media: em28xx: Clean up ALSA PCM API usages

With the recent change in ALSA PCM core, the whole open-coded vmalloc
buffer handling in this driver can be dropped by replacing with the
managed buffer allocation.

Also, snd_em28xx_hw_capture_free() is dropped since the check of
stream_started flag makes no sense; hw_free callback is guaranteed to
be called after the stream gets stopped.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/media/usb/em28xx/em28xx-audio.c b/drivers/media/usb/em28xx/em28xx-audio.c
index 79dfbb25714bf21d284a278b1aa67ee7562a5576..a5215fb1d36a5183e008ab2e0dfd5397b9b0713a 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-audio.c
+++ b/drivers/media/usb/em28xx/em28xx-audio.c
@@ -30,7 +30,6 @@
 #include <linux/spinlock.h>
 #include <linux/soundcard.h>
 #include <linux/slab.h>
-#include <linux/vmalloc.h>
 #include <linux/module.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -192,28 +191,6 @@ static int em28xx_init_audio_isoc(struct em28xx *dev)
        return 0;
 }
 
-static int snd_pcm_alloc_vmalloc_buffer(struct snd_pcm_substream *subs,
-                                       size_t size)
-{
-       struct em28xx *dev = snd_pcm_substream_chip(subs);
-       struct snd_pcm_runtime *runtime = subs->runtime;
-
-       dprintk("Allocating vbuffer\n");
-       if (runtime->dma_area) {
-               if (runtime->dma_bytes > size)
-                       return 0;
-
-               vfree(runtime->dma_area);
-       }
-       runtime->dma_area = vmalloc(size);
-       if (!runtime->dma_area)
-               return -ENOMEM;
-
-       runtime->dma_bytes = size;
-
-       return 0;
-}
-
 static const struct snd_pcm_hardware snd_em28xx_hw_capture = {
        .info = SNDRV_PCM_INFO_BLOCK_TRANSFER |
                SNDRV_PCM_INFO_MMAP           |
@@ -341,63 +318,12 @@ static int snd_em28xx_pcm_close(struct snd_pcm_substream *substream)
        }
 
        em28xx_audio_analog_set(dev);
-       if (substream->runtime->dma_area) {
-               dprintk("freeing\n");
-               vfree(substream->runtime->dma_area);
-               substream->runtime->dma_area = NULL;
-       }
        mutex_unlock(&dev->lock);
        kref_put(&dev->ref, em28xx_free_device);
 
        return 0;
 }
 
-static int snd_em28xx_hw_capture_params(struct snd_pcm_substream *substream,
-                                       struct snd_pcm_hw_params *hw_params)
-{
-       int ret;
-       struct em28xx *dev = snd_pcm_substream_chip(substream);
-
-       if (dev->disconnected)
-               return -ENODEV;
-
-       dprintk("Setting capture parameters\n");
-
-       ret = snd_pcm_alloc_vmalloc_buffer(substream,
-                                          params_buffer_bytes(hw_params));
-       if (ret < 0)
-               return ret;
-#if 0
-       /*
-        * TODO: set up em28xx audio chip to deliver the correct audio format,
-        * current default is 48000hz multiplexed => 96000hz mono
-        * which shouldn't matter since analogue TV only supports mono
-        */
-       unsigned int channels, rate, format;
-
-       format = params_format(hw_params);
-       rate = params_rate(hw_params);
-       channels = params_channels(hw_params);
-#endif
-
-       return 0;
-}
-
-static int snd_em28xx_hw_capture_free(struct snd_pcm_substream *substream)
-{
-       struct em28xx *dev = snd_pcm_substream_chip(substream);
-       struct em28xx_audio *adev = &dev->adev;
-
-       dprintk("Stop capture, if needed\n");
-
-       if (atomic_read(&adev->stream_started) > 0) {
-               atomic_set(&adev->stream_started, 0);
-               schedule_work(&adev->wq_trigger);
-       }
-
-       return 0;
-}
-
 static int snd_em28xx_prepare(struct snd_pcm_substream *substream)
 {
        struct em28xx *dev = snd_pcm_substream_chip(substream);
@@ -471,14 +397,6 @@ static snd_pcm_uframes_t snd_em28xx_capture_pointer(struct snd_pcm_substream
        return hwptr_done;
 }
 
-static struct page *snd_pcm_get_vmalloc_page(struct snd_pcm_substream *subs,
-                                            unsigned long offset)
-{
-       void *pageptr = subs->runtime->dma_area + offset;
-
-       return vmalloc_to_page(pageptr);
-}
-
 /*
  * AC97 volume control support
  */
@@ -709,12 +627,9 @@ static const struct snd_pcm_ops snd_em28xx_pcm_capture = {
        .open      = snd_em28xx_capture_open,
        .close     = snd_em28xx_pcm_close,
        .ioctl     = snd_pcm_lib_ioctl,
-       .hw_params = snd_em28xx_hw_capture_params,
-       .hw_free   = snd_em28xx_hw_capture_free,
        .prepare   = snd_em28xx_prepare,
        .trigger   = snd_em28xx_capture_trigger,
        .pointer   = snd_em28xx_capture_pointer,
-       .page      = snd_pcm_get_vmalloc_page,
 };
 
 static void em28xx_audio_free_urb(struct em28xx *dev)
@@ -936,6 +851,7 @@ static int em28xx_audio_init(struct em28xx *dev)
                goto card_free;
 
        snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_em28xx_pcm_capture);
+       snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_VMALLOC, NULL, 0, 0);
        pcm->info_flags = 0;
        pcm->private_data = dev;
        strscpy(pcm->name, "Empia 28xx Capture", sizeof(pcm->name));