[PATCH] ALSA: msnd: Use proper mmap method

[PATCH] ALSA: msnd: Use proper mmap method

[Takashi Iwai]

The old ISA MSND driver basically maps the iomem as the DMA buffer.
For this type of buffer, we have already the standard mmap helper,
snd_pcm_lib_mmap_iomem().  Set the DMA address and use the standard
helper for allowing the mmap on all architectures properly.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/isa/msnd/msnd.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/sound/isa/msnd/msnd.c b/sound/isa/msnd/msnd.c
index 4fbc22a5bc5a..e23eaf449c50 100644
--- a/sound/isa/msnd/msnd.c
+++ b/sound/isa/msnd/msnd.c
@@ -473,6 +473,7 @@ static int snd_msnd_playback_open(struct snd_pcm_substream *substream)
 	snd_msnd_enable_irq(chip);
 
 	runtime->dma_area = (__force void *)chip->mappedbase;
+	runtime->dma_addr = chip->base;
 	runtime->dma_bytes = 0x3000;
 
 	chip->playback_substream = substream;
@@ -566,6 +567,7 @@ static const struct snd_pcm_ops snd_msnd_playback_ops = {
 	.prepare =	snd_msnd_playback_prepare,
 	.trigger =	snd_msnd_playback_trigger,
 	.pointer =	snd_msnd_playback_pointer,
+	.mmap =		snd_pcm_lib_mmap_iomem,
 };
 
 static int snd_msnd_capture_open(struct snd_pcm_substream *substream)
@@ -576,6 +578,7 @@ static int snd_msnd_capture_open(struct snd_pcm_substream *substream)
 	set_bit(F_AUDIO_READ_INUSE, &chip->flags);
 	snd_msnd_enable_irq(chip);
 	runtime->dma_area = (__force void *)chip->mappedbase + 0x3000;
+	runtime->dma_addr = chip->base + 0x3000;
 	runtime->dma_bytes = 0x3000;
 	memset(runtime->dma_area, 0, runtime->dma_bytes);
 	chip->capture_substream = substream;
@@ -662,6 +665,7 @@ static const struct snd_pcm_ops snd_msnd_capture_ops = {
 	.prepare =	snd_msnd_capture_prepare,
 	.trigger =	snd_msnd_capture_trigger,
 	.pointer =	snd_msnd_capture_pointer,
+	.mmap =		snd_pcm_lib_mmap_iomem,
 };
 
 
-- 
2.26.2

Re: [PATCH] ALSA: msnd: Use proper mmap method

[Takashi Iwai]

On Mon, 09 Aug 2021 15:59:26 +0200,
Takashi Iwai wrote:
> 
> The old ISA MSND driver basically maps the iomem as the DMA buffer.
> For this type of buffer, we have already the standard mmap helper,
> snd_pcm_lib_mmap_iomem().  Set the DMA address and use the standard
> helper for allowing the mmap on all architectures properly.

We need to set the different PCM INFO flag for this.
Will resubmit v2 patch covering that, too.


Takashi