[PATCH v5 0/7] i2c: core: Move client towards fwnode

[PATCH v5 0/7] i2c: core: Move client towards fwnode

[Andy Shevchenko]

The struct i2c_board_info has of_node and fwnode members. This is quite
confusing as they are of the same semantics and it's tend to have an issue
if user assigns both. Luckily there is only a single driver that does this
and fix is provided in the last patch. Nevertheless the series moves
the client handling code to use fwnode and deprecates the of_node member
in the respective documentation.

In v5:
- reformatted conditionals to make media CI happy (media CI)
- updated commit messages in patches 3 & 6 to make it more clear (Wolfram)

In v4:
- fixed spelling in the first patch commit message (Sakari)
- wrapped the commit message in the patch before the last (Sakari)
- added tag to the last patch (Tomi)

In v3:
- fixed compile issues with i2c-core-slave.c (LKP)
- fixed compile issues with IRQ APIs, i.e. missing header (LKP)
- added patch for the only user which assigns two fields (Tomi)
- added tags (Tomi)

In v2:
- covered i2c-core-slave.c where it makes sense
- covered i2c-core-of.c where it makes sense
- rebased on top of the latest code base

Andy Shevchenko (7):
  i2c: core: Drop duplicate check before calling OF APIs
  i2c: core: Unify the firmware node type check
  i2c: core: Switch to fwnode APIs to get IRQ
  i2c: core: Reuse fwnode variable where it makes sense
  i2c: core: Do not dereference fwnode in struct device
  i2c: core: Deprecate of_node in struct i2c_board_info
  media: i2c: ds90ub960: Remove of_node assignment

 drivers/i2c/i2c-core-base.c   | 61 +++++++++++++++++------------------
 drivers/i2c/i2c-core-of.c     |  1 -
 drivers/i2c/i2c-core-slave.c  | 12 ++++---
 drivers/media/i2c/ds90ub960.c |  1 -
 include/linux/i2c.h           |  2 +-
 5 files changed, 39 insertions(+), 38 deletions(-)

-- 
2.47.2

[PATCH v5 1/7] i2c: core: Drop duplicate check before calling OF APIs

[Andy Shevchenko]

OF APIs are usually NULL-aware and return an error in case when
device node is not present or supported. We already have a check
for the returned value, no need to check for the parameter.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 7ad1ad5c8c3f..c14ffd6190d3 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -1209,11 +1209,9 @@ struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client,
 	u32 addr = default_addr;
 	int i;
 
-	if (np) {
-		i = of_property_match_string(np, "reg-names", name);
-		if (i >= 0)
-			of_property_read_u32_index(np, "reg", i, &addr);
-	}
+	i = of_property_match_string(np, "reg-names", name);
+	if (i >= 0)
+		of_property_read_u32_index(np, "reg", i, &addr);
 
 	dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr);
 	return i2c_new_dummy_device(client->adapter, addr);
@@ -1651,12 +1649,10 @@ int i2c_add_adapter(struct i2c_adapter *adapter)
 	struct device *dev = &adapter->dev;
 	int id;
 
-	if (dev->of_node) {
-		id = of_alias_get_id(dev->of_node, "i2c");
-		if (id >= 0) {
-			adapter->nr = id;
-			return __i2c_add_numbered_adapter(adapter);
-		}
+	id = of_alias_get_id(dev->of_node, "i2c");
+	if (id >= 0) {
+		adapter->nr = id;
+		return __i2c_add_numbered_adapter(adapter);
 	}
 
 	mutex_lock(&core_lock);
-- 
2.47.2

[PATCH v5 2/7] i2c: core: Unify the firmware node type check

[Andy Shevchenko]

OF and ACPI currently are using asymmetrical APIs to check
for the firmware node type. Unify them by using is_*_node()
against struct fwnode_handle pointer.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c  | 15 +++++++++------
 drivers/i2c/i2c-core-slave.c | 12 ++++++++----
 2 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index c14ffd6190d3..2b5236b726af 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -490,6 +490,7 @@ static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client)
 
 static int i2c_device_probe(struct device *dev)
 {
+	struct fwnode_handle	*fwnode = dev_fwnode(dev);
 	struct i2c_client	*client = i2c_verify_client(dev);
 	struct i2c_driver	*driver;
 	bool do_power_on;
@@ -508,11 +509,11 @@ static int i2c_device_probe(struct device *dev)
 			/* Keep adapter active when Host Notify is required */
 			pm_runtime_get_sync(&client->adapter->dev);
 			irq = i2c_smbus_host_notify_to_irq(client);
-		} else if (dev->of_node) {
+		} else if (is_of_node(fwnode)) {
 			irq = of_irq_get_byname(dev->of_node, "irq");
 			if (irq == -EINVAL || irq == -ENODATA)
 				irq = of_irq_get(dev->of_node, 0);
-		} else if (ACPI_COMPANION(dev)) {
+		} else if (is_acpi_device_node(fwnode)) {
 			bool wake_capable;
 
 			irq = i2c_acpi_get_irq(client, &wake_capable);
@@ -1054,16 +1055,18 @@ EXPORT_SYMBOL_GPL(i2c_new_client_device);
  */
 void i2c_unregister_device(struct i2c_client *client)
 {
+	struct fwnode_handle *fwnode;
+
 	if (IS_ERR_OR_NULL(client))
 		return;
 
-	if (client->dev.of_node) {
+	fwnode = dev_fwnode(&client->dev);
+	if (is_of_node(fwnode)) {
 		of_node_clear_flag(client->dev.of_node, OF_POPULATED);
 		of_node_put(client->dev.of_node);
-	}
-
-	if (ACPI_COMPANION(&client->dev))
+	} else if (is_acpi_device_node(fwnode)) {
 		acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev));
+	}
 
 	device_remove_software_node(&client->dev);
 	device_unregister(&client->dev);
diff --git a/drivers/i2c/i2c-core-slave.c b/drivers/i2c/i2c-core-slave.c
index faefe1dfa8e5..7ee6b992b835 100644
--- a/drivers/i2c/i2c-core-slave.c
+++ b/drivers/i2c/i2c-core-slave.c
@@ -11,6 +11,7 @@
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/of.h>
+#include <linux/property.h>
 
 #include "i2c-core.h"
 
@@ -108,15 +109,18 @@ EXPORT_SYMBOL_GPL(i2c_slave_event);
  */
 bool i2c_detect_slave_mode(struct device *dev)
 {
-	if (IS_BUILTIN(CONFIG_OF) && dev->of_node) {
+	struct fwnode_handle *fwnode = dev_fwnode(dev);
+
+	if (is_of_node(fwnode)) {
+		struct fwnode_handle *child __free(fwnode_handle) = NULL;
 		u32 reg;
 
-		for_each_child_of_node_scoped(dev->of_node, child) {
-			of_property_read_u32(child, "reg", &reg);
+		fwnode_for_each_child_node(fwnode, child) {
+			fwnode_property_read_u32(child, "reg", &reg);
 			if (reg & I2C_OWN_SLAVE_ADDRESS)
 				return true;
 		}
-	} else if (IS_BUILTIN(CONFIG_ACPI) && ACPI_HANDLE(dev)) {
+	} else if (is_acpi_device_node(fwnode)) {
 		dev_dbg(dev, "ACPI slave is not supported yet\n");
 	}
 	return false;
-- 
2.47.2

[PATCH v5 3/7] i2c: core: Switch to fwnode APIs to get IRQ

[Andy Shevchenko]

Switch to fwnode APIs to get IRQ. In particular this enables
a support of the separate wakeup IRQ on non-OF platforms.
The rest is converted just for the sake of consistency and
fwnode reuse.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 2b5236b726af..08ff3f1eb28e 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -26,14 +26,13 @@
 #include <linux/idr.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
-#include <linux/irqflags.h>
+#include <linux/irq.h>
 #include <linux/jump_label.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/of_device.h>
 #include <linux/of.h>
-#include <linux/of_irq.h>
 #include <linux/pinctrl/consumer.h>
 #include <linux/pinctrl/devinfo.h>
 #include <linux/pm_domain.h>
@@ -510,9 +509,9 @@ static int i2c_device_probe(struct device *dev)
 			pm_runtime_get_sync(&client->adapter->dev);
 			irq = i2c_smbus_host_notify_to_irq(client);
 		} else if (is_of_node(fwnode)) {
-			irq = of_irq_get_byname(dev->of_node, "irq");
+			irq = fwnode_irq_get_byname(fwnode, "irq");
 			if (irq == -EINVAL || irq == -ENODATA)
-				irq = of_irq_get(dev->of_node, 0);
+				irq = fwnode_irq_get(fwnode, 0);
 		} else if (is_acpi_device_node(fwnode)) {
 			bool wake_capable;
 
@@ -547,7 +546,7 @@ static int i2c_device_probe(struct device *dev)
 	if (client->flags & I2C_CLIENT_WAKE) {
 		int wakeirq;
 
-		wakeirq = of_irq_get_byname(dev->of_node, "wakeup");
+		wakeirq = fwnode_irq_get_byname(fwnode, "wakeup");
 		if (wakeirq == -EPROBE_DEFER) {
 			status = wakeirq;
 			goto put_sync_adapter;
-- 
2.47.2

[PATCH v5 4/7] i2c: core: Reuse fwnode variable where it makes sense

[Andy Shevchenko]

Reuse fwnode variable where it makes sense. This avoids unneeded
duplication hidden in some macros and unifies the code for different
types of fwnode.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 08ff3f1eb28e..b186de31a9ee 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -567,7 +567,7 @@ static int i2c_device_probe(struct device *dev)
 
 	dev_dbg(dev, "probe\n");
 
-	status = of_clk_set_defaults(dev->of_node, false);
+	status = of_clk_set_defaults(to_of_node(fwnode), false);
 	if (status < 0)
 		goto err_clear_wakeup_irq;
 
@@ -1061,10 +1061,10 @@ void i2c_unregister_device(struct i2c_client *client)
 
 	fwnode = dev_fwnode(&client->dev);
 	if (is_of_node(fwnode)) {
-		of_node_clear_flag(client->dev.of_node, OF_POPULATED);
+		of_node_clear_flag(to_of_node(fwnode), OF_POPULATED);
 		of_node_put(client->dev.of_node);
 	} else if (is_acpi_device_node(fwnode)) {
-		acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev));
+		acpi_device_clear_enumerated(to_acpi_device_node(fwnode));
 	}
 
 	device_remove_software_node(&client->dev);
-- 
2.47.2

[PATCH v5 5/7] i2c: core: Do not dereference fwnode in struct device

[Andy Shevchenko]

In order to make the underneath API easier to change in the future,
prevent users from dereferencing fwnode from struct device.
Instead, use the specific device_set_node() API for that.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 19 ++++++++++---------
 drivers/i2c/i2c-core-of.c   |  1 -
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index b186de31a9ee..dc3c60a7d382 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -961,6 +961,7 @@ static void i2c_unlock_addr(struct i2c_adapter *adap, unsigned short addr,
 struct i2c_client *
 i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
 {
+	struct fwnode_handle *fwnode;
 	struct i2c_client *client;
 	bool need_put = false;
 	int status;
@@ -1001,18 +1002,19 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf
 	client->dev.parent = &client->adapter->dev;
 	client->dev.bus = &i2c_bus_type;
 	client->dev.type = &i2c_client_type;
-	client->dev.of_node = of_node_get(info->of_node);
-	client->dev.fwnode = info->fwnode;
 
 	device_enable_async_suspend(&client->dev);
 
+	fwnode = info->fwnode ?: of_fwnode_handle(info->of_node);
+	device_set_node(&client->dev, fwnode_handle_get(fwnode));
+
 	if (info->swnode) {
 		status = device_add_software_node(&client->dev, info->swnode);
 		if (status) {
 			dev_err(&adap->dev,
 				"Failed to add software node to client %s: %d\n",
 				client->name, status);
-			goto out_err_put_of_node;
+			goto out_err_put_fwnode;
 		}
 	}
 
@@ -1031,8 +1033,8 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf
 out_remove_swnode:
 	device_remove_software_node(&client->dev);
 	need_put = true;
-out_err_put_of_node:
-	of_node_put(info->of_node);
+out_err_put_fwnode:
+	fwnode_handle_put(fwnode);
 out_err:
 	dev_err(&adap->dev,
 		"Failed to register i2c client %s at 0x%02x (%d)\n",
@@ -1060,12 +1062,11 @@ void i2c_unregister_device(struct i2c_client *client)
 		return;
 
 	fwnode = dev_fwnode(&client->dev);
-	if (is_of_node(fwnode)) {
+	if (is_of_node(fwnode))
 		of_node_clear_flag(to_of_node(fwnode), OF_POPULATED);
-		of_node_put(client->dev.of_node);
-	} else if (is_acpi_device_node(fwnode)) {
+	else if (is_acpi_device_node(fwnode))
 		acpi_device_clear_enumerated(to_acpi_device_node(fwnode));
-	}
+	fwnode_handle_put(fwnode);
 
 	device_remove_software_node(&client->dev);
 	device_unregister(&client->dev);
diff --git a/drivers/i2c/i2c-core-of.c b/drivers/i2c/i2c-core-of.c
index 02feee6c9ba9..eb7fb202355f 100644
--- a/drivers/i2c/i2c-core-of.c
+++ b/drivers/i2c/i2c-core-of.c
@@ -49,7 +49,6 @@ int of_i2c_get_board_info(struct device *dev, struct device_node *node,
 	}
 
 	info->addr = addr;
-	info->of_node = node;
 	info->fwnode = of_fwnode_handle(node);
 
 	if (of_property_read_bool(node, "host-notify"))
-- 
2.47.2

[PATCH v5 6/7] i2c: core: Deprecate of_node in struct i2c_board_info

[Andy Shevchenko]

Two members of the same or quite similar semantics is quite confusing
to begin with. Moreover, fwnode covers all possible firmware descriptions
that Linux kernel supports. Deprecate of_node in struct i2c_board_info,
so users will be warned and in the future there is a plan to convert
the users and remove it completely.

Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 include/linux/i2c.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 2e4903b7f7bc..cc1437f29823 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -405,7 +405,7 @@ static inline bool i2c_detect_slave_mode(struct device *dev) { return false; }
  * @addr: stored in i2c_client.addr
  * @dev_name: Overrides the default <busnr>-<addr> dev_name if set
  * @platform_data: stored in i2c_client.dev.platform_data
- * @of_node: pointer to OpenFirmware device node
+ * @of_node: **DEPRECATED** - use @fwnode for this
  * @fwnode: device node supplied by the platform firmware
  * @swnode: software node for the device
  * @resources: resources associated with the device
-- 
2.47.2

[PATCH v5 7/7] media: i2c: ds90ub960: Remove of_node assignment

[Andy Shevchenko]

Remove of_node assignment which duplicates fwnode in struct i2c_board_info.
In general drivers must not set both, it's quite confusing. The I²C core
will consider fwnode with a priority and of_node is subject to remove from
above mentioned data structure.

Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
---
 drivers/media/i2c/ds90ub960.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c
index 5dde8452739b..5afdbbad9ff4 100644
--- a/drivers/media/i2c/ds90ub960.c
+++ b/drivers/media/i2c/ds90ub960.c
@@ -1682,7 +1682,6 @@ static int ub960_rxport_add_serializer(struct ub960_data *priv, u8 nport)
 	struct device *dev = &priv->client->dev;
 	struct ds90ub9xx_platform_data *ser_pdata = &rxport->ser.pdata;
 	struct i2c_board_info ser_info = {
-		.of_node = to_of_node(rxport->ser.fwnode),
 		.fwnode = rxport->ser.fwnode,
 		.platform_data = ser_pdata,
 	};
-- 
2.47.2

Re: [PATCH v5 0/7] i2c: core: Move client towards fwnode

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 1719 bytes --]

On Wed, Apr 16, 2025 at 10:01:30AM +0300, Andy Shevchenko wrote:
> The struct i2c_board_info has of_node and fwnode members. This is quite
> confusing as they are of the same semantics and it's tend to have an issue
> if user assigns both. Luckily there is only a single driver that does this
> and fix is provided in the last patch. Nevertheless the series moves
> the client handling code to use fwnode and deprecates the of_node member
> in the respective documentation.
> 
> In v5:
> - reformatted conditionals to make media CI happy (media CI)
> - updated commit messages in patches 3 & 6 to make it more clear (Wolfram)
> 
> In v4:
> - fixed spelling in the first patch commit message (Sakari)
> - wrapped the commit message in the patch before the last (Sakari)
> - added tag to the last patch (Tomi)
> 
> In v3:
> - fixed compile issues with i2c-core-slave.c (LKP)
> - fixed compile issues with IRQ APIs, i.e. missing header (LKP)
> - added patch for the only user which assigns two fields (Tomi)
> - added tags (Tomi)
> 
> In v2:
> - covered i2c-core-slave.c where it makes sense
> - covered i2c-core-of.c where it makes sense
> - rebased on top of the latest code base
> 
> Andy Shevchenko (7):
>   i2c: core: Drop duplicate check before calling OF APIs
>   i2c: core: Unify the firmware node type check
>   i2c: core: Switch to fwnode APIs to get IRQ
>   i2c: core: Reuse fwnode variable where it makes sense
>   i2c: core: Do not dereference fwnode in struct device
>   i2c: core: Deprecate of_node in struct i2c_board_info
>   media: i2c: ds90ub960: Remove of_node assignment
> 

Works at least on my OF-based platform. Let's go CI.

Applied to for-next, thanks!


[-- Attachment #2: signature.asc --]
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Re: [PATCH v5 0/7] i2c: core: Move client towards fwnode

[Andy Shevchenko]

On Wed, Apr 16, 2025 at 06:11:02PM +0200, Wolfram Sang wrote:
> On Wed, Apr 16, 2025 at 10:01:30AM +0300, Andy Shevchenko wrote:
> > The struct i2c_board_info has of_node and fwnode members. This is quite
> > confusing as they are of the same semantics and it's tend to have an issue
> > if user assigns both. Luckily there is only a single driver that does this
> > and fix is provided in the last patch. Nevertheless the series moves
> > the client handling code to use fwnode and deprecates the of_node member
> > in the respective documentation.

...

> Works at least on my OF-based platform. Let's go CI.
> 
> Applied to for-next, thanks!
Thank you!

-- 
With Best Regards,
Andy Shevchenko