From: Tony Lindgren <tony@atomide.com>
To: Lee Jones <lee.jones@linaro.org>
Cc: linux-kernel@vger.kernel.org,
Carl Philipp Klemm <philipp@uvos.xyz>,
Laxminath Kasam <lkasam@codeaurora.org>,
Merlijn Wajer <merlijn@wizzup.org>,
Mark Brown <broonie@kernel.org>, Pavel Machek <pavel@ucw.cz>,
Sebastian Reichel <sre@kernel.org>,
Tim Harvey <tharvey@gateworks.com>
Subject: [PATCH] mfd: cpcap: Fix interrupt regression with regmap clear_ack
Date: Wed, 11 Nov 2020 19:06:13 +0200 [thread overview]
Message-ID: <20201111170613.46057-1-tony@atomide.com> (raw)
With commit 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack
registers"), the cpcap interrupts are no longer getting acked properly
leading to a very unresponsive device with CPUs fully loaded spinning
in the threaded IRQ handlers.
To me it looks like the clear_ack commit above actually fixed a long
standing bug in regmap_irq_thread() where we unconditionally acked the
interrupts earlier without considering ack_invert. And the issue with
cpcap started happening as we now also consider ack_invert.
Tim Harvey <tharvey@gateworks.com> tried to fix this issue earlier with
"[PATCH v2] regmap: irq: fix ack-invert", but the reading of the ack
register was considered unnecessary for just ack_invert, and we did not
have clear_ack available yet. As the cpcap irqs worked both with and
without ack_invert earlier because of the unconditional ack, the
problem remained hidden until now.
Also, looks like the earlier v3.0.8 based Motorola Android Linux kernel
does clear_ack style read-clear-write with "ireg_val & ~mreg_val" instead
of just ack_invert style write. So let's switch cpcap to use clear_ack
to fix the issue.
Fixes: 3a6f0fb7b8eb ("regmap: irq: Add support to clear ack registers")
Cc: Carl Philipp Klemm <philipp@uvos.xyz>
Cc: Laxminath Kasam <lkasam@codeaurora.org>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
drivers/mfd/motorola-cpcap.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/mfd/motorola-cpcap.c b/drivers/mfd/motorola-cpcap.c
--- a/drivers/mfd/motorola-cpcap.c
+++ b/drivers/mfd/motorola-cpcap.c
@@ -97,7 +97,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
.ack_base = CPCAP_REG_MI1,
.mask_base = CPCAP_REG_MIM1,
.use_ack = true,
- .ack_invert = true,
+ .clear_ack = true,
},
{
.name = "cpcap-m2",
@@ -106,7 +106,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
.ack_base = CPCAP_REG_MI2,
.mask_base = CPCAP_REG_MIM2,
.use_ack = true,
- .ack_invert = true,
+ .clear_ack = true,
},
{
.name = "cpcap1-4",
@@ -115,7 +115,7 @@ static struct regmap_irq_chip cpcap_irq_chip[CPCAP_NR_IRQ_CHIPS] = {
.ack_base = CPCAP_REG_INT1,
.mask_base = CPCAP_REG_INTM1,
.use_ack = true,
- .ack_invert = true,
+ .clear_ack = true,
},
};
--
2.29.2
next reply other threads:[~2020-11-11 17:06 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-11 17:06 Tony Lindgren [this message]
2020-11-13 10:21 ` [PATCH] mfd: cpcap: Fix interrupt regression with regmap clear_ack Lee Jones
2020-11-13 22:06 ` Tim Harvey
2020-11-15 8:43 ` Tony Lindgren
2020-11-16 20:45 ` Tim Harvey
2020-11-16 18:59 ` Mark Brown
2020-11-16 20:43 ` Tim Harvey
2020-11-16 21:14 ` Mark Brown
2020-11-15 17:31 ` Pavel Machek
2020-11-17 8:25 ` Lee Jones
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201111170613.46057-1-tony@atomide.com \
--to=tony@atomide.com \
--cc=broonie@kernel.org \
--cc=lee.jones@linaro.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lkasam@codeaurora.org \
--cc=merlijn@wizzup.org \
--cc=pavel@ucw.cz \
--cc=philipp@uvos.xyz \
--cc=sre@kernel.org \
--cc=tharvey@gateworks.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).