mtd: OneNAND: OMAP2/3: prevent regulator sleeping while OneNAND is in use
authorAdrian Hunter <adrian.hunter@nokia.com>
Fri, 19 Feb 2010 14:39:53 +0000 (15:39 +0100)
committerDavid Woodhouse <David.Woodhouse@intel.com>
Thu, 6 Jan 2011 15:34:34 +0000 (15:34 +0000)
Prevent OneNAND's voltage regulator from going to sleep while
OneNAND is in use, by explicitly enabling and disabling the
regulator as appropriate.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
arch/arm/plat-omap/include/plat/onenand.h
drivers/mtd/onenand/omap2.c

index 72f433d..affe87e 100644 (file)
@@ -23,6 +23,7 @@ struct omap_onenand_platform_data {
        int                     (*onenand_setup)(void __iomem *, int freq);
        int                     dma_channel;
        u8                      flags;
+       u8                      regulator_can_sleep;
 };
 
 #define ONENAND_MAX_PARTITIONS 8
index 324402f..1a07bfc 100644 (file)
@@ -35,6 +35,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/regulator/consumer.h>
 
 #include <asm/mach/flash.h>
 #include <plat/gpmc.h>
@@ -63,6 +64,7 @@ struct omap2_onenand {
        int dma_channel;
        int freq;
        int (*setup)(void __iomem *base, int freq);
+       struct regulator *regulator;
 };
 
 #ifdef CONFIG_MTD_PARTITIONS
@@ -601,6 +603,30 @@ static void omap2_onenand_shutdown(struct platform_device *pdev)
        memset((__force void *)c->onenand.base, 0, ONENAND_BUFRAM_SIZE);
 }
 
+static int omap2_onenand_enable(struct mtd_info *mtd)
+{
+       int ret;
+       struct omap2_onenand *c = container_of(mtd, struct omap2_onenand, mtd);
+
+       ret = regulator_enable(c->regulator);
+       if (ret != 0)
+               dev_err(&c->pdev->dev, "cant enable regulator\n");
+
+       return ret;
+}
+
+static int omap2_onenand_disable(struct mtd_info *mtd)
+{
+       int ret;
+       struct omap2_onenand *c = container_of(mtd, struct omap2_onenand, mtd);
+
+       ret = regulator_disable(c->regulator);
+       if (ret != 0)
+               dev_err(&c->pdev->dev, "cant disable regulator\n");
+
+       return ret;
+}
+
 static int __devinit omap2_onenand_probe(struct platform_device *pdev)
 {
        struct omap_onenand_platform_data *pdata;
@@ -715,8 +741,18 @@ static int __devinit omap2_onenand_probe(struct platform_device *pdev)
                }
        }
 
+       if (pdata->regulator_can_sleep) {
+               c->regulator = regulator_get(&pdev->dev, "vonenand");
+               if (IS_ERR(c->regulator)) {
+                       dev_err(&pdev->dev,  "Failed to get regulator\n");
+                       goto err_release_dma;
+               }
+               c->onenand.enable = omap2_onenand_enable;
+               c->onenand.disable = omap2_onenand_disable;
+       }
+
        if ((r = onenand_scan(&c->mtd, 1)) < 0)
-               goto err_release_dma;
+               goto err_release_regulator;
 
        switch ((c->onenand.version_id >> 4) & 0xf) {
        case 0:
@@ -751,6 +787,8 @@ static int __devinit omap2_onenand_probe(struct platform_device *pdev)
 
 err_release_onenand:
        onenand_release(&c->mtd);
+err_release_regulator:
+       regulator_put(c->regulator);
 err_release_dma:
        if (c->dma_channel != -1)
                omap_free_dma(c->dma_channel);
@@ -777,6 +815,7 @@ static int __devexit omap2_onenand_remove(struct platform_device *pdev)
        struct omap2_onenand *c = dev_get_drvdata(&pdev->dev);
 
        onenand_release(&c->mtd);
+       regulator_put(c->regulator);
        if (c->dma_channel != -1)
                omap_free_dma(c->dma_channel);
        omap2_onenand_shutdown(pdev);