[PATCH v2 08/11] sound: line6: move to use usb_control_msg_send() and usb_control_msg_recv()

Greg Kroah-Hartman
2020-09-07T15:50:20Z

The usb_control_msg_send() and usb_control_msg_recv() calls can return
an error if a "short" write/read happens, and they can handle data off
of the stack, so move the driver over to using those calls instead,
saving some logic when dynamically allocating memory.

Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Vasily Khoruzhick <anarsoul@gmail.com>
Cc: alsa-devel@alsa-project.org
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
v2:
- Added reviewed-by from Takashi

sound/usb/line6/driver.c | 69 +++++++++++++++-----------------------
sound/usb/line6/podhd.c | 17 ++++------
sound/usb/line6/toneport.c | 8 ++---
3 files changed, 37 insertions(+), 57 deletions(-)

diff --git a/sound/usb/line6/driver.c b/sound/usb/line6/driver.c
index 60674ce4879b..601292c51491 100644
--- a/sound/usb/line6/driver.c
+++ b/sound/usb/line6/driver.c
@@ -337,23 +337,18 @@ int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
{
struct usb_device *usbdev = line6->usbdev;
int ret;
- unsigned char *len;
+ u8 len;
unsigned count;

if (address > 0xffff || datalen > 0xff)
return -EINVAL;

- len = kmalloc(1, GFP_KERNEL);
- if (!len)
- return -ENOMEM;
-
/* query the serial number: */
- ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
- (datalen << 8) | 0x21, address,
- NULL, 0, LINE6_TIMEOUT * HZ);
-
- if (ret < 0) {
+ ret = usb_control_msg_send(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+ (datalen << 8) | 0x21, address, NULL, 0,
+ LINE6_TIMEOUT * HZ);
+ if (ret) {
dev_err(line6->ifcdev, "read request failed (error %d)\n", ret);
goto exit;
}
@@ -362,45 +357,41 @@ int line6_read_data(struct usb_line6 *line6, unsigned address, void *data,
for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
mdelay(LINE6_READ_WRITE_STATUS_DELAY);

- ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE |
- USB_DIR_IN,
- 0x0012, 0x0000, len, 1,
- LINE6_TIMEOUT * HZ);
- if (ret < 0) {
+ ret = usb_control_msg_recv(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ 0x0012, 0x0000, &len, 1,
+ LINE6_TIMEOUT * HZ);
+ if (ret) {
dev_err(line6->ifcdev,
"receive length failed (error %d)\n", ret);
goto exit;
}

- if (*len != 0xff)
+ if (len != 0xff)
break;
}

ret = -EIO;
- if (*len == 0xff) {
+ if (len == 0xff) {
dev_err(line6->ifcdev, "read failed after %d retries\n",
count);
goto exit;
- } else if (*len != datalen) {
+ } else if (len != datalen) {
/* should be equal or something went wrong */
dev_err(line6->ifcdev,
"length mismatch (expected %d, got %d)\n",
- (int)datalen, (int)*len);
+ (int)datalen, len);
goto exit;
}

/* receive the result: */
- ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
- 0x0013, 0x0000, data, datalen,
- LINE6_TIMEOUT * HZ);
-
- if (ret < 0)
+ ret = usb_control_msg_recv(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ 0x0013, 0x0000, data, datalen, LINE6_TIMEOUT * HZ);
+ if (ret)
dev_err(line6->ifcdev, "read failed (error %d)\n", ret);

exit:
- kfree(len);
return ret;
}
EXPORT_SYMBOL_GPL(line6_read_data);
@@ -423,12 +414,10 @@ int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
if (!status)
return -ENOMEM;

- ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
- 0x0022, address, data, datalen,
- LINE6_TIMEOUT * HZ);
-
- if (ret < 0) {
+ ret = usb_control_msg_send(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+ 0x0022, address, data, datalen, LINE6_TIMEOUT * HZ);
+ if (ret) {
dev_err(line6->ifcdev,
"write request failed (error %d)\n", ret);
goto exit;
@@ -437,14 +426,10 @@ int line6_write_data(struct usb_line6 *line6, unsigned address, void *data,
for (count = 0; count < LINE6_READ_WRITE_MAX_RETRIES; count++) {
mdelay(LINE6_READ_WRITE_STATUS_DELAY);

- ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0),
- 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE |
- USB_DIR_IN,
- 0x0012, 0x0000,
- status, 1, LINE6_TIMEOUT * HZ);
-
- if (ret < 0) {
+ ret = usb_control_msg_recv(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
+ 0x0012, 0x0000, status, 1, LINE6_TIMEOUT * HZ);
+ if (ret) {
dev_err(line6->ifcdev,
"receiving status failed (error %d)\n", ret);
goto exit;
diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c
index eef45f7fef0d..a1261f55d62b 100644
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -183,29 +183,25 @@ static const struct attribute_group podhd_dev_attr_group = {
static int podhd_dev_start(struct usb_line6_podhd *pod)
{
int ret;
- u8 *init_bytes;
+ u8 init_bytes[8];
int i;
struct usb_device *usbdev = pod->line6.usbdev;

- init_bytes = kmalloc(8, GFP_KERNEL);
- if (!init_bytes)
- return -ENOMEM;
-
- ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0),
+ ret = usb_control_msg_send(usbdev, 0,
0x67, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
0x11, 0,
NULL, 0, LINE6_TIMEOUT * HZ);
- if (ret < 0) {
+ if (ret) {
dev_err(pod->line6.ifcdev, "read request failed (error %d)\n", ret);
goto exit;
}

/* NOTE: looks like some kind of ping message */
- ret = usb_control_msg(usbdev, usb_rcvctrlpipe(usbdev, 0), 0x67,
+ ret = usb_control_msg_recv(usbdev, 0, 0x67,
USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
0x11, 0x0,
init_bytes, 3, LINE6_TIMEOUT * HZ);
- if (ret < 0) {
+ if (ret) {
dev_err(pod->line6.ifcdev,
"receive length failed (error %d)\n", ret);
goto exit;
@@ -220,13 +216,12 @@ static int podhd_dev_start(struct usb_line6_podhd *pod)
goto exit;
}

- ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0),
+ ret = usb_control_msg_send(usbdev, 0,
USB_REQ_SET_FEATURE,
USB_TYPE_STANDARD | USB_RECIP_DEVICE | USB_DIR_OUT,
1, 0,
NULL, 0, LINE6_TIMEOUT * HZ);
exit:
- kfree(init_bytes);
return ret;
}

diff --git a/sound/usb/line6/toneport.c b/sound/usb/line6/toneport.c
index 94dd5e7ab2e6..a9b56085b76a 100644
--- a/sound/usb/line6/toneport.c
+++ b/sound/usb/line6/toneport.c
@@ -126,11 +126,11 @@ static int toneport_send_cmd(struct usb_device *usbdev, int cmd1, int cmd2)
{
int ret;

- ret = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x67,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
- cmd1, cmd2, NULL, 0, LINE6_TIMEOUT * HZ);
+ ret = usb_control_msg_send(usbdev, 0, 0x67,
+ USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
+ cmd1, cmd2, NULL, 0, LINE6_TIMEOUT * HZ);

- if (ret < 0) {
+ if (ret) {
dev_err(&usbdev->dev, "send failed (error %d)\n", ret);
return ret;
}
--
2.28.0