at91: kernel v5.15: copy config and patches from 5.10

[openwrt/openwrt.git] / target / linux / at91 / patches-5.15 / 144-ASoC-atmel-pdc-Use-managed-DMA-buffer-allocation.patch

diff --git a/target/linux/at91/patches-5.15/144-ASoC-atmel-pdc-Use-managed-DMA-buffer-allocation.patch b/target/linux/at91/patches-5.15/144-ASoC-atmel-pdc-Use-managed-DMA-buffer-allocation.patch
new file mode 100644 (file)
index 0000000..072e13b
--- /dev/null
+++ b/target/linux/at91/patches-5.15/144-ASoC-atmel-pdc-Use-managed-DMA-buffer-allocation.patch
@@ -0,0 +1,135 @@
+From 0b20c174a17dcfa805ddac1301a5af7298877ec3 Mon Sep 17 00:00:00 2001
+From: Lars-Peter Clausen <lars@metafoo.de>
+Date: Wed, 6 Jan 2021 14:36:48 +0100
+Subject: [PATCH 144/247] ASoC: atmel-pdc: Use managed DMA buffer allocation
+
+Instead of manually managing its DMA buffers using
+dma_{alloc,free}_coherent() lets the sound core take care of this using
+managed buffers.
+
+On one hand this reduces the amount of boiler plate code, but the main
+motivation for the change is to use the shared code where possible. This
+makes it easier to argue about correctness and that the code does not
+contain subtle bugs like data leakage or similar.
+
+Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
+Reviewed-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
+Link: https://lore.kernel.org/r/20210106133650.13509-1-lars@metafoo.de
+Signed-off-by: Mark Brown <broonie@kernel.org>
+---
+ sound/soc/atmel/atmel-pcm-pdc.c | 78 ++-------------------------------
+ 1 file changed, 4 insertions(+), 74 deletions(-)
+
+--- a/sound/soc/atmel/atmel-pcm-pdc.c
++++ b/sound/soc/atmel/atmel-pcm-pdc.c
+@@ -34,86 +34,21 @@
+ #include "atmel-pcm.h"
+ 
+ 
+-static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
+-      int stream)
+-{
+-      struct snd_pcm_substream *substream = pcm->streams[stream].substream;
+-      struct snd_dma_buffer *buf = &substream->dma_buffer;
+-      size_t size = ATMEL_SSC_DMABUF_SIZE;
+-
+-      buf->dev.type = SNDRV_DMA_TYPE_DEV;
+-      buf->dev.dev = pcm->card->dev;
+-      buf->private_data = NULL;
+-      buf->area = dma_alloc_coherent(pcm->card->dev, size,
+-                      &buf->addr, GFP_KERNEL);
+-      pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n",
+-                      (void *)buf->area, (void *)(long)buf->addr, size);
+-
+-      if (!buf->area)
+-              return -ENOMEM;
+-
+-      buf->bytes = size;
+-      return 0;
+-}
+-
+-static int atmel_pcm_mmap(struct snd_soc_component *component,
+-                        struct snd_pcm_substream *substream,
+-                        struct vm_area_struct *vma)
+-{
+-      return remap_pfn_range(vma, vma->vm_start,
+-                     substream->dma_buffer.addr >> PAGE_SHIFT,
+-                     vma->vm_end - vma->vm_start, vma->vm_page_prot);
+-}
+-
+ static int atmel_pcm_new(struct snd_soc_component *component,
+                        struct snd_soc_pcm_runtime *rtd)
+ {
+       struct snd_card *card = rtd->card->snd_card;
+-      struct snd_pcm *pcm = rtd->pcm;
+       int ret;
+ 
+       ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
+       if (ret)
+               return ret;
+ 
+-      if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
+-              pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n");
+-              ret = atmel_pcm_preallocate_dma_buffer(pcm,
+-                      SNDRV_PCM_STREAM_PLAYBACK);
+-              if (ret)
+-                      goto out;
+-      }
++      snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
++                                     card->dev, ATMEL_SSC_DMABUF_SIZE,
++                                     ATMEL_SSC_DMABUF_SIZE);
+ 
+-      if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
+-              pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n");
+-              ret = atmel_pcm_preallocate_dma_buffer(pcm,
+-                      SNDRV_PCM_STREAM_CAPTURE);
+-              if (ret)
+-                      goto out;
+-      }
+- out:
+-      return ret;
+-}
+-
+-static void atmel_pcm_free(struct snd_soc_component *component,
+-                         struct snd_pcm *pcm)
+-{
+-      struct snd_pcm_substream *substream;
+-      struct snd_dma_buffer *buf;
+-      int stream;
+-
+-      for (stream = 0; stream < 2; stream++) {
+-              substream = pcm->streams[stream].substream;
+-              if (!substream)
+-                      continue;
+-
+-              buf = &substream->dma_buffer;
+-              if (!buf->area)
+-                      continue;
+-              dma_free_coherent(pcm->card->dev, buf->bytes,
+-                                buf->area, buf->addr);
+-              buf->area = NULL;
+-      }
++      return 0;
+ }
+ 
+ /*--------------------------------------------------------------------------*\
+@@ -210,9 +145,6 @@ static int atmel_pcm_hw_params(struct sn
+       /* this may get called several times by oss emulation
+        * with different params */
+ 
+-      snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+-      runtime->dma_bytes = params_buffer_bytes(params);
+-
+       prtd->params = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+       prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
+ 
+@@ -384,9 +316,7 @@ static const struct snd_soc_component_dr
+       .prepare        = atmel_pcm_prepare,
+       .trigger        = atmel_pcm_trigger,
+       .pointer        = atmel_pcm_pointer,
+-      .mmap           = atmel_pcm_mmap,
+       .pcm_construct  = atmel_pcm_new,
+-      .pcm_destruct   = atmel_pcm_free,
+ };
+ 
+ int atmel_pcm_pdc_platform_register(struct device *dev)