[PATCH] i2c: i2c-dev: Fixed warnings generated by checkpatch tool

Cezar Chiru
2025-09-06T14:31:35Z

Fixed all warnings in i2c-dev.c file in drivers/i2c/ folder
The errors were: missing '*' from multiple line comment blocks,
missing new blank line after declarations and found 'unsigned'
instead of 'unsigned int'.
My motivation was to fix all possible warnings and errors from
/drivers/i2c/ subsystem. I will skip false positives.
Testing:
* Built kernel with I2C_CHARDEV=y + my patch on and it succeeded.
Date of last git pull: 06-September-2025 around 12:00 UTC + 03:00
Latest commit SHA: d1d10cea0895
Build succeeded
* Installed kernel and external modules on my laptop with Ubuntu 24
* Checked dmesg for i2c-dev using grep and checked for errors or
success. Found 1 line related to i2c_dev:
[ 0.662406] i2c_dev: i2c /dev entries driver

Signed-off-by: Cezar Chiru <chiru.cezar.89@gmail.com>
---
drivers/i2c/i2c-dev.c | 51 +++++++++++++++++++++++++++----------------
1 file changed, 32 insertions(+), 19 deletions(-)

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index e9577f920286..0902b7b9cca6 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -1,16 +1,18 @@
// SPDX-License-Identifier: GPL-2.0-or-later
/*
- i2c-dev.c - i2c-bus driver, char device interface
-
- Copyright (C) 1995-97 Simon G. Vogl
- Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
- Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
-
-*/
+ * i2c-dev.c - i2c-bus driver, char device interface
+ *
+ * Copyright (C) 1995-97 Simon G. Vogl
+ * Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
+ * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
+ *
+ */

-/* Note that this is a complete rewrite of Simon Vogl's i2c-dev module.
- But I have used so much of his original code and ideas that it seems
- only fair to recognize him as co-author -- Frodo */
+/*
+ * Note that this is a complete rewrite of Simon Vogl's i2c-dev module.
+ * But I have used so much of his original code and ideas that it seems
+ * only fair to recognize him as co-author -- Frodo
+ */

/* The I2C_RDWR ioctl code is written by Kolja Waschk <waschk@telos.de> */

@@ -50,7 +52,7 @@ struct i2c_dev {
static LIST_HEAD(i2c_dev_list);
static DEFINE_SPINLOCK(i2c_dev_list_lock);

-static struct i2c_dev *i2c_dev_get_by_minor(unsigned index)
+static struct i2c_dev *i2c_dev_get_by_minor(unsigned int index)
{
struct i2c_dev *i2c_dev;

@@ -222,9 +224,11 @@ static int i2cdev_check_mux_children(struct device *dev, void *addrp)
return result;
}

-/* This address checking function differs from the one in i2c-core
- in that it considers an address with a registered device, but no
- driver bound to it, as NOT busy. */
+/*
+ * This address checking function differs from the one in i2c-core
+ * in that it considers an address with a registered device, but no
+ * driver bound to it, as NOT busy.
+ */
static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
{
struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter);
@@ -241,7 +245,7 @@ static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
}

static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client,
- unsigned nmsgs, struct i2c_msg *msgs)
+ unsigned int nmsgs, struct i2c_msg *msgs)
{
u8 __user **data_ptrs;
int i, res;
@@ -297,6 +301,7 @@ static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client,
}
if (res < 0) {
int j;
+
for (j = 0; j < i; ++j)
kfree(msgs[j].buf);
kfree(data_ptrs);
@@ -337,8 +342,10 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
size);
return -EINVAL;
}
- /* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1,
- so the check is valid if size==I2C_SMBUS_QUICK too. */
+ /*
+ * Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1,
+ * so the check is valid if size==I2C_SMBUS_QUICK too.
+ */
if ((read_write != I2C_SMBUS_READ) &&
(read_write != I2C_SMBUS_WRITE)) {
dev_dbg(&client->adapter->dev,
@@ -380,8 +387,10 @@ static noinline int i2cdev_ioctl_smbus(struct i2c_client *client,
return -EFAULT;
}
if (size == I2C_SMBUS_I2C_BLOCK_BROKEN) {
- /* Convert old I2C block commands to the new
- convention. This preserves binary compatibility. */
+ /*
+ * Convert old I2C block commands to the new
+ * convention. This preserves binary compatibility.
+ */
size = I2C_SMBUS_I2C_BLOCK_DATA;
if (read_write == I2C_SMBUS_READ)
temp.block[0] = I2C_SMBUS_BLOCK_MAX;
@@ -471,6 +480,7 @@ static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

case I2C_SMBUS: {
struct i2c_smbus_ioctl_data data_arg;
+
if (copy_from_user(&data_arg,
(struct i2c_smbus_ioctl_data __user *) arg,
sizeof(struct i2c_smbus_ioctl_data)))
@@ -531,6 +541,7 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
{
struct i2c_client *client = file->private_data;
unsigned long funcs;
+
switch (cmd) {
case I2C_FUNCS:
funcs = i2c_get_functionality(client->adapter);
@@ -560,6 +571,7 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
p = compat_ptr(rdwr_arg.msgs);
for (i = 0; i < rdwr_arg.nmsgs; i++) {
struct i2c_msg32 umsg;
+
if (copy_from_user(&umsg, p + i, sizeof(umsg))) {
kfree(rdwr_pa);
return -EFAULT;
@@ -578,6 +590,7 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
}
case I2C_SMBUS: {
struct i2c_smbus_ioctl_data32 data32;
+
if (copy_from_user(&data32,
(void __user *) arg,
sizeof(data32)))
--
2.43.0