omap mailbox: add save_/restore_ctx() for PM

To preserve the registers during off-mode
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>

arch/arm/mach-omap2/mailbox.c

@@ -30,6 +30,9 @@
 #define MAILBOX_IRQ_NEWMSG(u)		(1 << (2 * (u)))
 #define MAILBOX_IRQ_NOTFULL(u)		(1 << (2 * (u) + 1))
 
+#define MBOX_REG_SIZE			0x120
+#define MBOX_NR_REGS			(MBOX_REG_SIZE / sizeof(u32))
+
 static void __iomem *mbox_base;
 
 struct omap_mbox2_fifo {
@@ -45,6 +48,7 @@ struct omap_mbox2_priv {
 	unsigned long irqstatus;
 	u32 newmsg_bit;
 	u32 notfull_bit;
+	u32 ctx[MBOX_NR_REGS];
 };
 
 static struct clk *mbox_ick_handle;
@@ -165,6 +169,32 @@ static int omap2_mbox_is_irq(struct omap_mbox *mbox,
 	return (enable & status & bit);
 }
 
+static void omap2_mbox_save_ctx(struct omap_mbox *mbox)
+{
+	int i;
+	struct omap_mbox2_priv *p = mbox->priv;
+
+	for (i = 0; i < MBOX_NR_REGS; i++) {
+		p->ctx[i] = mbox_read_reg(i * sizeof(u32));
+
+		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
+			i, p->ctx[i]);
+	}
+}
+
+static void omap2_mbox_restore_ctx(struct omap_mbox *mbox)
+{
+	int i;
+	struct omap_mbox2_priv *p = mbox->priv;
+
+	for (i = 0; i < MBOX_NR_REGS; i++) {
+		mbox_write_reg(p->ctx[i], i * sizeof(u32));
+
+		dev_dbg(mbox->dev, "%s: [%02x] %08x\n", __func__,
+			i, p->ctx[i]);
+	}
+}
+
 static struct omap_mbox_ops omap2_mbox_ops = {
 	.type		= OMAP_MBOX_TYPE2,
 	.startup	= omap2_mbox_startup,
@@ -177,6 +207,8 @@ static struct omap_mbox_ops omap2_mbox_ops = {
 	.disable_irq	= omap2_mbox_disable_irq,
 	.ack_irq	= omap2_mbox_ack_irq,
 	.is_irq		= omap2_mbox_is_irq,
+	.save_ctx	= omap2_mbox_save_ctx,
+	.restore_ctx	= omap2_mbox_restore_ctx,
 };
 
 /*

arch/arm/plat-omap/include/mach/mailbox.h

@@ -33,6 +33,9 @@ struct omap_mbox_ops {
 	void		(*disable_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
 	void		(*ack_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
 	int		(*is_irq)(struct omap_mbox *mbox, omap_mbox_irq_t irq);
+	/* ctx */
+	void		(*save_ctx)(struct omap_mbox *mbox);
+	void		(*restore_ctx)(struct omap_mbox *mbox);
 };
 
 struct omap_mbox_queue {
@@ -70,4 +73,24 @@ void omap_mbox_put(struct omap_mbox *);
 int omap_mbox_register(struct device *parent, struct omap_mbox *);
 int omap_mbox_unregister(struct omap_mbox *);
 
+static inline void omap_mbox_save_ctx(struct omap_mbox *mbox)
+{
+	if (!mbox->ops->save_ctx) {
+		dev_err(mbox->dev, "%s:\tno save\n", __func__);
+		return;
+	}
+
+	mbox->ops->save_ctx(mbox);
+}
+
+static inline void omap_mbox_restore_ctx(struct omap_mbox *mbox)
+{
+	if (!mbox->ops->restore_ctx) {
+		dev_err(mbox->dev, "%s:\tno restore\n", __func__);
+		return;
+	}
+
+	mbox->ops->restore_ctx(mbox);
+}
+
 #endif /* MAILBOX_H */