| From foo@baz Thu Mar 22 14:57:32 CET 2018 |
| From: yangbo lu <yangbo.lu@nxp.com> |
| Date: Thu, 20 Apr 2017 14:58:29 +0800 |
| Subject: mmc: sdhci-of-esdhc: limit SD clock for ls1012a/ls1046a |
| |
| From: yangbo lu <yangbo.lu@nxp.com> |
| |
| |
| [ Upstream commit a627f025eb0534052ff451427c16750b3530634c ] |
| |
| The ls1046a datasheet specified that the max SD clock frequency |
| for eSDHC SDR104/HS200 was 167MHz, and the ls1012a datasheet |
| specified it's 125MHz for ls1012a. So this patch is to add the |
| limitation. |
| |
| Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com> |
| Acked-by: Adrian Hunter <adrian.hunter@intel.com> |
| Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> |
| Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/mmc/host/sdhci-of-esdhc.c | 14 ++++++++++++++ |
| 1 file changed, 14 insertions(+) |
| |
| --- a/drivers/mmc/host/sdhci-of-esdhc.c |
| +++ b/drivers/mmc/host/sdhci-of-esdhc.c |
| @@ -418,6 +418,20 @@ static void esdhc_of_set_clock(struct sd |
| if (esdhc->vendor_ver < VENDOR_V_23) |
| pre_div = 2; |
| |
| + /* |
| + * Limit SD clock to 167MHz for ls1046a according to its datasheet |
| + */ |
| + if (clock > 167000000 && |
| + of_find_compatible_node(NULL, NULL, "fsl,ls1046a-esdhc")) |
| + clock = 167000000; |
| + |
| + /* |
| + * Limit SD clock to 125MHz for ls1012a according to its datasheet |
| + */ |
| + if (clock > 125000000 && |
| + of_find_compatible_node(NULL, NULL, "fsl,ls1012a-esdhc")) |
| + clock = 125000000; |
| + |
| /* Workaround to reduce the clock frequency for p1010 esdhc */ |
| if (of_find_compatible_node(NULL, NULL, "fsl,p1010-esdhc")) { |
| if (clock > 20000000) |
