The AHCLKX clock output of the McASP can be used as audio MCLK, even if the McASP runs in slave mode. Add a DT binding to make this option available in a simple-card setup. Signed-off-by: Stefan Müller-Klieser <s.mueller-klieser@xxxxxxxxx> --- Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt | 4 ++++ include/linux/platform_data/davinci_asp.h | 5 +++++ sound/soc/davinci/davinci-mcasp.c | 8 ++++++++ 3 files changed, 17 insertions(+) diff --git a/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt b/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt index 46bc982..96d6244 100644 --- a/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt +++ b/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt @@ -39,6 +39,10 @@ Optional properties: please refer to pinctrl-bindings.txt - fck_parent : Should contain a valid clock name which will be used as parent for the McASP fck +- ahclkx-en: In case the MCASP runs in slave mode, e.g. i2s SCK and WS slave, + we can still provide the MCLK to a codec PLL using the AHCLKX + transmit clock output. This setup can be activated by using this + property. Clock master mode remains unaffected. Example: diff --git a/include/linux/platform_data/davinci_asp.h b/include/linux/platform_data/davinci_asp.h index 85ad68f..c878836 100644 --- a/include/linux/platform_data/davinci_asp.h +++ b/include/linux/platform_data/davinci_asp.h @@ -44,6 +44,11 @@ struct davinci_mcasp_pdata { int clk_input_pin; /* + * Activate AHCLKX clock output in slave mode. + */ + bool ahclkx_en; + + /* * This flag works when both clock and FS are outputs for the cpu * and makes clock more accurate (FS is not symmetrical and the * clock is very fast. diff --git a/sound/soc/davinci/davinci-mcasp.c b/sound/soc/davinci/davinci-mcasp.c index 237dc67..aba888e 100644 --- a/sound/soc/davinci/davinci-mcasp.c +++ b/sound/soc/davinci/davinci-mcasp.c @@ -94,6 +94,7 @@ struct davinci_mcasp { int sysclk_freq; bool bclk_master; + bool ahclkx_en; /* McASP FIFO related */ u8 txnumevt; @@ -605,6 +606,10 @@ static int davinci_mcasp_set_sysclk(struct snd_soc_dai *dai, int clk_id, mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG, AHCLKXE); mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKRCTL_REG, AHCLKRE); mcasp_set_bits(mcasp, DAVINCI_MCASP_PDIR_REG, AHCLKX); + } else if (mcasp->ahclkx_en) { + mcasp_clr_bits(mcasp, DAVINCI_MCASP_AHCLKRCTL_REG, AHCLKRE); + mcasp_set_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG, AHCLKXE); + mcasp_set_bits(mcasp, DAVINCI_MCASP_PDIR_REG, AHCLKX); } else { mcasp_clr_bits(mcasp, DAVINCI_MCASP_AHCLKXCTL_REG, AHCLKXE); mcasp_clr_bits(mcasp, DAVINCI_MCASP_AHCLKRCTL_REG, AHCLKRE); @@ -1610,6 +1615,8 @@ static struct davinci_mcasp_pdata *davinci_mcasp_set_pdata_from_of( if (ret >= 0) pdata->op_mode = val; + pdata->ahclkx_en = of_property_read_bool(np, "ahclkx-en"); + ret = of_property_read_u32(np, "tdm-slots", &val); if (ret >= 0) { if (val < 2 || val > 32) { @@ -1851,6 +1858,7 @@ static int davinci_mcasp_probe(struct platform_device *pdev) mcasp->version = pdata->version; mcasp->txnumevt = pdata->txnumevt; mcasp->rxnumevt = pdata->rxnumevt; + mcasp->ahclkx_en = pdata->ahclkx_en; mcasp->dev = &pdev->dev; -- 1.9.1 _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel