Re: [PATCH] MMC: move regulator handling closer to core
From: Adrian Hunter
Date: Mon Aug 30 2010 - 17:04:37 EST
Linus Walleij wrote:
After discovering a problem in regulator reference counting I
took Mark Brown's advice to move the reference count into the
MMC core by making the regulator status a member of
struct mmc_host.
I took this opportunity to also implement NULL versions of
the regulator functions so as to rid the driver code from
some ugly #ifdef CONFIG_REGULATOR clauses.
Cc: Daniel Mack <daniel@xxxxxxxx>
Cc: Pierre Ossman <pierre@xxxxxxxxx>
Cc: Matt Fleming <matt@xxxxxxxxxxxxxxxxx>
Cc: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Cc: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
Cc: Eric Miao <eric.y.miao@xxxxxxxxx>
Cc: Cliff Brake <cbrake@xxxxxxxxxxxxxxx>
Cc: Jarkko Lavinen <jarkko.lavinen@xxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Liam Girdwood <lrg@xxxxxxxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
Cc: Tony Lindgren <tony@xxxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Robert Jarzmik <robert.jarzmik@xxxxxxx>
Cc: Sundar Iyer <sundar.iyer@xxxxxxxxxxxxxx>
Cc: Bengt Jonsson <bengt.jonsson@xxxxxxxxxxxxxx>
Cc: linux-mmc@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxxxxxx>
---
This is not the final movement of regulator code into the
MMC framework by a long shot, but it's atleast a starter.
If you like it, ACK it.
It's not easy for me to test this code since both the OMAP2 and
PXA3XX defconfigs have (unrelated) build failures on the current
-next tree, however the U300 builds fine and seems to work nicely,
I'll stress-test it a bit more though.
---
drivers/mmc/core/core.c | 38 +++++++++++++++++++++++++++++---------
drivers/mmc/host/mmci.c | 21 +++++++++++++--------
drivers/mmc/host/omap_hsmmc.c | 32 ++++++++++++++++++++++----------
drivers/mmc/host/pxamci.c | 24 ++++++++++++++++++------
include/linux/mmc/host.h | 8 +++++++-
5 files changed, 89 insertions(+), 34 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 5db49b1..1e8a70e 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -771,8 +771,9 @@ EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
/**
* mmc_regulator_set_ocr - set regulator to match host->ios voltage
- * @vdd_bit: zero for power off, else a bit number (host->ios.vdd)
+ * @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.
*
@@ -780,15 +781,12 @@ EXPORT_SYMBOL(mmc_regulator_get_ocrmask);
* a particular supply voltage. This would normally be called from the
* set_ios() method.
*/
-int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
+int mmc_regulator_set_ocr(struct mmc_host *mmc,
+ struct regulator *supply,
+ unsigned short vdd_bit)
{
int result = 0;
int min_uV, max_uV;
- int enabled;
-
- enabled = regulator_is_enabled(supply);
- if (enabled < 0)
- return enabled;
if (vdd_bit) {
int tmp;
@@ -819,16 +817,38 @@ int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit)
else
result = 0;
- if (result == 0 && !enabled)
+ if (result == 0 && !mmc->regulator_enabled) {
result = regulator_enable(supply);
- } else if (enabled) {
+ if (!result)
+ mmc->regulator_enabled = true;
+ }
+ } else if (mmc->regulator_enabled) {
result = regulator_disable(supply);
+ if (result == 0)
+ mmc->regulator_enabled = false;
}
return result;
}
EXPORT_SYMBOL(mmc_regulator_set_ocr);
+#else
+/*
+ * For drivers with optional regulator support we offer to
+ * just compile this thing out with functions that always
+ * succeed, just like the default stuff from the regulator
+ * core.
+ */
Shouldn't these be in the header? The comment is not needed.
+int inline mmc_regulator_get_ocrmask(struct regulator *supply)
+{
+ return 0;
+}
+int inline mmc_regulator_set_ocr(struct mmc_host *mmc,
+ struct regulator *supply,
+ unsigned short vdd_bit)
+{
+ return 0;
+}
#endif
/*
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 840b301..0734ccb 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -507,19 +507,24 @@ static void mmci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
struct mmci_host *host = mmc_priv(mmc);
u32 pwr = 0;
unsigned long flags;
+ int ret;
switch (ios->power_mode) {
case MMC_POWER_OFF:
- if(host->vcc &&
- regulator_is_enabled(host->vcc))
- regulator_disable(host->vcc);
+ if (host->vcc) {
+ ret = mmc_regulator_set_ocr(mmc, host->vcc, 0);
+ if (ret)
+ dev_err(mmc_dev(mmc),
+ "could not disable regulator\n");
What about putting the dev_err inside mmc_regulator_set_ocr()?
+ }
break;
case MMC_POWER_UP:
-#ifdef CONFIG_REGULATOR
- if (host->vcc)
- /* This implicitly enables the regulator */
- mmc_regulator_set_ocr(host->vcc, ios->vdd);
-#endif
+ if (host->vcc) {
+ ret = mmc_regulator_set_ocr(mmc, host->vcc, ios->vdd);
+ if (ret)
+ dev_err(mmc_dev(mmc),
+ "could not set regulator OCR\n");
+ }
if (host->plat->vdd_handler)
pwr |= host->plat->vdd_handler(mmc_dev(mmc), ios->vdd,
ios->power_mode);
diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 4a8776f..9debfe2 100644
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -249,10 +249,15 @@ static int omap_hsmmc_1_set_power(struct device *dev, int slot, int power_on,
if (mmc_slot(host).before_set_reg)
mmc_slot(host).before_set_reg(dev, slot, power_on, vdd);
- if (power_on)
- ret = mmc_regulator_set_ocr(host->vcc, vdd);
- else
- ret = mmc_regulator_set_ocr(host->vcc, 0);
+ if (power_on) {
+ ret = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
+ if (ret)
+ dev_err(dev, "could not set regulator OCR\n");
+ } else {
+ ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
+ if (ret)
+ dev_err(dev, "could not disable regulator\n");
+ }
if (mmc_slot(host).after_set_reg)
mmc_slot(host).after_set_reg(dev, slot, power_on, vdd);
@@ -291,18 +296,25 @@ static int omap_hsmmc_23_set_power(struct device *dev, int slot, int power_on,
* chips/cards need an interface voltage rail too.
*/
if (power_on) {
- ret = mmc_regulator_set_ocr(host->vcc, vdd);
+ ret = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
+ if (ret)
+ dev_err(dev, "could not set regulator OCR\n");
/* Enable interface voltage rail, if needed */
if (ret == 0 && host->vcc_aux) {
ret = regulator_enable(host->vcc_aux);
if (ret < 0)
- ret = mmc_regulator_set_ocr(host->vcc, 0);
+ ret = mmc_regulator_set_ocr(host->mmc,
+ host->vcc, 0);
}
} else {
+ /* Shut down the rail */
if (host->vcc_aux)
ret = regulator_disable(host->vcc_aux);
- if (ret == 0)
- ret = mmc_regulator_set_ocr(host->vcc, 0);
+ if (!ret) {
+ /* Then proceed to shut down the local regulator */
+ ret = mmc_regulator_set_ocr(host->mmc,
+ host->vcc, 0);
+ }
}
if (mmc_slot(host).after_set_reg)
@@ -343,9 +355,9 @@ static int omap_hsmmc_23_set_sleep(struct device *dev, int slot, int sleep,
if (cardsleep) {
/* VCC can be turned off if card is asleep */
if (sleep)
- err = mmc_regulator_set_ocr(host->vcc, 0);
+ err = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
else
- err = mmc_regulator_set_ocr(host->vcc, vdd);
+ err = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
} else
err = regulator_set_mode(host->vcc, mode);
if (err)
diff --git a/drivers/mmc/host/pxamci.c b/drivers/mmc/host/pxamci.c
index 0a4e43f..47dae9b 100644
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -99,14 +99,26 @@ static inline void pxamci_init_ocr(struct pxamci_host *host)
}
}
-static inline void pxamci_set_power(struct pxamci_host *host, unsigned int vdd)
+static inline void pxamci_set_power(struct pxamci_host *host,
+ unsigned char power_mode,
+ unsigned int vdd)
{
int on;
-#ifdef CONFIG_REGULATOR
- if (host->vcc)
- mmc_regulator_set_ocr(host->vcc, vdd);
-#endif
+ if (host->vcc) {
+ int ret;
+
+ if (power_mode == MMC_POWER_UP) {
+ ret = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
+ if (ret)
+ dev_err(mmc_dev(host->mmc),
+ "could not set regulator OCR\n");
+ } else if (power_mode == MMC_POWER_OFF)
+ ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
+ if (ret)
+ dev_err(mmc_dev(host->mmc),
+ "could not disable regulator\n");
+ }
mmc_power_off() does set ios->vdd to 0 so the original code was fine
wrt to ignoring power_mode.
if (!host->vcc && host->pdata &&
gpio_is_valid(host->pdata->gpio_power)) {
on = ((1 << vdd) & host->pdata->ocr_mask);
@@ -492,7 +504,7 @@ static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
if (host->power_mode != ios->power_mode) {
host->power_mode = ios->power_mode;
- pxamci_set_power(host, ios->vdd);
+ pxamci_set_power(host, ios->power_mode, ios->vdd);
if (ios->power_mode == MMC_POWER_ON)
host->cmdat |= CMDAT_INIT;
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 1575b52..8f5d765 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -212,6 +212,10 @@ struct mmc_host {
struct led_trigger *led; /* activity led */
#endif
+#ifdef CONFIG_REGULATOR
+ bool regulator_enabled; /* regulator state */
+#endif
+
struct dentry *debugfs_root;
unsigned long private[0] ____cacheline_aligned;
@@ -251,7 +255,9 @@ static inline void mmc_signal_sdio_irq(struct mmc_host *host)
struct regulator;
int mmc_regulator_get_ocrmask(struct regulator *supply);
-int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
+int mmc_regulator_set_ocr(struct mmc_host *mmc,
+ struct regulator *supply,
+ unsigned short vdd_bit);
int mmc_card_awake(struct mmc_host *host);
int mmc_card_sleep(struct mmc_host *host);
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/