2020-01-16 13:28:46

by Srinivas Neeli

Subject: [PATCH 1/9] watchdog: of_xilinx_wdt: Add comment to spinlock

From: Srinivas Goud <[email protected]>

Based on checkpatch every spinlock should be documented.
The patch is fixing this issue:
./scripts/checkpatch.pl --strict -f drivers/watchdog/of_xilinx_wdt.c
CHECK: spinlock_t definition without comment
+ spinlock_t spinlock;

Signed-off-by: Srinivas Goud <[email protected]>
Signed-off-by: Michal Simek <[email protected]>
---
drivers/watchdog/of_xilinx_wdt.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/watchdog/of_xilinx_wdt.c b/drivers/watchdog/of_xilinx_wdt.c
index 7fe4f7c3f7ce..00549164b3d7 100644
--- a/drivers/watchdog/of_xilinx_wdt.c
+++ b/drivers/watchdog/of_xilinx_wdt.c
@@ -40,7 +40,7 @@
struct xwdt_device {
void __iomem *base;
u32 wdt_interval;
- spinlock_t spinlock;
+ spinlock_t spinlock; /* spinlock for register handling */
struct watchdog_device xilinx_wdt_wdd;
struct clk *clk;
};
--
2.7.4

2020-01-16 15:50:30

by Guenter Roeck

Subject: Re: [PATCH 1/9] watchdog: of_xilinx_wdt: Add comment to spinlock

On Thu, Jan 16, 2020 at 06:56:49PM +0530, Srinivas Neeli wrote:
> From: Srinivas Goud <[email protected]>
>
> Based on checkpatch every spinlock should be documented.
> The patch is fixing this issue:
> ./scripts/checkpatch.pl --strict -f drivers/watchdog/of_xilinx_wdt.c
> CHECK: spinlock_t definition without comment
> + spinlock_t spinlock;

One of the most useless feedback messages from checkpatch.

>
> Signed-off-by: Srinivas Goud <[email protected]>
> Signed-off-by: Michal Simek <[email protected]>
> ---
> drivers/watchdog/of_xilinx_wdt.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/watchdog/of_xilinx_wdt.c b/drivers/watchdog/of_xilinx_wdt.c
> index 7fe4f7c3f7ce..00549164b3d7 100644
> --- a/drivers/watchdog/of_xilinx_wdt.c
> +++ b/drivers/watchdog/of_xilinx_wdt.c
> @@ -40,7 +40,7 @@
> struct xwdt_device {
> void __iomem *base;
> u32 wdt_interval;
> - spinlock_t spinlock;
> + spinlock_t spinlock; /* spinlock for register handling */

I don't see the added value here. Besides, what does the lock actually do ?
Watchdog drivers are single-open, so it seems quite difficult for any
of the protected functions to be called multiple times. The spinlock doesn't
disable interrupts, so register accesses by other drivers are still possible.
What am I missing ?

Guenter

> struct watchdog_device xilinx_wdt_wdd;
> struct clk *clk;
> };
> --
> 2.7.4
>