From: Kenneth Westfield kwestfie@codeaurora.org
This patch series adds support for I2S audio playback on the Storm board, which contains a Qualcomm Technologies ipq806x SOC and a Maxim max98357a DAC/amp.
The ipq806x SOC has audio-related hardware blocks in its low-power audio subsystem (or LPASS). One of the relevant blocks in the LPASS is its low-power audio interface (or LPAIF). This contains an MI2S port, which is what these drivers are configured to use. The LPAIF also contains a DMA engine that is dedicated to moving audio samples into the transmit FIFO of the MI2S port.
One bus from the MI2S port of the SOC is connected to the DAC/amp for stereo playback. This bus is configured so that the SOC is bus master and consists of DATA, LRCLK, and BCLK. The DAC/amp does not need MCLK to operate. In addition, a single GPIO pin from the SOC is connected to the same DAC/amp, which gives enable/disable control over the DAC/amp.
The specific drivers added are: * a codec DAI driver for controlling the DAC/amp (applied from V4) * a CPU DAI driver for controlling the MI2S port (applied from V7) * a platform driver for controlling the LPAIF DMA engine (applied from V7) * a machine driver that instantiates a dai-link for playback
The LPASS also contains clocks that need to be controlled. Those drivers have been submitted as several separate patch series: * [PATCH v3 0/8] qcom audio clock control drivers http://lkml.org/lkml/2015/1/19/656 * [PATCH] arm: dts: qcom: Add LCC nodes https://lkml.org/lkml/2015/1/28/557 * [PATCH 1/2] arm: qcom_defconfig: Enable lpass clock driver https://lkml.org/lkml/2015/1/28/582 * [PATCH] clk: qcom: Fix ipq806x LCC frequency tables https://lkml.org/lkml/2015/2/26/774 * [PATCH v2] clk: qcom: Properly change rates for ahbix clock https://lkml.org/lkml/2015/3/6/878
Even though the ipq806x LPASS does not contain an audio DSP, other SOCs do have one. For those SOCs, the audio DSP typically controls the hardware blocks in the LPASS. Hence, different CPU DAI driver(s) would need to be used in order to facilitate audio with the DSP. As such, the LPASS DT binding description alludes to an optional adsp phandle, which is not present for this SOC. For other SOCs that do contain an audio DSP, the phandle should exist and refer to a an adsp node. Not using the audio DSP on an SOC that does have one would require different CPU DAI driver(s), in addition to possible bootloader and/or firmware changes.
Note that the use of a phandle was a modification that has been submitted as part of a separate patch series.
Corresponding additions to the device tree for the ipq806x SOC and its documentation have also been added. Also, as this is a new directory, the MAINTAINERS file has been updated as well (applied from V7).
= Changes since V7 [Patch V7 00/10] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2015-March/088546.html
* Changed the compatible property of the machine driver to make it specific to audio * Removed the lcc node definition from the DT, as it was submitted separately
= Changes since V6 [Patch V6 00/10] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2015-February/088218.ht...
* Added REGMAP_MMIO selection for the CPU and platform drivers * Modified the AHBIX frequency to match the corresponding LCC fix * Tweaked the logging in the CPU driver probe.
= Changes since V5 [Patch V5 00/12] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2015-February/087832.ht...
* Correctly use Storm as the build target label and DT binding label. * Added audio DSP sub-node to the LPASS device tree, disabled for this SOC. * Added logic to CPU DAI driver to fail the probe() if a DSP is present. * Use the standard naming convention for the DAI link properties. * General code cleanup.
= Changes since V4 [Patch V4 00/10] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2015-February/087499.ht...
* Replaced simple-card with a machine driver to resolve the system clock configuration, rather than having the CPU DAI driver do it. * Added header files to avoid indirect header dependencies and implicit forward declarations. * Tweaked the ISR to match the conventions of the surrounding code. * Removed the usage of the low-power memory as it is not needed. * Removed the use of the DRV_NAME constant. * Added explicit dependency on gpiolib for the codec driver. * Moved the MODULE_DEVICE_TABLE macro inside the CONFIG_OF conditional. * Modified the documentation to reflect the changes. * General code cleanup.
= Changes since V3 [Patch V3 00/10] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2014-December/085694.ht...
* Placed the content of the inline functions into the callbacks. * Replaced use of readl/writel register access functions with regmap access functions. Notable exception is the ISR, which uses ioread32/iowrite32. * Rearranged the sequencing of the hardware block enables to fit within the ASoC framework callbacks, while remaining functional. REQ 1: The hardware requires the enable sequence to be: LPAIF-DMA[enable],then LPAIF-MI2S[enable], then DAC-GPIO[enable] REQ 2: The hardware requires the disable sequence to be: DAC-GPIO[disable], then LPAIF-MI2S[disable] * Corrected the implementation of the pointer callback. * Utilize the LPM to buffer audio samples, rather than memory external to LPASS. * Corrected the interrupt clearing in the ISR. * Implemented a default system clock (defined by the simple-card DT node), and optional LPASS DT node modifiers that can alter the system clock in order to expand the range of available bit clock frequencies. * Addressed all of the remaining issues raised by Mark Brown. * General code cleanup.
= Changes since V2 [Patch v2 00/11] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2014-December/085186.ht...
* Removed the PCM platform driver from the DTS platform and tied it to the CPU DAI driver. * Changed I2S pinctrl to use generic naming convention and moved control to CPU DAI driver. It should be controlled now by soc-core's pinctrl_pm_* functionality. * Added stub DAPM support in codec driver. As the DAC GPIO needs to be enabled last when starting playback, and disabled first when stopping playback, it seems as though the trigger function may be the place for this. Suggestions are welcome for a better place to put this. * Removed machine driver and tied DAI drivers to simple-audio-card. * Packaged the build files and Maxim codec files together in one change. * Removed QCOM as vendor from Maxim code and documentation. * Separated the SOC and board definitions into the correct DTS files. * Update device tree documentation to reflect changes. * General code cleanup.
= Changes since V1 [PATCH 0/9] ASoC: QCOM: Add support for ipq806x SOC http://mailman.alsa-project.org/pipermail/alsa-devel/2014-November/084322.ht...
* Remove the native LPAIF driver, and move its functionality to the CPU DAI driver. * Add a codec driver to manage the pins going to the external DAC (previously managed by the machine driver). * Use devm_* and dev_* where possible. * ISR only handles relevant DMA channel now. * Update device tree documentation to reflect changes. * General code cleanup.
Kenneth Westfield (5): ASoC: qcom: Document Storm bindings ASoC: qcom: Add Storm machine driver ASoC: qcom: Add ability to build QCOM drivers ASoC: Allow for building QCOM drivers ARM: dts: Model IPQ LPASS audio hardware
Documentation/devicetree/bindings/sound/storm.txt | 23 +++ arch/arm/boot/dts/qcom-ipq8064.dtsi | 16 +++ sound/soc/Kconfig | 1 + sound/soc/Makefile | 1 + sound/soc/qcom/Kconfig | 25 ++++ sound/soc/qcom/Makefile | 11 ++ sound/soc/qcom/storm.c | 162 ++++++++++++++++++++++ 7 files changed, 239 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/storm.txt create mode 100644 sound/soc/qcom/Kconfig create mode 100644 sound/soc/qcom/Makefile create mode 100644 sound/soc/qcom/storm.c