sdhci: get rid of "frequency too high" flood when using eSDHC

Since commit 8dfd0374be84793360db7fff2e635d2cd3bbcb21 ("MMC core: limit
minimum initialization frequency to 400kHz") MMC core checks for minimum
frequency, and that causes following messages flood when using eSDHC
controllers:

  ...
  mmc0: Minimum clock frequency too high for identification mode
  mmc0: Minimum clock frequency too high for identification mode
  ...

The warnings are legitimate, since if we'd use 133 MHz clocks for standard
SDHCI controllers, we'd not able to scale frequency down to 400 kHz.

But eSDHC controllers have a non-standard SD clock management, so we can
divide clock by 256 * 16, not just 256.

This patch introduces get_min_clock() callback for sdhci core and
implements it for sdhci-of driver, and thus fixes the issue.

Signed-off-by: Anton Vorontsov <[email protected]>
Cc: Matt Fleming <[email protected]>
Cc: Ian Molton <[email protected]>
Cc: "Roberto A. Foglietta" <[email protected]>
Cc: Pierre Ossman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions