Squashed commit of the following:
sched: Rename all use of system_t to clock_t.
syscall: Rename all use of system_t to clock_t.
net: Rename all use of system_t to clock_t.
libs: Rename all use of system_t to clock_t.
fs: Rename all use of system_t to clock_t.
drivers: Rename all use of system_t to clock_t.
arch: Rename all use of system_t to clock_t.
include: Remove definition of systime_t; rename all use of system_t to clock_t.
drivers/lcd/ft80x: ACTIVE host command appears to be formatted differently than other host commands; Fix ROM CHIPID. Appears to be big-ending, BCD.
drivers/lcd/ft80x: Fix some compile issues when debug features are enabled.
drivers/lcd and include/nuttx/lcd: Add FT80x support for writing to graphics memory. Also add some definitions needed by apps/examples/ft80x for bitmap manipulation.
drivers/lcd: Review/update FT80x initializatin logic
drivers/lcd: Rename ft80x_base.c to just ft80x.c. Add logic to notify FT80X clients of events via signals.
drivers/lcd: Trivial updates to naming. Add some new definitions.
Squashed commit of the following:
drivers/lcd: Finishes off basic FT80X. Still missing some niceties.
drivers/lcd: Rethink FT80X display list interface.
drivers/lcd: More FT800x display list logic. Still not complete.
drivers/lcd: Add some basic FT80x initialization logic.
drivers/lcd: Add ft80x display list IOCTL framework. Still missing low level display list operations.
drivers/lcd: FT80x driver cannot be a standard LCD driver but must, instead, be a custom character driver.
drivers/lcd: Add FT800 co-processor commands and display list helpers.
drivers/lcd: Add SPI interface and framework for the initialization and the basic LCD driver.
drivers/lcd: Add beginnings of some FT80x implementation.
drivers/lcd: Add definitions for the FTDI FT801 part
include/nuttx/lcd/ft800.h: Add initial FT800 interface definition.
drivers/lcd: Add ft800 header file.
configs/flipnclick-pic32mz: Add an nxlines configuration for use in testing the custom HiletGo Click board.
arch/mips/src/pic32mz: Correct some SPI-related typos. configs/flipnclick-pic32mz: Finishes integration of HiletGo OLED. drivers/lcd: Finish support for HiletGo OLED.
drivers/lcd: Add configuration support for HiletGo OLED. configs/flipnclick-pic32mz: Add board support for HiletGo OLED.
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.
This commit backs out most of commit b4747286b1. That change was added because sem_wait() would sometimes cause cancellation points inappropriated. But with these recent changes, nxsem_wait() is used instead and it is not a cancellation point.
In the OS, all calls to sem_wait() changed to nxsem_wait(). nxsem_wait() does not return errors via errno so each place where nxsem_wait() is now called must not examine the errno variable.
In all OS functions (not libraries), change sem_wait() to nxsem_wait(). This will prevent the OS from creating bogus cancellation points and from modifying the per-task errno variable.
sched/semaphore: Add the function nxsem_wait(). This is a new internal OS interface. It is functionally equivalent to sem_wait() except that (1) it is not a cancellation point, and (2) it does not set the per-thread errno value on return.
sched/semaphore: Add nxsem_post() which is identical to sem_post() except that it never modifies the errno variable. Changed all references to sem_post in the OS to nxsem_post().
sched/semaphore: Add nxsem_destroy() which is identical to sem_destroy() except that it never modifies the errno variable. Changed all references to sem_destroy() in the OS to nxsem_destroy().
libc/semaphore and sched/semaphore: Add nxsem_getprotocol() and nxsem_setprotocola which are identical to sem_getprotocol() and set_setprotocol() except that they never modifies the errno variable. Changed all references to sem_setprotocol in the OS to nxsem_setprotocol(). sem_getprotocol() was not used in the OS
libc/semaphore: Add nxsem_getvalue() which is identical to sem_getvalue() except that it never modifies the errno variable. Changed all references to sem_getvalue in the OS to nxsem_getvalue().
sched/semaphore: Rename all internal private functions from sem_xyz to nxsem_xyz. The sem_ prefix is (will be) reserved only for the application semaphore interfaces.
libc/semaphore: Add nxsem_init() which is identical to sem_init() except that it never modifies the errno variable. Changed all references to sem_init in the OS to nxsem_init().
sched/semaphore: Rename sem_tickwait() to nxsem_tickwait() so that it is clear this is an internal OS function.
sched/semaphoate: Rename sem_reset() to nxsem_reset() so that it is clear this is an internal OS function.