staging: vt6656: clean function's error path in usbpipe.c

Avoid discarding called function's returned value. Store it instead in
order to act accordingly.

Update error path to return 0 on success and a negative errno value on
error.

Signed-off-by: Quentin Deslandes <quentin.deslandes@itdev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/vt6656/usbpipe.c b/drivers/staging/vt6656/usbpipe.c
index 5bbc56f..ff351a7 100644 (file)
--- a/drivers/staging/vt6656/usbpipe.c
+++ b/drivers/staging/vt6656/usbpipe.c
@@ -36,80 +36,86 @@
 int vnt_control_out(struct vnt_private *priv, u8 request, u16 value,
                    u16 index, u16 length, u8 *buffer)
 {
-       int status = 0;
+       int ret = 0;
        u8 *usb_buffer;
 
-       if (test_bit(DEVICE_FLAGS_DISCONNECTED, &priv->flags))
-               return STATUS_FAILURE;
+       if (test_bit(DEVICE_FLAGS_DISCONNECTED, &priv->flags)) {
+               ret = -EINVAL;
+               goto end;
+       }
 
        mutex_lock(&priv->usb_lock);
 
        usb_buffer = kmemdup(buffer, length, GFP_KERNEL);
        if (!usb_buffer) {
-               mutex_unlock(&priv->usb_lock);
-               return -ENOMEM;
+               ret = -ENOMEM;
+               goto end_unlock;
        }
 
-       status = usb_control_msg(priv->usb,
-                                usb_sndctrlpipe(priv->usb, 0),
-                                request, 0x40, value,
-                                index, usb_buffer, length, USB_CTL_WAIT);
+       ret = usb_control_msg(priv->usb,
+                             usb_sndctrlpipe(priv->usb, 0),
+                             request, 0x40, value,
+                             index, usb_buffer, length, USB_CTL_WAIT);
 
        kfree(usb_buffer);
 
-       mutex_unlock(&priv->usb_lock);
+       if (ret >= 0 && ret < (int)length)
+               ret = -EIO;
 
-       if (status < (int)length)
-               return STATUS_FAILURE;
-
-       return STATUS_SUCCESS;
+end_unlock:
+       mutex_unlock(&priv->usb_lock);
+end:
+       return ret;
 }
 
-void vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 data)
+int vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 data)
 {
-       vnt_control_out(priv, MESSAGE_TYPE_WRITE,
-                       reg_off, reg, sizeof(u8), &data);
+       return vnt_control_out(priv, MESSAGE_TYPE_WRITE,
+                              reg_off, reg, sizeof(u8), &data);
 }
 
 int vnt_control_in(struct vnt_private *priv, u8 request, u16 value,
                   u16 index, u16 length, u8 *buffer)
 {
-       int status;
+       int ret = 0;
        u8 *usb_buffer;
 
-       if (test_bit(DEVICE_FLAGS_DISCONNECTED, &priv->flags))
-               return STATUS_FAILURE;
+       if (test_bit(DEVICE_FLAGS_DISCONNECTED, &priv->flags)) {
+               ret = -EINVAL;
+               goto end;
+       }
 
        mutex_lock(&priv->usb_lock);
 
        usb_buffer = kmalloc(length, GFP_KERNEL);
        if (!usb_buffer) {
-               mutex_unlock(&priv->usb_lock);
-               return -ENOMEM;
+               ret = -ENOMEM;
+               goto end_unlock;
        }
 
-       status = usb_control_msg(priv->usb,
-                                usb_rcvctrlpipe(priv->usb, 0),
-                                request, 0xc0, value,
-                                index, usb_buffer, length, USB_CTL_WAIT);
+       ret = usb_control_msg(priv->usb,
+                             usb_rcvctrlpipe(priv->usb, 0),
+                             request, 0xc0, value,
+                             index, usb_buffer, length, USB_CTL_WAIT);
 
-       if (status == length)
+       if (ret == length)
                memcpy(buffer, usb_buffer, length);
 
        kfree(usb_buffer);
 
-       mutex_unlock(&priv->usb_lock);
+       if (ret >= 0 && ret < (int)length)
+               ret = -EIO;
 
-       if (status < (int)length)
-               return STATUS_FAILURE;
-
-       return STATUS_SUCCESS;
+end_unlock:
+       mutex_unlock(&priv->usb_lock);
+end:
+       return ret;
 }
 
-void vnt_control_in_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 *data)
+int vnt_control_in_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 *data)
 {
-       vnt_control_in(priv, MESSAGE_TYPE_READ,
-                      reg_off, reg, sizeof(u8), data);
+       return vnt_control_in(priv, MESSAGE_TYPE_READ,
+                             reg_off, reg, sizeof(u8), data);
 }
 
 static void vnt_start_interrupt_urb_complete(struct urb *urb)
@@ -147,10 +153,12 @@ static void vnt_start_interrupt_urb_complete(struct urb *urb)
 
 int vnt_start_interrupt_urb(struct vnt_private *priv)
 {
-       int status = STATUS_FAILURE;
+       int ret = 0;
 
-       if (priv->int_buf.in_use)
-               return STATUS_FAILURE;
+       if (priv->int_buf.in_use) {
+               ret = -EBUSY;
+               goto err;
+       }
 
        priv->int_buf.in_use = true;
 
@@ -163,13 +171,18 @@ int vnt_start_interrupt_urb(struct vnt_private *priv)
                         priv,
                         priv->int_interval);
 
-       status = usb_submit_urb(priv->interrupt_urb, GFP_ATOMIC);
-       if (status) {
-               dev_dbg(&priv->usb->dev, "Submit int URB failed %d\n", status);
-               priv->int_buf.in_use = false;
+       ret = usb_submit_urb(priv->interrupt_urb, GFP_ATOMIC);
+       if (ret) {
+               dev_dbg(&priv->usb->dev, "Submit int URB failed %d\n", ret);
+               goto err_submit;
        }
 
-       return status;
+       return 0;
+
+err_submit:
+       priv->int_buf.in_use = false;
+err:
+       return ret;
 }
 
 static void vnt_submit_rx_urb_complete(struct urb *urb)
@@ -215,12 +228,13 @@ static void vnt_submit_rx_urb_complete(struct urb *urb)
 
 int vnt_submit_rx_urb(struct vnt_private *priv, struct vnt_rcb *rcb)
 {
-       int status = 0;
+       int ret = 0;
        struct urb *urb = rcb->urb;
 
        if (!rcb->skb) {
                dev_dbg(&priv->usb->dev, "rcb->skb is null\n");
-               return status;
+               ret = -EINVAL;
+               goto end;
        }
 
        usb_fill_bulk_urb(urb,
@@ -231,15 +245,16 @@ int vnt_submit_rx_urb(struct vnt_private *priv, struct vnt_rcb *rcb)
                          vnt_submit_rx_urb_complete,
                          rcb);
 
-       status = usb_submit_urb(urb, GFP_ATOMIC);
-       if (status) {
-               dev_dbg(&priv->usb->dev, "Submit Rx URB failed %d\n", status);
-               return STATUS_FAILURE;
+       ret = usb_submit_urb(urb, GFP_ATOMIC);
+       if (ret) {
+               dev_dbg(&priv->usb->dev, "Submit Rx URB failed %d\n", ret);
+               goto end;
        }
 
        rcb->in_use = true;
 
-       return status;
+end:
+       return ret;
 }
 
 static void vnt_tx_context_complete(struct urb *urb)

diff --git a/drivers/staging/vt6656/usbpipe.h b/drivers/staging/vt6656/usbpipe.h
index 2910ca5..95147ec 100644 (file)
--- a/drivers/staging/vt6656/usbpipe.h
+++ b/drivers/staging/vt6656/usbpipe.h
@@ -23,8 +23,8 @@ int vnt_control_out(struct vnt_private *priv, u8 request, u16 value,
 int vnt_control_in(struct vnt_private *priv, u8 request, u16 value,
                   u16 index, u16 length,  u8 *buffer);
 
-void vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 ref_off, u8 data);
-void vnt_control_in_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 *data);
+int vnt_control_out_u8(struct vnt_private *priv, u8 reg, u8 ref_off, u8 data);
+int vnt_control_in_u8(struct vnt_private *priv, u8 reg, u8 reg_off, u8 *data);
 
 int vnt_start_interrupt_urb(struct vnt_private *priv);
 int vnt_submit_rx_urb(struct vnt_private *priv, struct vnt_rcb *rcb);