Re: atomisp kernel driver(s)

[Patrik Gfeller <patrik.gfeller@gmail.com>]

On 26.04.20 18:50, Mauro Carvalho Chehab wrote:
> Em Sun, 26 Apr 2020 13:38:19 +0200
> Patrik Gfeller <patrik.gfeller@gmail.com> escreveu:
>
>> On 25.04.20 13:22, Mauro Carvalho Chehab wrote:
>>> Hi Patrik,
>>>
>>> Em Fri, 24 Apr 2020 12:07:30 +0200
>>> Patrik Gfeller <patrik.gfeller@gmail.com> escreveu:
>>>   
>>>> On 24.04.20 11:10, Patrik Gfeller wrote:
>>>>> On 24.04.20 10:52, Patrik Gfeller wrote:
>>>>>> On 22.04.20 21:13, Mauro Carvalho Chehab wrote:
>>>>>>> Em Wed, 22 Apr 2020 19:56:56 +0200
>>>>>>> Patrik Gfeller <patrik.gfeller@gmail.com> escreveu:
>>>>>>>      
>>>>>>>> On 20.04.20 22:47, Mauro Carvalho Chehab wrote:
>>>>>>>>> Em Mon, 20 Apr 2020 20:27:25 +0200
>>>>>>>>> Patrik Gfeller <patrik.gfeller@gmail.com> escreveu:
>>>>>>>>>> Me again ... sorry to ask such a basic question, but I can't get
>>>>>>>>>> your
>>>>>>>>>> modified source code. I get the following error:
>>>>>>>>>>        > git clone https://git.linuxtv.$ sudo make M=drivers/staging/media/atomisp/ modules_install
>>>>>>>>>> org/mchehab/experimental.git/
>>>>>>>>>> Cloning into 'experimental'...
>>>>>>>>>> warning: adding alternate object store:
>>>>>>>>>> https://git.linuxtv.org/git/linux.git/
>>>>>>>>>> warning: adding alternate object store:
>>>>>>>>>> https://git.linuxtv.org/git/media_tree.git/
>>>>>>>>>> warning: adding alternate object store:
>>>>>>>>>> https://git.linuxtv.org/git/linux.git/
>>>>>>>>>> error: Unable to find fc8670d1f72b746ff3a5fe441f1fca4c4dba0e6f under
>>>>>>>>>> https://git.linuxtv.org/mchehab/experimental.git
>>>>>>>>>> Cannot obtain needed object fc8670d1f72b746ff3a5fe441f1fca4c4dba0e6f
>>>>>>>>>> while processing commit 6d80bfc14608f4bb5514b79721d30b486f50c987.
>>>>>>>>>> error: fetch failed.
>>>>>>>>>>
>>>>>>>>>> Do I use the wrong command?
>>>>>>>>> Better to use git:// url:
>>>>>>>>>
>>>>>>>>>       git clone git://git.linuxtv.org/mchehab/experimental.git/
>>>>>>>> I was able to download and compile the code. I installed the kernel
>>>>>>>> and
>>>>>>>> tried to boot; unfortunately it hangs with the message "Loading
>>>>>>>> initial
>>>>>>>> ramdisk ..." - after I start the old kernel I check kern.log and
>>>>>>>> syslog
>>>>>>>> - but I do not see entries from the failed boot attempt. I'll read
>>>>>>>> into
>>>>>>>> the topic and try around. This will take some time ... so there
>>>>>>>> will be
>>>>>>>> a dealy, but it's not that I do not care or lacking interest, I just
>>>>>>>> first have to sort this out.
>>>>>>> Well, try to build it first without the atomisp driver. This would
>>>>>>> allow
>>>>>>> you to see what's going on.
>>>>>> I was able to solve the problem I had with the ramdisk - I had to
>>>>>> strip the kernel modules, probably the ramdisk file was too big.
>>>>>>
>>>>>> It is possible to boot with the atomisp driver, but I can not see the
>>>>>> camera yet - but maybe that's due to missing firmware, as there were
>>>>>> warnings when I installed the kernel that firmware files are missing.
>>>> I've added the missing firmware files and now I do not have warnings
>>>> when I create the ramdisk. Unfortunately it makes no difference - the
>>>> device does not work yet (dmesg looks the same).
>>>>>> The following I found in dmesg:
>>>>>>
>>>>>> [    9.331011] kernel: atomisp_ov2680: module is from the staging
>>>>>> directory, the quality is unknown, you have been warned.
>>>>>> [    9.402456] kernel: ov2680 i2c-OVTI2680:00: gmin: initializing
>>>>>> atomisp module subdev data.PMIC ID 1
>>>>>> [    9.421113] kernel: acpi OVTI2680:00: Failed to find gmin variable
>>>>>> OVTI2680:00_CamClk
>>>>>> [    9.433478] kernel: acpi OVTI2680:00: Failed to find gmin variable
>>>>>> OVTI2680:00_ClkSrc
>>>>>> [    9.443146] kernel: acpi OVTI2680:00: Failed to find gmin variable
>>>>>> OVTI2680:00_CsiPort
>>>>>> [    9.456677] kernel: acpi OVTI2680:00: Failed to find gmin variable
>>>>>> OVTI2680:00_CsiLanes
>>>>>> [    9.479411] kernel: ov2680 i2c-OVTI2680:00: supply V1P8SX not
>>>>>> found, using dummy regulator
>>>>>> [    ...
>>>>>> [    9.510282] kernel: ov2680 i2c-OVTI2680:00: supply V2P8SX not
>>>>>> found, using dummy regulator
>>>>>> [    ...
>>>>>> [    9.532284] kernel: ov2680 i2c-OVTI2680:00: supply V1P2A not
>>>>>> found, using dummy regulator
>>>>>> [    9.536200] kernel: ov2680 i2c-OVTI2680:00: supply VPROG4B not
>>>>>> found, using dummy regulator
>>>>>> [   ...'
>>>>>> [    9.592064] kernel: ov2680 i2c-OVTI2680:00: unable to set PMC rate 1
>>>>>> [    9.623628] kernel: ov2680 i2c-OVTI2680:00: camera pdata: port: 0
>>>>>> lanes: 1 order: 00000002
>>>>>> [    9.628258] kernel: ov2680 i2c-OVTI2680:00: sensor_revision id =
>>>>>> 0x2680, rev= 0
>>>>>> [    9.636582] kernel: ov2680 i2c-OVTI2680:00: register atomisp i2c
>>>>>> module type 1
>>>>>>
>>>>>> The first signs of live :-) ... I'll try to find the firmware files
>>>>>> to see if it makes a difference.
>>> Atomisp driver uses ACPI to detect the camera configuration. As you
>>> can see at drivers/staging/media/atomisp/i2c/atomisp-ov2680.c:
>>>
>>> 	static const struct acpi_device_id ov2680_acpi_match[] = {
>>> 	        {"XXOV2680"},
>>> 	        {"OVTI2680"},
>>> 	        {},
>>> 	};
>>> 	MODULE_DEVICE_TABLE(acpi, ov2680_acpi_match);
>>>
>>> The regulator data is parsed at
>>> drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:
>>>
>>>           if (pmic_id == PMIC_REGULATOR) {
>>>                   gmin_subdevs[i].v1p8_reg = regulator_get(dev, "V1P8SX");
>>>                   gmin_subdevs[i].v2p8_reg = regulator_get(dev, "V2P8SX");
>>>                   gmin_subdevs[i].v1p2_reg = regulator_get(dev, "V1P2A");
>>>                   gmin_subdevs[i].v2p8_vcm_reg = regulator_get(dev, "VPROG4B");
>>>
>>>                   /* Note: ideally we would initialize v[12]p8_on to the
>>>                    * output of regulator_is_enabled(), but sadly that
>>>                    * API is broken with the current drivers, returning
>>>                    * "1" for a regulator that will then emit a
>>>                    * "unbalanced disable" WARNing if we try to disable
>>>                    * it.
>>>                    */
>>>           }
>>>
>>> There are two things that could be the cause of this issue:
>>>
>>> 1) Some patch could have broken support for it.
>>>
>>> Doing a:
>>>
>>> 	git diff a49d25364dfb drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c
>>>
>>> will allow you to check the changes on this file.
>>>
>>> 2) Maybe recent BIOSes may have changed the names of the ACPI variables.
>>>
>>> For instance, from the code, the driver should be seeking for those
>>> variables for OV2680 (and several others that seem to be common among
>>> multiple combinations):
>>>
>>> 	XXOV2680:00_CsiPort
>>> 	XXOV2680:00_CsiLanes
>>> 	XXOV2680:00_CamClk
>>>
>>> It would be possible, that, on a modern BIOS, such vars were, for example,
>>> renamed to 'XXOV2680_V2*'.
>> Thank you for the explanations. I've read the article about ACPI and
>> have now a basic idea what it is.
>>
>> I tried to figure out if the ACPI variable names changed ... in the ACPI
>> dump the variables seem to match the code (if I understood correctly). I
>> tried to scan the firmware file to check if there's a hint regarding a
>> changed variable:
>>
>> $ strings shisp_2401a0_v21.bin | grep 2680
>> $ strings shisp_2401a0_v21.bin | grep OV
> No, you're looking at the wrong place. This should be at the system
> board's BIOS, and not at something that the driver would load.
>
> Just run (as root):
>
> 	# dmidecode
>
> and check the name of your board. It should be similar to this:
>
> 	...
> 	System Information
> 	        Manufacturer: Intel Corporation
> 	        Product Name: (something)
>
> The "(something)" is the board name. The atomisp driver will seek for
> it. So, you need to patch the driver (using the example I gave) in
> order for it to look at the right DMI_MATCH() table. Right now,
> the driver knows only those:
>
> 	$ git grep DMI_MATCH drivers/staging/media/atomisp/
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_NAME, "BYT-T FFD8"),
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_NAME, "T100TA"),
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_NAME, "TABLET"),	
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_VERSION, "MRD 7"),
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_NAME, "ST70408"),
> 	drivers/staging/media/atomisp/platform/intel-mid/atomisp_gmin_platform.c:                       DMI_MATCH(DMI_BOARD_NAME, "VTA0803"),
>
> Your asus board should likely use "ASUS", "_ASUS_" or something similar.
> So, you should take a look on the patch I sent you and modify it to
> match whatever name dmidecode printed.
>
> See for example this patch:
>
> 	https://www.spinics.net/lists/linux-media/msg126880.html
>
> If it finds the right table, it should end by calling gmin_subdev_add(),
> with should use DTST table, also from the ACPI table inside the system's BIOS.
Now I understood :-). I've made the modifications as you explained and 
indeed the errors regarding

OVTI2680:00_CamClk
OVTI2680:00_ClkSrc
OVTI2680:00_CsiPort
OVTI2680:00_CsiLanes

are gone. Now we have the following in dmesg:

[    8.815960] kernel: mc: Linux media interface: v0.10
[    8.858458] kernel: videodev: Linux video capture interface: v2.00
[    8.876864] kernel: input: Intel HID events as 
/devices/pci0000:00/INT33D5:00/input/input16
[    8.887625] kernel: 8086228A:01: ttyS5 at MMIO 0x91a1f000 (irq = 40, 
base_baud = 2764800) is a 16550A
[    8.894655] kernel: dw_dmac INTL9C60:01: DesignWare DMA Controller, 8 
channels
[    8.929818] kernel: atomisp_ov2680: module is from the staging 
directory, the quality is unknown, you have been warned.
[    8.989630] kernel: ov2680 i2c-OVTI2680:00: gmin: initializing 
atomisp module subdev data.PMIC ID 1
[    8.989887] kernel: ov2680 i2c-OVTI2680:00: supply V1P8SX not found, 
using dummy regulator
[    8.989954] kernel: ov2680 i2c-OVTI2680:00: supply V2P8SX not found, 
using dummy regulator
[    8.989977] kernel: ov2680 i2c-OVTI2680:00: supply V1P2A not found, 
using dummy regulator
[    8.989998] kernel: ov2680 i2c-OVTI2680:00: supply VPROG4B not found, 
using dummy regulator
[    9.033505] kernel: ov2680 i2c-OVTI2680:00: unable to set PMC rate 1
[    9.061511] kernel: ov2680 i2c-OVTI2680:00: camera pdata: port: 0 
lanes: 1 order: 00000002
[    9.065178] kernel: ov2680 i2c-OVTI2680:00: sensor_revision id = 
0x2680, rev= 0
[    9.071095] kernel: ov2680 i2c-OVTI2680:00: register atomisp i2c 
module type 1

Laurent explained me how to enable internal debug messages. I'll read 
more about this to understand how to use it and hope this will give a 
more detailed insight.


great to see some progress :-),

thanks and kind regards,

Patrik


>
> Thanks,
> Mauro