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 <abbotti@xxxxxxxxx>
---
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
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