mfd: Add sharing for cs5535 acpi/pms cells

This enables sharing of cs5535-mfd cells via the new mfd_shared_* API.
Hooks for enable/disble of resources are added, with refcounting of
resources being automatically handled so that cs5535_mfd_res_enable/disable
are only called when necessary.

Clients of cs5535-mfd (in this case, olpc-xo1.c) are also modified to
use the mfd_shared API.  The platform drivers are also renamed to
olpc-xo1-{pms,acpi}, and resource enabling/disabling is replaced
with mfd_shared API calls.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/cs5535-mfd.c b/drivers/mfd/cs5535-mfd.c
index 59ca6f1..886a068 100644
--- a/drivers/mfd/cs5535-mfd.c
+++ b/drivers/mfd/cs5535-mfd.c
@@ -39,6 +39,37 @@
 	NR_BARS,
 };
 
+static int cs5535_mfd_res_enable(struct platform_device *pdev)
+{
+	struct resource *res;
+
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "can't fetch device resource info\n");
+		return -EIO;
+	}
+
+	if (!request_region(res->start, resource_size(res), DRV_NAME)) {
+		dev_err(&pdev->dev, "can't request region\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static int cs5535_mfd_res_disable(struct platform_device *pdev)
+{
+	struct resource *res;
+	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "can't fetch device resource info\n");
+		return -EIO;
+	}
+
+	release_region(res->start, resource_size(res));
+	return 0;
+}
+
 static __devinitdata struct resource cs5535_mfd_resources[NR_BARS];
 
 static __devinitdata struct mfd_cell cs5535_mfd_cells[] = {
@@ -65,12 +96,18 @@
 		.name = "cs5535-pms",
 		.num_resources = 1,
 		.resources = &cs5535_mfd_resources[PMS_BAR],
+
+		.enable = cs5535_mfd_res_enable,
+		.disable = cs5535_mfd_res_disable,
 	},
 	{
 		.id = ACPI_BAR,
 		.name = "cs5535-acpi",
 		.num_resources = 1,
 		.resources = &cs5535_mfd_resources[ACPI_BAR],
+
+		.enable = cs5535_mfd_res_enable,
+		.disable = cs5535_mfd_res_disable,
 	},
 };