[PATCH V2] hwrng: OMAP: Fix assumption that runtime_get_sync will always succeed

[Herbert Xu]

On Fri, Jun 24, 2016 at 11:50:39AM -0500, Nishanth Menon wrote:
> pm_runtime_get_sync does return a error value that must be checked for
> error conditions, else, due to various reasons, the device maynot be
> enabled and the system will crash due to lack of clock to the hardware
> module.
> 
> Before:
> 12.562784] [00000000] *pgd=fe193835
> 12.562792] Internal error: : 1406 [#1] SMP ARM
> [...]
> 12.562864] CPU: 1 PID: 241 Comm: modprobe Not tainted 4.7.0-rc4-next-20160624 #2
> 12.562867] Hardware name: Generic DRA74X (Flattened Device Tree)
> 12.562872] task: ed51f140 ti: ed44c000 task.ti: ed44c000
> 12.562886] PC is at omap4_rng_init+0x20/0x84 [omap_rng]
> 12.562899] LR is at set_current_rng+0xc0/0x154 [rng_core]
> [...]
> 
> After the proper checks:
> [   94.366705] omap_rng 48090000.rng: _od_fail_runtime_resume: FIXME:
> missing hwmod/omap_dev info
> [   94.375767] omap_rng 48090000.rng: Failed to runtime_get device -19
> [   94.382351] omap_rng 48090000.rng: initialization failed.
> 
> Fixes: 665d92fa85b5 ("hwrng: OMAP: convert to use runtime PM")
> Cc: Paul Walmsley <paul at pwsan.com>
> Signed-off-by: Nishanth Menon <nm at ti.com>
> ---
> Changes in V2:
> 	- Added runtime_put_noidle when get_sync fails to ensure proper refcounting

Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt