mmc: Move regulator handling closer to core

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.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Adrian Hunter <adrian.hunter@nokia.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Sundar Iyer <sundar.iyer@stericsson.com>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Matt Fleming <matt@console-pimps.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Eric Miao <eric.y.miao@gmail.com>
Cc: Cliff Brake <cbrake@bec-systems.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index c5e3c9b..46029d5 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -772,8 +772,9 @@ 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.
  *
@@ -781,15 +782,12 @@ 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;
@@ -820,17 +818,25 @@ 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;
        }
 
+       if (result)
+               dev_err(mmc_dev(mmc),
+                       "could not set regulator OCR (%d)\n", result);
        return result;
 }
 EXPORT_SYMBOL(mmc_regulator_set_ocr);
 
-#endif
+#endif /* CONFIG_REGULATOR */
 
 /*
  * Mask off any voltages we don't support and select

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 5f2e72d..87b4fc6 100644 (file)
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -523,19 +523,27 @@ 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);
                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), "unable to set OCR\n");
+                               /*
+                                * The .set_ios() function in the mmc_host_ops
+                                * struct return void, and failing to set the
+                                * power should be rare so we print an error
+                                * and return here.
+                                */
+                               return;
+                       }
+               }
                if (host->plat->vdd_handler)
                        pwr |= host->plat->vdd_handler(mmc_dev(mmc), ios->vdd,
                                                       ios->power_mode);
@@ -869,8 +877,8 @@ static int __devexit mmci_remove(struct amba_device *dev)
                clk_disable(host->clk);
                clk_put(host->clk);
 
-               if (regulator_is_enabled(host->vcc))
-                       regulator_disable(host->vcc);
+               if (host->vcc)
+                       mmc_regulator_set_ocr(mmc, host->vcc, 0);
                regulator_put(host->vcc);
 
                mmc_free_host(mmc);

diff --git a/drivers/mmc/host/omap_hsmmc.c b/drivers/mmc/host/omap_hsmmc.c
index 03c26e0..8c863cc 100644 (file)
--- a/drivers/mmc/host/omap_hsmmc.c
+++ b/drivers/mmc/host/omap_hsmmc.c
@@ -250,9 +250,9 @@ static int omap_hsmmc_1_set_power(struct device *dev, int slot, int power_on,
                mmc_slot(host).before_set_reg(dev, slot, power_on, vdd);
 
        if (power_on)
-               ret = mmc_regulator_set_ocr(host->vcc, vdd);
+               ret = mmc_regulator_set_ocr(host->mmc, host->vcc, vdd);
        else
-               ret = mmc_regulator_set_ocr(host->vcc, 0);
+               ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
 
        if (mmc_slot(host).after_set_reg)
                mmc_slot(host).after_set_reg(dev, slot, power_on, vdd);
@@ -291,18 +291,23 @@ 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);
                /* 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 +348,9 @@ 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 b7dfcac..7257738 100644 (file)
--- a/drivers/mmc/host/pxamci.c
+++ b/drivers/mmc/host/pxamci.c
@@ -99,14 +99,25 @@ 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 int 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)
+                               return ret;
+               } else if (power_mode == MMC_POWER_OFF) {
+                       ret = mmc_regulator_set_ocr(host->mmc, host->vcc, 0);
+                       if (ret)
+                               return ret;
+               }
+       }
        if (!host->vcc && host->pdata &&
            gpio_is_valid(host->pdata->gpio_power)) {
                on = ((1 << vdd) & host->pdata->ocr_mask);
@@ -115,6 +126,8 @@ static inline void pxamci_set_power(struct pxamci_host *host, unsigned int vdd)
        }
        if (!host->vcc && host->pdata && host->pdata->setpower)
                host->pdata->setpower(mmc_dev(host->mmc), vdd);
+
+       return 0;
 }
 
 static void pxamci_stop_clock(struct pxamci_host *host)
@@ -490,9 +503,21 @@ static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
        }
 
        if (host->power_mode != ios->power_mode) {
+               int ret;
+
                host->power_mode = ios->power_mode;
 
-               pxamci_set_power(host, ios->vdd);
+               ret = pxamci_set_power(host, ios->power_mode, ios->vdd);
+               if (ret) {
+                       dev_err(mmc_dev(mmc), "unable to set power\n");
+                       /*
+                        * The .set_ios() function in the mmc_host_ops
+                        * struct return void, and failing to set the
+                        * power should be rare so we print an error and
+                        * return here.
+                        */
+                       return;
+               }
 
                if (ios->power_mode == MMC_POWER_ON)
                        host->cmdat |= CMDAT_INIT;
@@ -503,8 +528,8 @@ static void pxamci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
        else
                host->cmdat &= ~CMDAT_SD_4DAT;
 
-       pr_debug("PXAMCI: clkrt = %x cmdat = %x\n",
-                host->clkrt, host->cmdat);
+       dev_dbg(mmc_dev(mmc), "PXAMCI: clkrt = %x cmdat = %x\n",
+               host->clkrt, host->cmdat);
 }
 
 static void pxamci_enable_sdio_irq(struct mmc_host *host, int enable)

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 20be040..ccac56a 100644 (file)
--- 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;
@@ -250,8 +254,24 @@ static inline void mmc_signal_sdio_irq(struct mmc_host *host)
 
 struct regulator;
 
+#ifdef CONFIG_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);
+#else
+static inline int mmc_regulator_get_ocrmask(struct regulator *supply)
+{
+       return 0;
+}
+
+static inline int mmc_regulator_set_ocr(struct mmc_host *mmc,
+                                struct regulator *supply,
+                                unsigned short vdd_bit)
+{
+       return 0;
+}
+#endif
 
 int mmc_card_awake(struct mmc_host *host);
 int mmc_card_sleep(struct mmc_host *host);