Re: [PATCH 05/14] HID: i2c-hid: fix i2c_hid_dbg macro

From: Jean Delvare
Date: Tue Dec 04 2012 - 16:49:48 EST


On Tue, 4 Dec 2012 16:27:46 +0100, Benjamin Tissoires wrote:
> This avoids the problematic case:
>
> if (condition)
> i2c_hid_dbg(ihid, "Blah blah %d\n", i);
> else
> do_something_very_important();
>
> Which looks correct, however with the previous macro definition,
> this expands to the unexpected:
>
> if (condition) {
> if (debug) \
> dev_printk(KERN_DEBUG, &ihid->client->dev,
> "Blah blah %d\n", i);
> else
> do_something_very_important();
> }
>
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxx>
> ---
> drivers/hid/i2c-hid/i2c-hid.c | 8 +++++---
> 1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
> index 9ee6555..54950be 100644
> --- a/drivers/hid/i2c-hid/i2c-hid.c
> +++ b/drivers/hid/i2c-hid/i2c-hid.c
> @@ -50,9 +50,11 @@ static bool debug;
> module_param(debug, bool, 0444);
> MODULE_PARM_DESC(debug, "print a lot of debug information");
>
> -#define i2c_hid_dbg(ihid, fmt, arg...) \
> - if (debug) \
> - dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg)
> +#define i2c_hid_dbg(ihid, fmt, arg...) \
> +do { \
> + if (debug) \
> + dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
> +} while (0)
>
> struct i2c_hid_desc {
> __le16 wHIDDescLength;

Reviewed-by: Jean Delvare <khali@xxxxxxxxxxxx>

--
Jean Delvare
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