Re: [PATCH 16/17] [NOT-FOR-MERGE] media: atomsip: pci: add DMI match for Microsoft Surface 3 with broken DMI (OEMB)

Tsuchiya Yuto
2021-10-21T09:46:35Z

On Mon, 2021-10-18 at 09:56 +0200, Hans de Goede wrote:
> Hi,
>
> On 10/17/21 18:19, Tsuchiya Yuto wrote:
> > This commit is added for Surface 3 with broken DMI table. HACK-ish.
> > Not intended for upstreaming. Thus, NOT-FOR-MERGE. But, if someone
> > knows a nicer way to address this, comments are welcome...
> >
> > > 8-----------------------------------------------------------------8<
> >
> > On some Microsoft Surface 3, the DMI table gets corrupted for unknown
> > reasons and breaks existing DMI matching used for device-specific quirks.
> >
> > This commit adds the (broken) DMI data into dmi_system_id tables used
> > for quirks so that the driver can enable quirks even on the affected
> > systems.
> >
> > On affected systems, the DMI data will look like this:
> >
> > $ grep . /sys/devices/virtual/dmi/id/{bios_vendor,board_name,board_vendor,\
> > chassis_vendor,product_name,sys_vendor}
> > /sys/devices/virtual/dmi/id/bios_vendor:American Megatrends Inc.
> > /sys/devices/virtual/dmi/id/board_name:OEMB
> > /sys/devices/virtual/dmi/id/board_vendor:OEMB
> > /sys/devices/virtual/dmi/id/chassis_vendor:OEMB
> > /sys/devices/virtual/dmi/id/product_name:OEMB
> > /sys/devices/virtual/dmi/id/sys_vendor:OEMB
>
> I wonder what the bios_date field contains ? Typically when the DMI strings
> are no good (e.g. often they contain "Default String" or "To be filled by OEM")
> we add a check on the bios-date, which together with the broken strings is
> considered unique enough to still allow a match with broken strings in the
> kernel.

Thank you so much for the comment :-)

Here is the full output of "/sys/devices/virtual/dmi/id/*" (not showing
files that need root permission to read):

$ grep . /sys/devices/virtual/dmi/id/*
/sys/devices/virtual/dmi/id/bios_date:03/09/2015
/sys/devices/virtual/dmi/id/bios_release:5.6
/sys/devices/virtual/dmi/id/bios_vendor:American Megatrends Inc.
/sys/devices/virtual/dmi/id/bios_version:1.51116.238
/sys/devices/virtual/dmi/id/board_name:OEMB
grep: /sys/devices/virtual/dmi/id/board_serial: Permission denied
/sys/devices/virtual/dmi/id/board_vendor:OEMB
/sys/devices/virtual/dmi/id/board_version:00
grep: /sys/devices/virtual/dmi/id/chassis_serial: Permission denied
/sys/devices/virtual/dmi/id/chassis_type:9
/sys/devices/virtual/dmi/id/chassis_vendor:OEMB
/sys/devices/virtual/dmi/id/modalias:dmi:bvnAmericanMegatrendsInc.:bvr1.51116.238:bd03/09/2015:br5.6:svnOEMB:pnOEMB:pvrB16D0SM1C4G1X1:rvnOEMB:rnOEMB:rvr00:cvnOEMB:ct9:cvr:sku:
grep: /sys/devices/virtual/dmi/id/power: Is a directory
/sys/devices/virtual/dmi/id/product_name:OEMB
grep: /sys/devices/virtual/dmi/id/product_serial: Permission denied
grep: /sys/devices/virtual/dmi/id/product_uuid: Permission denied
/sys/devices/virtual/dmi/id/product_version:B16D0SM1C4G1X1
grep: /sys/devices/virtual/dmi/id/subsystem: Is a directory
/sys/devices/virtual/dmi/id/sys_vendor:OEMB
/sys/devices/virtual/dmi/id/uevent:MODALIAS=dmi:bvnAmericanMegatrendsInc.:bvr1.51116.238:bd03/09/2015:br5.6:svnOEMB:pnOEMB:pvrB16D0SM1C4G1X1:rvnOEMB:rnOEMB:rvr00:cvnOEMB:ct9:cvr:sku:

The "bios_date" ("03/09/2015") looks not broken.

I also noticed when writing this mail, regarding the ones that need root
permission to read, "board_serial" and "chassis_serial" are now empty.
"product_serial" now shows "OEM":

$ sudo cat /sys/devices/virtual/dmi/id/product_serial
OEM

"product_uuid" looks not broken.

> Also have you tried doing something like "load bios/setup defaults" in
> the BIOS setup ? Maybe that helps ?

Unfortunately, there is no option like this...

Regards,
Tsuchiya Yuto