fbdev: sh_mobile_meram: Backup/restore device registers on shutdown/resume

Save and reconfigure the MERAM registers when the MERAM is powered down
and restored

Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>

diff --git a/drivers/video/sh_mobile_meram.c b/drivers/video/sh_mobile_meram.c
index cfa1a78..39f28a1 100644 (file)
--- a/drivers/video/sh_mobile_meram.c
+++ b/drivers/video/sh_mobile_meram.c
@@ -37,12 +37,31 @@
 #define MEQSEL1 0x40
 #define MEQSEL2 0x44
 
+static unsigned long common_regs[] = {
+       MEVCR1,
+       MEQSEL1,
+       MEQSEL2,
+};
+#define CMN_REGS_SIZE ARRAY_SIZE(common_regs)
+
+static unsigned long icb_regs[] = {
+       MExxCTL,
+       MExxBSIZE,
+       MExxMNCF,
+       MExxSARA,
+       MExxSARB,
+       MExxSBSIZE,
+};
+#define ICB_REGS_SIZE ARRAY_SIZE(icb_regs)
+
 struct sh_mobile_meram_priv {
        void __iomem    *base;
        struct mutex    lock;
        unsigned long   used_icb;
        int             used_meram_cache_regions;
        unsigned long   used_meram_cache[SH_MOBILE_MERAM_ICB_NUM];
+       unsigned long   cmn_saved_regs[CMN_REGS_SIZE];
+       unsigned long   icb_saved_regs[ICB_REGS_SIZE * SH_MOBILE_MERAM_ICB_NUM];
 };
 
 /* settings */
@@ -469,6 +488,57 @@ static int sh_mobile_meram_update(struct sh_mobile_meram_info *pdata,
        return 0;
 }
 
+static int sh_mobile_meram_runtime_suspend(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct sh_mobile_meram_priv *priv = platform_get_drvdata(pdev);
+       int k, j;
+
+       for (k = 0; k < CMN_REGS_SIZE; k++)
+               priv->cmn_saved_regs[k] = meram_read_reg(priv->base,
+                       common_regs[k]);
+
+       for (j = 0; j < 32; j++) {
+               if (!test_bit(j, &priv->used_icb))
+                       continue;
+               for (k = 0; k < ICB_REGS_SIZE; k++) {
+                       priv->icb_saved_regs[j * ICB_REGS_SIZE + k] =
+                               meram_read_icb(priv->base, j, icb_regs[k]);
+                       /* Reset ICB on resume */
+                       if (icb_regs[k] == MExxCTL)
+                               priv->icb_saved_regs[j * ICB_REGS_SIZE + k] =
+                                       0x70;
+               }
+       }
+       return 0;
+}
+
+static int sh_mobile_meram_runtime_resume(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct sh_mobile_meram_priv *priv = platform_get_drvdata(pdev);
+       int k, j;
+
+       for (j = 0; j < 32; j++) {
+               if (!test_bit(j, &priv->used_icb))
+                       continue;
+               for (k = 0; k < ICB_REGS_SIZE; k++) {
+                       meram_write_icb(priv->base, j, icb_regs[k],
+                       priv->icb_saved_regs[j * ICB_REGS_SIZE + k]);
+               }
+       }
+
+       for (k = 0; k < CMN_REGS_SIZE; k++)
+               meram_write_reg(priv->base, common_regs[k],
+                       priv->cmn_saved_regs[k]);
+       return 0;
+}
+
+static const struct dev_pm_ops sh_mobile_meram_dev_pm_ops = {
+       .runtime_suspend = sh_mobile_meram_runtime_suspend,
+       .runtime_resume = sh_mobile_meram_runtime_resume,
+};
+
 static struct sh_mobile_meram_ops sh_mobile_meram_ops = {
        .module                 = THIS_MODULE,
        .meram_register         = sh_mobile_meram_register,
@@ -557,6 +627,7 @@ static struct platform_driver sh_mobile_meram_driver = {
        .driver = {
                .name           = "sh_mobile_meram",
                .owner          = THIS_MODULE,
+               .pm             = &sh_mobile_meram_dev_pm_ops,
        },
        .probe          = sh_mobile_meram_probe,
        .remove         = sh_mobile_meram_remove,