diff options
| author | Kevin Hilman <khilman@deeprootsystems.com> | 2010-02-24 12:05:45 -0700 |
|---|---|---|
| committer | Paul Walmsley <paul@pwsan.com> | 2010-02-24 12:05:45 -0700 |
| commit | 0007122ad85cc36b1c18c0b59344093ca210d206 (patch) | |
| tree | c5406ff2b8fd1ddd11cc0201c6a10ef47dbd2990 | |
| parent | 80c20d543d142ee54ec85259b77aaf0b83c32db5 (diff) | |
OMAP: omap_device: add omap_device_is_valid()
The omap_device struct contains a 'struct platform_device'. Normally,
converting a platform_device pointer to an omap_device pointer
consists of simply doing a container_of(), as is done currently by the
to_omap_device() macro.
However, if this is attempted when using platform_device that has not
been created as part of the omap_device creation, the container_of()
will point to a memory location before the platform_device pointer
which will contain random data.
Therefore, we need a way to detect valid omap_device pointers. This
patch solves this by using the simple magic number approach.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
| -rw-r--r-- | arch/arm/plat-omap/include/plat/omap_device.h | 2 | ||||
| -rw-r--r-- | arch/arm/plat-omap/omap_device.c | 16 |
2 files changed, 18 insertions, 0 deletions
diff --git a/arch/arm/plat-omap/include/plat/omap_device.h b/arch/arm/plat-omap/include/plat/omap_device.h index 76d49171fed..4677ff7d3ab 100644 --- a/arch/arm/plat-omap/include/plat/omap_device.h +++ b/arch/arm/plat-omap/include/plat/omap_device.h @@ -62,6 +62,7 @@ * */ struct omap_device { + u32 magic; struct platform_device pdev; struct omap_hwmod **hwmods; struct omap_device_pm_latency *pm_lats; @@ -81,6 +82,7 @@ int omap_device_shutdown(struct platform_device *pdev); /* Core code interface */ +bool omap_device_is_valid(struct omap_device *od); int omap_device_count_resources(struct omap_device *od); int omap_device_fill_resources(struct omap_device *od, struct resource *res); diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c index 5195dbb1a39..40289e095fc 100644 --- a/arch/arm/plat-omap/omap_device.c +++ b/arch/arm/plat-omap/omap_device.c @@ -90,6 +90,8 @@ #define IGNORE_WAKEUP_LAT 1 +#define OMAP_DEVICE_MAGIC 0xf00dcafe + /* Private functions */ /** @@ -403,6 +405,8 @@ struct omap_device *omap_device_build_ss(const char *pdev_name, int pdev_id, od->pm_lats = pm_lats; od->pm_lats_cnt = pm_lats_cnt; + od->magic = OMAP_DEVICE_MAGIC; + ret = omap_device_register(od); if (ret) goto odbs_exit4; @@ -589,6 +593,18 @@ int omap_device_align_pm_lat(struct platform_device *pdev, } /** + * omap_device_is_valid - Check if pointer is a valid omap_device + * @od: struct omap_device * + * + * Return whether struct omap_device pointer @od points to a valid + * omap_device. + */ +bool omap_device_is_valid(struct omap_device *od) +{ + return (od && od->magic == OMAP_DEVICE_MAGIC); +} + +/** * omap_device_get_pwrdm - return the powerdomain * associated with @od * @od: struct omap_device * * |