From: ykk@rock-chips•com (Yang Kuankuan)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH RFC 09/11] sound/core: add IEC958 channel status helper
Date: Tue, 31 Mar 2015 04:30:39 -0400 [thread overview]
Message-ID: <551A5B2F.50203@rock-chips.com> (raw)
In-Reply-To: <E1YcfYA-0002vc-Al@rmk-PC.arm.linux.org.uk>
Hi Russell,
On 03/30/2015 03:40 PM, Russell King wrote:
> Add a helper to create the IEC958 channel status from an ALSA
> snd_pcm_runtime structure, taking account of the sample rate.
>
> Signed-off-by: Russell King <rmk+kernel@arm•linux.org.uk>
> ---
> include/sound/pcm_iec958.h | 9 ++++++
> sound/core/Kconfig | 3 ++
> sound/core/Makefile | 2 ++
> sound/core/pcm_iec958.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 84 insertions(+)
> create mode 100644 include/sound/pcm_iec958.h
> create mode 100644 sound/core/pcm_iec958.c
>
> diff --git a/include/sound/pcm_iec958.h b/include/sound/pcm_iec958.h
> new file mode 100644
> index 000000000000..0eed397aca8e
> --- /dev/null
> +++ b/include/sound/pcm_iec958.h
> @@ -0,0 +1,9 @@
> +#ifndef __SOUND_PCM_IEC958_H
> +#define __SOUND_PCM_IEC958_H
> +
> +#include <linux/types.h>
> +
> +int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs,
> + size_t len);
> +
> +#endif
> diff --git a/sound/core/Kconfig b/sound/core/Kconfig
> index b534c8a6046b..1507469425ec 100644
> --- a/sound/core/Kconfig
> +++ b/sound/core/Kconfig
> @@ -9,6 +9,9 @@ config SND_PCM
> config SND_PCM_ELD
> bool
>
> +config SND_PCM_IEC958
> + bool
> +
> config SND_DMAENGINE_PCM
> tristate
>
> diff --git a/sound/core/Makefile b/sound/core/Makefile
> index 591b49157b4d..70ea06712ec2 100644
> --- a/sound/core/Makefile
> +++ b/sound/core/Makefile
> @@ -14,10 +14,12 @@ snd-pcm-y := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \
> pcm_memory.o memalloc.o
> snd-pcm-$(CONFIG_SND_DMA_SGBUF) += sgbuf.o
> snd-pcm-$(CONFIG_SND_PCM_ELD) += pcm_drm_eld.o
> +snd-pcm-$(CONFIG_SND_PCM_IEC958) += snd-pcm-iec958.o
>
> # for trace-points
> CFLAGS_pcm_lib.o := -I$(src)
>
> +snd-pcm-iec958-objs := pcm_iec958.o
> snd-pcm-dmaengine-objs := pcm_dmaengine.o
>
> snd-rawmidi-objs := rawmidi.o
> diff --git a/sound/core/pcm_iec958.c b/sound/core/pcm_iec958.c
> new file mode 100644
> index 000000000000..e1ff88a17dde
> --- /dev/null
> +++ b/sound/core/pcm_iec958.c
> @@ -0,0 +1,70 @@
> +/*
> + * PCM DRM helpers
> + *
> + * 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; either version 2 of the License.
> + */
> +#include <linux/export.h>
> +#include <linux/types.h>
> +#include <sound/asoundef.h>
> +#include <sound/pcm.h>
> +#include <sound/pcm_iec958.h>
> +
> +/**
> + * snd_pcm_create_iec958_consumer - create consumer format IEC958 channel status
> + * @runtime: pcm runtime structure with ->rate filled in
> + * @cs: channel status buffer, at least four bytes
> + * @len: length of channel status buffer
> + *
> + * Create the consumer format channel status data in @cs of maximum size
> + * @len corresponding to the parameters of the PCM runtime @runtime.
> + *
> + * Drivers may wish to tweak the contents of the buffer after creation.
> + *
> + * Returns: length of buffer, or negative error code if something failed.
> + */
> +int snd_pcm_create_iec958_consumer(struct snd_pcm_runtime *runtime, u8 *cs,
> + size_t len)
> +{
> + unsigned int fs;
> +
> + if (len < 4)
> + return -EINVAL;
> +
> + switch (runtime->rate) {
> + case 32000:
> + fs = IEC958_AES3_CON_FS_32000;
> + break;
> + case 44100:
> + fs = IEC958_AES3_CON_FS_44100;
> + break;
> + case 48000:
> + fs = IEC958_AES3_CON_FS_48000;
> + break;
> + case 88200:
> + fs = IEC958_AES3_CON_FS_88200;
> + break;
> + case 96000:
> + fs = IEC958_AES3_CON_FS_96000;
> + break;
> + case 176400:
> + fs = IEC958_AES3_CON_FS_176400;
> + break;
> + case 192000:
> + fs = IEC958_AES3_CON_FS_192000;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + memset(cs, 0, len);
> +
> + cs[0] = IEC958_AES0_CON_NOT_COPYRIGHT | IEC958_AES0_CON_EMPHASIS_NONE;
> + cs[1] = IEC958_AES1_CON_GENERAL;
> + cs[2] = IEC958_AES2_CON_SOURCE_UNSPEC | IEC958_AES2_CON_CHANNEL_UNSPEC;
> + cs[3] = IEC958_AES3_CON_CLOCK_1000PPM | fs;
> +
Pretty good, also suitable to rockchip platform, but why not add the
"IEC958_AES2_CON_CHANNEL_MASK" & "IEC958_AES2_CON_WORDLEN" ?
Seems sample frequency & channle number & word length are the basic
message :)
Best regards.
Yakir Yang
> + return len;
> +}
> +EXPORT_SYMBOL(snd_pcm_create_iec958_consumer);
next prev parent reply other threads:[~2015-03-31 8:30 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-30 19:39 [RFC 0/11] dw_hdmi cleanups, audio preparation, helpers and ahb audio support Russell King - ARM Linux
2015-03-30 19:40 ` [PATCH RFC 01/11] drm: bridge/dw_hdmi: clean up hdmi_set_clk_regenerator() Russell King
2015-03-31 6:55 ` Yang Kuankuan
2015-03-31 10:35 ` Russell King - ARM Linux
2015-04-01 1:54 ` Yakir
2015-03-30 19:40 ` [PATCH RFC 02/11] drm: bridge/dw_hdmi: use drm_hdmi_avi_infoframe_from_display_mode() Russell King
[not found] ` <551A629C.5010306@rock-chips.com>
2015-03-31 11:57 ` Russell King - ARM Linux
2015-03-30 19:40 ` [PATCH RFC 03/11] drm: bridge/dw_hdmi: simplify hdmi_config_AVI() a little Russell King
2015-03-30 19:40 ` [PATCH RFC 04/11] drm: bridge/dw_hdmi: remove mhsyncpolarity/mvsyncpolarity/minterlaced Russell King
2015-03-30 19:40 ` [PATCH RFC 05/11] drm: bridge/dw_hdmi: introduce interface to setting sample rate Russell King
2015-03-30 19:40 ` [PATCH RFC 06/11] drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio Russell King
2015-03-31 7:45 ` Yang Kuankuan
2015-03-31 9:15 ` Philipp Zabel
2015-03-30 19:40 ` [PATCH RFC 07/11] drm/edid: add function to help find SADs Russell King
2015-04-01 11:47 ` Jani Nikula
2015-04-01 11:56 ` Russell King - ARM Linux
2015-04-02 10:52 ` [PATCH] drm/edid: add #defines for ELD versions Jani Nikula
2015-03-30 19:40 ` [PATCH RFC 08/11] sound/core: add DRM ELD helper Russell King
2015-03-31 9:12 ` Philipp Zabel
2015-03-30 19:40 ` [PATCH RFC 09/11] sound/core: add IEC958 channel status helper Russell King
2015-03-31 8:30 ` Yang Kuankuan [this message]
2015-03-31 9:13 ` Russell King - ARM Linux
2015-04-01 2:04 ` Yakir
2015-04-01 7:58 ` Russell King - ARM Linux
2015-03-31 9:10 ` Philipp Zabel
2015-03-31 9:16 ` Russell King - ARM Linux
2015-03-30 19:40 ` [PATCH RFC 10/11] drm: bridge/dw_hdmi-ahb-audio: add audio driver Russell King
2015-03-30 19:40 ` [PATCH RFC 11/11] drm: bridge/dw_hdmi-ahb-audio: parse ELD from HDMI driver Russell King
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