diff options
| author | Dong Aisheng <b29396@freescale.com> | 2013-10-21 04:54:40 -0400 |
|---|---|---|
| committer | Nitin Garg <nitin.garg@freescale.com> | 2014-04-16 09:05:50 -0400 |
| commit | 384cefbb3f6605f92aa6fb008320f57f7eb07d20 (patch) | |
| tree | 501ef81ed1d25f18cd67647a1dc661c7d065cbd2 /include/linux/platform_data | |
| parent | 6bb4a50d9b60d4787d1e116a84c5994291eb2872 (diff) | |
mmc: sdhci-esdhc-imx: add delay line setting support
The DLL(Delay Line) is newly added to assist in sampling read data.
The DLL provides the ability to programmatically select a quantized
delay (in fractions of the clock period) regardless of on-chip variations
such as process, voltage and temperature (PVT).
This patch adds a user interface to set slave delay line via device tree.
It's usually used in high speed mode like mmc DDR mode when the signal
quality is not good caused by board design, e.g. the signal path is too
long. User can manually set delay line to find a suitable data sampling
window for card to work properly.
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
Diffstat (limited to 'include/linux/platform_data')
| -rw-r--r-- | include/linux/platform_data/mmc-esdhc-imx.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/platform_data/mmc-esdhc-imx.h b/include/linux/platform_data/mmc-esdhc-imx.h index 4bcb73d57c69..e1571efa3f2b 100644 --- a/include/linux/platform_data/mmc-esdhc-imx.h +++ b/include/linux/platform_data/mmc-esdhc-imx.h | |||
| @@ -44,5 +44,6 @@ struct esdhc_platform_data { | |||
| 44 | enum cd_types cd_type; | 44 | enum cd_types cd_type; |
| 45 | int max_bus_width; | 45 | int max_bus_width; |
| 46 | bool support_vsel; | 46 | bool support_vsel; |
| 47 | unsigned int delay_line; | ||
| 47 | }; | 48 | }; |
| 48 | #endif /* __ASM_ARCH_IMX_ESDHC_H */ | 49 | #endif /* __ASM_ARCH_IMX_ESDHC_H */ |