mirror of https://gitee.com/openkylin/linux.git
261 lines
7.1 KiB
C
261 lines
7.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Helper functions for MMC regulators.
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/log2.h>
|
|
#include <linux/regulator/consumer.h>
|
|
|
|
#include <linux/mmc/host.h>
|
|
|
|
#include "core.h"
|
|
#include "host.h"
|
|
|
|
#ifdef CONFIG_REGULATOR
|
|
|
|
/**
|
|
* mmc_ocrbitnum_to_vdd - Convert a OCR bit number to its voltage
|
|
* @vdd_bit: OCR bit number
|
|
* @min_uV: minimum voltage value (mV)
|
|
* @max_uV: maximum voltage value (mV)
|
|
*
|
|
* This function returns the voltage range according to the provided OCR
|
|
* bit number. If conversion is not possible a negative errno value returned.
|
|
*/
|
|
static int mmc_ocrbitnum_to_vdd(int vdd_bit, int *min_uV, int *max_uV)
|
|
{
|
|
int tmp;
|
|
|
|
if (!vdd_bit)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* REVISIT mmc_vddrange_to_ocrmask() may have set some
|
|
* bits this regulator doesn't quite support ... don't
|
|
* be too picky, most cards and regulators are OK with
|
|
* a 0.1V range goof (it's a small error percentage).
|
|
*/
|
|
tmp = vdd_bit - ilog2(MMC_VDD_165_195);
|
|
if (tmp == 0) {
|
|
*min_uV = 1650 * 1000;
|
|
*max_uV = 1950 * 1000;
|
|
} else {
|
|
*min_uV = 1900 * 1000 + tmp * 100 * 1000;
|
|
*max_uV = *min_uV + 100 * 1000;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* mmc_regulator_get_ocrmask - return mask of supported voltages
|
|
* @supply: regulator to use
|
|
*
|
|
* This returns either a negative errno, or a mask of voltages that
|
|
* can be provided to MMC/SD/SDIO devices using the specified voltage
|
|
* regulator. This would normally be called before registering the
|
|
* MMC host adapter.
|
|
*/
|
|
static int mmc_regulator_get_ocrmask(struct regulator *supply)
|
|
{
|
|
int result = 0;
|
|
int count;
|
|
int i;
|
|
int vdd_uV;
|
|
int vdd_mV;
|
|
|
|
count = regulator_count_voltages(supply);
|
|
if (count < 0)
|
|
return count;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
vdd_uV = regulator_list_voltage(supply, i);
|
|
if (vdd_uV <= 0)
|
|
continue;
|
|
|
|
vdd_mV = vdd_uV / 1000;
|
|
result |= mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
|
|
}
|
|
|
|
if (!result) {
|
|
vdd_uV = regulator_get_voltage(supply);
|
|
if (vdd_uV <= 0)
|
|
return vdd_uV;
|
|
|
|
vdd_mV = vdd_uV / 1000;
|
|
result = mmc_vddrange_to_ocrmask(vdd_mV, vdd_mV);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* mmc_regulator_set_ocr - set regulator to match host->ios voltage
|
|
* @mmc: the host to regulate
|
|
* @supply: regulator to use
|
|
* @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
|
|
*
|
|
* Returns zero on success, else negative errno.
|
|
*
|
|
* MMC host drivers may use this to enable or disable a regulator using
|
|
* a particular supply voltage. This would normally be called from the
|
|
* set_ios() method.
|
|
*/
|
|
int mmc_regulator_set_ocr(struct mmc_host *mmc,
|
|
struct regulator *supply,
|
|
unsigned short vdd_bit)
|
|
{
|
|
int result = 0;
|
|
int min_uV, max_uV;
|
|
|
|
if (vdd_bit) {
|
|
mmc_ocrbitnum_to_vdd(vdd_bit, &min_uV, &max_uV);
|
|
|
|
result = regulator_set_voltage(supply, min_uV, max_uV);
|
|
if (result == 0 && !mmc->regulator_enabled) {
|
|
result = regulator_enable(supply);
|
|
if (!result)
|
|
mmc->regulator_enabled = true;
|
|
}
|
|
} else if (mmc->regulator_enabled) {
|
|
result = regulator_disable(supply);
|
|
if (result == 0)
|
|
mmc->regulator_enabled = false;
|
|
}
|
|
|
|
if (result)
|
|
dev_err(mmc_dev(mmc),
|
|
"could not set regulator OCR (%d)\n", result);
|
|
return result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(mmc_regulator_set_ocr);
|
|
|
|
static int mmc_regulator_set_voltage_if_supported(struct regulator *regulator,
|
|
int min_uV, int target_uV,
|
|
int max_uV)
|
|
{
|
|
/*
|
|
* Check if supported first to avoid errors since we may try several
|
|
* signal levels during power up and don't want to show errors.
|
|
*/
|
|
if (!regulator_is_supported_voltage(regulator, min_uV, max_uV))
|
|
return -EINVAL;
|
|
|
|
return regulator_set_voltage_triplet(regulator, min_uV, target_uV,
|
|
max_uV);
|
|
}
|
|
|
|
/**
|
|
* mmc_regulator_set_vqmmc - Set VQMMC as per the ios
|
|
*
|
|
* For 3.3V signaling, we try to match VQMMC to VMMC as closely as possible.
|
|
* That will match the behavior of old boards where VQMMC and VMMC were supplied
|
|
* by the same supply. The Bus Operating conditions for 3.3V signaling in the
|
|
* SD card spec also define VQMMC in terms of VMMC.
|
|
* If this is not possible we'll try the full 2.7-3.6V of the spec.
|
|
*
|
|
* For 1.2V and 1.8V signaling we'll try to get as close as possible to the
|
|
* requested voltage. This is definitely a good idea for UHS where there's a
|
|
* separate regulator on the card that's trying to make 1.8V and it's best if
|
|
* we match.
|
|
*
|
|
* This function is expected to be used by a controller's
|
|
* start_signal_voltage_switch() function.
|
|
*/
|
|
int mmc_regulator_set_vqmmc(struct mmc_host *mmc, struct mmc_ios *ios)
|
|
{
|
|
struct device *dev = mmc_dev(mmc);
|
|
int ret, volt, min_uV, max_uV;
|
|
|
|
/* If no vqmmc supply then we can't change the voltage */
|
|
if (IS_ERR(mmc->supply.vqmmc))
|
|
return -EINVAL;
|
|
|
|
switch (ios->signal_voltage) {
|
|
case MMC_SIGNAL_VOLTAGE_120:
|
|
return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
|
|
1100000, 1200000, 1300000);
|
|
case MMC_SIGNAL_VOLTAGE_180:
|
|
return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
|
|
1700000, 1800000, 1950000);
|
|
case MMC_SIGNAL_VOLTAGE_330:
|
|
ret = mmc_ocrbitnum_to_vdd(mmc->ios.vdd, &volt, &max_uV);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
dev_dbg(dev, "%s: found vmmc voltage range of %d-%duV\n",
|
|
__func__, volt, max_uV);
|
|
|
|
min_uV = max(volt - 300000, 2700000);
|
|
max_uV = min(max_uV + 200000, 3600000);
|
|
|
|
/*
|
|
* Due to a limitation in the current implementation of
|
|
* regulator_set_voltage_triplet() which is taking the lowest
|
|
* voltage possible if below the target, search for a suitable
|
|
* voltage in two steps and try to stay close to vmmc
|
|
* with a 0.3V tolerance at first.
|
|
*/
|
|
if (!mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
|
|
min_uV, volt, max_uV))
|
|
return 0;
|
|
|
|
return mmc_regulator_set_voltage_if_supported(mmc->supply.vqmmc,
|
|
2700000, volt, 3600000);
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(mmc_regulator_set_vqmmc);
|
|
|
|
#else
|
|
|
|
static inline int mmc_regulator_get_ocrmask(struct regulator *supply)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_REGULATOR */
|
|
|
|
/**
|
|
* mmc_regulator_get_supply - try to get VMMC and VQMMC regulators for a host
|
|
* @mmc: the host to regulate
|
|
*
|
|
* Returns 0 or errno. errno should be handled, it is either a critical error
|
|
* or -EPROBE_DEFER. 0 means no critical error but it does not mean all
|
|
* regulators have been found because they all are optional. If you require
|
|
* certain regulators, you need to check separately in your driver if they got
|
|
* populated after calling this function.
|
|
*/
|
|
int mmc_regulator_get_supply(struct mmc_host *mmc)
|
|
{
|
|
struct device *dev = mmc_dev(mmc);
|
|
int ret;
|
|
|
|
mmc->supply.vmmc = devm_regulator_get_optional(dev, "vmmc");
|
|
mmc->supply.vqmmc = devm_regulator_get_optional(dev, "vqmmc");
|
|
|
|
if (IS_ERR(mmc->supply.vmmc)) {
|
|
if (PTR_ERR(mmc->supply.vmmc) == -EPROBE_DEFER)
|
|
return -EPROBE_DEFER;
|
|
dev_dbg(dev, "No vmmc regulator found\n");
|
|
} else {
|
|
ret = mmc_regulator_get_ocrmask(mmc->supply.vmmc);
|
|
if (ret > 0)
|
|
mmc->ocr_avail = ret;
|
|
else
|
|
dev_warn(dev, "Failed getting OCR mask: %d\n", ret);
|
|
}
|
|
|
|
if (IS_ERR(mmc->supply.vqmmc)) {
|
|
if (PTR_ERR(mmc->supply.vqmmc) == -EPROBE_DEFER)
|
|
return -EPROBE_DEFER;
|
|
dev_dbg(dev, "No vqmmc regulator found\n");
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(mmc_regulator_get_supply);
|