[PATCH 43/49] mfd: qcom-pm8008: Enable mask_writeonly flag for irq chip

From: Aidan MacDonald
Date: Mon Jun 20 2022 - 16:11:36 EST


The PM8008 has separate set and clear registers for controlling
its interrupt masks. These are likely volatile registers which
read as 0, and writing a '1' bit sets or clears the corresponding
bit in the mask register.

The PM8008's regmap config doesn't enable a cache, so all register
access is already volatile. Adding the mask_writeonly flag should
reduce bus traffic by avoiding a read-modify-write on the mask
set/clear registers.

Signed-off-by: Aidan MacDonald <aidanmacdonald.0x0@xxxxxxxxx>
---
drivers/mfd/qcom-pm8008.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/mfd/qcom-pm8008.c b/drivers/mfd/qcom-pm8008.c
index 7bc6becfe7f4..c778f2f87a17 100644
--- a/drivers/mfd/qcom-pm8008.c
+++ b/drivers/mfd/qcom-pm8008.c
@@ -141,6 +141,7 @@ static struct regmap_irq_chip pm8008_irq_chip = {
.status_base = PM8008_STATUS_BASE,
.mask_base = PM8008_MASK_BASE,
.unmask_base = PM8008_UNMASK_BASE,
+ .mask_writeonly = true,
.ack_base = PM8008_ACK_BASE,
.config_base = pm8008_config_regs,
.num_config_bases = ARRAY_SIZE(pm8008_config_regs),
--
2.35.1