[PATCH 8/8] Input: usbtouchscreen - switch to using __free() cleanup facility

From: Dmitry Torokhov
Date: Fri Jul 12 2024 - 01:21:30 EST


Use __free(kfree) cleanup facility when allocating temporary buffers
for USB transfers.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
drivers/input/touchscreen/usbtouchscreen.c | 90 ++++++++--------------
1 file changed, 33 insertions(+), 57 deletions(-)

diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 0015f0a6de01..7567efabe014 100644
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -167,9 +167,8 @@ static const struct usbtouch_device_info e2i_dev_info = {

static int egalax_init(struct usbtouch_usb *usbtouch)
{
- int ret, i;
- unsigned char *buf;
struct usb_device *udev = interface_to_usbdev(usbtouch->interface);
+ int ret, i;

/*
* An eGalax diagnostic packet kicks the device into using the right
@@ -177,7 +176,7 @@ static int egalax_init(struct usbtouch_usb *usbtouch)
* read later and ignored.
*/

- buf = kmalloc(3, GFP_KERNEL);
+ u8 *buf __free(kfree) = kmalloc(3, GFP_KERNEL);
if (!buf)
return -ENOMEM;

@@ -191,17 +190,11 @@ static int egalax_init(struct usbtouch_usb *usbtouch)
USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
0, 0, buf, 3,
USB_CTRL_SET_TIMEOUT);
- if (ret >= 0) {
- ret = 0;
- break;
- }
if (ret != -EPIPE)
break;
}

- kfree(buf);
-
- return ret;
+ return ret < 0 ? ret : 0;
}

static int egalax_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
@@ -358,10 +351,9 @@ static int mtouch_get_fw_revision(struct usbtouch_usb *usbtouch)
{
struct usb_device *udev = interface_to_usbdev(usbtouch->interface);
struct mtouch_priv *priv = usbtouch->priv;
- u8 *buf;
int ret;

- buf = kzalloc(MTOUCHUSB_REQ_CTRLLR_ID_LEN, GFP_NOIO);
+ u8 *buf __free(kfree) = kzalloc(MTOUCHUSB_REQ_CTRLLR_ID_LEN, GFP_NOIO);
if (!buf)
return -ENOMEM;

@@ -373,18 +365,13 @@ static int mtouch_get_fw_revision(struct usbtouch_usb *usbtouch)
if (ret != MTOUCHUSB_REQ_CTRLLR_ID_LEN) {
dev_warn(&usbtouch->interface->dev,
"Failed to read FW rev: %d\n", ret);
- ret = ret < 0 ? ret : -EIO;
- goto free;
+ return ret < 0 ? ret : -EIO;
}

priv->fw_rev_major = buf[3];
priv->fw_rev_minor = buf[4];

- ret = 0;
-
-free:
- kfree(buf);
- return ret;
+ return 0;
}

static int mtouch_alloc(struct usbtouch_usb *usbtouch)
@@ -636,24 +623,23 @@ static const struct usbtouch_device_info gunze_dev_info = {
static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
{
struct usb_device *dev = interface_to_usbdev(usbtouch->interface);
- int ret = -ENOMEM;
- unsigned char *buf;
+ int ret;

- buf = kmalloc(2, GFP_NOIO);
+ u8 *buf __free(kfree) = kmalloc(2, GFP_NOIO);
if (!buf)
- goto err_nobuf;
+ return -ENOMEM;
+
/* reset */
buf[0] = buf[1] = 0xFF;
ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
- TSC10_CMD_RESET,
- USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
- 0, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
+ TSC10_CMD_RESET,
+ USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ 0, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
if (ret < 0)
- goto err_out;
- if (buf[0] != 0x06) {
- ret = -ENODEV;
- goto err_out;
- }
+ return ret;
+
+ if (buf[0] != 0x06)
+ return -ENODEV;

/* TSC-25 data sheet specifies a delay after the RESET command */
msleep(150);
@@ -661,28 +647,22 @@ static int dmc_tsc10_init(struct usbtouch_usb *usbtouch)
/* set coordinate output rate */
buf[0] = buf[1] = 0xFF;
ret = usb_control_msg(dev, usb_rcvctrlpipe (dev, 0),
- TSC10_CMD_RATE,
- USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
- TSC10_RATE_150, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
+ TSC10_CMD_RATE,
+ USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ TSC10_RATE_150, 0, buf, 2, USB_CTRL_SET_TIMEOUT);
if (ret < 0)
- goto err_out;
- if ((buf[0] != 0x06) && (buf[0] != 0x15 || buf[1] != 0x01)) {
- ret = -ENODEV;
- goto err_out;
- }
+ return ret;
+
+ if (buf[0] != 0x06 && (buf[0] != 0x15 || buf[1] != 0x01))
+ return -ENODEV;

/* start sending data */
- ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
- TSC10_CMD_DATA1,
- USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
- 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
-err_out:
- kfree(buf);
-err_nobuf:
- return ret;
+ return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
+ TSC10_CMD_DATA1,
+ USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
+ 0, 0, NULL, 0, USB_CTRL_SET_TIMEOUT);
}

-
static int dmc_tsc10_read_data(struct usbtouch_usb *dev, unsigned char *pkt)
{
dev->x = ((pkt[2] & 0x03) << 8) | pkt[1];
@@ -992,7 +972,6 @@ static int nexio_init(struct usbtouch_usb *usbtouch)
struct nexio_priv *priv = usbtouch->priv;
int ret = -ENOMEM;
int actual_len, i;
- unsigned char *buf;
char *firmware_ver = NULL, *device_name = NULL;
int input_ep = 0, output_ep = 0;

@@ -1008,9 +987,9 @@ static int nexio_init(struct usbtouch_usb *usbtouch)
if (!input_ep || !output_ep)
return -ENXIO;

- buf = kmalloc(NEXIO_BUFSIZE, GFP_NOIO);
+ u8 *buf __free(kfree) = kmalloc(NEXIO_BUFSIZE, GFP_NOIO);
if (!buf)
- goto out_buf;
+ return -ENOMEM;

/* two empty reads */
for (i = 0; i < 2; i++) {
@@ -1018,7 +997,7 @@ static int nexio_init(struct usbtouch_usb *usbtouch)
buf, NEXIO_BUFSIZE, &actual_len,
NEXIO_TIMEOUT);
if (ret < 0)
- goto out_buf;
+ return ret;
}

/* send init command */
@@ -1027,7 +1006,7 @@ static int nexio_init(struct usbtouch_usb *usbtouch)
buf, sizeof(nexio_init_pkt), &actual_len,
NEXIO_TIMEOUT);
if (ret < 0)
- goto out_buf;
+ return ret;

/* read replies */
for (i = 0; i < 3; i++) {
@@ -1058,11 +1037,8 @@ static int nexio_init(struct usbtouch_usb *usbtouch)
usb_fill_bulk_urb(priv->ack, dev, usb_sndbulkpipe(dev, output_ep),
priv->ack_buf, sizeof(nexio_ack_pkt),
nexio_ack_complete, usbtouch);
- ret = 0;

-out_buf:
- kfree(buf);
- return ret;
+ return 0;
}

static void nexio_exit(struct usbtouch_usb *usbtouch)
--
2.45.2.993.g49e7a77208-goog