Commit 52221610 authored by Tim Kryger's avatar Tim Kryger Committed by Ulf Hansson

mmc: sdhci: Improve external VDD regulator support

A standard compliant SDHCI can itself supply VDD at 1.8, 3.0, or 3.3v.
Several vendors ignore this and instead rely upon external regulators
to supply VDD.  While the external regulators typically can supply one
of the standard SDHCI voltage levels, there is no real reason for this
to be a hard requirement.

This patch alters the SDHCI driver such that external VDD regulators
that provide voltages other than the three mentioned above may be used
so long as they can supply a voltage that meets the needs of the card.

In the case that an external VDD regulator is provided, it is reasonable
to ignore the voltage capabilities of the host controller and allow the
external regulator to set the OCR mask.  Additionally, there is no need
to convert a VDD voltage request into one of the standard SDHCI voltage
levels or program it in the host controller's power control register.
Signed-off-by: default avatarTim Kryger <tim.kryger@gmail.com>
Tested-by: default avatarSachin Kamat <spk.linux@gmail.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 87a0f46a
...@@ -1226,6 +1226,13 @@ static void sdhci_set_power(struct sdhci_host *host, unsigned char mode, ...@@ -1226,6 +1226,13 @@ static void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
struct mmc_host *mmc = host->mmc; struct mmc_host *mmc = host->mmc;
u8 pwr = 0; u8 pwr = 0;
if (!IS_ERR(mmc->supply.vmmc)) {
spin_unlock_irq(&host->lock);
mmc_regulator_set_ocr(host->mmc, mmc->supply.vmmc, vdd);
spin_lock_irq(&host->lock);
return;
}
if (mode != MMC_POWER_OFF) { if (mode != MMC_POWER_OFF) {
switch (1 << vdd) { switch (1 << vdd) {
case MMC_VDD_165_195: case MMC_VDD_165_195:
...@@ -1284,12 +1291,6 @@ static void sdhci_set_power(struct sdhci_host *host, unsigned char mode, ...@@ -1284,12 +1291,6 @@ static void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
if (host->quirks & SDHCI_QUIRK_DELAY_AFTER_POWER) if (host->quirks & SDHCI_QUIRK_DELAY_AFTER_POWER)
mdelay(10); mdelay(10);
} }
if (!IS_ERR(mmc->supply.vmmc)) {
spin_unlock_irq(&host->lock);
mmc_regulator_set_ocr(host->mmc, mmc->supply.vmmc, vdd);
spin_lock_irq(&host->lock);
}
} }
/*****************************************************************************\ /*****************************************************************************\
...@@ -3092,8 +3093,9 @@ int sdhci_add_host(struct sdhci_host *host) ...@@ -3092,8 +3093,9 @@ int sdhci_add_host(struct sdhci_host *host)
SDHCI_MAX_CURRENT_MULTIPLIER; SDHCI_MAX_CURRENT_MULTIPLIER;
} }
/* If OCR set by external regulators, use it instead */
if (mmc->ocr_avail) if (mmc->ocr_avail)
ocr_avail &= mmc->ocr_avail; ocr_avail = mmc->ocr_avail;
if (host->ocr_mask) if (host->ocr_mask)
ocr_avail &= host->ocr_mask; ocr_avail &= host->ocr_mask;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment