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

[Heiko Schocher <hs@denx.de>]

Hello Bin,

Am 05.08.2016 um 07:46 schrieb Bin Meng:
> Simon, Stefan,
>
> On Tue, Jul 26, 2016 at 8:13 PM, Stefan Roese <sr@denx.de> wrote:
>> Hi Simon,
>>
>> On 25.07.2016 04:07, Simon Glass wrote:
>>>
>>> On 28 June 2016 at 07:44, Stefan Roese <sr@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@denx.de>
>>>> Cc: Bin Meng <bmeng.cn@gmail.com>
>>>> Cc: Simon Glass <sjg@chromium.org>
>>>> Cc: Heiko Schocher <hs@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.

Full Ack.

bye,
Heiko
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