On Tue, Feb 13, 2018 at 01:55:49PM -0800, Guenter Roeck wrote: > On Tue, Feb 13, 2018 at 02:36:48PM -0700, Jerry Hoemann wrote: > > > > > > > > > > dev_dbg() > > > > I think you are proposing I do: > > > > dev_dbg(dev->parent, "settimeout = %d\n", val); > > > > This raises the issue that I didn't set parent and I believe I should have. > > > Correct.
Will fix. > > > > retval = hpwdt_init_nmi_decoding(dev); > > > > if (retval != 0) > > > > goto error_init_nmi_decoding; > > > > > > > > - retval = misc_register(&hpwdt_miscdev); > > > > + retval = watchdog_register_device(&hpwdt_dev); > > > > if (retval < 0) { > > > > - dev_warn(&dev->dev, > > > > - "Unable to register miscdev on minor=%d > > > > (err=%d).\n", > > > > - WATCHDOG_MINOR, retval); > > > > - goto error_misc_register; > > > > + dev_warn(&dev->dev, "Unable to register hpe watchdog > > > > (err=%d).\n", retval); > > > > + goto error_wd_register; > > > > + } > > > > + > > > > + watchdog_set_nowayout(&hpwdt_dev, nowayout); > > > > + if (watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL)) { > > > > + dev_warn(&dev->dev, "Invalid soft_margin: %d. Using > > > > default\n", soft_margin); > > > > + soft_margin = DEFAULT_MARGIN; > > > > } > > > > > > In this case watchdog_init_timout() will: > > > 1) Check if soft_margin is valid > > > 2) if not, keep hpwdt_dev.timout intact (which is already set in > > > declaration of hpwdt_dev) > > > > > > So we could remove the condition and only keep > > > watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL); > > > > > > > > > Also, we need to set an invalid initial value for soft_margin to make > > > the logic for watchdog_init_timeout work. > > > > > > i.e > > > - static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ > > > + static unsigned int soft_margin; > > > > > > I don't see the core printing a warning message if an invalid value > > is specified for soft_margin when loading the module. > > > > I don't mind the hpwdt module correcting an out of range parameter, but I > > don't think it should do so siliently. > > > > The point here is that setting soft_margin to 0 and setting the > timeout in the watchdog_device structure to DEFAULT_MARGIN > means that it is not necessary to override it on error. Yes, I don't need to set soft_margin = DEFAULT_MARGIN inside the conditional on watchdog_init_timeout. I was doing that to keep the value of soft_margin consistent with the value of hpwdt_dev.timeout so that it would show the current timeout value in sysfs. But, as you pointed out, the watchdog sysfs displays timeout. So, i don't need that asignment anymore. But, I want to keep the initialization: static unsigned int soft_margin = DEFAULT_MARGIN; Reasoning: I want soft_margin to be an optional parameter that defaults to DEFAULT_MARGIN without warning. If soft_margin is initialized to a value outside of the valid range, say N, the code can't tell the difference between the static value of N or if the module was loaded with the soft_margin=N. I only want to warn on the latter. > If you want to be verbose, you can still log a warning message > if the timeout provided by the module parameter is wrong. > > Anyway, this driver will presumably never support devicetree, > so the watchdog core will never read the timeout from there, > and this is not a showstopper. > -- ----------------------------------------------------------------------------- Jerry Hoemann Software Engineer Hewlett Packard Enterprise -----------------------------------------------------------------------------