diff mbox series

[v2,06/15] usb: misc: emi62: update to use usb_control_msg_send()

Message ID 20201130012925.2579632-1-anant.thazhemadam@gmail.com
State New
Headers show
Series drivers: usb: misc: update to use usb_control_msg_{send|recv}() | expand

Commit Message

Anant Thazhemadam Nov. 30, 2020, 1:29 a.m. UTC 
The newer usb_control_msg_{send|recv}() API are an improvement on the
existing usb_control_msg() as it ensures that a short read/write is treated
as an error, data can be used off the stack, and raw usb pipes need not be
created in the calling functions.
For this reason, the instance of usb_control_msg() has been replaced with
usb_control_msg_send() appropriately.

Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>
---
 drivers/usb/misc/emi62.c | 30 +++++++-----------------------
 1 file changed, 7 insertions(+), 23 deletions(-)

Comments

Johan Hovold Dec. 4, 2020, 2:43 p.m. UTC | #1 
On Mon, Nov 30, 2020 at 06:59:25AM +0530, Anant Thazhemadam wrote:
> The newer usb_control_msg_{send|recv}() API are an improvement on the

> existing usb_control_msg() as it ensures that a short read/write is treated

> as an error, data can be used off the stack, and raw usb pipes need not be

> created in the calling functions.

> For this reason, the instance of usb_control_msg() has been replaced with

> usb_control_msg_send() appropriately.

> 

> Signed-off-by: Anant Thazhemadam <anant.thazhemadam@gmail.com>

> ---


This driver looks like it shares origins with the emi26 one so the same
comments apply (and especially not put large structures on the stack).

Johan
diff mbox series

Patch

diff --git a/drivers/usb/misc/emi62.c b/drivers/usb/misc/emi62.c
index 3eea60437f56..6ac4e72d53e0 100644
--- a/drivers/usb/misc/emi62.c
+++ b/drivers/usb/misc/emi62.c
@@ -36,7 +36,7 @@ 
 #define INTERNAL_RAM(address)   (address <= MAX_INTERNAL_ADDRESS)
 
 static int emi62_writememory(struct usb_device *dev, int address,
-			     const unsigned char *data, int length,
+			     const void *data, int length,
 			     __u8 bRequest);
 static int emi62_set_reset(struct usb_device *dev, unsigned char reset_bit);
 static int emi62_load_firmware (struct usb_device *dev);
@@ -45,21 +45,11 @@  static void emi62_disconnect(struct usb_interface *intf);
 
 /* thanks to drivers/usb/serial/keyspan_pda.c code */
 static int emi62_writememory(struct usb_device *dev, int address,
-			     const unsigned char *data, int length,
+			     const void *data, int length,
 			     __u8 request)
 {
-	int result;
-	unsigned char *buffer =  kmemdup(data, length, GFP_KERNEL);
-
-	if (!buffer) {
-		dev_err(&dev->dev, "kmalloc(%d) failed.\n", length);
-		return -ENOMEM;
-	}
-	/* Note: usb_control_msg returns negative value on error or length of the
-	 * 		 data that was written! */
-	result = usb_control_msg (dev, usb_sndctrlpipe(dev, 0), request, 0x40, address, 0, buffer, length, 300);
-	kfree (buffer);
-	return result;
+	return usb_control_msg_send(dev, 0, request, 0x40, address,
+				    0, data, length, 300, GFP_KERNEL);
 }
 
 /* thanks to drivers/usb/serial/keyspan_pda.c code */
@@ -85,12 +75,9 @@  static int emi62_load_firmware (struct usb_device *dev)
 	int err = -ENOMEM;
 	int i;
 	__u32 addr;	/* Address to write */
-	__u8 *buf;
+	__u8 buf[FW_LOAD_SIZE];
 
 	dev_dbg(&dev->dev, "load_firmware\n");
-	buf = kmalloc(FW_LOAD_SIZE, GFP_KERNEL);
-	if (!buf)
-		goto wraperr;
 
 	err = request_ihex_firmware(&loader_fw, "emi62/loader.fw", &dev->dev);
 	if (err)
@@ -140,11 +127,11 @@  static int emi62_load_firmware (struct usb_device *dev)
 
 		/* intel hex records are terminated with type 0 element */
 		while (rec && (i + be16_to_cpu(rec->len) < FW_LOAD_SIZE)) {
-			memcpy(buf + i, rec->data, be16_to_cpu(rec->len));
+			memcpy(&buf[i], rec->data, be16_to_cpu(rec->len));
 			i += be16_to_cpu(rec->len);
 			rec = ihex_next_binrec(rec);
 		}
-		err = emi62_writememory(dev, addr, buf, i, ANCHOR_LOAD_FPGA);
+		err = emi62_writememory(dev, addr, &buf, i, ANCHOR_LOAD_FPGA);
 		if (err < 0)
 			goto wraperr;
 	} while (rec);
@@ -209,8 +196,6 @@  static int emi62_load_firmware (struct usb_device *dev)
 	release_firmware(bitstream_fw);
 	release_firmware(firmware_fw);
 
-	kfree(buf);
-
 	/* return 1 to fail the driver inialization
 	 * and give real driver change to load */
 	return 1;
@@ -223,7 +208,6 @@  static int emi62_load_firmware (struct usb_device *dev)
 	release_firmware(bitstream_fw);
 	release_firmware(firmware_fw);
 
-	kfree(buf);
 	dev_err(&dev->dev, "Error\n");
 	return err;
 }