Re: [PATCH 19/25] ASoC: mediatek: Convert to generic PCM copy ops

On Mon, Aug 14, 2023 at 01:55:17PM +0200, Takashi Iwai wrote:

This patch converts the mediatek BT SCO driver code to use the new unified PCM copy callback. It's a straightforward conversion from *_user() to *_iter() variants. As copy_form/to_iter() updates the internal offset at each read/write, we can drop the cur_*_idx counter in the loop, too.

Note that copy_from/to_iter() returns the copied bytes, hence the error condition is inverted from copy_from/to_user().

...

• if (!copy_to_iter(bt->rx_packet_buf + cur_read_idx,
  

!= read_size ?

• 		  read_size, buf)) {
  dev_warn(bt->dev, "%s(), copy_to_user fail\n",
  

Forgot to fix the message.

		 __func__);
	return -EFAULT;

...

• if (!copy_from_iter(bt->tx_packet_buf + cur_write_idx,
  

• 		    write_size, buf)) {
  dev_warn(bt->dev, "%s(), copy_from_user fail\n",
  	 __func__);
  return -EFAULT;
  

As per above.