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path: root/drivers/mfd/mfd-core.c
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Diffstat (limited to 'drivers/mfd/mfd-core.c')
-rw-r--r--drivers/mfd/mfd-core.c118
1 files changed, 106 insertions, 12 deletions
diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
index d83ad0f141af..f4c8c844b913 100644
--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -18,6 +18,56 @@
#include <linux/pm_runtime.h>
#include <linux/slab.h>
+int mfd_cell_enable(struct platform_device *pdev)
+{
+ const struct mfd_cell *cell = mfd_get_cell(pdev);
+ int err = 0;
+
+ /* only call enable hook if the cell wasn't previously enabled */
+ if (atomic_inc_return(cell->usage_count) == 1)
+ err = cell->enable(pdev);
+
+ /* if the enable hook failed, decrement counter to allow retries */
+ if (err)
+ atomic_dec(cell->usage_count);
+
+ return err;
+}
+EXPORT_SYMBOL(mfd_cell_enable);
+
+int mfd_cell_disable(struct platform_device *pdev)
+{
+ const struct mfd_cell *cell = mfd_get_cell(pdev);
+ int err = 0;
+
+ /* only disable if no other clients are using it */
+ if (atomic_dec_return(cell->usage_count) == 0)
+ err = cell->disable(pdev);
+
+ /* if the disable hook failed, increment to allow retries */
+ if (err)
+ atomic_inc(cell->usage_count);
+
+ /* sanity check; did someone call disable too many times? */
+ WARN_ON(atomic_read(cell->usage_count) < 0);
+
+ return err;
+}
+EXPORT_SYMBOL(mfd_cell_disable);
+
+static int mfd_platform_add_cell(struct platform_device *pdev,
+ const struct mfd_cell *cell)
+{
+ if (!cell)
+ return 0;
+
+ pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL);
+ if (!pdev->mfd_cell)
+ return -ENOMEM;
+
+ return 0;
+}
+
static int mfd_add_device(struct device *parent, int id,
const struct mfd_cell *cell,
struct resource *mem_base,
@@ -37,14 +87,10 @@ static int mfd_add_device(struct device *parent, int id,
goto fail_device;
pdev->dev.parent = parent;
- platform_set_drvdata(pdev, cell->driver_data);
- if (cell->data_size) {
- ret = platform_device_add_data(pdev,
- cell->platform_data, cell->data_size);
- if (ret)
- goto fail_res;
- }
+ ret = mfd_platform_add_cell(pdev, cell);
+ if (ret)
+ goto fail_res;
for (r = 0; r < cell->num_resources; r++) {
res[r].name = cell->resources[r].name;
@@ -90,7 +136,6 @@ static int mfd_add_device(struct device *parent, int id,
return 0;
-/* platform_device_del(pdev); */
fail_res:
kfree(res);
fail_device:
@@ -100,14 +145,22 @@ fail_alloc:
}
int mfd_add_devices(struct device *parent, int id,
- const struct mfd_cell *cells, int n_devs,
+ struct mfd_cell *cells, int n_devs,
struct resource *mem_base,
int irq_base)
{
int i;
int ret = 0;
+ atomic_t *cnts;
+
+ /* initialize reference counting for all cells */
+ cnts = kcalloc(sizeof(*cnts), n_devs, GFP_KERNEL);
+ if (!cnts)
+ return -ENOMEM;
for (i = 0; i < n_devs; i++) {
+ atomic_set(&cnts[i], 0);
+ cells[i].usage_count = &cnts[i];
ret = mfd_add_device(parent, id, cells + i, mem_base, irq_base);
if (ret)
break;
@@ -120,17 +173,58 @@ int mfd_add_devices(struct device *parent, int id,
}
EXPORT_SYMBOL(mfd_add_devices);
-static int mfd_remove_devices_fn(struct device *dev, void *unused)
+static int mfd_remove_devices_fn(struct device *dev, void *c)
{
- platform_device_unregister(to_platform_device(dev));
+ struct platform_device *pdev = to_platform_device(dev);
+ const struct mfd_cell *cell = mfd_get_cell(pdev);
+ atomic_t **usage_count = c;
+
+ /* find the base address of usage_count pointers (for freeing) */
+ if (!*usage_count || (cell->usage_count < *usage_count))
+ *usage_count = cell->usage_count;
+
+ platform_device_unregister(pdev);
return 0;
}
void mfd_remove_devices(struct device *parent)
{
- device_for_each_child(parent, NULL, mfd_remove_devices_fn);
+ atomic_t *cnts = NULL;
+
+ device_for_each_child(parent, &cnts, mfd_remove_devices_fn);
+ kfree(cnts);
}
EXPORT_SYMBOL(mfd_remove_devices);
+int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones)
+{
+ struct mfd_cell cell_entry;
+ struct device *dev;
+ struct platform_device *pdev;
+ int i;
+
+ /* fetch the parent cell's device (should already be registered!) */
+ dev = bus_find_device_by_name(&platform_bus_type, NULL, cell);
+ if (!dev) {
+ printk(KERN_ERR "failed to find device for cell %s\n", cell);
+ return -ENODEV;
+ }
+ pdev = to_platform_device(dev);
+ memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry));
+
+ WARN_ON(!cell_entry.enable);
+
+ for (i = 0; i < n_clones; i++) {
+ cell_entry.name = clones[i];
+ /* don't give up if a single call fails; just report error */
+ if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, NULL, 0))
+ dev_err(dev, "failed to create platform device '%s'\n",
+ clones[i]);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(mfd_clone_cell);
+
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov");