[PATCH 03/15] usb: serial: ch314: use usb_control_msg_recv() and usb_control_msg_send()

From: Himadri Pandya
Date: Wed Nov 04 2020 - 01:47:50 EST


The new usb_control_msg_recv() and usb_control_msg_send() nicely wraps
usb_control_msg() with proper error check. Hence use the wrappers
instead of calling usb_control_msg() directly.

Signed-off-by: Himadri Pandya <himadrispandya@xxxxxxxxx>
---
drivers/usb/serial/ch341.c | 45 ++++++++++++--------------------------
1 file changed, 14 insertions(+), 31 deletions(-)

diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c
index a2e2f56c88cd..58c5d3ce4f75 100644
--- a/drivers/usb/serial/ch341.c
+++ b/drivers/usb/serial/ch341.c
@@ -111,10 +111,10 @@ static int ch341_control_out(struct usb_device *dev, u8 request,
dev_dbg(&dev->dev, "%s - (%02x,%04x,%04x)\n", __func__,
request, value, index);

- r = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
- value, index, NULL, 0, DEFAULT_TIMEOUT);
- if (r < 0)
+ r = usb_control_msg_send(dev, 0, request, USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE | USB_DIR_OUT, value, index,
+ NULL, 0, DEFAULT_TIMEOUT, GFP_KERNEL);
+ if (r)
dev_err(&dev->dev, "failed to send control message: %d\n", r);

return r;
@@ -129,23 +129,14 @@ static int ch341_control_in(struct usb_device *dev,
dev_dbg(&dev->dev, "%s - (%02x,%04x,%04x,%u)\n", __func__,
request, value, index, bufsize);

- r = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
- value, index, buf, bufsize, DEFAULT_TIMEOUT);
- if (r < (int)bufsize) {
- if (r >= 0) {
- dev_err(&dev->dev,
- "short control message received (%d < %u)\n",
- r, bufsize);
- r = -EIO;
- }
-
+ r = usb_control_msg_recv(dev, 0, request, USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE | USB_DIR_IN, value, index,
+ buf, bufsize, DEFAULT_TIMEOUT, GFP_KERNEL);
+ if (r)
dev_err(&dev->dev, "failed to receive control message: %d\n",
r);
- return r;
- }

- return 0;
+ return r;
}

#define CH341_CLKRATE 48000000
@@ -343,22 +334,18 @@ static int ch341_detect_quirks(struct usb_serial_port *port)
struct usb_device *udev = port->serial->dev;
const unsigned int size = 2;
unsigned long quirks = 0;
- char *buffer;
+ u8 buffer[2];
int r;

- buffer = kmalloc(size, GFP_KERNEL);
- if (!buffer)
- return -ENOMEM;
-
/*
* A subset of CH34x devices does not support all features. The
* prescaler is limited and there is no support for sending a RS232
* break condition. A read failure when trying to set up the latter is
* used to detect these devices.
*/
- r = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0), CH341_REQ_READ_REG,
- USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN,
- CH341_REG_BREAK, 0, buffer, size, DEFAULT_TIMEOUT);
+ r = usb_control_msg_recv(udev, 0, CH341_REQ_READ_REG, USB_TYPE_VENDOR |
+ USB_RECIP_DEVICE | USB_DIR_IN, CH341_REG_BREAK,
+ 0, &buffer, size, DEFAULT_TIMEOUT, GFP_KERNEL);
if (r == -EPIPE) {
dev_info(&port->dev, "break control not supported, using simulated break\n");
quirks = CH341_QUIRK_LIMITED_PRESCALER | CH341_QUIRK_SIMULATE_BREAK;
@@ -366,17 +353,13 @@ static int ch341_detect_quirks(struct usb_serial_port *port)
goto out;
}

- if (r != size) {
- if (r >= 0)
- r = -EIO;
+ if (r) {
dev_err(&port->dev, "failed to read break control: %d\n", r);
goto out;
}

r = 0;
out:
- kfree(buffer);
-
if (quirks) {
dev_dbg(&port->dev, "enabling quirk flags: 0x%02lx\n", quirks);
priv->quirks |= quirks;
--
2.17.1