Thank you for your patch. > On November 13, 2018 at 1:47 PM Geert Uytterhoeven <geert+renesas@xxxxxxxxx> wrote: > > > Currently the reset core has internal support for counting the number of > resets for a device described in DT. Generalize this to devices using > lookup resets, and export it for public use. > > This will be used by generic drivers that need to be sure a device is > controlled by a single, dedicated reset line (e.g. vfio-platform). > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> > --- > See https://lore.kernel.org/lkml/1539003437.11512.20.camel@xxxxxxxxxxxxxx/ > for the rationale to ensure a single, dedicated reset line. > > drivers/reset/core.c | 41 +++++++++++++++++++++++++++++++++++++++++ > include/linux/reset.h | 7 +++++++ > 2 files changed, 48 insertions(+) > > diff --git a/drivers/reset/core.c b/drivers/reset/core.c > index 654e20ff2d5da9d4..c32b755ec373c338 100644 > --- a/drivers/reset/core.c > +++ b/drivers/reset/core.c > @@ -859,3 +859,44 @@ devm_reset_control_array_get(struct device *dev, bool shared, bool optional) > return rstc; > } > EXPORT_SYMBOL_GPL(devm_reset_control_array_get); > + > +static int reset_control_get_count_from_lookup(struct device *dev) > +{ > + const struct reset_control_lookup *lookup; > + const char *dev_id = dev_name(dev); > + int count = 0; > + > + if (!dev) > + return -EINVAL; > + > + mutex_lock(&reset_lookup_mutex); > + > + list_for_each_entry(lookup, &reset_lookup_list, list) { > + if (!strcmp(lookup->dev_id, dev_id)) > + count++; > + } > + > + mutex_unlock(&reset_lookup_mutex); > + > + if (count == 0) > + count = -ENOENT; > + > + return count; > +} > + > +/** > + * of_reset_control_get_count - Count number of resets available with a device Should be "reset_control_get_count", without of_ prefix. > + * > + * @dev: device for which to return the number of resets > + * > + * Returns positive reset count on success, or error number on failure and > + * on count being zero. > + */ > +int reset_control_get_count(struct device *dev) > +{ > + if (dev->of_node) > + return of_reset_control_get_count(dev->of_node); > + > + return reset_control_get_count_from_lookup(dev); > +} > +EXPORT_SYMBOL_GPL(reset_control_get_count); > diff --git a/include/linux/reset.h b/include/linux/reset.h > index f0b094130686bf32..2698b36bd1eb3e0c 100644 > --- a/include/linux/reset.h > +++ b/include/linux/reset.h > @@ -32,6 +32,8 @@ struct reset_control *devm_reset_control_array_get(struct device *dev, > struct reset_control *of_reset_control_array_get(struct device_node *np, > bool shared, bool optional); > > +int reset_control_get_count(struct device *dev); > + > #else > > static inline int reset_control_reset(struct reset_control *rstc) > @@ -97,6 +99,11 @@ of_reset_control_array_get(struct device_node *np, bool shared, bool optional) > return optional ? NULL : ERR_PTR(-ENOTSUPP); > } > > +static inline int reset_control_get_count(struct device *dev) > +{ > + return -ENOENT; > +} > + > #endif /* CONFIG_RESET_CONTROLLER */ > > static inline int __must_check device_reset(struct device *dev) > -- > 2.17.1 > CU Uli
