Bit 0 of `dw_wdt.in_use` is tested and set atomically to indicate that the watchdog has been opened exclusively. The other bits are unused. Some parts of the code also treat the whole of the `in_use` member as a boolean value.
In preparation for making use of the unused bits, rename the `in_use` member to `state`, define a new macro `DW_WDT_IN_USE` to identify bit 0 as the "in-use" bit, and replace conditional tests on the whole of `in_use` with single-bit tests on the appropriate bit of `state`. Signed-off-by: Ian Abbott <[email protected]> --- drivers/watchdog/dw_wdt.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c index 6ea0634..249ef09 100644 --- a/drivers/watchdog/dw_wdt.c +++ b/drivers/watchdog/dw_wdt.c @@ -59,10 +59,13 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " #define WDT_TIMEOUT (HZ / 2) +/* dw_wdt.state bit numbers */ +#define DW_WDT_IN_USE 0 + static struct { void __iomem *regs; struct clk *clk; - unsigned long in_use; + unsigned long state; unsigned long next_heartbeat; struct timer_list timer; int expect_close; @@ -160,7 +163,7 @@ static int dw_wdt_restart_handle(struct notifier_block *this, static void dw_wdt_ping(unsigned long data) { if (time_before(jiffies, dw_wdt.next_heartbeat) || - (!nowayout && !dw_wdt.in_use)) { + (!nowayout && !test_bit(DW_WDT_IN_USE, &dw_wdt.state))) { dw_wdt_keepalive(); mod_timer(&dw_wdt.timer, jiffies + WDT_TIMEOUT); } else @@ -169,7 +172,7 @@ static void dw_wdt_ping(unsigned long data) static int dw_wdt_open(struct inode *inode, struct file *filp) { - if (test_and_set_bit(0, &dw_wdt.in_use)) + if (test_and_set_bit(DW_WDT_IN_USE, &dw_wdt.state)) return -EBUSY; /* Make sure we don't get unloaded. */ @@ -273,7 +276,7 @@ static long dw_wdt_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) static int dw_wdt_release(struct inode *inode, struct file *filp) { - clear_bit(0, &dw_wdt.in_use); + clear_bit(DW_WDT_IN_USE, &dw_wdt.state); if (!dw_wdt.expect_close) { del_timer(&dw_wdt.timer); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
