ALSA: es1938: Convert to generic PCM copy ops

This patch converts the es1938 driver code to use the new unified PCM
copy callback.  It's a straightforward conversion from *_user() to
*_iter() variants in most parts.

Note that copy_from/to_iter() returns the copied bytes, hence the
error condition is adjusted accordingly.

Link: https://lore.kernel.org/r/20230815190136.8987-8-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/pci/es1938.c b/sound/pci/es1938.c
index e34ec6f..ec598ba 100644 (file)
--- a/sound/pci/es1938.c
+++ b/sound/pci/es1938.c
@@ -824,7 +824,7 @@ static snd_pcm_uframes_t snd_es1938_playback_pointer(struct snd_pcm_substream *s
 
 static int snd_es1938_capture_copy(struct snd_pcm_substream *substream,
                                   int channel, unsigned long pos,
-                                  void __user *dst, unsigned long count)
+                                  struct iov_iter *dst, unsigned long count)
 {
        struct snd_pcm_runtime *runtime = substream->runtime;
        struct es1938 *chip = snd_pcm_substream_chip(substream);
@@ -832,36 +832,17 @@ static int snd_es1938_capture_copy(struct snd_pcm_substream *substream,
        if (snd_BUG_ON(pos + count > chip->dma1_size))
                return -EINVAL;
        if (pos + count < chip->dma1_size) {
-               if (copy_to_user(dst, runtime->dma_area + pos + 1, count))
+               if (copy_to_iter(runtime->dma_area + pos + 1, count, dst) != count)
                        return -EFAULT;
        } else {
-               if (copy_to_user(dst, runtime->dma_area + pos + 1, count - 1))
+               if (copy_to_iter(runtime->dma_area + pos + 1, count - 1, dst) != count - 1)
                        return -EFAULT;
-               if (put_user(runtime->dma_area[0],
-                            ((unsigned char __user *)dst) + count - 1))
+               if (copy_to_iter(runtime->dma_area, 1, dst) != 1)
                        return -EFAULT;
        }
        return 0;
 }
 
-static int snd_es1938_capture_copy_kernel(struct snd_pcm_substream *substream,
-                                         int channel, unsigned long pos,
-                                         void *dst, unsigned long count)
-{
-       struct snd_pcm_runtime *runtime = substream->runtime;
-       struct es1938 *chip = snd_pcm_substream_chip(substream);
-
-       if (snd_BUG_ON(pos + count > chip->dma1_size))
-               return -EINVAL;
-       if (pos + count < chip->dma1_size) {
-               memcpy(dst, runtime->dma_area + pos + 1, count);
-       } else {
-               memcpy(dst, runtime->dma_area + pos + 1, count - 1);
-               runtime->dma_area[0] = *((unsigned char *)dst + count - 1);
-       }
-       return 0;
-}
-
 /* ----------------------------------------------------------------------
  * Audio1 Capture (ADC)
  * ----------------------------------------------------------------------*/
@@ -987,8 +968,7 @@ static const struct snd_pcm_ops snd_es1938_capture_ops = {
        .prepare =      snd_es1938_capture_prepare,
        .trigger =      snd_es1938_capture_trigger,
        .pointer =      snd_es1938_capture_pointer,
-       .copy_user =    snd_es1938_capture_copy,
-       .copy_kernel =  snd_es1938_capture_copy_kernel,
+       .copy =         snd_es1938_capture_copy,
 };
 
 static int snd_es1938_new_pcm(struct es1938 *chip, int device)