We discoverd that the state of BCLK on, LRCLK off and SD_MODE on
may cause the speaker melting issue. Removing LRCLK while BCLK
is present can cause unexpected output behavior including a large
DC output voltage as described in the Max98357a datasheet.
In order to:
1. prevent BCLK from turning on by other component.
2. keep BCLK and LRCLK being present at the same time
This patch adjusts the device tree to allow BCLK to switch
to GPIO func before LRCLK output, and switch back during
LRCLK is output.
Signed-off-by: Judy Hsiao <[email protected]>
---
.../boot/dts/rockchip/rk3399-gru-scarlet.dtsi | 10 ++++++++
arch/arm64/boot/dts/rockchip/rk3399.dtsi | 25 ++++++++++++++++++-
2 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet.dtsi
index 913d845eb51a..df1647e9d487 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399-gru-scarlet.dtsi
@@ -766,6 +766,16 @@ &i2s0_8ch_bus {
<4 RK_PA0 1 &pcfg_pull_none_6ma>;
};
+&i2s0_8ch_bus_bclk_off {
+ rockchip,pins =
+ <3 RK_PD0 RK_FUNC_GPIO &pcfg_pull_none_6ma>,
+ <3 RK_PD1 1 &pcfg_pull_none_6ma>,
+ <3 RK_PD2 1 &pcfg_pull_none_6ma>,
+ <3 RK_PD3 1 &pcfg_pull_none_6ma>,
+ <3 RK_PD7 1 &pcfg_pull_none_6ma>,
+ <4 RK_PA0 1 &pcfg_pull_none_6ma>;
+};
+
/* there is no external pull up, so need to set this pin pull up */
&sdmmc_cd_pin {
rockchip,pins = <1 RK_PB3 RK_FUNC_GPIO &pcfg_pull_up>;
diff --git a/arch/arm64/boot/dts/rockchip/rk3399.dtsi b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
index fbd0346624e6..311c8394cc84 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399.dtsi
@@ -1662,8 +1662,9 @@ i2s0: i2s@ff880000 {
dma-names = "tx", "rx";
clock-names = "i2s_clk", "i2s_hclk";
clocks = <&cru SCLK_I2S0_8CH>, <&cru HCLK_I2S0_8CH>;
- pinctrl-names = "default";
+ pinctrl-names = "bclk_on", "bclk_off";
pinctrl-0 = <&i2s0_8ch_bus>;
+ pinctrl-1 = <&i2s0_8ch_bus_bclk_off>;
power-domains = <&power RK3399_PD_SDIOAUDIO>;
#sound-dai-cells = <0>;
status = "disabled";
@@ -2407,6 +2408,19 @@ i2s0_8ch_bus: i2s0-8ch-bus {
<3 RK_PD7 1 &pcfg_pull_none>,
<4 RK_PA0 1 &pcfg_pull_none>;
};
+
+ i2s0_8ch_bus_bclk_off: i2s0-8ch-bus-bclk-off {
+ rockchip,pins =
+ <3 RK_PD0 RK_FUNC_GPIO &pcfg_pull_none>,
+ <3 RK_PD1 1 &pcfg_pull_none>,
+ <3 RK_PD2 1 &pcfg_pull_none>,
+ <3 RK_PD3 1 &pcfg_pull_none>,
+ <3 RK_PD4 1 &pcfg_pull_none>,
+ <3 RK_PD5 1 &pcfg_pull_none>,
+ <3 RK_PD6 1 &pcfg_pull_none>,
+ <3 RK_PD7 1 &pcfg_pull_none>,
+ <4 RK_PA0 1 &pcfg_pull_none>;
+ };
};
i2s1 {
@@ -2418,6 +2432,15 @@ i2s1_2ch_bus: i2s1-2ch-bus {
<4 RK_PA6 1 &pcfg_pull_none>,
<4 RK_PA7 1 &pcfg_pull_none>;
};
+
+ i2s1_2ch_bus_bclk_off: i2s1-2ch-bus-bclk-off {
+ rockchip,pins =
+ <4 RK_PA3 RK_FUNC_GPIO &pcfg_pull_none>,
+ <4 RK_PA4 1 &pcfg_pull_none>,
+ <4 RK_PA5 1 &pcfg_pull_none>,
+ <4 RK_PA6 1 &pcfg_pull_none>,
+ <4 RK_PA7 1 &pcfg_pull_none>;
+ };
};
sdio0 {
--
2.37.0.rc0.161.g10f37bed90-goog
On Fri, Jul 8, 2022 at 1:07 AM Judy Hsiao <[email protected]> wrote:
>
> We discoverd that the state of BCLK on, LRCLK off and SD_MODE on
super-nit: s/discoverd/discovered/
(If this is the only issue, perhaps Heiko can fix that when applying.)
> may cause the speaker melting issue. Removing LRCLK while BCLK
> is present can cause unexpected output behavior including a large
> DC output voltage as described in the Max98357a datasheet.
>
> In order to:
> 1. prevent BCLK from turning on by other component.
> 2. keep BCLK and LRCLK being present at the same time
>
> This patch adjusts the device tree to allow BCLK to switch
> to GPIO func before LRCLK output, and switch back during
> LRCLK is output.
>
> Signed-off-by: Judy Hsiao <[email protected]>
IIUC, it's not guaranteed everyone is using max98357a on this I2S
channel, but I suppose this change is still safe anyway? Or if this is
expected only for Gru-related boards, we could override the i2s node
settings in rk3399-gru.dtsi or similar.
Anyway, I think this is right:
Reviewed-by: Brian Norris <[email protected]>
On Fri, 8 Jul 2022 08:07:26 +0000, Judy Hsiao wrote:
> We discoverd that the state of BCLK on, LRCLK off and SD_MODE on
> may cause the speaker melting issue. Removing LRCLK while BCLK
> is present can cause unexpected output behavior including a large
> DC output voltage as described in the Max98357a datasheet.
>
> In order to:
> 1. prevent BCLK from turning on by other component.
> 2. keep BCLK and LRCLK being present at the same time
>
> [...]
Applied, thanks!
[1/1] arm64: dts: rk3399: i2s: switch BCLK to GPIO
commit: 91419ae0420f0c91a326655d687b740826d0a3f9
Best regards,
--
Heiko Stuebner <[email protected]>