On Mon, Oct 18, 2021 at 12:48:44PM +0100, John Keeping wrote:
> This effectively reverts commit 75b31192fe6a ("ASoC: rockchip: add
> config for rockchip dmaengine pcm register").

> There doesn't seem to be any rationale given for why these specific
> values are helpful.  The generic DMA engine provides sensible defaults
> here and works well with Rockchip I2S.

> In fact the period size here is really quite restrictive when dealing
> with 8 channels of 32-bit data as the effective period size is just 256
> frames.

Copying in Jianqun who wrote that patch.  If you're reverting a patch
it's generally good to make sure the original author is aware,
particularly if you're unsure as to why the patch does what it does.

> Signed-off-by: John Keeping <john@metanate.com>
> ---
>  sound/soc/rockchip/Makefile       |  3 +--
>  sound/soc/rockchip/rockchip_i2s.c |  3 +--
>  sound/soc/rockchip/rockchip_pcm.c | 44 -------------------------------
>  sound/soc/rockchip/rockchip_pcm.h | 11 --------
>  4 files changed, 2 insertions(+), 59 deletions(-)
>  delete mode 100644 sound/soc/rockchip/rockchip_pcm.c
>  delete mode 100644 sound/soc/rockchip/rockchip_pcm.h
> 
> diff --git a/sound/soc/rockchip/Makefile b/sound/soc/rockchip/Makefile
> index b10f5e7b136d..6a3e61178152 100644
> --- a/sound/soc/rockchip/Makefile
> +++ b/sound/soc/rockchip/Makefile
> @@ -2,11 +2,10 @@
>  # ROCKCHIP Platform Support
>  snd-soc-rockchip-i2s-objs := rockchip_i2s.o
>  snd-soc-rockchip-i2s-tdm-objs := rockchip_i2s_tdm.o
> -snd-soc-rockchip-pcm-objs := rockchip_pcm.o
>  snd-soc-rockchip-pdm-objs := rockchip_pdm.o
>  snd-soc-rockchip-spdif-objs := rockchip_spdif.o
>  
> -obj-$(CONFIG_SND_SOC_ROCKCHIP_I2S) += snd-soc-rockchip-i2s.o snd-soc-rockchip-pcm.o
> +obj-$(CONFIG_SND_SOC_ROCKCHIP_I2S) += snd-soc-rockchip-i2s.o
>  obj-$(CONFIG_SND_SOC_ROCKCHIP_I2S_TDM) += snd-soc-rockchip-i2s-tdm.o
>  obj-$(CONFIG_SND_SOC_ROCKCHIP_PDM) += snd-soc-rockchip-pdm.o
>  obj-$(CONFIG_SND_SOC_ROCKCHIP_SPDIF) += snd-soc-rockchip-spdif.o
> diff --git a/sound/soc/rockchip/rockchip_i2s.c b/sound/soc/rockchip/rockchip_i2s.c
> index 7e89f5b0c237..a6d7656c206e 100644
> --- a/sound/soc/rockchip/rockchip_i2s.c
> +++ b/sound/soc/rockchip/rockchip_i2s.c
> @@ -20,7 +20,6 @@
>  #include <sound/dmaengine_pcm.h>
>  
>  #include "rockchip_i2s.h"
> -#include "rockchip_pcm.h"
>  
>  #define DRV_NAME "rockchip-i2s"
>  
> @@ -756,7 +755,7 @@ static int rockchip_i2s_probe(struct platform_device *pdev)
>  		goto err_suspend;
>  	}
>  
> -	ret = rockchip_pcm_platform_register(&pdev->dev);
> +	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
>  	if (ret) {
>  		dev_err(&pdev->dev, "Could not register PCM\n");
>  		goto err_suspend;
> diff --git a/sound/soc/rockchip/rockchip_pcm.c b/sound/soc/rockchip/rockchip_pcm.c
> deleted file mode 100644
> index 02254e42135e..000000000000
> --- a/sound/soc/rockchip/rockchip_pcm.c
> +++ /dev/null
> @@ -1,44 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0-only
> -/*
> - * Copyright (c) 2018 Rockchip Electronics Co. Ltd.
> - */
> -
> -#include <linux/device.h>
> -#include <linux/init.h>
> -#include <linux/module.h>
> -
> -#include <sound/core.h>
> -#include <sound/pcm.h>
> -#include <sound/soc.h>
> -#include <sound/dmaengine_pcm.h>
> -
> -#include "rockchip_pcm.h"
> -
> -static const struct snd_pcm_hardware snd_rockchip_hardware = {
> -	.info			= SNDRV_PCM_INFO_MMAP |
> -				  SNDRV_PCM_INFO_MMAP_VALID |
> -				  SNDRV_PCM_INFO_PAUSE |
> -				  SNDRV_PCM_INFO_RESUME |
> -				  SNDRV_PCM_INFO_INTERLEAVED,
> -	.period_bytes_min	= 32,
> -	.period_bytes_max	= 8192,
> -	.periods_min		= 1,
> -	.periods_max		= 52,
> -	.buffer_bytes_max	= 64 * 1024,
> -	.fifo_size		= 32,
> -};
> -
> -static const struct snd_dmaengine_pcm_config rk_dmaengine_pcm_config = {
> -	.pcm_hardware = &snd_rockchip_hardware,
> -	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
> -	.prealloc_buffer_size = 32 * 1024,
> -};
> -
> -int rockchip_pcm_platform_register(struct device *dev)
> -{
> -	return devm_snd_dmaengine_pcm_register(dev, &rk_dmaengine_pcm_config,
> -		SND_DMAENGINE_PCM_FLAG_COMPAT);
> -}
> -EXPORT_SYMBOL_GPL(rockchip_pcm_platform_register);
> -
> -MODULE_LICENSE("GPL v2");
> diff --git a/sound/soc/rockchip/rockchip_pcm.h b/sound/soc/rockchip/rockchip_pcm.h
> deleted file mode 100644
> index 7f00e2ce3603..000000000000
> --- a/sound/soc/rockchip/rockchip_pcm.h
> +++ /dev/null
> @@ -1,11 +0,0 @@
> -/* SPDX-License-Identifier: GPL-2.0-only */
> -/*
> - * Copyright (c) 2018 Rockchip Electronics Co. Ltd.
> - */
> -
> -#ifndef _ROCKCHIP_PCM_H
> -#define _ROCKCHIP_PCM_H
> -
> -int rockchip_pcm_platform_register(struct device *dev);
> -
> -#endif
> -- 
> 2.33.1
>