[PATCH 06/10] sound: usx2y: move to use usb_control_msg_send()

From: Greg Kroah-Hartman
Date: Wed Sep 02 2020 - 07:03:08 EST


The usb_control_msg_send() call can handle data on the stack, as well as
returning an error if a "short" write happens, so move the driver over
to using that call instead. This ends up removing a helper function
that is no longer needed.

Cc: Jaroslav Kysela <perex@xxxxxxxx>
Cc: Takashi Iwai <tiwai@xxxxxxxx>
Cc: alsa-devel@xxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
sound/usb/usx2y/us122l.c | 42 ++++++++--------------------------------
1 file changed, 8 insertions(+), 34 deletions(-)

diff --git a/sound/usb/usx2y/us122l.c b/sound/usb/usx2y/us122l.c
index f86f7a61fb36..e5c5a0d03d8a 100644
--- a/sound/usb/usx2y/us122l.c
+++ b/sound/usb/usx2y/us122l.c
@@ -82,40 +82,13 @@ static int us144_create_usbmidi(struct snd_card *card)
&US122L(card)->midi_list, &quirk);
}

-/*
- * Wrapper for usb_control_msg().
- * Allocates a temp buffer to prevent dmaing from/to the stack.
- */
-static int us122l_ctl_msg(struct usb_device *dev, unsigned int pipe,
- __u8 request, __u8 requesttype,
- __u16 value, __u16 index, void *data,
- __u16 size, int timeout)
-{
- int err;
- void *buf = NULL;
-
- if (size > 0) {
- buf = kmemdup(data, size, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
- }
- err = usb_control_msg(dev, pipe, request, requesttype,
- value, index, buf, size, timeout);
- if (size > 0) {
- memcpy(data, buf, size);
- kfree(buf);
- }
- return err;
-}
-
static void pt_info_set(struct usb_device *dev, u8 v)
{
int ret;

- ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
- 'I',
- USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
- v, 0, NULL, 0, 1000);
+ ret = usb_control_msg_send(dev, 0, 'I',
+ USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ v, 0, NULL, 0, 1000);
snd_printdd(KERN_DEBUG "%i\n", ret);
}

@@ -305,10 +278,11 @@ static int us122l_set_sample_rate(struct usb_device *dev, int rate)
data[0] = rate;
data[1] = rate >> 8;
data[2] = rate >> 16;
- err = us122l_ctl_msg(dev, usb_sndctrlpipe(dev, 0), UAC_SET_CUR,
- USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
- UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, data, 3, 1000);
- if (err < 0)
+ err = usb_control_msg_send(dev, 0, UAC_SET_CUR,
+ USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
+ UAC_EP_CS_ATTR_SAMPLE_RATE << 8, ep, data, 3,
+ 1000);
+ if (err)
snd_printk(KERN_ERR "%d: cannot set freq %d to ep 0x%x\n",
dev->devnum, rate, ep);
return err;
--
2.28.0