We should use current channel 'status' bits to clear DP aux channel's
done and error bits, instead of using the channel setting bits, that
will set send/busy bit again to initiate new transaction.
This also includes also some minor cleanup.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Convert many printk calls to DRM_DEBUG calls to reduce kernel log noise
for normal activities. Switch other printk calls to DRM_ERROR or DRM_INFO.
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
The display port aux channel clock is taken from the hrawclk value, which is
provided to the chip as the FSB frequency (as far as I can determine). The
strapping values for that are available in the CLKCFG register, now used to
select an appropriate divider to generate a 2MHz clock.
In addition, the DisplayPort spec requires that each aux channel I/O be
retried 'at least 3 times' in case the sink is idle when the first request
comes in.
Signed-off-by: Keith Packard <keithp@keithp.com>