mmc: core: add the capability for broken voltage
There is an understood mismatch between the voltage the host controller is
set to and the voltage supplied to the card by a fixed voltage regulator.
Teaching the driver to accept the mismatch is overly complicated. Instead
just accept the regulator's voltage.
This patch adds MMC_CAP2_BROKEN_VOLTAGE.
If the voltage didn't satisfy between min_uV and max_uV, try to change
the voltage in core.c. When changing the voltage, maybe use
regulator_set_voltage().
In regulator_set_voltage(), check the below condition.
/* sanity check */
if (!rdev->desc->ops->set_voltage &&
!rdev->desc->ops->set_voltage_sel) {
ret = -EINVAL;
goto out;
}
If some board should use the fixed-regulator, always return -EINVAL.
Then, eMMC didn't initialize always.
So if use a fixed-regulator, we need to add the MMC_CAP2_BROKEN_VOLTAGE.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 73e5ee8..ee2b036 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -257,6 +257,7 @@
#define MMC_CAP2_HS200_1_2V_SDR (1 << 6) /* can support */
#define MMC_CAP2_HS200 (MMC_CAP2_HS200_1_8V_SDR | \
MMC_CAP2_HS200_1_2V_SDR)
+#define MMC_CAP2_BROKEN_VOLTAGE (1 << 7) /* Use the broken voltage */
mmc_pm_flag_t pm_caps; /* supported pm features */
unsigned int power_notify_type;