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| author | Arindam Nath <arindam.nath@amd.com> | 2011-05-05 12:19:02 +0530 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2011-05-24 23:53:45 -0400 |
| commit | 5371c927bcd06a5c9dd6785bab2d452b87d9abc6 (patch) | |
| tree | 71add97be08e93fcb5ac2bfcc44fc66d8f2b92df /drivers/mmc/host/sdhci.c | |
| parent | 49c468fcf878d2c86e31920cf54aa90c88418a66 (diff) | |
| download | kernel_samsung_smdk4412-5371c927bcd06a5c9dd6785bab2d452b87d9abc6.zip kernel_samsung_smdk4412-5371c927bcd06a5c9dd6785bab2d452b87d9abc6.tar.gz kernel_samsung_smdk4412-5371c927bcd06a5c9dd6785bab2d452b87d9abc6.tar.bz2 | |
mmc: sd: set current limit for uhs cards
We decide on the current limit to be set for the card based on the
Capability of Host Controller to provide current at 1.8V signalling,
and the maximum current limit of the card as indicated by CMD6
mode 0. We then set the current limit for the card using CMD6 mode 1.
As per the Physical Layer Spec v3.01, the current limit switch is
only applicable for SDR50, SDR104, and DDR50 bus speed modes. For
other UHS-I modes, we set the default current limit of 200mA.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc/host/sdhci.c')
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 8994493..2a15aad 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2216,6 +2216,16 @@ int sdhci_add_host(struct sdhci_host *host) if (max_current_180 > 150) mmc->caps |= MMC_CAP_SET_XPC_180; + + /* Maximum current capabilities of the host at 1.8V */ + if (max_current_180 >= 800) + mmc->caps |= MMC_CAP_MAX_CURRENT_800; + else if (max_current_180 >= 600) + mmc->caps |= MMC_CAP_MAX_CURRENT_600; + else if (max_current_180 >= 400) + mmc->caps |= MMC_CAP_MAX_CURRENT_400; + else + mmc->caps |= MMC_CAP_MAX_CURRENT_200; } mmc->ocr_avail = ocr_avail; |