spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq
authorSubbaraman Narayanamurthy <subbaram@codeaurora.org>
Fri, 30 Sep 2022 00:50:13 +0000 (17:50 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 30 Sep 2022 12:33:23 +0000 (14:33 +0200)
commitb6c1761721193c52234e3ed048e4d16ab527bb74
tree2cc9d6976ffbc0a93d4928931466f4ed8a780297
parentabb9088b3a39cfec1321e93170ee3c0c1255fd9d
spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq

Currently, cleanup_irq() is invoked when a peripheral's interrupt
fires and there is no mapping present in the interrupt domain of
spmi interrupt controller.

The cleanup_irq clears the arbiter bit, clears the pmic interrupt
and disables it at the pmic in that order. The last disable in
cleanup_irq races with request_irq() in that it stomps over the
enable issued by request_irq. Fix this by not writing to the pmic
in cleanup_irq. The latched bit will be left set in the pmic,
which will not send us more interrupts even if the enable bit
stays enabled.

When a client wants to request an interrupt, use the activate
callback on the irq_domain to clear latched bit. This ensures
that the latched, if set due to the above changes in cleanup_irq
or when the bootloader leaves it set, gets cleaned up, paving way
for upcoming interrupts to trigger.

With this, there is a possibility of unwanted triggering of
interrupt right after the latched bit is cleared - the interrupt
may be left enabled too. To avoid that, clear the enable first
followed by clearing the latched bit in the activate callback.

Fixes: 6bc546e71e50 ("spmi: pmic-arb: cleanup unrequested irqs")
Fixes: 02abec3616c1 ("spmi: pmic-arb: rename pa_xx to pmic_arb_xx and other cleanup")
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>
[collinsd@codeaurora.org: fix merge conflict]
Signed-off-by: David Collins <collinsd@codeaurora.org>
Signed-off-by: Fenglin Wu <quic_fenglinw@quicinc.com>
Link: https://lore.kernel.org/r/1655004286-11493-4-git-send-email-quic_fenglinw@quicinc.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20220930005019.2663064-5-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/spmi/spmi-pmic-arb.c