The internal accounting uses 'timespec' based time stamps, which is
slightly inefficient and also problematic once we get to the time_t
overflow in 2038.
When communicating to the firmware, we even get an open-coded 64-bit
division that prevents the code from being build-tested on 32-bit
architectures and is inefficient due to the double conversion from
64-bit nanoseconds to seconds+nanoseconds and then microseconds.
This changes the code to use ktime_t instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
I was trying to understand this code while working on a warning
fix and the locking made no sense: spin_lock_irqsave() is pointless
when run inside of an interrupt handler or nested inside of another
spin_lock_irq() or spin_lock_irqsave().
Here it turned out that the comment above the function is wrong,
as both recv_ishtp_cl_msg_dma() and recv_ishtp_cl_msg() can in fact
be called from a work queue rather than an ISR, so we do have to
use the irqsave() version once.
This fixes the comments accordingly, removes the misleading 'dev_flags'
variable and modifies the inner spinlock to not use 'irqsave'.
No functional change is intended, this is just for readability and
it slightly simplifies the object code.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
gcc points out an uninialized pointer dereference that could happen
if we ever get to recv_ishtp_cl_msg_dma() or recv_ishtp_cl_msg()
with an empty &dev->read_list:
drivers/hid/intel-ish-hid/ishtp/client.c: In function 'recv_ishtp_cl_msg_dma':
drivers/hid/intel-ish-hid/ishtp/client.c:1049:3: error: 'cl' may be used uninitialized in this function [-Werror=maybe-uninitialized]
The warning only appeared in very few randconfig builds, as the
spinlocks tend to prevent gcc from tracing the variables. I only
saw it in configurations that had neither SMP nor LOCKDEP enabled.
As we can see, we only enter the case if 'complete_rb' is non-NULL,
and then 'cl' is known to point to complete_rb->cl. Adding another
initialization to the same pointer is harmless here and makes it
clear to the compiler that the behavior is well-defined.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The ISH transport layer (ishtp) is a bi-directional protocol implemented
on the top of PCI based inter processor communication layer. This layer
offers:
- Connection management
- Flow control with the firmware
- Multiple client sessions
- Client message transfer
- Client message reception
- DMA for RX and TX for fast data transfer
Refer to Documentation/hid/intel-ish-hid.txt for
overview of the functionality implemented in this layer.
Original-author: Daniel Drubin <daniel.drubin@intel.com>
Reviewed-and-tested-by: Ooi, Joyce <joyce.ooi@intel.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Rann Bar-On <rb6@duke.edu>
Tested-by: Atri Bhattacharya <badshah400@aim.com>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
