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authorTakashi Iwai <tiwai@suse.de>2018-03-12 17:30:38 +0100
committerTakashi Iwai <tiwai@suse.de>2018-03-12 17:30:38 +0100
commitdb45dc9540ea4864bb9d22eed30d3e70ed5d56d4 (patch)
treec611d75097036ff464e9af31aa729e34c863ec93 /drivers/clocksource/arc_timer.c
parent40088dc4e1ead7df31728c73f5b51d71da18831d (diff)
parenta3e39ed1f40e14f24bec0f91c4fa0408fb6c4d02 (diff)
downloadlinux-db45dc9540ea4864bb9d22eed30d3e70ed5d56d4.tar.gz
linux-db45dc9540ea4864bb9d22eed30d3e70ed5d56d4.tar.xz
Merge tag 'asoc-fix-v4.16-rc5' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v4.16 This is a fairly standard collection of fixes, there's no changes to the core here just a bunch of small device specific changes for single drivers plus an update to the MAINTAINERS file for the sgl5000.
Diffstat (limited to 'drivers/clocksource/arc_timer.c')
-rw-r--r--drivers/clocksource/arc_timer.c11
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/clocksource/arc_timer.c b/drivers/clocksource/arc_timer.c
index 4927355f9cbe..471b428d8034 100644
--- a/drivers/clocksource/arc_timer.c
+++ b/drivers/clocksource/arc_timer.c
@@ -251,9 +251,14 @@ static irqreturn_t timer_irq_handler(int irq, void *dev_id)
int irq_reenable = clockevent_state_periodic(evt);
/*
- * Any write to CTRL reg ACks the interrupt, we rewrite the
- * Count when [N]ot [H]alted bit.
- * And re-arm it if perioid by [I]nterrupt [E]nable bit
+ * 1. ACK the interrupt
+ * - For ARC700, any write to CTRL reg ACKs it, so just rewrite
+ * Count when [N]ot [H]alted bit.
+ * - For HS3x, it is a bit subtle. On taken count-down interrupt,
+ * IP bit [3] is set, which needs to be cleared for ACK'ing.
+ * The write below can only update the other two bits, hence
+ * explicitly clears IP bit
+ * 2. Re-arm interrupt if periodic by writing to IE bit [0]
*/
write_aux_reg(ARC_REG_TIMER0_CTRL, irq_reenable | TIMER_CTRL_NH);