* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
arch/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
sched/ audio/ crypto/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
Documentation/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
fs/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
graphics/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
net/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
drivers/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
include/, syscall/, wireless/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
configs/: Remove all references to CONFIG_DISABLE_POLL. Standard POSIX poll can no longer be disabled.
Fixes for MFRC522
drivers/contactless/mfrc522.c: in mfrc522_read uid.sak must be different from 0x04 not as before from 0x00. SAK == 0x00 is a valid PICC type
drivers/contactless/mfrc522.c: add interface to read MIFARE Ultralight data
configs/nucleo-l073rz: add mfrc522 support
Approved-by: Gregory Nutt <gnutt@nuttx.org>
Fixed coding standard error in several files. Use of while( is incorrect; a space is required between while and (. Also ran tools/nxstyle and fix thoses complaints as well in most files.
Changes to comply with coding standard. Mostly focused on files with missing space after keyword in if(, switch(, and for(. Offending files also got changes to comply with tools nxstyle. If there were logs of nxstyle complaints, the file also got a taste of tools/indent.sh. Still need to fix occurrences of while( with missing space. There are a lot of them.
Squashed commit of the following:
Change all calls to usleep() in the OS proper to calls to nxsig_usleep()
sched/signal: Add a new OS internal function nxsig_usleep() that is functionally equivalent to usleep() but does not cause a cancellaption point and does not modify the errno variable.
sched/signal: Add a new OS internal function nxsig_sleep() that is functionally equivalent to sleep() but does not cause a cancellaption point.
