linux-kernel - [PATCH 3/3] ASoC: cs35l56: In secure mode skip SHUTDOWN and RESET around fw download

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Message-ID: <20230518150250.1121006-4-rf@opensource.cirrus.com>
Date:   Thu, 18 May 2023 16:02:50 +0100
From:   Richard Fitzgerald <rf@...nsource.cirrus.com>
To:     <broonie@...nel.org>
CC:     <alsa-devel@...a-project.org>, <linux-kernel@...r.kernel.org>,
        <patches@...nsource.cirrus.com>,
        Simon Trimmer <simont@...nsource.cirrus.com>,
        Richard Fitzgerald <rf@...nsource.cirrus.com>
Subject: [PATCH 3/3] ASoC: cs35l56: In secure mode skip SHUTDOWN and RESET around fw download

From: Simon Trimmer <simont@...nsource.cirrus.com>

If the device is in secure mode it's unnecessary to send a SHUTDOWN and
SYSTEM_RESET around the firmware download. It could only be patching
insecure tunings. A tuning patch doesn't need a SHUTDOWN and only needs
a REINIT afterwards. This will reduce the overhead of exiting system
suspend in secure mode.

Signed-off-by: Simon Trimmer <simont@...nsource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@...nsource.cirrus.com>
---
 include/sound/cs35l56.h    |  1 +
 sound/soc/codecs/cs35l56.c | 47 ++++++++++++++++++++++++++++++--------
 2 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/include/sound/cs35l56.h b/include/sound/cs35l56.h
index 002042b1c73c..1f9713d7ca76 100644
--- a/include/sound/cs35l56.h
+++ b/include/sound/cs35l56.h
@@ -223,6 +223,7 @@
 
 #define CS35L56_MBOX_CMD_AUDIO_PLAY			0x0B000001
 #define CS35L56_MBOX_CMD_AUDIO_PAUSE			0x0B000002
+#define CS35L56_MBOX_CMD_AUDIO_REINIT			0x0B000003
 #define CS35L56_MBOX_CMD_HIBERNATE_NOW			0x02000001
 #define CS35L56_MBOX_CMD_WAKEUP				0x02000002
 #define CS35L56_MBOX_CMD_PREVENT_AUTO_HIBERNATE		0x02000003
diff --git a/sound/soc/codecs/cs35l56.c b/sound/soc/codecs/cs35l56.c
index 255c442308f2..3c07bd1e959e 100644
--- a/sound/soc/codecs/cs35l56.c
+++ b/sound/soc/codecs/cs35l56.c
@@ -825,19 +825,23 @@ static void cs35l56_system_reset(struct cs35l56_private *cs35l56)
 	regcache_cache_only(cs35l56->regmap, false);
 }
 
-static void cs35l56_dsp_work(struct work_struct *work)
+static void cs35l56_secure_patch(struct cs35l56_private *cs35l56)
+{
+	int ret;
+
+	/* Use wm_adsp to load and apply the firmware patch and coefficient files */
+	ret = wm_adsp_power_up(&cs35l56->dsp);
+	if (ret)
+		dev_dbg(cs35l56->dev, "%s: wm_adsp_power_up ret %d\n", __func__, ret);
+	else
+		cs35l56_mbox_send(cs35l56, CS35L56_MBOX_CMD_AUDIO_REINIT);
+}
+
+static void cs35l56_patch(struct cs35l56_private *cs35l56)
 {
-	struct cs35l56_private *cs35l56 = container_of(work,
-						       struct cs35l56_private,
-						       dsp_work);
 	unsigned int reg;
 	unsigned int val;
-	int ret = 0;
-
-	if (!cs35l56->init_done)
-		return;
-
-	pm_runtime_get_sync(cs35l56->dev);
+	int ret;
 
 	/*
 	 * Disable SoundWire interrupts to prevent race with IRQ work.
@@ -910,6 +914,29 @@ static void cs35l56_dsp_work(struct work_struct *work)
 		sdw_write_no_pm(cs35l56->sdw_peripheral, CS35L56_SDW_GEN_INT_MASK_1,
 				CS35L56_SDW_INT_MASK_CODEC_IRQ);
 	}
+}
+
+static void cs35l56_dsp_work(struct work_struct *work)
+{
+	struct cs35l56_private *cs35l56 = container_of(work,
+						       struct cs35l56_private,
+						       dsp_work);
+
+	if (!cs35l56->init_done)
+		return;
+
+	pm_runtime_get_sync(cs35l56->dev);
+
+	/*
+	 * When the device is running in secure mode the firmware files can
+	 * only contain insecure tunings and therefore we do not need to
+	 * shutdown the firmware to apply them and can use the lower cost
+	 * reinit sequence instead.
+	 */
+	if (cs35l56->secured)
+		cs35l56_secure_patch(cs35l56);
+	else
+		cs35l56_patch(cs35l56);
 
 	pm_runtime_mark_last_busy(cs35l56->dev);
 	pm_runtime_put_autosuspend(cs35l56->dev);
-- 
2.30.2