* [PATCH 0/3] Add mclk0 clock source for SAI
@ 2019-05-28 13:20 Daniel Baluta
2019-05-28 13:21 ` [PATCH 1/3] ARM: dts: imx: Add mclk0 clock " Daniel Baluta
` (3 more replies)
0 siblings, 4 replies; 8+ messages in thread
From: Daniel Baluta @ 2019-05-28 13:20 UTC (permalink / raw)
To: robh+dt, shawnguo, timur, nicoleotsuka, broonie
Cc: mark.rutland, devicetree, alsa-devel, Xiubo.Lee, Daniel Baluta,
s.hauer, tiwai, linux-kernel, lgirdwood, dl-linux-imx, kernel,
festevam, linux-arm-kernel
This patch series brings together patches [1] and [2] which
introduce mclk0 clock source via DT.
mclk0..3 are the four clock sources options
of SAI's clock MUX.
mclk0 option selects:
- Bus Clock on i.MX8
- MCLK1 on i.MX6/7
Finally we also update the DT binding information for SAI clocks.
In [1] and [2] Nicolin had a very good point on the fact that
mclk0 might not be needed in the DT. Anyhow, there are two reasons
for which I think mlck0 should be added to DT:
1) SAI clock source select MUX is really part of the hardware
2) flexibility! We let DT tell us which is the option for MUX
option 0.
[1] lkml.org/lkml/2019/4/20/141
[2] lkml.org/lkml/2019/4/20/56
Daniel Baluta (2):
dt-bindings: sound: Clarify the usage of clocks in SAI
ASoC: fsl_sai: Read SAI clock source 0 from DT
Shengjiu Wang (1):
ARM: dts: imx: Add mclk0 clock for SAI
Documentation/devicetree/bindings/sound/fsl-sai.txt | 5 +++--
arch/arm/boot/dts/imx6sx.dtsi | 6 ++++--
arch/arm/boot/dts/imx6ul.dtsi | 9 ++++++---
arch/arm/boot/dts/imx7s.dtsi | 9 ++++++---
sound/soc/fsl/fsl_sai.c | 3 +--
5 files changed, 20 insertions(+), 12 deletions(-)
--
2.17.1
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^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH 1/3] ARM: dts: imx: Add mclk0 clock for SAI 2019-05-28 13:20 [PATCH 0/3] Add mclk0 clock source for SAI Daniel Baluta @ 2019-05-28 13:21 ` Daniel Baluta 2019-05-29 22:57 ` Nicolin Chen 2019-05-28 13:21 ` [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI Daniel Baluta ` (2 subsequent siblings) 3 siblings, 1 reply; 8+ messages in thread From: Daniel Baluta @ 2019-05-28 13:21 UTC (permalink / raw) To: robh+dt, shawnguo, timur, nicoleotsuka, broonie Cc: mark.rutland, devicetree, alsa-devel, Xiubo.Lee, Daniel Baluta, s.hauer, tiwai, linux-kernel, lgirdwood, dl-linux-imx, kernel, festevam, S.j. Wang, linux-arm-kernel From: Shengjiu Wang <shengjiu.wang@nxp.com> Audio MCLK source option is selected with a 4:1 MUX controller using MCLK Select bits in SAI xCR2 register. On imx6/7 mclk0 and mclk1 always point to the same clock source. Anyhow, this is no longer true for imx8. For this reason, we need to add mclk0 and handle it in a generic way in SAI driver. Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> --- arch/arm/boot/dts/imx6sx.dtsi | 6 ++++-- arch/arm/boot/dts/imx6ul.dtsi | 9 ++++++--- arch/arm/boot/dts/imx7s.dtsi | 9 ++++++--- 3 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/arm/boot/dts/imx6sx.dtsi b/arch/arm/boot/dts/imx6sx.dtsi index b16a123990a2..682207b5d868 100644 --- a/arch/arm/boot/dts/imx6sx.dtsi +++ b/arch/arm/boot/dts/imx6sx.dtsi @@ -1071,9 +1071,10 @@ reg = <0x021d4000 0x4000>; interrupts = <GIC_SPI 97 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6SX_CLK_SAI1_IPG>, + <&clks IMX6SX_CLK_SAI1>, <&clks IMX6SX_CLK_SAI1>, <&clks 0>, <&clks 0>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dma-names = "rx", "tx"; dmas = <&sdma 31 24 0>, <&sdma 32 24 0>; status = "disabled"; @@ -1090,9 +1091,10 @@ reg = <0x021dc000 0x4000>; interrupts = <GIC_SPI 98 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6SX_CLK_SAI2_IPG>, + <&clks IMX6SX_CLK_SAI2>, <&clks IMX6SX_CLK_SAI2>, <&clks 0>, <&clks 0>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dma-names = "rx", "tx"; dmas = <&sdma 33 24 0>, <&sdma 34 24 0>; status = "disabled"; diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi index bbf010c73336..e9691306f557 100644 --- a/arch/arm/boot/dts/imx6ul.dtsi +++ b/arch/arm/boot/dts/imx6ul.dtsi @@ -304,9 +304,10 @@ reg = <0x02028000 0x4000>; interrupts = <GIC_SPI 97 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6UL_CLK_SAI1_IPG>, + <&clks IMX6UL_CLK_SAI1>, <&clks IMX6UL_CLK_SAI1>, <&clks IMX6UL_CLK_DUMMY>, <&clks IMX6UL_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dmas = <&sdma 35 24 0>, <&sdma 36 24 0>; dma-names = "rx", "tx"; @@ -319,9 +320,10 @@ reg = <0x0202c000 0x4000>; interrupts = <GIC_SPI 98 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6UL_CLK_SAI2_IPG>, + <&clks IMX6UL_CLK_SAI2>, <&clks IMX6UL_CLK_SAI2>, <&clks IMX6UL_CLK_DUMMY>, <&clks IMX6UL_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dmas = <&sdma 37 24 0>, <&sdma 38 24 0>; dma-names = "rx", "tx"; @@ -334,9 +336,10 @@ reg = <0x02030000 0x4000>; interrupts = <GIC_SPI 24 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX6UL_CLK_SAI3_IPG>, + <&clks IMX6UL_CLK_SAI3>, <&clks IMX6UL_CLK_SAI3>, <&clks IMX6UL_CLK_DUMMY>, <&clks IMX6UL_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dmas = <&sdma 39 24 0>, <&sdma 40 24 0>; dma-names = "rx", "tx"; diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi index 106711d2c01b..c345a2e6d824 100644 --- a/arch/arm/boot/dts/imx7s.dtsi +++ b/arch/arm/boot/dts/imx7s.dtsi @@ -886,10 +886,11 @@ reg = <0x308a0000 0x10000>; interrupts = <GIC_SPI 95 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX7D_SAI1_IPG_CLK>, + <&clks IMX7D_SAI1_ROOT_CLK>, <&clks IMX7D_SAI1_ROOT_CLK>, <&clks IMX7D_CLK_DUMMY>, <&clks IMX7D_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dma-names = "rx", "tx"; dmas = <&sdma 8 24 0>, <&sdma 9 24 0>; status = "disabled"; @@ -901,10 +902,11 @@ reg = <0x308b0000 0x10000>; interrupts = <GIC_SPI 96 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX7D_SAI2_IPG_CLK>, + <&clks IMX7D_SAI2_ROOT_CLK>, <&clks IMX7D_SAI2_ROOT_CLK>, <&clks IMX7D_CLK_DUMMY>, <&clks IMX7D_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dma-names = "rx", "tx"; dmas = <&sdma 10 24 0>, <&sdma 11 24 0>; status = "disabled"; @@ -916,10 +918,11 @@ reg = <0x308c0000 0x10000>; interrupts = <GIC_SPI 50 IRQ_TYPE_LEVEL_HIGH>; clocks = <&clks IMX7D_SAI3_IPG_CLK>, + <&clks IMX7D_SAI3_ROOT_CLK>, <&clks IMX7D_SAI3_ROOT_CLK>, <&clks IMX7D_CLK_DUMMY>, <&clks IMX7D_CLK_DUMMY>; - clock-names = "bus", "mclk1", "mclk2", "mclk3"; + clock-names = "bus", "mclk0", "mclk1", "mclk2", "mclk3"; dma-names = "rx", "tx"; dmas = <&sdma 12 24 0>, <&sdma 13 24 0>; status = "disabled"; -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 1/3] ARM: dts: imx: Add mclk0 clock for SAI 2019-05-28 13:21 ` [PATCH 1/3] ARM: dts: imx: Add mclk0 clock " Daniel Baluta @ 2019-05-29 22:57 ` Nicolin Chen 0 siblings, 0 replies; 8+ messages in thread From: Nicolin Chen @ 2019-05-29 22:57 UTC (permalink / raw) To: Daniel Baluta Cc: mark.rutland, devicetree, alsa-devel, timur, Xiubo.Lee, festevam, s.hauer, tiwai, linux-kernel, robh+dt, lgirdwood, broonie, dl-linux-imx, kernel, shawnguo, S.j. Wang, linux-arm-kernel On Tue, May 28, 2019 at 01:21:00PM +0000, Daniel Baluta wrote: > From: Shengjiu Wang <shengjiu.wang@nxp.com> > > Audio MCLK source option is selected with a 4:1 MUX > controller using MCLK Select bits in SAI xCR2 register. > > On imx6/7 mclk0 and mclk1 always point to the same clock > source. Anyhow, this is no longer true for imx8. > > For this reason, we need to add mclk0 and handle it > in a generic way in SAI driver. > > Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> > --- > arch/arm/boot/dts/imx6sx.dtsi | 6 ++++-- > arch/arm/boot/dts/imx6ul.dtsi | 9 ++++++--- > arch/arm/boot/dts/imx7s.dtsi | 9 ++++++--- These are dtsi/dts files that have SAI missing mclk0: arch/arm/boot/dts/imx6ul.dtsi arch/arm/boot/dts/imx6sx.dtsi arch/arm/boot/dts/ls1021a.dtsi arch/arm/boot/dts/imx7s.dtsi arch/arm/boot/dts/vfxxx.dtsi arch/arm64/boot/dts/freescale/imx8mq.dtsi arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi arch/arm64/boot/dts/freescale/fsl-ls1012a.dtsi Would it be possible for you to update the others also? Thanks Nicolin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI 2019-05-28 13:20 [PATCH 0/3] Add mclk0 clock source for SAI Daniel Baluta 2019-05-28 13:21 ` [PATCH 1/3] ARM: dts: imx: Add mclk0 clock " Daniel Baluta @ 2019-05-28 13:21 ` Daniel Baluta 2019-06-14 20:00 ` Rob Herring 2019-05-28 13:21 ` [PATCH 3/3] ASoC: fsl_sai: Read SAI clock source 0 from DT Daniel Baluta 2019-05-29 23:03 ` [PATCH 0/3] Add mclk0 clock source for SAI Nicolin Chen 3 siblings, 1 reply; 8+ messages in thread From: Daniel Baluta @ 2019-05-28 13:21 UTC (permalink / raw) To: robh+dt, shawnguo, timur, nicoleotsuka, broonie Cc: mark.rutland, devicetree, alsa-devel, Xiubo.Lee, Daniel Baluta, s.hauer, tiwai, linux-kernel, lgirdwood, dl-linux-imx, kernel, festevam, linux-arm-kernel SAI might have up to 4 clock sources selected by an internal CLK mux. On imx6/7 mclk0/mclk1 are the same, while on imx8 mclk0 and mclk1 are coming from different sources. Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> --- Documentation/devicetree/bindings/sound/fsl-sai.txt | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/Documentation/devicetree/bindings/sound/fsl-sai.txt b/Documentation/devicetree/bindings/sound/fsl-sai.txt index 2e726b983845..db0497d1920a 100644 --- a/Documentation/devicetree/bindings/sound/fsl-sai.txt +++ b/Documentation/devicetree/bindings/sound/fsl-sai.txt @@ -15,8 +15,9 @@ Required properties: - clocks : Must contain an entry for each entry in clock-names. - clock-names : Must include the "bus" for register access and - "mclk1", "mclk2", "mclk3" for bit clock and frame - clock providing. + "mclk0", "mclk1", "mclk2", "mclk3" the four clock + sources of the SAI clock MUX selecting a clock + for bit clock and frame clock providing. - dmas : Generic dma devicetree binding as described in Documentation/devicetree/bindings/dma/dma.txt. -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI 2019-05-28 13:21 ` [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI Daniel Baluta @ 2019-06-14 20:00 ` Rob Herring 0 siblings, 0 replies; 8+ messages in thread From: Rob Herring @ 2019-06-14 20:00 UTC (permalink / raw) To: Daniel Baluta Cc: mark.rutland, devicetree, alsa-devel, Daniel Baluta, timur, Xiubo.Lee, festevam, s.hauer, tiwai, linux-kernel, robh+dt, lgirdwood, nicoleotsuka, broonie, dl-linux-imx, kernel, shawnguo, linux-arm-kernel On Tue, 28 May 2019 13:21:01 +0000, Daniel Baluta wrote: > SAI might have up to 4 clock sources selected by an internal > CLK mux. > > On imx6/7 mclk0/mclk1 are the same, while on imx8 mclk0 and > mclk1 are coming from different sources. > > Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> > --- > Documentation/devicetree/bindings/sound/fsl-sai.txt | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > Reviewed-by: Rob Herring <robh@kernel.org> _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH 3/3] ASoC: fsl_sai: Read SAI clock source 0 from DT 2019-05-28 13:20 [PATCH 0/3] Add mclk0 clock source for SAI Daniel Baluta 2019-05-28 13:21 ` [PATCH 1/3] ARM: dts: imx: Add mclk0 clock " Daniel Baluta 2019-05-28 13:21 ` [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI Daniel Baluta @ 2019-05-28 13:21 ` Daniel Baluta 2019-05-29 23:03 ` [PATCH 0/3] Add mclk0 clock source for SAI Nicolin Chen 3 siblings, 0 replies; 8+ messages in thread From: Daniel Baluta @ 2019-05-28 13:21 UTC (permalink / raw) To: robh+dt, shawnguo, timur, nicoleotsuka, broonie Cc: mark.rutland, devicetree, alsa-devel, Xiubo.Lee, Daniel Baluta, s.hauer, tiwai, linux-kernel, lgirdwood, dl-linux-imx, kernel, festevam, S.j. Wang, linux-arm-kernel SAI provide multiple master clock source options selectable via bit MSEL of TCR2/RCR2. All possible master clock sources are stored in sai->mclk_clk array. Current implementation assumes that MCLK0 source is always busclk, but this is wrong! For example, on i.MX8QM we have: 00b - Bus Clock selected. 01b - Master Clock (MCLK) 1 option selected. 10b - Master Clock (MCLK) 2 option selected. 11b - Master Clock (MCLK) 3 option selected. while on i.MX6SX we have: 00b - Master Clock (MCLK) 1 option selected. 01b - Master Clock (MCLK) 1 option selected. 10b - Master Clock (MCLK) 2 option selected. 11b - Master Clock (MCLK) 3 option selected. So, this patch will read mclk0 source clock from device tree. Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com> Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com> --- sound/soc/fsl/fsl_sai.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index db9e0872f73d..b563004fb89f 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -826,8 +826,7 @@ static int fsl_sai_probe(struct platform_device *pdev) sai->bus_clk = NULL; } - sai->mclk_clk[0] = sai->bus_clk; - for (i = 1; i < FSL_SAI_MCLK_MAX; i++) { + for (i = 0; i < FSL_SAI_MCLK_MAX; i++) { sprintf(tmp, "mclk%d", i); sai->mclk_clk[i] = devm_clk_get(&pdev->dev, tmp); if (IS_ERR(sai->mclk_clk[i])) { -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH 0/3] Add mclk0 clock source for SAI 2019-05-28 13:20 [PATCH 0/3] Add mclk0 clock source for SAI Daniel Baluta ` (2 preceding siblings ...) 2019-05-28 13:21 ` [PATCH 3/3] ASoC: fsl_sai: Read SAI clock source 0 from DT Daniel Baluta @ 2019-05-29 23:03 ` Nicolin Chen 2019-05-30 8:32 ` Daniel Baluta 3 siblings, 1 reply; 8+ messages in thread From: Nicolin Chen @ 2019-05-29 23:03 UTC (permalink / raw) To: Daniel Baluta Cc: mark.rutland, devicetree, alsa-devel, timur, Xiubo.Lee, festevam, s.hauer, tiwai, linux-kernel, robh+dt, lgirdwood, broonie, dl-linux-imx, kernel, shawnguo, linux-arm-kernel On Tue, May 28, 2019 at 01:20:46PM +0000, Daniel Baluta wrote: > 1) SAI clock source select MUX is really part of the hardware > 2) flexibility! We let DT tell us which is the option for MUX > option 0. I think the "MUX" is plausible comparing to your previous version. As long as DT maintainers ack the DT binding doc, I would be okay to ack too. Just one comments at the dts/dtsi changes, I know the driver would just warn old DTs, but it does change the behavior at the mclk_clk[0] from previously bus_clk to NULL after this series. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH 0/3] Add mclk0 clock source for SAI 2019-05-29 23:03 ` [PATCH 0/3] Add mclk0 clock source for SAI Nicolin Chen @ 2019-05-30 8:32 ` Daniel Baluta 0 siblings, 0 replies; 8+ messages in thread From: Daniel Baluta @ 2019-05-30 8:32 UTC (permalink / raw) To: nicoleotsuka Cc: mark.rutland, devicetree, alsa-devel, lgirdwood, timur, Xiubo.Lee, shawnguo, broonie, linux-kernel, tiwai, robh+dt, dl-linux-imx, kernel, festevam, s.hauer, linux-arm-kernel On Wed, 2019-05-29 at 16:03 -0700, Nicolin Chen wrote: > On Tue, May 28, 2019 at 01:20:46PM +0000, Daniel Baluta wrote: > > > 1) SAI clock source select MUX is really part of the hardware > > 2) flexibility! We let DT tell us which is the option for MUX > > option 0. > > I think the "MUX" is plausible comparing to your previous version. > As long as DT maintainers ack the DT binding doc, I would be okay > to ack too. Just one comments at the dts/dtsi changes, I know the > driver would just warn old DTs, but it does change the behavior at > the mclk_clk[0] from previously bus_clk to NULL after this series. Thanks for review, will fix in v2. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2019-06-14 20:01 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2019-05-28 13:20 [PATCH 0/3] Add mclk0 clock source for SAI Daniel Baluta 2019-05-28 13:21 ` [PATCH 1/3] ARM: dts: imx: Add mclk0 clock " Daniel Baluta 2019-05-29 22:57 ` Nicolin Chen 2019-05-28 13:21 ` [PATCH 2/3] dt-bindings: sound: Clarify the usage of clocks in SAI Daniel Baluta 2019-06-14 20:00 ` Rob Herring 2019-05-28 13:21 ` [PATCH 3/3] ASoC: fsl_sai: Read SAI clock source 0 from DT Daniel Baluta 2019-05-29 23:03 ` [PATCH 0/3] Add mclk0 clock source for SAI Nicolin Chen 2019-05-30 8:32 ` Daniel Baluta
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