From: ludovic.desroches@atmel•com (ludovic.desroches)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v11 0/4] AT91: replace old i2c-at91.c TWI driver
Date: Wed, 29 Aug 2012 14:06:10 +0200 [thread overview]
Message-ID: <503E05B2.2020204@atmel.com> (raw)
In-Reply-To: <cover.1346225321.git.n.voss@weinmann.de>
Hi Nikolaus,
Le 08/29/2012 09:28 AM, Nikolaus Voss a ?crit :
> 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
>
next parent reply other threads:[~2012-08-29 12:06 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <cover.1346225321.git.n.voss@weinmann.de>
2012-08-29 12:06 ` ludovic.desroches [this message]
2012-09-12 7:59 ` [PATCH v11 0/4] AT91: replace old i2c-at91.c TWI driver Nicolas Ferre
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