Re: [PATCH 0/3 v2] i2c: i801: enable irq

From: Daniel Kurtz
Date: Wed May 09 2012 - 02:36:24 EST

Jean? Anyone? ping?

On Mon, Feb 20, 2012 at 7:23 PM, Daniel Kurtz <djkurtz@xxxxxxxxxxxx> wrote:
> On Fri, Jan 6, 2012 at 7:35 PM, Jean Delvare <khali@xxxxxxxxxxxx> wrote:
>> Hi Daniel,
>> On Fri,  6 Jan 2012 18:58:19 +0800, Daniel Kurtz wrote:
>>> This is a second version of a set of patches enables the Intel PCH SMBus
>>> controller interrupt.  It refactors the second two patches a little bit by
>>> relying on DEV_ERR interrupt for timeouts, instead of using an explicit
>>> wait_event_timeout.
>>> The first attempt received absolutely no response. Maybe this time someone
>>> will be interested.
>> I was on vacation. But I am very interested and will review and test
>> your patches. There have been several attempts to add IRQ support to
>> i2c-i801 in the past but each time there was a blocker issue which
>> prevented it from making it into mainline. Hopefully this time we'll
>> get it there!
>>> The SMBus Host Controller Interrupt can signify:
>>>  INTR - the end of a complete transaction
>>>  DEV_ERR - that a device did not ACK a transaction
>>>  BYTE_DONE - the completion of a single byte during a byte-by-byte transaction
>>> This patchset arrives with the following caveats:
>>>  1)  It has only been tested with a Cougar Point (Intel 6 Series PCH) SMBus
>>> controller, so the irq is only enabled for that chip type.
>> I can test on ICH10 easily, and also on ICH7 and ICH3-M if needed.
>>>  2) It has not been tested with any devices that do transactions that use the
>>>     PEC.  In fact, I believe that an additional small patch would be required
>>>     to the driver working correctly in interrupt mode with PEC.
>>>  3) It has not been tested in SMBus Slave mode.
>>>  4) It has not been tested with SMI#-type interrupts.
>>>  5) The BIOS has to configure the PCH SMBus IRQ properly.
>>>  6) It has not been tested with a device that does byte-by-byte smbus (non-i2c)
>>>     reads.
>> I think I can test this.
>>>  7) It has not been tested with smbus 'process call' transactions.
>> But not this.
>>> If would be very helpful if somebody could help test on other chipsets, with
>>> a PEC device, or on additional BIOS that woudl be very helpful.
>> I will do what I can with the hardware I have here.
> Jean,
> Ping?
>>> In the meantime, the interrupt behavior is only enabled on the Cougar Point,
>>> and even here, it can be completely disabled with the "Interrupt" feature like
>>> other advanced features of the driver.
>>> Daniel Kurtz (3):
>>>   i2c: i801: refactor i801_block_transaction_byte_by_byte
>>>   i2c: i801: enable irq for i801 smbus transactions
>>>   i2c: i801: enable irq for byte_by_byte transactions
>>>  drivers/i2c/busses/i2c-i801.c |  199 ++++++++++++++++++++++++++++++++++++-----
>>>  1 files changed, 175 insertions(+), 24 deletions(-)
>> --
>> Jean Delvare
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at