[lkml]   [2011]   [Nov]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subject[PATCH v7 0/5] AT91: replace broken TWI driver i2c-at91.c
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.

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 (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 | 529 +++++++++++++++++-----------
drivers/i2c/busses/i2c-at91.h | 80 +++++
12 files changed, 408 insertions(+), 295 deletions(-)
delete mode 100644 arch/arm/mach-at91/include/mach/at91_twi.h
create mode 100644 drivers/i2c/busses/i2c-at91.h


 \ /
  Last update: 2011-11-23 17:01    [W:0.284 / U:0.780 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site