[U-Boot] [PATCH] i2c: intel_i2c: SMBus driver PCI addition (e.g. BayTrail)

[Bin Meng]

Simon, Stefan,

On Tue, Jul 26, 2016 at 8:13 PM, Stefan Roese <sr at denx.de> wrote:
> Hi Simon,
>
> On 25.07.2016 04:07, Simon Glass wrote:
>>
>> On 28 June 2016 at 07:44, Stefan Roese <sr at denx.de> wrote:
>>>
>>> This patch adds support for the SMBus block read/write functionality.
>>> Other protocols like the SMBus quick command need to get added
>>> if this is needed.
>>>
>>> This patch also removed the SMBus related defines from the Ivybridge
>>> pch.h header. As they are integrated in this driver and should be
>>> used from here. This change is added in this patch to avoid compile
>>> breakage to keep the source git bisectable.
>>>
>>> Tested on a congatec BayTrail board to configure the SMSC2513 USB
>>> hub.
>>>
>>> Signed-off-by: Stefan Roese <sr at denx.de>
>>> Cc: Bin Meng <bmeng.cn at gmail.com>
>>> Cc: Simon Glass <sjg at chromium.org>
>>> Cc: Heiko Schocher <hs at denx.de>
>>> ---
>>> Simon, I'm not sure if this change breaks your Ivybridge targets
>>> using the probe part of this driver. Could you please let me
>>> know if this works? Or let me know what needs changes here?
>>
>>
>> Yes this breaks booting on link. Something odd is going on because the
>> call to set up I2C in ivybridge's print_cpuinfo() returns a very
>> strange error -726376.
>
>
> Hmmm, very strange.
>
>> But I then enabled CONFIG_CMD_I2C and it boots. However 'i2c probe'
>> produces a lot of errors like this:
>>
>> ERROR: len=0 on read
>> smbus_block_read (107): dev=0x3b offs=0x0 len=0x1
>> smbus_block_read (136): count=0 (len=1)
>
>
> A general question:
>
> Is the SMBus controller on Ivybridge also exported as PCI device? If
> yes, can't we just use the PCI code as done for BayTrail for this
> platform as well? And get rid of the platform specific stuff this
> way?
>
> Could you send me the output of "pci 0 long" on this platform?
>

Do you plan to get this I2C merged in this release? If so, please work
this out .. I don't feel comfortable to apply this at present.

Regards,
Bin