[ Upstream commit dc171114926ec390ab90f46534545420ec03e458 ]
It is not particularly useful to release locks (the EC mutex and the
ACPI global lock, if present) and re-acquire them immediately thereafter
during EC address space accesses in acpi_ec_space_handler().
First, releasing them for a while before grabbing them again does not
really help anyone because there may not be enough time for another
thread to acquire them.
Second, if another thread successfully acquires them and carries out
a new EC write or read in the middle if an operation region access in
progress, it may confuse the EC firmware, especially after the burst
mode has been enabled.
Finally, manipulating the locks after writing or reading every single
byte of data is overhead that it is better to avoid.
Accordingly, modify the code to carry out EC address space accesses
entirely without releasing the locks.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patch.msgid.link/12473338.O9o76ZdvQC@rjwysocki.net
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c4bd7f1d78340e63de4d073fd3dbe5391e2996e5 ]
If an error code other than EINVAL, ENODEV or ETIME is returned
by acpi_ec_read() / acpi_ec_write(), then AE_OK is incorrectly
returned by acpi_ec_space_handler().
Fix this by only returning AE_OK on success, and return AE_ERROR
otherwise.
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f6f172dc6a6d7775b2df6adfd1350700e9a847ec ]
When a multi-byte address space access is requested, acpi_ec_read()/
acpi_ec_write() is being called multiple times.
Abort such operations if a single call to acpi_ec_read() /
acpi_ec_write() fails, as the data read from / written to the EC
might be incomplete.
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
