staging: bcm2835-audio: clean-up coding style issues

[1] Replace kmalloc and memset with kzalloc in vc_vchi_audio_init(..)
[2] Replace null return value with PTR_ERR(..) values

    in vc_vchi_audio_init(..)

[3] Propagate the PTR_ERR values forward instead of a hardcoded value for easier debugging in bcm2835_audio_open_connection(..)
[4] Replace if (success) else { } after kmalloc with if(error) to fail fast in the work function
[5] De-allocate 'work' when queue_work(..) fails in the work functions
[6] De-allocate 'vchi_instance' when VCHI connection fails or VCHI audio instance initialisation fails in bcm2835_audio_open_connection()

Changes in v7:
-- Added back the debug log messages in bcm2835_audio_open_connection() -- Remove label err_free_memory, re-use label err_free_mem to kfree
vchi_instance in bcm2835_audio_open_connection()
-- Drop patch 7 which removed BUG_ON(instance). Looks like if(instance)
block is WIP, BUG_ON(instance) may be required for debugging in the interim period.

Changes in v6:
-- Add a local variable ret to set error value instead of
returning -EPERM when initialisation of vchi_audio_service fails in bcm2835_audio_open_connection()

Changes in v5:
-- Remove patch which added function names to log messages

Changes in v4:
-- Break-up patch 4 into four smaller patches
-- Add a patch proposing removal of BUG_ON()
-- Make the cover letter verbose

Changes in v3:
-- Fix memory leak when queue_work fails
-- Add __func__ to debug logs

Changes in v2:
-- Return error value -EBUSY instead of -1 when queue_work()
fails

Aishwarya Pant (6):
staging: bcm2835-audio: Replace kmalloc with kzalloc
staging: bcm2835-audio: replace null with error pointer value
staging: bcm2835-audio: propagate PTR_ERR value instead of -EPERM
staging: bcm2835-audio: use conditional only for error case
staging: bcm2835-audio: deallocate work when queue_work(...) fails
staging: bcm2835-audio: fix memory leak in

    bcm2835_audio_open_connection()

 .../vc04_services/bcm2835-audio/bcm2835-vchiq.c    | 87 +++++++++++-----------
 1 file changed, 44 insertions(+), 43 deletions(-)

2.7.4