Inheritance of HAL object is performed by composing a child structure of a
single parent structure located at offset 0 followed by new data members
and function pointers in the child structure.
For example,
struct child {
struct parent common;
int a_data_member;
void (*a_method)(struct child *c, int v);
};
HAL code assumes this layout when accessing child structures given a pointer
to a parent structure such that users write code like the following...
void child_method(struct *parent, int v) {
struct child * c = (struct child*)parent;
// do stuff with c
}
Code above will break if a member is added before "common" in "struct child".
This change adds comments that describe the restriction on the location of
parent HAL objects within a derived HAL object. HAL objects that already
have comments that describe the required location of parent objects are not
modified.
Change-Id: Ibe4300275286ef275b2097534c84f1029d761d87
Put stronger requirements on the vibrator API:
- vibratorOn must not be called if the vibrator is already called (requirement
on the caller);
- vibratorOff must cancel any ongoing vibration (requirement on the callee).
Change-Id: Ic2fcd29903bf5a11a19c731de355d19c06c4e0e2
Signed-off-by: David Wagner <david.wagner@intel.com>
Android's implementation of vibrator needs to be done inside a
hardware module, so that it can make a vendor implementation possible.
Hw module's name becomes vibrator.default.so.
This change is related to other changes in:
- frameworks/base
- hardware/libhardware_legacy
- device/generic/goldfish
- platform/build
Change-Id: I844279f5535289f079d412fdc44c5cb3c9c1130c
Author: Vincent Becker <vincentx.becker@intel.com>
Signed-off-by: Vincent Becker <vincentx.becker@intel.com>
Signed-off-by: Shuo Gao <shuo.gao@intel.com>
Signed-off-by: Bruce Beare <bruce.j.beare@intel.com>
Signed-off-by: Jack Ren <jack.ren@intel.com>
Signed-off-by: David Wagner <david.wagner@intel.com>
Author-tracking-BZ: 49760 94611
