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| author | Haavard Skinnemoen <haavard.skinnemoen@atmel.com> | 2008-05-16 11:08:11 +0200 |
|---|---|---|
| committer | Wolfgang Denk <wd@denx.de> | 2008-06-03 20:25:56 +0200 |
| commit | 110e006fe67fb4a6e1719ae6956c79b7ffc0148b (patch) | |
| tree | 4263a5a7897272bf7a02bba37058f90e2ea742a4 /common | |
| parent | f979690ee337450b2030aba128f95b7a8d9881c0 (diff) | |
| download | u-boot-imx-110e006fe67fb4a6e1719ae6956c79b7ffc0148b.zip u-boot-imx-110e006fe67fb4a6e1719ae6956c79b7ffc0148b.tar.gz u-boot-imx-110e006fe67fb4a6e1719ae6956c79b7ffc0148b.tar.bz2 | |
soft_i2c: Pull SDA high before reading
Spotted by Dean Capindale.
Systems that support open-drain GPIO properly are allowed provide an
empty I2C_TRISTATE define. However, this means that we need to be
careful not to drive SDA low when the slave is expected to respond.
This patch adds a missing I2C_SDA(1) to read_byte() required to
tristate the SDA line on systems that support open-drain GPIO.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Diffstat (limited to 'common')
| -rw-r--r-- | common/soft_i2c.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/common/soft_i2c.c b/common/soft_i2c.c index c5d7e20..5ef7f30 100644 --- a/common/soft_i2c.c +++ b/common/soft_i2c.c @@ -252,6 +252,7 @@ static uchar read_byte(int ack) * Read 8 bits, MSB first. */ I2C_TRISTATE; + I2C_SDA(1); data = 0; for(j = 0; j < 8; j++) { I2C_SCL(0); |