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 <[email protected]>
---
See https://lore.kernel.org/lkml/[email protected]/
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
+ *
+ * @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
Hi Geert,
On Tue, 2018-11-13 at 13:47 +0100, Geert Uytterhoeven 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 <[email protected]>
Thank you, I have applied this patch to reset/next.
regards
Philipp
Thank you for your patch.
> On November 13, 2018 at 1:47 PM Geert Uytterhoeven <[email protected]> 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 <[email protected]>
> ---
> See https://lore.kernel.org/lkml/[email protected]/
> 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
On Wed, Nov 14, 2018 at 7:30 AM Ulrich Hecht <[email protected]> wrote:
> On November 13, 2018 at 1:47 PM Geert Uytterhoeven <[email protected]> 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 <[email protected]>
> > ---
> > See https://lore.kernel.org/lkml/[email protected]/
> > 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
> > +/**
> > + * of_reset_control_get_count - Count number of resets available with a device
>
> Should be "reset_control_get_count", without of_ prefix.
Oops, thanks for catching!
Philipp: Do you want a v2 or incremental, or can you fix it up yourself?
Thanks!
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
On Wed, 2018-11-14 at 09:58 +0100, Geert Uytterhoeven wrote:
> On Wed, Nov 14, 2018 at 7:30 AM Ulrich Hecht <[email protected]> wrote:
> > On November 13, 2018 at 1:47 PM Geert Uytterhoeven <[email protected]> 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 <[email protected]>
> > > ---
> > > See https://lore.kernel.org/lkml/[email protected]/
> > > 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
> > > +/**
> > > + * of_reset_control_get_count - Count number of resets available with a device
> >
> > Should be "reset_control_get_count", without of_ prefix.
>
> Oops, thanks for catching!
>
> Philipp: Do you want a v2 or incremental, or can you fix it up yourself?
No need, I'll fix it up.
thanks
Philipp
Hi Philipp,
On Wed, Nov 14, 2018 at 10:26 AM Philipp Zabel <[email protected]> wrote:
> On Wed, 2018-11-14 at 09:58 +0100, Geert Uytterhoeven wrote:
> > On Wed, Nov 14, 2018 at 7:30 AM Ulrich Hecht <[email protected]> wrote:
> > > On November 13, 2018 at 1:47 PM Geert Uytterhoeven <[email protected]> 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 <[email protected]>
> > > > --- a/drivers/reset/core.c
> > > > +++ b/drivers/reset/core.c
> > > > +/**
> > > > + * of_reset_control_get_count - Count number of resets available with a device
> > >
> > > Should be "reset_control_get_count", without of_ prefix.
> >
> > Oops, thanks for catching!
> >
> > Philipp: Do you want a v2 or incremental, or can you fix it up yourself?
>
> No need, I'll fix it up.
Thanks, and sorry for the typo.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds