From: Nikolaus Voss <n.voss@weinmann.de>
To: linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org
Cc: nicolas.ferre@atmel.com, ben-linux@fluff.org, balbi@ti.com,
h.feurstein@gmail.com, rmallon@gmail.com, adrian.yanes@aalto.fi
Subject: [PATCH v10 0/4] AT91: replace broken TWI driver i2c-at91.c
Date: Fri, 20 Apr 2012 12:13:30 +0200 [thread overview]
Message-ID: <cover.1334916810.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.
Signed-off-by: Nikolaus Voss <n.voss@weinmann.de>
Reviewed-by: Felipe Balbi <balbi@ti.com>
Tested-by: Hubert Feurstein <h.feurstein@gmail.com>
v10: - applied fix for RXRDY overrun bug submitted by Hubert Feurstein
- applied fix for calculating twi_clk
v9: - merge i2c-at91.c patches to single patch
- rewrite cwgr reg after timeout
v8: - remove local include
- remove cpu_is_rm9200() and put twi hw bug info in platform_device
- use readl/writel_relaxed instead of __raw_readl/writel
v7: i) fix bug if internal address > 1 byte
ii) send stop when len == 1 (both reported by Carsten Behling)
v6: 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 (4):
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
arch/arm/mach-at91/at91cap9.c | 1 +
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/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 | 579 ++++++++++++++++++----------
12 files changed, 393 insertions(+), 289 deletions(-)
delete mode 100644 arch/arm/mach-at91/include/mach/at91_twi.h
--
1.7.5.4
next reply other threads:[~2012-04-20 10:13 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-20 10:13 Nikolaus Voss [this message]
2011-11-08 10:49 ` [PATCH v10 1/4] drivers/i2c/busses/i2c-at91.c: remove broken driver Nikolaus Voss
2011-11-08 10:49 ` [PATCH v10 3/4] drivers/i2c/busses/i2c-at91.c: add new driver Nikolaus Voss
[not found] ` <cover.1334916810.git.n.voss-+umVssTZoCsb1SvskN2V4Q@public.gmane.org>
2011-11-08 11:09 ` [PATCH v10 2/4] Replace clk_lookup.con_id with clk_lookup.dev_id entries for twi clk Nikolaus Voss
2011-11-08 11:11 ` [PATCH v10 4/4] G45 TWI: remove open drain setting for twi function gpios Nikolaus Voss
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