[PATCH 02/12] ASoC: cs42l42: Add bitclock frequency argument to cs42l42_pll_config()

From: Richard Fitzgerald <rf@opensource.cirrus.com>
To: <broonie@kernel.org>
Cc: <alsa-devel@alsa-project.org>, <linux-kernel@vger.kernel.org>,
	<patches@opensource.cirrus.com>,
	Richard Fitzgerald <rf@opensource.cirrus.com>
Subject: [PATCH 02/12] ASoC: cs42l42: Add bitclock frequency argument to cs42l42_pll_config()
Date: Fri, 19 Aug 2022 13:52:20 +0100	[thread overview]
Message-ID: <20220819125230.42731-3-rf@opensource.cirrus.com> (raw)
In-Reply-To: <20220819125230.42731-1-rf@opensource.cirrus.com>

Clean up the handling of bitclock frequency by keeping all the logic
in cs42l42_pcm_hw_params(), which then simply passes the frequency as
an argument to cs42l42_pll_config().

The previous code had become clunky as a legacy of earlier versions of
the clock handling. The logic was split across cs42l42_pcm_hw_params()
and cs42l42_pll_config(), with the params-derived bclk stashed in
struct cs42l42_private only to pass it to cs42l42_pll_config().

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs42l42.c | 32 ++++++++++++++++----------------
 sound/soc/codecs/cs42l42.h |  1 -
 2 files changed, 16 insertions(+), 17 deletions(-)

diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index 440d414efe0a..1745b83310ac 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -649,18 +649,12 @@ static const struct cs42l42_pll_params pll_ratio_table[] = {
 	{ 24576000, 1, 0x03, 0x40, 0x000000, 0x03, 0x10, 12288000, 128, 1}
 };
 
-static int cs42l42_pll_config(struct snd_soc_component *component)
+static int cs42l42_pll_config(struct snd_soc_component *component, unsigned int clk)
 {
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
 	int i;
-	u32 clk;
 	u32 fsync;
 
-	if (!cs42l42->sclk)
-		clk = cs42l42->bclk;
-	else
-		clk = cs42l42->sclk;
-
 	/* Don't reconfigure if there is an audio stream running */
 	if (cs42l42->stream_use) {
 		if (pll_ratio_table[cs42l42->pll_config].sclk == clk)
@@ -897,19 +891,25 @@ static int cs42l42_pcm_hw_params(struct snd_pcm_substream *substream,
 	unsigned int width = (params_width(params) / 8) - 1;
 	unsigned int slot_width = 0;
 	unsigned int val = 0;
+	unsigned int bclk;
 	int ret;
 
 	cs42l42->srate = params_rate(params);
 
-	/*
-	 * Assume 24-bit samples are in 32-bit slots, to prevent SCLK being
-	 * more than assumed (which would result in overclocking).
-	 */
-	if (params_width(params) == 24)
-		slot_width = 32;
+	if (cs42l42->sclk) {
+		/* machine driver has set the SCLK */
+		bclk = cs42l42->sclk;
+	} else {
+		/*
+		 * Assume 24-bit samples are in 32-bit slots, to prevent SCLK being
+		 * more than assumed (which would result in overclocking).
+		 */
+		if (params_width(params) == 24)
+			slot_width = 32;
 
-	/* I2S frame always has multiple of 2 channels */
-	cs42l42->bclk = snd_soc_tdm_params_to_bclk(params, slot_width, 0, 2);
+		/* I2S frame always has multiple of 2 channels */
+		bclk = snd_soc_tdm_params_to_bclk(params, slot_width, 0, 2);
+	}
 
 	switch (substream->stream) {
 	case SNDRV_PCM_STREAM_CAPTURE:
@@ -949,7 +949,7 @@ static int cs42l42_pcm_hw_params(struct snd_pcm_substream *substream,
 		break;
 	}
 
-	ret = cs42l42_pll_config(component);
+	ret = cs42l42_pll_config(component, bclk);
 	if (ret)
 		return ret;
 
diff --git a/sound/soc/codecs/cs42l42.h b/sound/soc/codecs/cs42l42.h
index 50299c9f283a..b4ba1467c558 100644
--- a/sound/soc/codecs/cs42l42.h
+++ b/sound/soc/codecs/cs42l42.h
@@ -30,7 +30,6 @@ struct  cs42l42_private {
 	struct snd_soc_jack *jack;
 	struct mutex irq_lock;
 	int pll_config;
-	int bclk;
 	u32 sclk;
 	u32 srate;
 	u8 plug_state;
-- 
2.30.2

