linux/drivers/platform
Stephen Boyd 427fada620 platform/x86: intel_scu_ipc: Check status upon timeout in ipc_wait_for_interrupt()
It's possible for the completion in ipc_wait_for_interrupt() to timeout,
simply because the interrupt was delayed in being processed. A timeout
in itself is not an error. This driver should check the status register
upon a timeout to ensure that scheduling or interrupt processing delays
don't affect the outcome of the IPC return value.

 CPU0                                                   SCU
 ----                                                   ---
 ipc_wait_for_interrupt()
  wait_for_completion_timeout(&scu->cmd_complete)
  [TIMEOUT]                                             status[IPC_STATUS_BUSY]=0

Fix this problem by reading the status bit in all cases, regardless of
the timeout. If the completion times out, we'll assume the problem was
that the IPC_STATUS_BUSY bit was still set, but if the status bit is
cleared in the meantime we know that we hit some scheduling delay and we
should just check the error bit.

Cc: Prashant Malani <pmalani@chromium.org>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Fixes: ed12f295bf ("ipc: Added support for IPC interrupt mode")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20230913212723.3055315-3-swboyd@chromium.org
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2023-09-18 15:14:53 +02:00
..
chrome USB / Thunderbolt / PHY driver update for 6.6-rc1 2023-09-01 09:23:34 -07:00
goldfish platform: goldfish: pipe: Use platform_get_irq() to get the interrupt 2022-03-18 13:55:21 +01:00
loongarch platform/loongarch: laptop: Fix possible UAF and simplify generic_acpi_laptop_init() 2022-10-29 16:29:31 +08:00
mellanox platform/mellanox: NVSW_SN2201 should depend on ACPI 2023-09-11 13:21:46 +02:00
mips platform/mips: Adjust Kconfig to keep consistency 2022-12-08 11:51:52 +01:00
olpc platform/olpc: olpc-xo175-ec: Use SPI device ID data to bind device 2023-03-20 14:43:35 +01:00
surface platform-drivers-x86 for v6.5-1 2023-06-30 14:50:00 -07:00
x86 platform/x86: intel_scu_ipc: Check status upon timeout in ipc_wait_for_interrupt() 2023-09-18 15:14:53 +02:00
Kconfig platform/mips: Adjust Kconfig to keep consistency 2022-12-08 11:51:52 +01:00
Makefile LoongArch: Add ACPI-based generic laptop driver 2022-10-12 16:36:20 +08:00