diff mbox series

[v4,3/3] i2c: Extend i2c_device_get_match_data() to support i2c sysfs

Message ID 20230802112317.252745-4-biju.das.jz@bp.renesas.com
State New
Headers show
Series Extend device_get_match_data() to struct bus_type | expand

Commit Message

Biju Das Aug. 2, 2023, 11:23 a.m. UTC
Extend i2c_device_get_match_data() to i2c sysfs interface by changing
i2c_of_match_device_sysfs() to non-static and call this function as a
fallback for i2c_get_match_data_helper().

Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
---
v4:
 * split from patch #2
 * Added space after of_device_id for i2c_of_match_device_sysfs()
 * Added const parameter for struct i2c_client, to prevent overriding it's
   pointer.
 * Moved declaration from public i2c.h->i2c-core.h
---
 drivers/i2c/i2c-core-base.c | 16 +++++++++++++++-
 drivers/i2c/i2c-core-of.c   |  5 +++--
 drivers/i2c/i2c-core.h      |  9 +++++++++
 3 files changed, 27 insertions(+), 3 deletions(-)

Comments

Biju Das Aug. 3, 2023, 6:04 a.m. UTC | #1
Hi Andy Shevchenko,

Thanks for the feedback.

> Subject: Re: [PATCH v4 3/3] i2c: Extend i2c_device_get_match_data() to
> support i2c sysfs
> 
> On Wed, Aug 02, 2023 at 12:23:17PM +0100, Biju Das wrote:
> > Extend i2c_device_get_match_data() to i2c sysfs interface by changing
> > i2c_of_match_device_sysfs() to non-static and call this function as a
> > fallback for i2c_get_match_data_helper().
> 
> ...
> 
> >  	/* TODO: use i2c_verify_client() when it accepts const pointer */
> >  	const struct i2c_client *client = (dev->type ==
> &i2c_client_type) ?
> >  					  to_i2c_client(dev) : NULL;
> > +	const void *data;
> 
> Oh, yeah, definitely, please follow advice for previous patch I have
> given.

OK.

> 
> >  	if (!client || !dev->driver)
> >  		return NULL;
> >
> > -	return i2c_get_match_data_helper(client);
> > +	data = i2c_get_match_data_helper(client);
> > +	if (data)
> > +		return data;
> > +
> > +	if (dev->driver->of_match_table) {
> > +		const struct of_device_id *match;
> > +
> > +		match = i2c_of_match_device_sysfs(dev->driver-
> >of_match_table,
> > +						  client);
> 
> So, with this it makes sense to have
> 
> 	strucct device_driver *drv = dev->driver;
> 	...
> 	if (!drv)
> 		return NULL;
> 
> The above for the first patch even. And here

Agreed.

> 
> 		match = i2c_of_match_device_sysfs(drv->of_match_table,
> client);
> 
> > +		if (match)
> > +			return match->data;
> > +	}
> 
> > +	return data;
> 
> This actually should be
> 
> 	return NULL;
> 
> to avoid (potentially) stale pointers.

OK.

> 
> >  }
> 
> ...
> 
> > -static const struct of_device_id*
> > +const struct of_device_id *
> >  i2c_of_match_device_sysfs(const struct of_device_id *matches,
> > -				  struct i2c_client *client)
> > +			  const struct i2c_client *client)
> >  {
> >  	const char *name;
> >
> > @@ -141,6 +141,7 @@ i2c_of_match_device_sysfs(const struct
> > of_device_id *matches,
> >
> >  	return NULL;
> >  }
> > +EXPORT_SYMBOL_GPL(i2c_of_match_device_sysfs);
> >
> >  const struct of_device_id
> >  *i2c_of_match_device(const struct of_device_id *matches, diff --git
> > a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h index
> > 1247e6e6e975..e4d397b67989 100644
> > --- a/drivers/i2c/i2c-core.h
> > +++ b/drivers/i2c/i2c-core.h
> > @@ -82,8 +82,17 @@ static inline void
> > i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) {
> >
> >  #ifdef CONFIG_OF
> >  void of_i2c_register_devices(struct i2c_adapter *adap);
> > +const struct of_device_id *
> > +i2c_of_match_device_sysfs(const struct of_device_id *matches,
> > +			  const struct i2c_client *client);
> >  #else
> >  static inline void of_i2c_register_devices(struct i2c_adapter *adap)
> > { }
> > +static inline const struct of_device_id *
> > +i2c_of_match_device_sysfs(const struct of_device_id *matches,
> > +			  const struct i2c_client *client) {
> > +	return NULL;
> > +}
> >  #endif
> >  extern struct notifier_block i2c_of_notifier;
> 
> That's what above I meant to see as a separate change.

OK will create a separate patch for this change.

Cheers,
Biju
diff mbox series

Patch

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 2436f23e63af..d002c5a1cc84 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -131,11 +131,25 @@  static const void *i2c_device_get_match_data(const struct device *dev)
 	/* TODO: use i2c_verify_client() when it accepts const pointer */
 	const struct i2c_client *client = (dev->type == &i2c_client_type) ?
 					  to_i2c_client(dev) : NULL;
+	const void *data;
 
 	if (!client || !dev->driver)
 		return NULL;
 
-	return i2c_get_match_data_helper(client);
+	data = i2c_get_match_data_helper(client);
+	if (data)
+		return data;
+
+	if (dev->driver->of_match_table) {
+		const struct of_device_id *match;
+
+		match = i2c_of_match_device_sysfs(dev->driver->of_match_table,
+						  client);
+		if (match)
+			return match->data;
+	}
+
+	return data;
 }
 
 const void *i2c_get_match_data(const struct i2c_client *client)
diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c
index a6c407d36800..179b3486904a 100644
--- a/drivers/i2c/i2c-core-of.c
+++ b/drivers/i2c/i2c-core-of.c
@@ -113,9 +113,9 @@  void of_i2c_register_devices(struct i2c_adapter *adap)
 	of_node_put(bus);
 }
 
-static const struct of_device_id*
+const struct of_device_id *
 i2c_of_match_device_sysfs(const struct of_device_id *matches,
-				  struct i2c_client *client)
+			  const struct i2c_client *client)
 {
 	const char *name;
 
@@ -141,6 +141,7 @@  i2c_of_match_device_sysfs(const struct of_device_id *matches,
 
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(i2c_of_match_device_sysfs);
 
 const struct of_device_id
 *i2c_of_match_device(const struct of_device_id *matches,
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 1247e6e6e975..e4d397b67989 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -82,8 +82,17 @@  static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) {
 
 #ifdef CONFIG_OF
 void of_i2c_register_devices(struct i2c_adapter *adap);
+const struct of_device_id *
+i2c_of_match_device_sysfs(const struct of_device_id *matches,
+			  const struct i2c_client *client);
 #else
 static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
+static inline const struct of_device_id *
+i2c_of_match_device_sysfs(const struct of_device_id *matches,
+			  const struct i2c_client *client)
+{
+	return NULL;
+}
 #endif
 extern struct notifier_block i2c_of_notifier;