> to_radeon_connector(list_connector);
>>>>>>> if (list_radeon_connector->shared_ddc &&
>>>>>>> + radeon_connector->ddc_bus &&
>>>>>>> (list_radeon_connector->ddc_bus->rec.i2c_id ==
>>>>>>> radeon_connector->ddc_bus->rec.i2c_id)) {
>>>>>>> /* cases where both connectors are
>>>>>>> digital */
>>>>>>> diff --git a/drivers/gpu/drm/radeon/radeon_dp_mst.c
>>>>>>> b/drivers/gpu/drm/radeon/radeon_dp_mst.c
>>>>>>> index de504ea..89e91f3 100644
>>>>>>> --- a/drivers/gpu/drm/radeon/radeon_dp_mst.c
>>>>>>> +++ b/drivers/gpu/drm/radeon/radeon_dp_mst.c
>>>>>>> @@ -661,7 +661,7 @@ radeon_dp_mst_init(struct radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> {
>>>>>>> struct drm_device *dev = radeon_connector->base.dev;
>>>>>>>
>>>>>>> - if (!radeon_connector->ddc_bus->has_aux)
>>>>>>> + if (!radeon_connector->ddc_bus ||
>>>>>>> !radeon_connector->ddc_bus->has_aux)
>>>>>>> return 0;
>>>>>>>
>>>>>>> radeon_connector->mst_mgr.cbs = &mst_cbs;
>>>>>>> @@ -688,6 +688,9 @@ radeon_dp_mst_probe(struct
>> radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> if (dig_connector->dpcd[DP_DPCD_REV] < 0x12)
>>>>>>> return 0;
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus ||
>>>>>>> !radeon_connector->ddc_bus->has_aux)
>>>>>>> + return 0;
>>>>>>> +
>>>>>>> ret = drm_dp_dpcd_read(&radeon_connector->ddc_bus->aux,
>>>>>>> DP_MSTM_CAP, msg,
>>>>>>> 1);
>>>>>>> if (ret) {
>>>>>>> @@ -711,7 +714,9 @@ radeon_dp_mst_check_status(struct
>>>>>>> radeon_connector
>>>>>>> *radeon_connector)
>>>>>>> struct radeon_connector_atom_dig *dig_connector =
>>>>>>> radeon_connector->con_priv;
>>>>>>> int retry;
>>>>>>>
>>>>>>> - if (dig_connector->is_mst) {
>>>>>>> + if (dig_connector->is_mst &&
>>>>>>> + radeon_connector->ddc_bus &&
>>>>>>> + radeon_connector->ddc_bus->has_aux) {
>>>>>>> u8 esi[16] = { 0 };
>>>>>>> int dret;
>>>>>>> int ret = 0;
>>>>>>> diff --git a/drivers/gpu/drm/radeon/radeon_i2c.c
>>>>>>> b/drivers/gpu/drm/radeon/radeon_i2c.c
>>>>>>> index 9590bcd..c18f7ba 100644
>>>>>>> --- a/drivers/gpu/drm/radeon/radeon_i2c.c
>>>>>>> +++ b/drivers/gpu/drm/radeon/radeon_i2c.c
>>>>>>> @@ -63,6 +63,9 @@ bool radeon_ddc_probe(struct
>> radeon_connector
>>>>>>> *radeon_connector, bool use_aux)
>>>>>>> if (radeon_connector->router.ddc_valid)
>>>>>>> radeon_router_select_ddc_port(radeon_connector);
>>>>>>>
>>>>>>> + if (!radeon_connector->ddc_bus)
>>>>>>> + return false;
>>>>>>> +
>>>>>>> if (use_aux) {
>>>>>>> ret = i2c_transfer(&radeon_connector->ddc_bus->aux.ddc,
>>>>>>> msgs, 2);
>>>>>>> } else {
>>>>>>> _______________________________________________
>>>>>>> dri-devel mailing list
>>>>>>> dri-devel at lists.freedesktop.org
>>>>>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>>>>>>
>>> _______________________________________________
>>> dri-devel mailing list
>>> dri-devel at lists.freedesktop.org
>>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>>
>
More information about the dri-devel
mailing list