[PATCH v1 0/6] i2c: core: Move client towards fwnode

[PATCH v1 0/6] 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 was sent today. Nevertheless
the series moves the client handling code to use fwnode and deprecates
the of_node member in the respective documentation.

Andy Shevchenko (6):
  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

 drivers/i2c/i2c-core-base.c | 58 ++++++++++++++++++-------------------
 include/linux/i2c.h         |  2 +-
 2 files changed, 30 insertions(+), 30 deletions(-)

-- 
2.47.2

[PATCH v1 1/6] i2c: core: Drop duplicate check before calling OF APIs

[Andy Shevchenko]

OF APIs are usually NULL-aware and returns 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.

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 v1 2/6] 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.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index c14ffd6190d3..edab56e5d5e5 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);
@@ -1054,15 +1055,16 @@ 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);
-- 
2.47.2

Re: [PATCH v1 2/6] i2c: core: Unify the firmware node type check

[Andy Shevchenko]

On Wed, Mar 12, 2025 at 08:48:49PM +0200, Andy Shevchenko wrote:
> 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.

>  drivers/i2c/i2c-core-base.c | 14 ++++++++------

The i2c-core-slave.c can be also modified to follow the same approach.
I'll do that way in v2.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v1 3/6] 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. The rest is converted
just for the sake of consistency and fwnode reuse.

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 edab56e5d5e5..f0420cc0df26 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -510,9 +510,9 @@ 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 +547,7 @@ 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 v1 4/6] 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.

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 f0420cc0df26..1236061a78c3 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -568,7 +568,7 @@ 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;
 
@@ -1062,10 +1062,10 @@ 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);
 	device_unregister(&client->dev);
-- 
2.47.2

[PATCH v1 5/6] 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.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 drivers/i2c/i2c-core-base.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 1236061a78c3..dba6c5ce9d42 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -962,6 +962,7 @@ 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;
@@ -1002,18 +1003,19 @@ 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;
 		}
 	}
 
@@ -1032,8 +1034,8 @@ 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",
@@ -1061,11 +1063,11 @@ 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);
-- 
2.47.2

Re: [PATCH v1 5/6] i2c: core: Do not dereference fwnode in struct device

[Andy Shevchenko]

On Wed, Mar 12, 2025 at 08:48:52PM +0200, Andy Shevchenko wrote:
> 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.

>  drivers/i2c/i2c-core-base.c | 18 ++++++++++--------

This missed i2c-core-of.c changes.

-- 
With Best Regards,
Andy Shevchenko

[PATCH v1 6/6] i2c: core: Deprecate of_node in struct i2c_board_info

[Andy Shevchenko]

Two members of the same or similar semantics is quite confusing to begin with.
Moreover, the 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 remote it completely.

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