Re: [PATCH v6 3/5] watchdog: at91sam9_wdt: add device tree support

[Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>]

On 17:04 Tue 02 Oct     , Fabio Porcedda wrote:
> On Mon, Oct 1, 2012 at 3:06 PM, Andrew Lunn <andrew@lunn.ch> wrote:
> > On Mon, Oct 01, 2012 at 02:54:55PM +0200, Fabio Porcedda wrote:
> >> On Mon, Oct 1, 2012 at 2:48 PM, Fabio Porcedda <fabio.porcedda@gmail.com> wrote:
> >> > On Mon, Oct 1, 2012 at 2:45 PM, Andrew Lunn <andrew@lunn.ch> wrote:
> >> >> On Mon, Oct 01, 2012 at 02:24:39PM +0200, Fabio Porcedda wrote:
> >> >>> Tested on an at91sam9260 board (evk-pro3)
> >> >>>
> >> >>> Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
> >> >>> ---
> >> >>>  .../devicetree/bindings/watchdog/atmel-wdt.txt      | 19 +++++++++++++++++++
> >> >>>  drivers/watchdog/at91sam9_wdt.c                     | 21 +++++++++++++++++++++
> >> >>>  2 files changed, 40 insertions(+)
> >> >>>  create mode 100644 Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> >> >>>
> >> >>> diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> >> >>> new file mode 100644
> >> >>> index 0000000..65c1755
> >> >>> --- /dev/null
> >> >>> +++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> >> >>> @@ -0,0 +1,19 @@
> >> >>> +* Atmel Watchdog Timers
> >> >>> +
> >> >>> +** at91sam9-wdt
> >> >>> +
> >> >>> +Required properties:
> >> >>> +- compatible: must be "atmel,at91sam9260-wdt".
> >> >>> +- reg: physical base address of the controller and length of memory mapped
> >> >>> +  region.
> >> >>> +
> >> >>> +Optional properties:
> >> >>> +- timeout: contains the watchdog timeout in seconds.
> >> >>> +
> >> >>> +Example:
> >> >>> +
> >> >>> +     watchdog@fffffd40 {
> >> >>> +             compatible = "atmel,at91sam9260-wdt";
> >> >>> +             reg = <0xfffffd40 0x10>;
> >> >>> +             timeout = <10>;
> >> >>> +     };
> >> >>> diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
> >> >>> index 05e1be8..c9e6bfa 100644
> >> >>> --- a/drivers/watchdog/at91sam9_wdt.c
> >> >>> +++ b/drivers/watchdog/at91sam9_wdt.c
> >> >>> @@ -32,6 +32,7 @@
> >> >>>  #include <linux/timer.h>
> >> >>>  #include <linux/bitops.h>
> >> >>>  #include <linux/uaccess.h>
> >> >>> +#include <linux/of.h>
> >> >>>
> >> >>>  #include "at91sam9_wdt.h"
> >> >>>
> >> >>> @@ -254,6 +255,14 @@ static struct miscdevice at91wdt_miscdev = {
> >> >>>       .fops           = &at91wdt_fops,
> >> >>>  };
> >> >>>
> >> >>> +static inline void __init at91wdt_probe_dt(struct device_node *node)
> >> >>> +{
> >> >>> +     if (!node)
> >> >>> +             return;
> >> >>> +
> >> >>> +     of_property_read_u32(node, "timeout", &heartbeat);
> >> >>> +}
> >> >>> +
> >> >>
> >> >> In patch #1 you add a function to do this, and then you don't make use
> >> >> of it here ?
> >> >>
> >> >> Or am i missing something?
> >> >
> >> > I'm using it on the patch #2 for the orion_wdt driver.
> >> > Do you think it's better to join the #1 and the #2 patch?
> >> >
> >> > Best regards
> >> > --
> >> > Fabio Porcedda
> >>
> >> I'm sorry, only now i understand your question.
> >> The at91sam9_wdt driver don't use the watchdog core framework si i
> >> can't use that function cleanly.
> >
> >> The patch #1 and #2 are for introducing the same property as the
> >> at91sam9_wdt driver.
> >
> > So maybe split this up into two different patchsets. One patchset to
> > add the helper function, and the use of this helper to all watchdog
> > divers that can use it. I think the following drivers should be
> > modified:
> >
> > orion_wdt.c
> > pnx4008_wdt.c
> > s3c2410_wdt.c
> >
> > In a second patchset, convert the AT91SAM9 driver over to the watchdog
> > core framework, and then use the helper function.
> 
> I was thinking to add a more generic helper function like this:
> 
> static inline void watchdog_get_dttimeout(struct device_node *node,
> u32 *timeout)
> {
> 	if (node)
> 		of_property_read_u32(node, "timeout", &wdd->timeout);
> }
> 
> This way i can use this helper function in the at91sam9_wdt driver too.
> What do you think?
timeout_sec and this can be move at of.h level

as this is not watchdog framework secific

Best Regards,
J.