[PATCH v8 0/7] AT91: replace broken TWI driver i2c-at91.c

From: Nikolaus Voss
Date: Mon Nov 28 2011 - 06:43:55 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.

v8: Patch 6/7: remove local include
Patch 7/7: remove cpu_is_rm9200() and put twi hw bug info
in platform_device
Patch 3/7: use readl/writel_relaxed instead of __raw_readl/writel
v7: Patch 4/5: i) fix bug if internal address > 1 byte
ii) send stop when len == 1
(both reported by Carsten Behling)
v6: Patch 5/5: support for I2C_SMBUS_BLOCK_DATA transfers.
Better use of clk_(un)prepare().
More sensible transfer timeout.
v5: Another round of review comments from Ryan Mallon, Felipe Balbi
and Russell King: convert twi clk to use .dev_id, cleanups
v4: Integrated more review comments from Ryan Mallon and Felipe Balbi:
Moved register include file to local include, code cleanups
v3: Integrated review comments from Ryan Mallon and Felipe Balbi
v2: Fixed whitespace issue

Nikolaus Voss (7):
drivers/i2c/busses/i2c-at91.c: remove broken 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
i2c-at91.c: add SMBUS_READ_BLOCK_DATA functionality
i2c-at91: removed local include
i2c-at91: make ckdiv bug a property of the platform_device

arch/arm/mach-at91/at91cap9.c | 1 +
arch/arm/mach-at91/at91cap9_devices.c | 9 +
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/at91sam9260_devices.c | 9 +
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/at91sam9263_devices.c | 9 +
arch/arm/mach-at91/at91sam9g45.c | 2 +
arch/arm/mach-at91/at91sam9g45_devices.c | 16 +-
arch/arm/mach-at91/at91sam9rl.c | 2 +
arch/arm/mach-at91/at91sam9rl_devices.c | 9 +
arch/arm/mach-at91/include/mach/at91_twi.h | 68 ----
drivers/i2c/busses/Kconfig | 11 +-
drivers/i2c/busses/i2c-at91.c | 563 +++++++++++++++++-----------
17 files changed, 424 insertions(+), 297 deletions(-)
delete mode 100644 arch/arm/mach-at91/include/mach/at91_twi.h

--
1.7.5.4

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