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arm64: dts: imx8-apalis: add clock configuration for 44.1 kHz hdmi audio

PATCH Applied Stefan Eichenberger 2 participants 2 messages Jan 20, 2025 – Feb 22, 2025

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Stefan Eichenberger

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PATCH 1/1 arm64: dts: imx8-apalis: add clock configuration for 44.1 kHz hdmi audio

From: Stefan Eichenberger <[email protected]>

Currently, HDMI audio cannot play sound at a 44.1 kHz sample rate due to a clock frequency mismatch. This update resolves the issue by allowing the sai driver to change the clock parent to AUDIO_PLL_1 when the sample rate is 44.1 kHz. It also ensures that AUDIO_PLL_1 operates at the correct frequency for this configuration.

Signed-off-by Stefan Eichenberger <[email protected]>

---
This patch is based on the following discussion:
https://lore.kernel.org/all/[email protected]/
We use the existing mechanisms and just add the missing clock configuration to our device tree.

 .../boot/dts/freescale/imx8-apalis-v1.1.dtsi     | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
arch/arm64/boot/dts/freescale/imx8-apalis-v1.1.dtsi +16 -0
index a3fc945aea16..dbea1eefdeec 100644
@@ -790,6 +790,22 @@ &sai1 {
 	status = "okay";
 };
 
+/* Apalis HDMI Audio */
+&sai5 {
+	assigned-clocks = <&acm IMX_ADMA_ACM_SAI5_MCLK_SEL>,
+			  <&acm IMX_ADMA_ACM_AUD_CLK1_SEL>,
+			  <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_PLL>,
+			  <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_SLV_BUS>,
+			  <&clk IMX_SC_R_AUDIO_PLL_0 IMX_SC_PM_CLK_MST_BUS>,
+			  <&clk IMX_SC_R_AUDIO_PLL_1 IMX_SC_PM_CLK_PLL>,
+			  <&clk IMX_SC_R_AUDIO_PLL_1 IMX_SC_PM_CLK_SLV_BUS>,
+			  <&clk IMX_SC_R_AUDIO_PLL_1 IMX_SC_PM_CLK_MST_BUS>,
+			  <&sai5_lpcg 0>;
+	assigned-clock-parents = <&aud_pll_div0_lpcg 0>, <&aud_rec1_lpcg 0>;
+	assigned-clock-rates = <0>, <0>, <786432000>, <49152000>, <12288000>,
+			       <722534400>, <45158400>, <11289600>, <49152000>;
+};
+
 /* TODO: Apalis SATA1 */
 
 /* Apalis SPDIF1 */
Signature · 1 line
2.45.2
Applied
#1 lore raw
Quoted 9 lines · Stefan Eichenberger

From: Stefan Eichenberger <[email protected]>

Currently, HDMI audio cannot play sound at a 44.1 kHz sample rate due to a clock frequency mismatch. This update resolves the issue by allowing the sai driver to change the clock parent to AUDIO_PLL_1 when the sample rate is 44.1 kHz. It also ensures that AUDIO_PLL_1 operates at the correct frequency for this configuration.

Signed-off-by Stefan Eichenberger <[email protected]>

Applied, thanks!