mfd: Add mfd_clone_cell(), convert cs5535-mfd/olpc-xo1 to it

Replace mfd_shared_platform_driver_register with mfd_clone_cell.  The
former was called by an mfd client, and registered both a platform driver
and device.  The latter is called by an mfd driver, and registers only a
platform device.

The downside of this is that mfd drivers need to be modified whenever
new clients are added that share a cell; the upside is that it fits
Linux's driver model better.  It's also simpler.

This also converts cs5535-mfd/olpc-xo1 from the old API.  cs5535-mfd
now creates the olpc-xo1-{acpi,pms} devices, while olpc-xo1 binds to
them via platform drivers.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 18 insertions, 9 deletions

diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
index 1408bf8eed5f..ad1b19aa6508 100644
--- a/include/linux/mfd/core.h
+++ b/include/linux/mfd/core.h
@@ -63,6 +63,24 @@ extern int mfd_cell_enable(struct platform_device *pdev);
 extern int mfd_cell_disable(struct platform_device *pdev);
 
 /*
+ * "Clone" multiple platform devices for a single cell. This is to be used
+ * for devices that have multiple users of a cell.  For example, if an mfd
+ * driver wants the cell "foo" to be used by a GPIO driver, an MTD driver,
+ * and a platform driver, the following bit of code would be use after first
+ * calling mfd_add_devices():
+ *
+ * const char *fclones[] = { "foo-gpio", "foo-mtd" };
+ * err = mfd_clone_cells("foo", fclones, ARRAY_SIZE(fclones));
+ *
+ * Each driver (MTD, GPIO, and platform driver) would then register
+ * platform_drivers for "foo-mtd", "foo-gpio", and "foo", respectively.
+ * The cell's .enable/.disable hooks should be used to deal with hardware
+ * resource contention.
+ */
+extern int mfd_clone_cell(const char *cell, const char **clones,
+                size_t n_clones);
+
+/*
  * Given a platform device that's been created by mfd_add_devices(), fetch
  * the mfd_cell that created it.
  */
@@ -87,13 +105,4 @@ extern int mfd_add_devices(struct device *parent, int id,
 
 extern void mfd_remove_devices(struct device *parent);
 
-/*
- * For MFD drivers with clients sharing access to resources, these create
- * multiple platform devices per cell.  Contention handling must still be
- * handled via drivers (ie, with enable/disable hooks).
- */
-extern int mfd_shared_platform_driver_register(struct platform_driver *drv,
-                const char *cellname);
-extern void mfd_shared_platform_driver_unregister(struct platform_driver *drv);
-
 #endif