linux-kernel - [PATCH 3/3] ASoC: cs35l45: Prevents spinning during runtime suspend

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Message-ID: <20231206160318.1255034-4-rriveram@opensource.cirrus.com>
Date:   Wed, 6 Dec 2023 10:03:18 -0600
From:   Ricardo Rivera-Matos <rriveram@...nsource.cirrus.com>
To:     James Schulman <james.schulman@...rus.com>,
        David Rhodes <david.rhodes@...rus.com>,
        Lucas Tanure <tanureal@...nsource.cirrus.com>,
        Richard Fitzgerald <rf@...nsource.cirrus.com>,
        Liam Girdwood <lgirdwood@...il.com>,
        Mark Brown <broonie@...nel.org>,
        Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>
CC:     Ricardo Rivera-Matos <rriveram@...nsource.cirrus.com>,
        Charles Keepax <ckeepax@...nsource.cirrus.com>,
        <alsa-devel@...a-project.org>, <patches@...nsource.cirrus.com>,
        <linux-kernel@...r.kernel.org>
Subject: [PATCH 3/3] ASoC: cs35l45: Prevents spinning during runtime suspend

Masks the "DSP Virtual Mailbox 2 write" interrupt when before
issuing the hibernate command to the DSP. The interrupt is
unmasked when exiting runtime suspend as it is required for
DSP operation.

Without this change the DSP fires an interrupt when hibernating
causing the system spin between runtime suspend and runtime
resume.

Signed-off-by: Ricardo Rivera-Matos <rriveram@...nsource.cirrus.com>
Acked-by: Charles Keepax <ckeepax@...nsource.cirrus.com>
---
 sound/soc/codecs/cs35l45.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/soc/codecs/cs35l45.c b/sound/soc/codecs/cs35l45.c
index 28f76fccf277..44c221745c3b 100644
--- a/sound/soc/codecs/cs35l45.c
+++ b/sound/soc/codecs/cs35l45.c
@@ -947,6 +947,8 @@ static int cs35l45_enter_hibernate(struct cs35l45_private *cs35l45)
 
 	cs35l45_setup_hibernate(cs35l45);
 
+	regmap_set_bits(cs35l45->regmap, CS35L45_IRQ1_MASK_2, CS35L45_DSP_VIRT2_MBOX_MASK);
+
 	// Don't wait for ACK since bus activity would wake the device
 	regmap_write(cs35l45->regmap, CS35L45_DSP_VIRT1_MBOX_1, CSPL_MBOX_CMD_HIBERNATE);
 
@@ -967,6 +969,8 @@ static int cs35l45_exit_hibernate(struct cs35l45_private *cs35l45)
 					  CSPL_MBOX_CMD_OUT_OF_HIBERNATE);
 			if (!ret) {
 				dev_dbg(cs35l45->dev, "Wake success at cycle: %d\n", j);
+				regmap_clear_bits(cs35l45->regmap, CS35L45_IRQ1_MASK_2,
+						 CS35L45_DSP_VIRT2_MBOX_MASK);
 				return 0;
 			}
 			usleep_range(100, 200);
-- 
2.34.1