4.14-stable review patch. If anyone has any objections, please let me know.
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From: Stefan Agner stefan@agner.ch
[ Upstream commit 1b5190c2e74c47ebe4bcecf7a072358ad9f1feaa ]
For eMMC devices it is valid to only support 1.8V signaling. When vqmmc is set to a fixed 1.8V regulator the stack tries to set 3.3V initially and prints the following warning: mmc1: Switching to 3.3V signalling voltage failed
Clear the MMC_SIGNAL_VOLTAGE_330 flag in case 3.3V is signaling is not available. This prevents the stack from even trying to use 3.3V signaling and avoids the above warning.
Signed-off-by: Stefan Agner stefan@agner.ch 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.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -3631,14 +3631,21 @@ int sdhci_setup_host(struct sdhci_host * mmc_gpio_get_cd(host->mmc) < 0) mmc->caps |= MMC_CAP_NEEDS_POLL;
- /* If vqmmc regulator and no 1.8V signalling, then there's no UHS */ if (!IS_ERR(mmc->supply.vqmmc)) { ret = regulator_enable(mmc->supply.vqmmc); + + /* If vqmmc provides no 1.8V signalling, then there's no UHS */ if (!regulator_is_supported_voltage(mmc->supply.vqmmc, 1700000, 1950000)) host->caps1 &= ~(SDHCI_SUPPORT_SDR104 | SDHCI_SUPPORT_SDR50 | SDHCI_SUPPORT_DDR50); + + /* In eMMC case vqmmc might be a fixed 1.8V regulator */ + if (!regulator_is_supported_voltage(mmc->supply.vqmmc, 2700000, + 3600000)) + host->flags &= ~SDHCI_SIGNALING_330; + if (ret) { pr_warn("%s: Failed to enable vqmmc regulator: %d\n", mmc_hostname(mmc), ret);