From 6e8201f57c9359c9c5dc8f9805c15a4392492a10 Mon Sep 17 00:00:00 2001 From: Jaehoon Chung Date: Mon, 16 Jan 2012 17:49:01 +0900 Subject: 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 Signed-off-by: Kyungmin Park Acked-by: Adrian Hunter Signed-off-by: Chris Ball --- drivers/mmc/core/core.c | 4 ++++ include/linux/mmc/host.h | 1 + 2 files changed, 5 insertions(+) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index b3063b741df3..18661554e79c 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1131,6 +1131,10 @@ int mmc_regulator_set_ocr(struct mmc_host *mmc, * might not allow this operation */ voltage = regulator_get_voltage(supply); + + if (mmc->caps2 & MMC_CAP2_BROKEN_VOLTAGE) + min_uV = max_uV = voltage; + if (voltage < 0) result = voltage; else if (voltage < min_uV || voltage > max_uV) diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 73e5ee8e9ca2..ee2b0363c040 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -257,6 +257,7 @@ struct mmc_host { #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; -- cgit v1.2.3