| Message ID | 20201012135517.19468-3-frank@allwinnertech.com |
|---|---|
| State | New |
| Headers | show |
| Series | Introduce devm_pm_opp_set_* API | expand |
On 12-10-20, 21:55, Frank Lee wrote: > From: Yangtao Li <tiny.windzz@gmail.com> > > Add devres wrapper for dev_pm_opp_set_prop_name() to simplify driver > code. > > Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> > Signed-off-by: Yangtao Li <frank@allwinnertech.com> > --- > drivers/opp/core.c | 39 +++++++++++++++++++++++++++++++++++++++ > include/linux/pm_opp.h | 6 ++++++ > 2 files changed, 45 insertions(+) On a second thought I am looking at dropping this one as you haven't added any users yet and I am afraid it will stay unused.
On Wed, Oct 28, 2020 at 6:29 PM Viresh Kumar <viresh.kumar@linaro.org> wrote: > > On 12-10-20, 21:55, Frank Lee wrote: > > From: Yangtao Li <tiny.windzz@gmail.com> > > > > Add devres wrapper for dev_pm_opp_set_prop_name() to simplify driver > > code. > > > > Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> > > Signed-off-by: Yangtao Li <frank@allwinnertech.com> > > --- > > drivers/opp/core.c | 39 +++++++++++++++++++++++++++++++++++++++ > > include/linux/pm_opp.h | 6 ++++++ > > 2 files changed, 45 insertions(+) > > On a second thought I am looking at dropping this one as you haven't > added any users yet and I am afraid it will stay unused. Now it looks like that dev_pm_opp_set_prop_name() is used relatively less. Maybe we can wait until a caller, and then pick up the patch. MBR, Yangtao
On Wed, Oct 28, 2020 at 10:46 PM Viresh Kumar <viresh.kumar@linaro.org> wrote: > > On 28-10-20, 19:02, Frank Lee wrote: > > On Wed, Oct 28, 2020 at 6:29 PM Viresh Kumar <viresh.kumar@linaro.org> wrote: > > > > > > On 12-10-20, 21:55, Frank Lee wrote: > > > > From: Yangtao Li <tiny.windzz@gmail.com> > > > > > > > > Add devres wrapper for dev_pm_opp_set_prop_name() to simplify driver > > > > code. > > > > > > > > Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> > > > > Signed-off-by: Yangtao Li <frank@allwinnertech.com> > > > > --- > > > > drivers/opp/core.c | 39 +++++++++++++++++++++++++++++++++++++++ > > > > include/linux/pm_opp.h | 6 ++++++ > > > > 2 files changed, 45 insertions(+) > > > > > > On a second thought I am looking at dropping this one as you haven't > > > added any users yet and I am afraid it will stay unused. > > > > Now it looks like that dev_pm_opp_set_prop_name() is used relatively less. > > Maybe we can wait until a caller, and then pick up the patch. > > I am even wondering if we should be adding any of the devm_* helpers > for now to be honest. Even for the other one we have only one user. > Them major user of the OPP core is the CPU subsystem and it is never > going to use these devm_* helpers as the CPU device doesn't get bound > to a driver, it is rather a fake platform device which gets the > cpufreq drivers probed. So the only users of these devm_* helpers is > going to be non-CPU devices. Considering that we have only one user > right now, it may be better to just fix it instead of adding any of > the devm_* helpers. GPU is also a relatively large number of opp consumers. Most of the time, the dev_pm_opp_set_* functions will only be set once. If don't need the driver to dynamically manage and release the opp, it may be OK？ Yangtao
On 30-10-20, 19:19, Frank Lee wrote: > GPU is also a relatively large number of opp consumers. I was talking about the number of files or locations from which this routine (the devm_* variant) is going to get called. And it is one right now. And I don't see if any of the other callers are going to use it for now. > Most of the time, the dev_pm_opp_set_* functions will only be set once. Right. > If don't need the driver to dynamically manage and release the opp, it > may be OK？ Every call to dev_pm_opp_set_supported_hw() increases the ref count of the OPP table and if it isn't balanced with a call to dev_pm_opp_put_supported_hw(), then the OPP table will never get freed. So if the driver is a module and ends up creating an OPP table every time, then this will lead to leakage. The best way to fix this is by calling dev_pm_opp_put_supported_hw() from the right place and then we are good.
diff --git a/drivers/opp/core.c b/drivers/opp/core.c index b38852dde578..3263fa8302c9 100644 --- a/drivers/opp/core.c +++ b/drivers/opp/core.c @@ -1721,6 +1721,45 @@ void dev_pm_opp_put_prop_name(struct opp_table *opp_table) } EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name); +static void devm_pm_opp_put_prop_name(struct device *dev, void *res) +{ + dev_pm_opp_put_prop_name(*(struct opp_table **)res); +} + +/** + * devm_pm_opp_set_prop_name() - Set prop-extn name + * @dev: Device for which the prop-name has to be set. + * @name: name to postfix to properties. + * + * This is required only for the V2 bindings, and it enables a platform to + * specify the extn to be used for certain property names. The properties to + * which the extension will apply are opp-microvolt and opp-microamp. OPP core + * should postfix the property name with -<name> while looking for them. + * + * The opp_table structure will be freed after the device is destroyed. + */ +struct opp_table *devm_pm_opp_set_prop_name(struct device *dev, + const char *name) +{ + struct opp_table **ptr, *opp_table; + + ptr = devres_alloc(devm_pm_opp_put_prop_name, + sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return ERR_PTR(-ENOMEM); + + opp_table = dev_pm_opp_set_prop_name(dev, name); + if (!IS_ERR(opp_table)) { + *ptr = opp_table; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return opp_table; +} +EXPORT_SYMBOL(devm_pm_opp_set_prop_name); + static int _allocate_set_opp_data(struct opp_table *opp_table) { struct dev_pm_set_opp_data *data; diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h index 901920e29c54..1708485200dd 100644 --- a/include/linux/pm_opp.h +++ b/include/linux/pm_opp.h @@ -143,6 +143,7 @@ void dev_pm_opp_put_supported_hw(struct opp_table *opp_table); struct opp_table *devm_pm_opp_set_supported_hw(struct device *dev, const u32 *versions, unsigned int count); struct opp_table *dev_pm_opp_set_prop_name(struct device *dev, const char *name); void dev_pm_opp_put_prop_name(struct opp_table *opp_table); +struct opp_table *devm_pm_opp_set_prop_name(struct device *dev, const char *name); struct opp_table *dev_pm_opp_set_regulators(struct device *dev, const char * const names[], unsigned int count); void dev_pm_opp_put_regulators(struct opp_table *opp_table); struct opp_table *dev_pm_opp_set_clkname(struct device *dev, const char * name); @@ -321,6 +322,11 @@ static inline struct opp_table *dev_pm_opp_set_prop_name(struct device *dev, con static inline void dev_pm_opp_put_prop_name(struct opp_table *opp_table) {} +static inline struct opp_table *devm_pm_opp_set_prop_name(struct device *dev, const char *name) +{ + return ERR_PTR(-ENOTSUPP); +} + static inline struct opp_table *dev_pm_opp_set_regulators(struct device *dev, const char * const names[], unsigned int count) { return ERR_PTR(-ENOTSUPP);