media: omap3isp: zero-initialize the isp cam_xclk{a,b} initial data
authorJavier Martinez Canillas <javierm@redhat.com>
Sat, 9 Jun 2018 12:22:45 +0000 (08:22 -0400)
committerMauro Carvalho Chehab <mchehab+samsung@kernel.org>
Thu, 28 Jun 2018 13:21:58 +0000 (09:21 -0400)
commit2ec7debd44b49927a6e2861521994cc075a389ed
tree6c2db82d0ae3367a21bc26eb93ce24a0202ebac4
parent5b0a205466578432ce8faadd08f8d7ef895a180f
media: omap3isp: zero-initialize the isp cam_xclk{a,b} initial data

The struct clk_init_data init variable is declared in the isp_xclk_init()
function so is an automatic variable allocated in the stack. But it's not
explicitly zero-initialized, so some init fields are left uninitialized.

This causes the data structure to have undefined values that may confuse
the common clock framework when the clock is registered.

For example, the uninitialized .flags field could have the CLK_IS_CRITICAL
bit set, causing the framework to wrongly prepare the clk on registration.
This leads to the isp_xclk_prepare() callback being called, which in turn
calls to the omap3isp_get() function that increments the isp dev refcount.

Since this omap3isp_get() call is unexpected, this leads to an unbalanced
omap3isp_get() call that prevents the requested IRQ to be later enabled,
due the refcount not being 0 when the correct omap3isp_get() call happens.

Fixes: 9b28ee3c9122 ("[media] omap3isp: Use the common clock framework")

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
drivers/media/platform/omap3isp/isp.c