Re: [PATCH v9 0/5] staging: vc04_services: vchiq: Register devices with a custom bus_type

[Stefan Wahren <stefan.wahren@i2se.com>]

Hi Umang,

Am 19.07.23 um 18:54 schrieb Umang Jain:
> Hi,
> 
> One comment,
> 
> On 7/19/23 10:14 PM, Umang Jain wrote:
>> The patch series added a new bus type vchiq_bus_type and registers
>> child devices in order to move them away from using platform
>> device/driver.
>>
>> Patch 1/5 and 2/5 adds a new bus_type and registers them to vchiq
>> interface
>>
>> Patch 3/5 and 4/5 moves the bcm2835-camera and bcm2835-audio
>> to the new bus respectively
>>
>> Patch 5/5 removes a platform registeration helper which is no
>> longer required.
>>
>> Changes in v9:
>> - Fix module autoloading
> 
> While the autoloading of bcm2835-audio, bcm2835-camera is fixed as part 
> of this series, there is one WARN coming in when bcm2835-audio is loaded 
> regarding dma_alloc_attr
> 
> dmesg output: https://paste.debian.net/plain/1286359

is it possible that after your patch series no DMA mask like 
DMA_BIT_MASK(32) is provided?

> 
> I am investigating further...
>> - Implement bus_type's probe() callback to load drivers
>> - Implement bus_type's uevent() to make sure appropriate drivers are
>>    loaded when device are registed from vchiq.
>>
>> Changes in v8:
>> - Drop dual licensing. Instead use GPL-2.0 only for patch 1/5
>>
>> Changes in v7:
>> (5 out of 6 patches from v6 merged)
>> - Split the main patch (6/6) as requested.
>> - Use struct vchiq_device * instead of struct device * in
>>    all bus functions.
>> - Drop additional name attribute displayed in sysfs (redundant info)
>> - Document vchiq_interface doesn't enumerate device discovery
>> - remove EXPORT_SYMBOL_GPL(vchiq_bus_type)
>>
>> Changes in v6:
>> - Split struct device and struct driver wrappers in vchiq_device.[ch]
>> - Move vchiq_bus_type definition to vchiq_device.[ch] as well
>> - return error on bus_register() failure
>> - drop dma_set_mask_and_coherent
>> - trivial variable name change
>>
>> Changes in v5:
>> - Fixup missing "staging: " in commits' subject line
>> - No code changes from v4
>>
>> Changes in v4:
>> - Introduce patches to drop include directives from Makefile
>>
>> Changes in v3:
>> - Rework entirely to replace platform devices/driver model
>>
>> -v2:
>> https://lore.kernel.org/all/20221222191500.515795-1-umang.jain@ideasonboard.com/
>>
>> -v1:
>> https://lore.kernel.org/all/20221220084404.19280-1-umang.jain@ideasonboard.com/
>>
>> Umang Jain (5):
>>    staging: vc04_services: vchiq_arm: Add new bus type and device type
>>    staging: vc04_services: vchiq_arm: Register vchiq_bus_type
>>    staging: bcm2835-camera: Register bcm2835-camera with vchiq_bus_type
>>    staging: bcm2835-audio: Register bcm2835-audio with vchiq_bus_type
>>    staging: vc04_services: vchiq_arm: Remove vchiq_register_child()
>>
>>   drivers/staging/vc04_services/Makefile        |   1 +
>>   .../vc04_services/bcm2835-audio/bcm2835.c     |  20 ++--
>>   .../bcm2835-camera/bcm2835-camera.c           |  17 +--
>>   .../interface/vchiq_arm/vchiq_arm.c           |  48 ++++-----
>>   .../interface/vchiq_arm/vchiq_device.c        | 102 ++++++++++++++++++
>>   .../interface/vchiq_arm/vchiq_device.h        |  54 ++++++++++
>>   6 files changed, 196 insertions(+), 46 deletions(-)
>>   create mode 100644 
>> drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.c
>>   create mode 100644 
>> drivers/staging/vc04_services/interface/vchiq_arm/vchiq_device.h
>>
>