Commit Graph

3 Commits

Author SHA1 Message Date
Stephen Warren
68049a082b i2c: tegra: use repeated start for reads
I2C read transactions are typically implemented as follows:

START(write) address REPEATED_START(read) data... STOP

However, Tegra's I2C driver currently implements reads as follows:

START(write) address STOP START(read) data... STOP

This sequence confuses at least the AS3722 PMIC on the Jetson TK1 board,
leading to corrupted read data in some cases. Fix the driver to chain
the transactions together using repeated starts to solve this.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Yen Lin <yelin@nvidia.com>
2014-07-03 06:29:19 +02:00
Tom Warren
e32624ef82 Tegra: I2C: Add T114 clock support to tegra_i2c driver
T114 has a slightly different I2C clock, with a new (extra) divisor
in standard/fast mode and HS mode. Tested on my Dalmore, and the I2C
clock is 100KHz +/- 3Hz on my Saleae Logic analyzer.

Added a new entry in compat_names for T114 I2C since it differs
from the previous Tegra SoCs. A flag is set when T114 I2C HW is
found so new features like the extra clock divisor can be used.

Signed-off-by: Tom Warren <twarren@nvidia.com>
Acked-by: Laxman Dewangan <ldewangan@nvidia.com>
2013-03-14 11:06:41 -07:00
Tom Warren
150c24936b Tegra20: Move some include files to arch-tegra for sharing with Tegra30
The move is pretty straight-forward. ap20.h and tegra20.h were renamed to ap.h and tegra.h.
Some files remain in arch-tegra20 but 'include' a file in 'arch-tegra' with #defines & structs
that will be common between T20 and T30 HW. HW-specific #defines, etc. stay in the 'arch-tegra20'
'root' file.

All boards build OK w/MAKEALL -s tegra20. Checkpatch.pl runs clean. Seaboard works OK.

Signed-off-by: Tom Warren <twarren@nvidia.com>
2012-10-15 11:54:06 -07:00