From: Nikolaus Voss <n.voss-+umVssTZoCsb1SvskN2V4Q@public.gmane.org>
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org
Subject: [PATCH v6 0/5] AT91: replace broken TWI driver i2c-at91.c
Date: Fri, 18 Nov 2011 12:46:27 +0100 [thread overview]
Message-ID: <cover.1321616787.git.n.voss@weinmann.de> (raw)
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.
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 (5):
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
arch/arm/mach-at91/at91cap9.c | 1 +
arch/arm/mach-at91/at91rm9200.c | 1 +
arch/arm/mach-at91/at91sam9260.c | 1 +
arch/arm/mach-at91/at91sam9261.c | 1 +
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/include/mach/at91_twi.h | 68 ----
drivers/i2c/busses/Kconfig | 11 +-
drivers/i2c/busses/i2c-at91.c | 527 +++++++++++++++++-----------
drivers/i2c/busses/i2c-at91.h | 80 +++++
12 files changed, 406 insertions(+), 295 deletions(-)
delete mode 100644 arch/arm/mach-at91/include/mach/at91_twi.h
create mode 100644 drivers/i2c/busses/i2c-at91.h
--
1.7.5.4
next reply other threads:[~2011-11-18 11:46 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-11-18 11:46 Nikolaus Voss [this message]
[not found] ` <cover.1321616787.git.n.voss-+umVssTZoCsb1SvskN2V4Q@public.gmane.org>
2011-11-08 10:49 ` [PATCH v6 1/5] drivers/i2c/busses/i2c-at91.c: remove broken driver Nikolaus Voss
2011-11-08 10:49 ` [PATCH v6 3/5] drivers/i2c/busses/i2c-at91.c: add new driver Nikolaus Voss
2011-11-08 11:09 ` [PATCH v6 2/5] Replace clk_lookup.con_id with clk_lookup.dev_id entries for twi clk Nikolaus Voss
2011-11-08 11:11 ` [PATCH v6 4/5] G45 TWI: remove open drain setting for twi function gpios Nikolaus Voss
2011-11-18 11:38 ` [PATCH v6 5/5] i2c-at91.c: add SMBUS_READ_BLOCK_DATA functionality Nikolaus Voss
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