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| author | Adrian Hunter <adrian.hunter@intel.com> | 2017-04-20 16:14:43 +0800 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2017-04-24 21:42:27 +0200 |
| commit | 83b600b8de0e83661a8f40091a7966fac052a21b (patch) | |
| tree | 4a4763e27e7814c3693c0449a9b8517def13c2da /drivers/mmc/host/sdhci.c | |
| parent | ba49cbd0936e12eac245c0fb420a291e8505f639 (diff) | |
| download | linux-83b600b8de0e83661a8f40091a7966fac052a21b.tar.gz linux-83b600b8de0e83661a8f40091a7966fac052a21b.tar.bz2 linux-83b600b8de0e83661a8f40091a7966fac052a21b.zip | |
mmc: sdhci: Control the delay between tuning commands
The delay between tuning commands for SD cards is not part of the
specification. A driver that needs it probably needs it for eMMC
too, whereas most drivers would probably like to set it to 0. Make
it a host member (host->tuning_delay) that defaults to the existing
behaviour. Drivers can set it to zero to eliminate the delay, or
set it to a positive value to always have a delay.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc/host/sdhci.c')
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 4bdad8959ec2..ecd0d4350e8a 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2108,9 +2108,9 @@ static void __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode) break; } - /* eMMC spec does not require a delay between tuning cycles */ - if (opcode == MMC_SEND_TUNING_BLOCK) - mdelay(1); + /* Spec does not require a delay between tuning cycles */ + if (host->tuning_delay > 0) + mdelay(host->tuning_delay); } pr_info("%s: Tuning failed, falling back to fixed sampling clock\n", @@ -2172,6 +2172,9 @@ int sdhci_execute_tuning(struct mmc_host *mmc, u32 opcode) host->mmc->retune_period = tuning_count; + if (host->tuning_delay < 0) + host->tuning_delay = opcode == MMC_SEND_TUNING_BLOCK; + sdhci_start_tuning(host); __sdhci_execute_tuning(host, opcode); @@ -3114,6 +3117,8 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev, host->cqe_ier = SDHCI_CQE_INT_MASK; host->cqe_err_ier = SDHCI_CQE_INT_ERR_MASK; + host->tuning_delay = -1; + return host; } |