| Message ID | 1392843415-17153-5-git-send-email-tyreld@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On 02/19/2014 12:56 PM, Tyrel Datwyler wrote: > Traditionally it has been drmgr's responsibilty to update the device tree > through the /proc/ppc64/ofdt interface after a suspend/resume operation. > This patchset however has modified suspend/resume ops to preform that update > entirely in the kernel during the resume. Therefore, a mechanism is required > for drmgr to determine who is responsible for the update. This patch adds a > show function to the "hibernate" attribute that returns 1 if the kernel > updates the device tree after the resume and 0 if drmgr is responsible. Ignore this one. Apparently, I forgot to clear it out of my patch directory before I resent. > > Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> > --- > arch/powerpc/platforms/pseries/suspend.c | 25 ++++++++++++++++++++++++- > 1 file changed, 24 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/platforms/pseries/suspend.c b/arch/powerpc/platforms/pseries/suspend.c > index 1d9c580..b87b978 100644 > --- a/arch/powerpc/platforms/pseries/suspend.c > +++ b/arch/powerpc/platforms/pseries/suspend.c > @@ -192,7 +192,30 @@ out: > return rc; > } > > -static DEVICE_ATTR(hibernate, S_IWUSR, NULL, store_hibernate); > +#define USER_DT_UPDATE 0 > +#define KERN_DT_UPDATE 1 > + > +/** > + * show_hibernate - Report device tree update responsibilty > + * @dev: subsys root device > + * @attr: device attribute struct > + * @buf: buffer > + * > + * Report whether a device tree update is performed by the kernel after a > + * resume, or if drmgr must coordinate the update from user space. > + * > + * Return value: > + * 0 if drmgr is to initiate update, and 1 otherwise > + **/ > +static ssize_t show_hibernate(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + return sprintf(buf, "%d\n", KERN_DT_UPDATE); > +} > + > +static DEVICE_ATTR(hibernate, S_IWUSR | S_IRUGO, > + show_hibernate, store_hibernate); > > static struct bus_type suspend_subsys = { > .name = "power", >
diff --git a/arch/powerpc/platforms/pseries/suspend.c b/arch/powerpc/platforms/pseries/suspend.c index 1d9c580..b87b978 100644 --- a/arch/powerpc/platforms/pseries/suspend.c +++ b/arch/powerpc/platforms/pseries/suspend.c @@ -192,7 +192,30 @@ out: return rc; } -static DEVICE_ATTR(hibernate, S_IWUSR, NULL, store_hibernate); +#define USER_DT_UPDATE 0 +#define KERN_DT_UPDATE 1 + +/** + * show_hibernate - Report device tree update responsibilty + * @dev: subsys root device + * @attr: device attribute struct + * @buf: buffer + * + * Report whether a device tree update is performed by the kernel after a + * resume, or if drmgr must coordinate the update from user space. + * + * Return value: + * 0 if drmgr is to initiate update, and 1 otherwise + **/ +static ssize_t show_hibernate(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", KERN_DT_UPDATE); +} + +static DEVICE_ATTR(hibernate, S_IWUSR | S_IRUGO, + show_hibernate, store_hibernate); static struct bus_type suspend_subsys = { .name = "power",
Traditionally it has been drmgr's responsibilty to update the device tree through the /proc/ppc64/ofdt interface after a suspend/resume operation. This patchset however has modified suspend/resume ops to preform that update entirely in the kernel during the resume. Therefore, a mechanism is required for drmgr to determine who is responsible for the update. This patch adds a show function to the "hibernate" attribute that returns 1 if the kernel updates the device tree after the resume and 0 if drmgr is responsible. Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> --- arch/powerpc/platforms/pseries/suspend.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-)