1 files changed, 52 insertions, 26 deletions

diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c
index 349a8d1caca1..98d06b3ee913 100644
--- a/drivers/rtc/rtc-ds1685.c
+++ b/drivers/rtc/rtc-ds1685.c
@@ -31,7 +31,10 @@
 
 
 /* ----------------------------------------------------------------------- */
-/* Standard read/write functions if platform does not provide overrides */
+/*
+ *  Standard read/write
+ *  all registers are mapped in CPU address space
+ */
 
 /**
  * ds1685_read - read a value from an rtc register.
@@ -59,6 +62,35 @@ ds1685_write(struct ds1685_priv *rtc, int reg, u8 value)
 }
 /* ----------------------------------------------------------------------- */
 
+/*
+ * Indirect read/write functions
+ * access happens via address and data register mapped in CPU address space
+ */
+
+/**
+ * ds1685_indirect_read - read a value from an rtc register.
+ * @rtc: pointer to the ds1685 rtc structure.
+ * @reg: the register address to read.
+ */
+static u8
+ds1685_indirect_read(struct ds1685_priv *rtc, int reg)
+{
+	writeb(reg, rtc->regs);
+	return readb(rtc->data);
+}
+
+/**
+ * ds1685_indirect_write - write a value to an rtc register.
+ * @rtc: pointer to the ds1685 rtc structure.
+ * @reg: the register address to write.
+ * @value: value to write to the register.
+ */
+static void
+ds1685_indirect_write(struct ds1685_priv *rtc, int reg, u8 value)
+{
+	writeb(reg, rtc->regs);
+	writeb(value, rtc->data);
+}
 
 /* ----------------------------------------------------------------------- */
 /* Inlined functions */
@@ -1062,42 +1094,36 @@ ds1685_rtc_probe(struct platform_device *pdev)
 	if (!rtc)
 		return -ENOMEM;
 
-	/*
-	 * Allocate/setup any IORESOURCE_MEM resources, if required.  Not all
-	 * platforms put the RTC in an easy-access place.  Like the SGI Octane,
-	 * which attaches the RTC to a "ByteBus", hooked to a SuperIO chip
-	 * that sits behind the IOC3 PCI metadevice.
-	 */
-	if (pdata->alloc_io_resources) {
+	/* Setup resources and access functions */
+	switch (pdata->access_type) {
+	case ds1685_reg_direct:
+		rtc->regs = devm_platform_ioremap_resource(pdev, 0);
+		if (IS_ERR(rtc->regs))
+			return PTR_ERR(rtc->regs);
+		rtc->read = ds1685_read;
+		rtc->write = ds1685_write;
+		break;
+	case ds1685_reg_indirect:
 		rtc->regs = devm_platform_ioremap_resource(pdev, 0);
 		if (IS_ERR(rtc->regs))
 			return PTR_ERR(rtc->regs);
+		rtc->data = devm_platform_ioremap_resource(pdev, 1);
+		if (IS_ERR(rtc->data))
+			return PTR_ERR(rtc->data);
+		rtc->read = ds1685_indirect_read;
+		rtc->write = ds1685_indirect_write;
+		break;
 	}
 
+	if (!rtc->read || !rtc->write)
+		return -ENXIO;
+
 	/* Get the register step size. */
 	if (pdata->regstep > 0)
 		rtc->regstep = pdata->regstep;
 	else
 		rtc->regstep = 1;
 
-	/* Platform read function, else default if mmio setup */
-	if (pdata->plat_read)
-		rtc->read = pdata->plat_read;
-	else
-		if (pdata->alloc_io_resources)
-			rtc->read = ds1685_read;
-		else
-			return -ENXIO;
-
-	/* Platform write function, else default if mmio setup */
-	if (pdata->plat_write)
-		rtc->write = pdata->plat_write;
-	else
-		if (pdata->alloc_io_resources)
-			rtc->write = ds1685_write;
-		else
-			return -ENXIO;
-
 	/* Platform pre-shutdown function, if defined. */
 	if (pdata->plat_prepare_poweroff)
 		rtc->prepare_poweroff = pdata->plat_prepare_poweroff;