• Ohad Ben-Cohen's avatar
    hwspinlock/core: register a bank of hwspinlocks in a single API call · 300bab97
    Ohad Ben-Cohen authored
    Hardware Spinlock devices usually contain numerous locks (known
    devices today support between 32 to 256 locks).
    
    Originally hwspinlock core required drivers to register (and later,
    when needed, unregister) each lock separately.
    
    That worked, but required hwspinlocks drivers to do a bit extra work
    when they were probed/removed.
    
    This patch changes hwspin_lock_{un}register() to allow a bank of
    hwspinlocks to be {un}registered in a single invocation.
    
    A new 'struct hwspinlock_device', which contains an array of 'struct
    hwspinlock's is now being passed to the core upon registration (so
    instead of wrapping each struct hwspinlock, a priv member has been added
    to allow drivers to piggyback their private data with each hwspinlock).
    
    While at it, several per-lock members were moved to be per-device:
    1. struct device *dev
    2. struct hwspinlock_ops *ops
    
    In addition, now that the array of locks is handled by the core,
    there's no reason to maintain a per-lock 'int id' member: the id of the
    lock anyway equals to its index in the bank's array plus the bank's
    base_id.
    Remove this per-lock id member too, and instead use a simple pointers
    arithmetic to derive it.
    
    As a result of this change, hwspinlocks drivers are now simpler and smaller
    (about %20 code reduction) and the memory footprint of the hwspinlock
    framework is reduced.
    Signed-off-by: default avatarOhad Ben-Cohen <ohad@wizery.com>
    300bab97
hwspinlock.txt 12.1 KB