On 17.04.2022 04:27, Wolfram Sang wrote:
> On Mon, Dec 06, 2021 at 10:18:49PM +0100, Heiner Kallweit wrote:
>> Currently we use the following feature definitions. However, according to
>> the respective datasheets, also ICH/ICH0/ICH2/ICH3/ICH4 support I2C block
>> read. The implementation we have should work also on these chip versions.
>>
>> The commit message of 6342064cad7a ("i2c-i801: Implement I2C block read
>> support") states that i2c block read is supported from ICH5 only.
>> This doesn't seem to be true. Or is this feature broken on older chip
>> versions?
>>
>> To me it seems we could remove FEATURE_I2C_BLOCK_READ because all chip
>> versions support this feature. Below is an experimental patch, for the
>> ones with test hw. A test case could be to use decode-dimms that
>> uses i2c block read to read the EEPROM content.
>>
>> * Supports the following Intel I/O Controller Hubs (ICH):
>> *
>> * I/O Block I2C
>> * region SMBus Block proc. block
>> * Chip name PCI ID size PEC buffer call read
>> * ---------------------------------------------------------------------------
>> * 82801AA (ICH) 0x2413 16 no no no no
>> * 82801AB (ICH0) 0x2423 16 no no no no
>> * 82801BA (ICH2) 0x2443 16 no no no no
>> * 82801CA (ICH3) 0x2483 32 soft no no no
>> * 82801DB (ICH4) 0x24c3 32 hard yes no no
>> * 82801E (ICH5) 0x24d3 32 hard yes yes yes
>
> Any reason you skipped this patch in your latest series?
>
Supporting I2C block read on all chip versions is part of patch 4 in the
series. I didn't remove feature flag FEATURE_I2C_BLOCK_READ yet to give users
the chance to disable the feature via module parameter in case of problems.
