Re: [PATCH v11 0/4] AT91: replace old i2c-at91.c TWI driver

[ludovic.desroches <ludovic.desroches@atmel.com>]

Hi Nikolaus,

Le 08/29/2012 09:28 AM, Nikolaus Voss a écrit :
> The old driver has two main deficencies:
> i)  No repeated start (Sr) condiction is possible, this makes it unusable
>      e.g. for most SMBus transfers.
> ii) I/O was done with polling/busy waiting what caused over-/underruns
>      even at light system loads and clock speeds.
>
> The new driver overcomes these deficencies and in addition allows for
> more than one TWI interface.
>
> A remaining limitation is the fact, that only one repeated start is
> possible (two concatenated messages). This limitation is imposed by
> the hardware. However, this should not be a problem as all common
> i2c-client communication does not rely on more than one repeated start.
>
> Changes since v11:
> - corrected wrong id_entry on sam9261 twi gpio pdev
>

Thanks for this new version, you can add
Tested-By: Ludovic Desroches <ludovic.desroches@atmel.com>
for the whole series.

Concerning the open drain issue, even if I don't have it on my board 
your patch is correct it is needed also for chips. Once I'll have the 
complete list, I'll send an additional patch.

Regards

Ludovic


> Nikolaus Voss (4):
>    drivers/i2c/busses/i2c-at91.c: remove old polling driver
>    Replace clk_lookup.con_id with clk_lookup.dev_id entries for twi clk
>    drivers/i2c/busses/i2c-at91.c: add new driver
>    G45 TWI: remove open drain setting for twi function gpios
>
>   arch/arm/mach-at91/at91rm9200.c            |    1 +
>   arch/arm/mach-at91/at91rm9200_devices.c    |    9 +
>   arch/arm/mach-at91/at91sam9260.c           |    1 +
>   arch/arm/mach-at91/at91sam9261.c           |    1 +
>   arch/arm/mach-at91/at91sam9261_devices.c   |    9 +
>   arch/arm/mach-at91/at91sam9263.c           |    1 +
>   arch/arm/mach-at91/at91sam9g45.c           |    2 +
>   arch/arm/mach-at91/at91sam9g45_devices.c   |    6 -
>   arch/arm/mach-at91/at91sam9rl.c            |    2 +
>   arch/arm/mach-at91/at91sam9x5.c            |    3 +
>   arch/arm/mach-at91/include/mach/at91_twi.h |   68 ----
>   drivers/i2c/busses/Kconfig                 |   11 +-
>   drivers/i2c/busses/i2c-at91.c              |  591 ++++++++++++++++++----------
>   13 files changed, 418 insertions(+), 287 deletions(-)
>   delete mode 100644 arch/arm/mach-at91/include/mach/at91_twi.h
>