On Mon, 2013-03-25 at 00:20 -0600, R, Durgadoss wrote: > > -----Original Message----- > > From: [email protected] [mailto:linux-pm- > > [email protected]] On Behalf Of Zhang Rui > > Sent: Monday, March 25, 2013 11:41 AM > > To: Eduardo Valentin > > Cc: [email protected]; [email protected] > > Subject: Re: [PATCH 1/2] thermal: introduce > > thermal_zone_lookup_temperature helper function > > > > On Fri, 2013-03-22 at 17:13 -0400, Eduardo Valentin wrote: > > > This patch adds a helper function to get temperature of > > > a thermal zone, based on the zone type name. > > > > > > It will perform a zone name lookup and return the last > > > sensor temperature reading. In case the zone is not found > > > or if the required parameters are invalid, it will return > > > the corresponding error code. > > > > > > Signed-off-by: Eduardo Valentin <[email protected]> > > > --- > > > drivers/thermal/thermal_sys.c | 32 > > ++++++++++++++++++++++++++++++++ > > > include/linux/thermal.h | 1 + > > > 2 files changed, 33 insertions(+), 0 deletions(-) > > > > > > diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c > > > index 5bd95d4..f0caa13 100644 > > > --- a/drivers/thermal/thermal_sys.c > > > +++ b/drivers/thermal/thermal_sys.c > > > @@ -1790,6 +1790,38 @@ void thermal_zone_device_unregister(struct > > thermal_zone_device *tz) > > > } > > > EXPORT_SYMBOL_GPL(thermal_zone_device_unregister); > > > > > > +/** > > > + * thermal_lookup_temperature - search for a zone and returns its > > temperature > > > + * @name: thermal zone name to fetch the temperature > > > + * @temperature: pointer to store the zone temperature, in case it is > > found > > > + * > > > + * When the zone is found, updates @temperature and returns 0. > > > + * > > > + * Return: -EINVAL in case of wrong parameters, -ENODEV in case the > > zone > > > + * is not found and 0 when it is successfully found. > > > + */ > > > +int thermal_zone_lookup_temperature(const char *name, int > > *temperature) > > > +{ > > > + struct thermal_zone_device *pos = NULL; > > > + bool found = false; > > > + > > > + if (!name || !temperature) > > > + return -EINVAL; > > > + > > > + mutex_lock(&thermal_list_lock); > > > + list_for_each_entry(pos, &thermal_tz_list, node) > > > + if (!strcmp(pos->type, name)) { > > > + found = true; > > > + break; > > > + } > > > + if (found) > > > + *temperature = pos->last_temperature; > > > + mutex_unlock(&thermal_list_lock); > > > + > > > + return found ? 0 : -ENODEV; > > > +} > > > +EXPORT_SYMBOL_GPL(thermal_zone_lookup_temperature); > > > + > > please do not use thermal zone type as the parameter because unique > > thermal zone type string is not a hard rule. > > Okay, agree with this. This is what I am implementing in > my changes as well. > > > If this is really needed, I'd prefer two APIs instead > > 1. struct thermal_zone_device * thermal_zone_get_zone_by_name(char > > *name); > > 2. int thermal_zone_get_temperature(struct thermal_zone_device *, int > > *temperature); > > Why do we need this second API? > If the driver has a 'tz' pointer, it can use tz->ops->get_temp > to retrieve the temperature, right ? >
probably it is because one driver want to get the temperature of a sensor registered by another driver. thanks, rui -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
