From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kiZix-0003Tk-BY for barebox@lists.infradead.org; Fri, 27 Nov 2020 09:07:28 +0000 Date: Fri, 27 Nov 2020 10:07:26 +0100 Message-ID: <20201127090726.GH11843@pengutronix.de> References: <20201124102430.17407-1-a.fatoum@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201124102430.17407-1-a.fatoum@pengutronix.de> From: Sascha Hauer List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v2 1/2] watchdog: implement watchdog_get_alias_id_from To: Ahmad Fatoum Cc: barebox@lists.infradead.org On Tue, Nov 24, 2020 at 11:24:29AM +0100, Ahmad Fatoum wrote: > On device-tree enabled platforms, the Linux kernel will first attempt > to use watchdog%d as watchdog name, where %d is the alias id. > > Add a function that given a barebox struct watchdog and the device tree > root node of the kernel device tree, computes the corresponding kernel > alias id. > > This may then later be used to pass an appropriate argument on the > kernel command line. > > Signed-off-by: Ahmad Fatoum > --- > v1 -> v2: > - removed extern where unneeded (Sascha) > --- > drivers/of/base.c | 77 ++++++++++++++++++++++++++++++-------- > drivers/watchdog/wd_core.c | 19 ++++++++++ > include/of.h | 8 ++++ > include/watchdog.h | 8 ++++ > 4 files changed, 97 insertions(+), 15 deletions(-) Applied, thanks Sascha > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 5b45c2023f3b..acbae3d8c4bb 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -149,6 +149,31 @@ static void of_alias_add(struct alias_prop *ap, struct device_node *np, > ap->alias, ap->stem, ap->id, np->full_name); > } > > +static struct device_node *of_alias_resolve(struct device_node *root, struct property *pp) > +{ > + /* Skip those we do not want to proceed */ > + if (!of_prop_cmp(pp->name, "name") || > + !of_prop_cmp(pp->name, "phandle") || > + !of_prop_cmp(pp->name, "linux,phandle")) > + return NULL; > + > + return of_find_node_by_path_from(root, of_property_get_value(pp)); > +} > + > +static int of_alias_id_parse(const char *start, int *len) > +{ > + const char *end = start + strlen(start); > + > + /* walk the alias backwards to extract the id and work out > + * the 'stem' string */ > + while (isdigit(*(end-1)) && end > start) > + end--; > + > + *len = end - start; > + > + return simple_strtol(end, NULL, 10); > +} > + > /** > * of_alias_scan - Scan all properties of 'aliases' node > * > @@ -175,28 +200,15 @@ void of_alias_scan(void) > > list_for_each_entry(pp, &of_aliases->properties, list) { > const char *start = pp->name; > - const char *end = start + strlen(start); > struct device_node *np; > struct alias_prop *ap; > int id, len; > > - /* Skip those we do not want to proceed */ > - if (!of_prop_cmp(pp->name, "name") || > - !of_prop_cmp(pp->name, "phandle") || > - !of_prop_cmp(pp->name, "linux,phandle")) > - continue; > - > - np = of_find_node_by_path(of_property_get_value(pp)); > + np = of_alias_resolve(root_node, pp); > if (!np) > continue; > > - /* walk the alias backwards to extract the id and work out > - * the 'stem' string */ > - while (isdigit(*(end-1)) && end > start) > - end--; > - len = end - start; > - > - id = simple_strtol(end, NULL, 10); > + id = of_alias_id_parse(start, &len); > if (id < 0) > continue; > > @@ -235,6 +247,41 @@ int of_alias_get_id(struct device_node *np, const char *stem) > } > EXPORT_SYMBOL_GPL(of_alias_get_id); > > +int of_alias_get_id_from(struct device_node *root, struct device_node *np, > + const char *stem) > +{ > + struct device_node *aliasnp, *entrynp; > + struct property *pp; > + > + if (!root) > + return of_alias_get_id(np, stem); > + > + aliasnp = of_find_node_by_path_from(root, "/aliases"); > + if (!aliasnp) > + return -ENODEV; > + > + for_each_property_of_node(aliasnp, pp) { > + const char *start = pp->name; > + int id, len; > + > + entrynp = of_alias_resolve(root_node, pp); > + if (entrynp != np) > + continue; > + > + id = of_alias_id_parse(start, &len); > + if (id < 0) > + continue; > + > + if (strncasecmp(start, stem, len)) > + continue; > + > + return id; > + } > + > + return -ENODEV; > +} > +EXPORT_SYMBOL_GPL(of_alias_get_id_from); > + > const char *of_alias_get(struct device_node *np) > { > struct alias_prop *app; > diff --git a/drivers/watchdog/wd_core.c b/drivers/watchdog/wd_core.c > index 665338af6197..643c53268fc8 100644 > --- a/drivers/watchdog/wd_core.c > +++ b/drivers/watchdog/wd_core.c > @@ -261,6 +261,25 @@ struct watchdog *watchdog_get_default(void) > } > EXPORT_SYMBOL(watchdog_get_default); > > +int watchdog_get_alias_id_from(struct watchdog *wd, struct device_node *root) > +{ > + struct device_node *dstnp, *srcnp = wd->hwdev ? wd->hwdev->device_node : NULL; > + char *name; > + > + if (!srcnp) > + return -ENODEV; > + > + name = of_get_reproducible_name(srcnp); > + dstnp = of_find_node_by_reproducible_name(root, name); > + free(name); > + > + if (!dstnp) > + return -ENODEV; > + > + return of_alias_get_id_from(root, wd->hwdev->device_node, "watchdog"); > +} > +EXPORT_SYMBOL(watchdog_get_alias_id_from); > + > struct watchdog *watchdog_get_by_name(const char *name) > { > struct watchdog *tmp; > diff --git a/include/of.h b/include/of.h > index 08a02e110522..dc3aa0730bf7 100644 > --- a/include/of.h > +++ b/include/of.h > @@ -254,6 +254,8 @@ extern int of_count_phandle_with_args(const struct device_node *np, > > extern void of_alias_scan(void); > extern int of_alias_get_id(struct device_node *np, const char *stem); > +extern int of_alias_get_id_from(struct device_node *root, struct device_node *np, > + const char *stem); > extern const char *of_alias_get(struct device_node *np); > extern int of_modalias_node(struct device_node *node, char *modalias, int len); > > @@ -677,6 +679,12 @@ static inline int of_alias_get_id(struct device_node *np, const char *stem) > return -ENOSYS; > } > > +static inline int of_alias_get_id_from(struct device_node *root, struct device_node *np, > + const char *stem) > +{ > + return -ENOSYS > +} > + > static inline const char *of_alias_get(struct device_node *np) > { > return NULL; > diff --git a/include/watchdog.h b/include/watchdog.h > index 81414ef8ecaa..ee8efdecd030 100644 > --- a/include/watchdog.h > +++ b/include/watchdog.h > @@ -13,6 +13,8 @@ enum wdog_hw_runnning { > WDOG_HW_NOT_RUNNING = PARAM_TRISTATE_FALSE > }; > > +struct device_node; > + > struct watchdog { > int (*set_timeout)(struct watchdog *, unsigned); > const char *name; > @@ -44,6 +46,7 @@ int watchdog_register(struct watchdog *); > int watchdog_deregister(struct watchdog *); > struct watchdog *watchdog_get_default(void); > struct watchdog *watchdog_get_by_name(const char *name); > +int watchdog_get_alias_id_from(struct watchdog *, struct device_node *); > int watchdog_set_timeout(struct watchdog*, unsigned); > int watchdog_inhibit_all(void); > #else > @@ -76,6 +79,11 @@ static inline int watchdog_inhibit_all(void) > { > return -ENOSYS; > } > + > +static inline int watchdog_get_alias_id_from(struct watchdog *, struct device_node *) > +{ > + return -ENOSYS; > +} > #endif > > #define WATCHDOG_DEFAULT_PRIORITY 100 > -- > 2.29.2 > > > _______________________________________________ > barebox mailing list > barebox@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/barebox > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox