[alsa-devel] [PATCH V2 3/7] ALSA: add shell for Intel HDMI LPE audio driver

[Pierre-Louis Bossart]

Minor misses here as well.

On 1/6/17 7:21 PM, Jerome Anand wrote:
> On Baytrail and Cherrytrail, HDaudio may be fused out or disabled
> by the BIOS. This driver enables an alternate path to the i915
> display registers and DMA.
>
> Although there is no hardware path between i915 display and LPE/SST
> audio clusters, this HDMI capability is referred to in the documentation
> as "HDMI LPE Audio" so we keep the name for consistency. There is no
> hardware path or control dependencies with the LPE/SST DSP functionality.
>
> The hdmi-lpe-audio driver will be probed when the i915 driver creates
> a child platform device.
>
> Since this driver is neither SoC nor PCI, a new x86 folder is added
>
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
> Signed-off-by: Jerome Anand <jerome.anand at intel.com>

Change the commit title to remove 'shell', e.g. 'add BYT/CHT-T HDMI LPE 
audio driver' and mention that indirect calls will be removed later (to 
help with DP integration)


> diff --git a/sound/x86/Kconfig b/sound/x86/Kconfig
> new file mode 100644
> index 0000000..e9297d0
> --- /dev/null
> +++ b/sound/x86/Kconfig
> @@ -0,0 +1,16 @@
> +menuconfig SND_X86
> +	tristate "X86 sound devices"
> +	---help---
> +
> +	  X86 sound devices that don't fall under SoC or PCI categories
> +
> +if SND_X86
> +
> +config HDMI_LPE_AUDIO
> +	tristate "HDMI audio without HDaudio on Intel Atom platforms"
> +	depends on DRM_I915
> +	default n
> +	help
> +	 Choose this option to support HDMI LPE Audio mode
> +
> +endif	# SND_X86
> diff --git a/sound/x86/Makefile b/sound/x86/Makefile
> new file mode 100644
> index 0000000..baa6333
> --- /dev/null
> +++ b/sound/x86/Makefile
> @@ -0,0 +1,6 @@
> +ccflags-y += -Idrivers/gpu/drm/i915

from Takashi: Is it just for intel_lpe_audio.h?  Then rather put 
intel_lpe_audio.h to include/drm.
JA: OK

> +
> +snd-hdmi-lpe-audio-objs += \
> +	intel_hdmi_lpe_audio.o
> +
> +obj-$(CONFIG_HDMI_LPE_AUDIO) += snd-hdmi-lpe-audio.o
> diff --git a/sound/x86/intel_hdmi_lpe_audio.c b/sound/x86/intel_hdmi_lpe_audio.c
> new file mode 100644
> index 0000000..61347ab
> --- /dev/null
> +++ b/sound/x86/intel_hdmi_lpe_audio.c
> @@ -0,0 +1,623 @@
> +/*
> + *  intel_hdmi_lpe_audio.c - Intel HDMI LPE audio driver for Atom platforms
> + *
> + *  Copyright (C) 2016 Intel Corp
> + *  Authors:
> + *		Jerome Anand <jerome.anand at intel.com>
> + *		Aravind Siddappaji <aravindx.siddappaji at intel.com>
> + *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License as published by
> + *  the Free Software Foundation; version 2 of the License.
> + *
> + *  This program is distributed in the hope that it will be useful, but
> + *  WITHOUT ANY WARRANTY; without even the implied warranty of
> + *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + *  General Public License for more details.
> + *
> + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> + */
> +
> +#define pr_fmt(fmt)	"hdmi_lpe_audio: " fmt

 From Takashi: Better to use dev_*() variant.
JA: OK

> +static inline int hdmi_get_eld(void *eld)
> +{
> +	memcpy(eld, (void *)&hlpe_eld, sizeof(hlpe_eld));
> +
> +	{
> +		int i;
> +		uint8_t *eld_data = (uint8_t *)&hlpe_eld;
> +
> +		pr_debug("hdmi_get_eld:\n{{");
> +
> +		for (i = 0; i < sizeof(hlpe_eld); i++)
> +			pr_debug("0x%x, ", eld_data[i]);
> +
> +		pr_debug("}}\n");
> +	}
> +	return 0;

 From Takashi: There is a hexdump debug print helper, too.
JA: OK