[PATCH 4/5] mmc: sdhci: Don't try to switch to unsupported voltage

From: Shawn Lin
Date: Tue Sep 20 2016 - 21:43:48 EST


From: Ziyuan Xu <xzy.xu@xxxxxxxxxxxxxx>

Sdhci shouldn't switch to the unsupported voltage if claiming
that it can not support the requested voltage. Let's fix it.

Signed-off-by: Ziyuan Xu <xzy.xu@xxxxxxxxxxxxxx>
Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
---

drivers/mmc/host/sdhci.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 4805566..b1f1edd 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1845,7 +1845,8 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,

switch (ios->signal_voltage) {
case MMC_SIGNAL_VOLTAGE_330:
- if (!(host->flags & SDHCI_SIGNALING_330))
+ if (!(host->flags & SDHCI_SIGNALING_330) ||
+ !(host->caps & SDHCI_CAN_VDD_330))
return -EINVAL;
/* Set 1.8V Signal Enable in the Host Control2 register to 0 */
ctrl &= ~SDHCI_CTRL_VDD_180;
@@ -1872,7 +1873,8 @@ static int sdhci_start_signal_voltage_switch(struct mmc_host *mmc,

return -EAGAIN;
case MMC_SIGNAL_VOLTAGE_180:
- if (!(host->flags & SDHCI_SIGNALING_180))
+ if (!(host->flags & SDHCI_SIGNALING_180) ||
+ !(host->caps & SDHCI_CAN_VDD_180))
return -EINVAL;
if (!IS_ERR(mmc->supply.vqmmc)) {
ret = mmc_regulator_set_vqmmc(mmc, ios);
--
2.3.7