Re: [PATCH v3 2/2] drivers: watchdog: Add StarFive Watchdog driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 2/26/23 22:45, Xingyu Wu wrote:
On 2023/2/27 14:36, Guenter Roeck wrote:
On 2/26/23 22:26, Xingyu Wu wrote:
On 2023/2/24 23:18, Guenter Roeck wrote:
On 2/23/23 23:42, Xingyu Wu wrote:
On 2023/2/24 2:23, Guenter Roeck wrote:
On Mon, Feb 20, 2023 at 04:19:26PM +0800, Xingyu Wu wrote:
[...]
+
+    wdt->wdt_device.min_timeout = 1;
+    wdt->wdt_device.max_timeout = starfive_wdt_max_timeout(wdt);

      wdt->wdt_device.timeout = STARFIVE_WDT_DEFAULT_TIME;

should be set here. Otherwise the warning below would always be seen
if the module parameter is not set.

+
+    watchdog_set_drvdata(&wdt->wdt_device, wdt);
+
+    /*
+     * see if we can actually set the requested heartbeat,
+     * and if not, try the default value.
+     */
+    watchdog_init_timeout(&wdt->wdt_device, heartbeat, dev);
+    if (wdt->wdt_device.timeout == 0 ||

If wdt->wdt_device.timeout is pre-initialized, it will never be 0 here.

+        wdt->wdt_device.timeout > wdt->wdt_device.max_timeout) {

That won't happen because watchdog_init_timeout() validates it and does
not update the value if it is out of range.

+        dev_warn(dev, "heartbeat value out of range, default %d used\n",
+             STARFIVE_WDT_DEFAULT_TIME);
+        wdt->wdt_device.timeout = STARFIVE_WDT_DEFAULT_TIME;

And this is then unnecessary. wdt->wdt_device.timeout will always be
valid if it was pre-initialized.

It is changed to be this at beginning of the driver:

static int heartbeat = STARFIVE_WDT_DEFAULT_TIME;


No, this is wrong. The static variable should be set to 0 to indicate
"use default".

and it is changed to be this here:

ret = watchdog_init_timeout(&wdt->wdt_device, heartbeat, dev);
if (ret)
      return ret;

Would that be better?


No, it is worse, because it would not instantiate the watchdog at all
if a bad heartbeat is provided.


So instantiate the watchdog with hearbeat first. And if this wrong, use default timeout.
:
if (watchdog_init_timeout(&wdt->wdt_device, heartbeat, dev))
     wdt->wdt_device.timeout = STARFIVE_WDT_DEFAULT_TIME;


I am kind of lost why you have to make it that complicated.
Just pre-initialize wdt->wdt_device.timeout like all the other drivers do,
and as I had suggested earlier.


So you mean just use :
wdt->wdt_device.timeout = STARFIVE_WDT_DEFAULT_TIME;
to initialize watchdog directly?


Yes, as I had suggested before, before calling watchdog_init_timeout().

Guenter

Best regards,
Xingyu Wu




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux