Remove recalculation of offset from desc, where desc itself was calculated from offset.
There is no benefit from for the desc -> hwgpio conversion in this context. The only implicit benefit of the offset -> desc -> hwgpio is the range check in the offset -> desc, but where desc is required you still get that, and where desc isn't required it is simpler to perform the range check directly. Signed-off-by: Kent Gibson <[email protected]> --- drivers/gpio/gpiolib-cdev.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c index a727709b24a9..b6878fc87dfc 100644 --- a/drivers/gpio/gpiolib-cdev.c +++ b/drivers/gpio/gpiolib-cdev.c @@ -834,7 +834,6 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) void __user *ip = (void __user *)arg; struct gpio_desc *desc; __u32 offset; - int hwgpio; /* We fail any subsequent ioctl():s when the chip is gone */ if (!gc) @@ -862,12 +861,11 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; + /* this doubles as a range check on line_offset */ desc = gpiochip_get_desc(gc, lineinfo.line_offset); if (IS_ERR(desc)) return PTR_ERR(desc); - hwgpio = gpio_chip_hwgpio(desc); - gpio_desc_to_lineinfo(desc, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) @@ -883,13 +881,12 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) return -EFAULT; + /* this doubles as a range check on line_offset */ desc = gpiochip_get_desc(gc, lineinfo.line_offset); if (IS_ERR(desc)) return PTR_ERR(desc); - hwgpio = gpio_chip_hwgpio(desc); - - if (test_and_set_bit(hwgpio, gcdev->watched_lines)) + if (test_and_set_bit(lineinfo.line_offset, gcdev->watched_lines)) return -EBUSY; gpio_desc_to_lineinfo(desc, &lineinfo); @@ -902,13 +899,10 @@ static long gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg) if (copy_from_user(&offset, ip, sizeof(offset))) return -EFAULT; - desc = gpiochip_get_desc(gc, offset); - if (IS_ERR(desc)) - return PTR_ERR(desc); - - hwgpio = gpio_chip_hwgpio(desc); + if (offset >= gcdev->gdev->ngpio) + return -EINVAL; - if (!test_and_clear_bit(hwgpio, gcdev->watched_lines)) + if (!test_and_clear_bit(offset, gcdev->watched_lines)) return -EBUSY; return 0; -- 2.27.0
