diff options
| author | Andres Salomon <dilinger@queued.net> | 2011-02-17 19:07:34 -0800 |
|---|---|---|
| committer | Samuel Ortiz <sameo@linux.intel.com> | 2011-03-23 10:41:58 +0100 |
| commit | 1e29af62f2b285bd18685da93c3ce8c33ca2d1db (patch) | |
| tree | 662545398e04cfb5b10fa4b13810d47ddd003c98 /include/linux/mfd/core.h | |
| parent | dcb50e83bb86d66d3554ba9c365488669c84d037 (diff) | |
mfd: Add refcounting support to mfd_cells
This provides convenience functions for sharing of cells across
multiple mfd clients. Mfd drivers can provide enable/disable hooks
to actually tweak the hardware, and clients can call
mfd_shared_cell_{en,dis}able without having to worry about whether
or not another client happens to have enabled or disabled the
cell/hardware.
Note that this is purely optional; drivers can continue to use
the mfd_cell's enable/disable hooks for their own purposes, if
desired.
Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'include/linux/mfd/core.h')
| -rw-r--r-- | include/linux/mfd/core.h | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h index 71cd1f983cc..22a2f5ebd9d 100644 --- a/include/linux/mfd/core.h +++ b/include/linux/mfd/core.h @@ -25,8 +25,11 @@ struct mfd_cell { const char *name; int id; + /* refcounting for multiple drivers to use a single cell */ + atomic_t *usage_count; int (*enable)(struct platform_device *dev); int (*disable)(struct platform_device *dev); + int (*suspend)(struct platform_device *dev); int (*resume)(struct platform_device *dev); @@ -51,6 +54,15 @@ struct mfd_cell { }; /* + * Convenience functions for clients using shared cells. Refcounting + * happens automatically, with the cell's enable/disable callbacks + * being called only when a device is first being enabled or no other + * clients are making use of it. + */ +extern int mfd_shared_cell_enable(struct platform_device *pdev); +extern int mfd_shared_cell_disable(struct platform_device *pdev); + +/* * Given a platform device that's been created by mfd_add_devices(), fetch * the mfd_cell that created it. */ @@ -69,7 +81,7 @@ static inline void *mfd_get_data(struct platform_device *pdev) } extern 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); |