[1/3] snd-usb-6fire: Move DMA-buffer off of the stack

Commit Message

René Herman July 21, 2020, 6:48 a.m. UTC

snd-usb-fire currently fails its firmware load with "transfer buffer not dma
capable". Move said buffer off of the stack.

Signed-off-by: René Herman <[e-mail]>
---
 firmware.c | 95 ++++++++++++++++++++++++++----------------------------
 1 file changed, 46 insertions(+), 49 deletions(-)

Comments

Takashi Iwai July 21, 2020, 8 a.m. UTC | #1

On Tue, 21 Jul 2020 08:48:51 +0200,
René Herman wrote:
> 
> snd-usb-fire currently fails its firmware load with "transfer buffer not dma
> capable". Move said buffer off of the stack.
> 
> Signed-off-by: René Herman <[e-mail]>
> ---
>  firmware.c | 95 ++++++++++++++++++++++++++----------------------------
>  1 file changed, 46 insertions(+), 49 deletions(-)
> 
> diff --git a/firmware.c b/firmware.c
> index 69137c1..502653a 100644
> --- a/firmware.c
> +++ b/firmware.c
> @@ -355,63 +355,60 @@ static int usb6fire_fw_check(struct usb_interface *intf, const u8 *version)
>  
>  int usb6fire_fw_init(struct usb_interface *intf)
>  {
> -	int i;
> -	int ret;
>  	struct usb_device *device = interface_to_usbdev(intf);
> +	int ret, i;
> +
>  	/* buffer: 8 receiving bytes from device and
>  	 * sizeof(EP_W_MAX_PACKET_SIZE) bytes for non-const copy */
> -	u8 buffer[12];
> +	u8 *buffer = kmalloc(12, GFP_KERNEL);
> +
> +	if (!buffer)
> +		return -ENOMEM;
>  
>  	ret = usb6fire_fw_ezusb_read(device, 1, 0, buffer, 8);
>  	if (ret < 0) {
>  		dev_err(&intf->dev,
>  			"unable to receive device firmware state.\n");
> -		return ret;
> -	}
> -	if (buffer[0] != 0xeb || buffer[1] != 0xaa || buffer[2] != 0x55) {
> -		dev_err(&intf->dev,
> -			"unknown device firmware state received from device:");
> -		for (i = 0; i < 8; i++)
> -			printk(KERN_CONT "%02x ", buffer[i]);
> -		printk(KERN_CONT "\n");
> -		return -EIO;
> -	}

Could you rather change return with goto out (with ret variable set)?
In that way we can see what actually you changed more clearly.


thanks,

Takashi

Patch

diff --git a/firmware.c b/firmware.c
index 69137c1..502653a 100644
--- a/firmware.c
+++ b/firmware.c
@@ -355,63 +355,60 @@  static int usb6fire_fw_check(struct usb_interface *intf, const u8 *version)
 
 int usb6fire_fw_init(struct usb_interface *intf)
 {
-	int i;
-	int ret;
 	struct usb_device *device = interface_to_usbdev(intf);
+	int ret, i;
+
 	/* buffer: 8 receiving bytes from device and
 	 * sizeof(EP_W_MAX_PACKET_SIZE) bytes for non-const copy */
-	u8 buffer[12];
+	u8 *buffer = kmalloc(12, GFP_KERNEL);
+
+	if (!buffer)
+		return -ENOMEM;
 
 	ret = usb6fire_fw_ezusb_read(device, 1, 0, buffer, 8);
 	if (ret < 0) {
 		dev_err(&intf->dev,
 			"unable to receive device firmware state.\n");
-		return ret;
-	}
-	if (buffer[0] != 0xeb || buffer[1] != 0xaa || buffer[2] != 0x55) {
-		dev_err(&intf->dev,
-			"unknown device firmware state received from device:");
-		for (i = 0; i < 8; i++)
-			printk(KERN_CONT "%02x ", buffer[i]);
-		printk(KERN_CONT "\n");
-		return -EIO;
-	}
-	/* do we need fpga loader ezusb firmware? */
-	if (buffer[3] == 0x01) {
-		ret = usb6fire_fw_ezusb_upload(intf,
-				"6fire/dmx6firel2.ihx", 0, NULL, 0);
-		if (ret < 0)
-			return ret;
-		return FW_NOT_READY;
+		goto out;
 	}
-	/* do we need fpga firmware and application ezusb firmware? */
-	else if (buffer[3] == 0x02) {
-		ret = usb6fire_fw_check(intf, buffer + 4);
-		if (ret < 0)
-			return ret;
-		ret = usb6fire_fw_fpga_upload(intf, "6fire/dmx6firecf.bin");
-		if (ret < 0)
-			return ret;
-		memcpy(buffer, ep_w_max_packet_size,
-				sizeof(ep_w_max_packet_size));
-		ret = usb6fire_fw_ezusb_upload(intf, "6fire/dmx6fireap.ihx",
-				0x0003,	buffer, sizeof(ep_w_max_packet_size));
-		if (ret < 0)
-			return ret;
-		return FW_NOT_READY;
-	}
-	/* all fw loaded? */
-	else if (buffer[3] == 0x03)
-		return usb6fire_fw_check(intf, buffer + 4);
-	/* unknown data? */
-	else {
-		dev_err(&intf->dev,
-			"unknown device firmware state received from device: ");
-		for (i = 0; i < 8; i++)
-			printk(KERN_CONT "%02x ", buffer[i]);
-		printk(KERN_CONT "\n");
-		return -EIO;
+	if (buffer[0] == 0xeb && buffer[1] == 0xaa && buffer[2] == 0x55) {
+		/* do we need fpga loader ezusb firmware? */
+		if (buffer[3] == 1) {
+			ret = usb6fire_fw_ezusb_upload(intf,
+					"6fire/dmx6firel2.ihx", 0, NULL, 0);
+			if (ret >= 0)
+				ret = FW_NOT_READY;
+			goto out;
+		}
+		/* do we need fpga firmware and application ezusb firmware? */
+		if (buffer[3] == 2) {
+			ret = usb6fire_fw_check(intf, buffer + 4);
+			if (ret < 0)
+				goto out;
+			ret = usb6fire_fw_fpga_upload(intf, "6fire/dmx6firecf.bin");
+			if (ret < 0)
+				goto out;
+			memcpy(buffer, ep_w_max_packet_size,
+					sizeof(ep_w_max_packet_size));
+			ret = usb6fire_fw_ezusb_upload(intf, "6fire/dmx6fireap.ihx",
+					0x0003,	buffer, sizeof(ep_w_max_packet_size));
+			if (ret >= 0)
+				ret = FW_NOT_READY;
+			goto out;
+		}
+		/* all fw loaded? */
+		if (buffer[3] == 3) {
+			ret = usb6fire_fw_check(intf, buffer + 4);
+			goto out;
+		}
 	}
-	return 0;
+	dev_err(&intf->dev,
+		"unknown device firmware state received from device: ");
+	for (i = 0; i < 8; i++)
+		printk(KERN_CONT "%02x ", buffer[i]);
+	printk(KERN_CONT "\n");
+	ret = -EIO;
+
+out:	kfree(buffer);
+	return ret;
 }
-