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

From: Nikolaus Voss
Date: Wed Aug 22 2012 - 03:36:52 EST


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 v10:
- fix for flags persistency suggested and tested by Carsten Behling
- clk_lookup.dev_id entries for at91sam9x5
- calc_twi_clock fix for sam9261 by Ludovic Desroches

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

--
1.7.9.5

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