]> git.baikalelectronics.ru Git - kernel.git/commit
mmc: sdhci-msm: Add calibration tuning for CDCLP533 circuit
authorRitesh Harjani <riteshh@codeaurora.org>
Mon, 21 Nov 2016 06:37:25 +0000 (12:07 +0530)
committerUlf Hansson <ulf.hansson@linaro.org>
Tue, 29 Nov 2016 08:05:19 +0000 (09:05 +0100)
commite4a409d09c1164728ab675413b96a9efd05cc088
tree3235f14994d12f82baed1cdaa418412576174809
parent691e1885f9bc6f468d3581898e3e5457c1ea4034
mmc: sdhci-msm: Add calibration tuning for CDCLP533 circuit

In HS400 mode a new RCLK is introduced on the interface for read data
transfers. The eMMC5.0 device transmits the read data to the host with
respect to rising and falling edges of RCLK. In order to ensure correct
operation of read data transfers in HS400 mode, the incoming RX data
needs to be sampled by delayed version of RCLK.

The CDCLP533 delay circuit shifts the RCLK by T/4. It needs to be
initialized, configured and enabled once during HS400 mode switch and
when operational voltage/clock is changed.

Signed-off-by: Venkat Gopalakrishnan <venkatg@codeaurora.org>
Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/host/sdhci-msm.c