Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Takashi Iwai <tiwai@suse.de>
To:     alsa-devel@alsa-project.org
Cc:     linux-kernel@vger.kernel.org, Takashi Iwai <tiwai@suse.de>
Subject: [PATCH 07/25] ALSA: es1938: Convert to generic PCM copy ops
Date:   Mon, 14 Aug 2023 13:55:05 +0200
Message-Id: <20230814115523.15279-8-tiwai@suse.de>
In-Reply-To: <20230814115523.15279-1-tiwai@suse.de>
References: <20230814115523.15279-1-tiwai@suse.de>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

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 inverted from copy_from/to_user().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
 sound/pci/es1938.c | 30 +++++-------------------------
 1 file changed, 5 insertions(+), 25 deletions(-)

diff --git a/sound/pci/es1938.c b/sound/pci/es1938.c
index e34ec6f89e7e..9e28e9fecd2a 100644
--- 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))
 			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))
 			return -EFAULT;
-		if (put_user(runtime->dma_area[0],
-			     ((unsigned char __user *)dst) + count - 1))
+		if (!copy_to_iter(runtime->dma_area, 1, dst))
 			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)
-- 
2.35.3