u-boot/drivers/i2c
Nick Thompson 0e57968a21 I2C: OMAP: detect more devices when probing an i2c bus
The omap24xx driver only seems to support devices that have a single subaddress
byte. With these types of devices, the first access in a bus transaction is
usually a write (writes the subaddress) followed by either a read or write to
access the devices registers.

Many such devices will respond to a read as the first access, but there are at
least some that will NACK such a read. (e.g. ADV7180.)

The probe function attempts to detect a devices ACK to a read access only and
fails to find devices that NACK a read.

This commit modifies the probe function to start a write instead. This detects
devices that respond to reads (since they must also respond to writes) as well
as those that only respond to writes. The bus is immediately set to idle after a
(N)ACK avoiding actually writing anything to the device.

Signed-off-by: Nick Thompson <nick.thompson@ge.com>
2011-04-14 08:33:23 +02:00
..
bfin-twi_i2c.c Blackfin: TWI/I2C: implement multibus support 2010-05-05 10:04:38 +02:00
davinci_i2c.c davinci: move i2c driver to drivers/i2c 2009-03-30 18:58:39 +02:00
fsl_i2c.c fsl_i2c: Added a callpoint for i2c_board_late_init 2010-04-19 07:46:35 +02:00
Makefile Switch from archive libraries to partial linking 2010-11-17 21:02:18 +01:00
mvtwsi.c i2c: rewrite mvtwsi, support orion5x and kirkwood 2010-08-30 14:10:35 +02:00
mxc_i2c.c I2C: mxc_i2c: address failure with mx35 processor 2011-02-02 00:54:43 +01:00
omap24xx_i2c.c I2C: OMAP: detect more devices when probing an i2c bus 2011-04-14 08:33:23 +02:00
omap24xx_i2c.h i2c: omap2+: change header guard to be generic 2010-08-23 08:08:31 +02:00
omap1510_i2c.c Cleanup: fix "MHz" spelling 2008-10-21 11:25:39 +02:00
pca9564_i2c.c new PCA9564 i2c bridge driver 2009-10-30 15:10:58 +01:00
ppc4xx_i2c.c ppc4xx: Move ppc4xx headers to powerpc include directory 2010-09-23 09:02:05 +02:00
s3c24x0_i2c.c Add generic support for samsung s3c2440 2010-10-28 15:35:56 +09:00
s3c44b0_i2c.c s3c44b0: move i2c driver to drivers/i2c 2009-03-29 23:01:40 +02:00
soft_i2c.c Fix at91 includes in soft_i2c driver 2011-01-27 07:27:32 +01:00
spr_i2c.c mod change 755 => 644 for multiple files 2010-03-21 22:22:53 +01:00
tsi108_i2c.c i2c: Update references to individual i2c commands 2009-06-12 20:39:46 +02:00