[ 052/221] mfd: Only unregister platform devices allocated by the mfd core

Greg Kroah-Hartman
2013-01-15T22:28:33Z

From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>

commit b9fbb62eb61452d728c39b2e5020739c575aac53 upstream.

mfd_remove_devices would iterate over all devices sharing a parent with
an mfd device regardless of whether they were allocated by the mfd core
or not. This especially caused problems when the device structure was
not contained within a platform_device, because to_platform_device is
used on each device pointer.

This patch defines a device_type for mfd devices and checks this is
present from mfd_remove_devices_fn before processing the device.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Tested-by: Peter Tyser <ptyser@xes-inc.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/mfd/mfd-core.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)

--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -21,6 +21,10 @@
#include <linux/irqdomain.h>
#include <linux/of.h>

+static struct device_type mfd_dev_type = {
+ .name = "mfd_device",
+};
+
int mfd_cell_enable(struct platform_device *pdev)
{
const struct mfd_cell *cell = mfd_get_cell(pdev);
@@ -91,6 +95,7 @@ static int mfd_add_device(struct device
goto fail_device;

pdev->dev.parent = parent;
+ pdev->dev.type = &mfd_dev_type;

if (parent->of_node && cell->of_compatible) {
for_each_child_of_node(parent->of_node, np) {
@@ -204,10 +209,16 @@ EXPORT_SYMBOL(mfd_add_devices);

static int mfd_remove_devices_fn(struct device *dev, void *c)
{
- struct platform_device *pdev = to_platform_device(dev);
- const struct mfd_cell *cell = mfd_get_cell(pdev);
+ struct platform_device *pdev;
+ const struct mfd_cell *cell;
atomic_t **usage_count = c;

+ if (dev->type != &mfd_dev_type)
+ return 0;
+
+ pdev = to_platform_device(dev);
+ cell = mfd_get_cell(pdev);
+
/* find the base address of usage_count pointers (for freeing) */
if (!*usage_count || (cell->usage_count < *usage_count))
*usage_count = cell->usage_count;