[v2,02/22] i2c: acpi: Modify i2c_acpi_get_irq() to use resource

Commit Message

Mark Hasemeyer Dec. 20, 2023, 11:54 p.m. UTC

The i2c_acpi_irq_context structure provides redundant information that
can be provided with struct resource.

Refactor i2c_acpi_get_irq() to use struct resource instead of struct
i2c_acpi_irq_context.

Signed-off-by: Mark Hasemeyer <[e-mail]>
---

Changes in v2:
-New patch

 drivers/i2c/i2c-core-acpi.c | 44 ++++++++++++++-----------------------
 drivers/i2c/i2c-core-base.c |  6 ++---
 drivers/i2c/i2c-core.h      |  4 ++--
 3 files changed, 22 insertions(+), 32 deletions(-)

Comments

Andy Shevchenko Dec. 21, 2023, 1:51 p.m. UTC | #1

On Wed, Dec 20, 2023 at 04:54:16PM -0700, Mark Hasemeyer wrote:
> The i2c_acpi_irq_context structure provides redundant information that
> can be provided with struct resource.
> 
> Refactor i2c_acpi_get_irq() to use struct resource instead of struct
> i2c_acpi_irq_context.

Suggested-by?

...

>  static int i2c_acpi_add_irq_resource(struct acpi_resource *ares, void *data)
>  {
> -	struct i2c_acpi_irq_context *irq_ctx = data;
> -	struct resource r;
> +	struct resource *r = data;

> -	if (irq_ctx->irq > 0)
> +	if (r->start > 0)
>  		return 1;

Checking flags is more robust.

	if (r->flags)
		return 1;

> -	if (!acpi_dev_resource_interrupt(ares, 0, &r))
> +	if (!acpi_dev_resource_interrupt(ares, 0, r))
>  		return 1;
>  
> -	irq_ctx->irq = i2c_dev_irq_from_resources(&r, 1);
> -	irq_ctx->wake_capable = r.flags & IORESOURCE_IRQ_WAKECAPABLE;
> +	i2c_dev_irq_from_resources(r, 1);
>  
>  	return 1; /* No need to add resource to the list */
>  }

...

> +	if (IS_ERR_OR_NULL(r))
> +		return -EINVAL;

Hmm... Do we expect this to be an error pointer in some cases?

...

> +	ret = acpi_dev_get_gpio_irq_resource(adev, NULL, 0, r);
> +	if (!ret)
> +		return r->start;
>  
> -	return irq_ctx.irq;
> +	return ret;

What's wrong with the standard pattern?

	if (ret)
		return ret;
	...
	return ...;

...

> +			struct resource r = {0};

'0' is redundant.

...

> +			irq = i2c_acpi_get_irq(client, &r);
> +			if (irq > 0 && r.flags & IORESOURCE_IRQ_WAKECAPABLE)

Why checking just flags is not enough?

>  				client->flags |= I2C_CLIENT_WAKE;

Patch

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 8126a87baf3d4..01cf140da21af 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -175,64 +175,54 @@  static int i2c_acpi_do_lookup(struct acpi_device *adev,
 
 static int i2c_acpi_add_irq_resource(struct acpi_resource *ares, void *data)
 {
-	struct i2c_acpi_irq_context *irq_ctx = data;
-	struct resource r;
+	struct resource *r = data;
 
-	if (irq_ctx->irq > 0)
+	if (r->start > 0)
 		return 1;
 
-	if (!acpi_dev_resource_interrupt(ares, 0, &r))
+	if (!acpi_dev_resource_interrupt(ares, 0, r))
 		return 1;
 
-	irq_ctx->irq = i2c_dev_irq_from_resources(&r, 1);
-	irq_ctx->wake_capable = r.flags & IORESOURCE_IRQ_WAKECAPABLE;
+	i2c_dev_irq_from_resources(r, 1);
 
 	return 1; /* No need to add resource to the list */
 }
 
 /**
- * i2c_acpi_get_irq - get device IRQ number from ACPI
+ * i2c_acpi_get_irq - get device IRQ number from ACPI and populate resource
  * @client: Pointer to the I2C client device
- * @wake_capable: Set to true if the IRQ is wake capable
+ * @r: resource with populated IRQ information
  *
  * Find the IRQ number used by a specific client device.
  *
  * Return: The IRQ number or an error code.
  */
-int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
+int i2c_acpi_get_irq(struct i2c_client *client, struct resource *r)
 {
 	struct acpi_device *adev = ACPI_COMPANION(&client->dev);
 	struct list_head resource_list;
-	struct resource irqres;
-	struct i2c_acpi_irq_context irq_ctx = {
-		.irq = -ENOENT,
-	};
 	int ret;
 
+	if (IS_ERR_OR_NULL(r))
+		return -EINVAL;
+
 	INIT_LIST_HEAD(&resource_list);
 
 	ret = acpi_dev_get_resources(adev, &resource_list,
-				     i2c_acpi_add_irq_resource, &irq_ctx);
+				     i2c_acpi_add_irq_resource, r);
 	if (ret < 0)
 		return ret;
 
 	acpi_dev_free_resource_list(&resource_list);
 
-	if (irq_ctx.irq == -ENOENT) {
-		ret = acpi_dev_get_gpio_irq_resource(adev, NULL, 0, &irqres);
-		if (ret)
-			return ret;
-		irq_ctx.irq = irqres.start;
-		irq_ctx.wake_capable = irqres.flags & IORESOURCE_IRQ_WAKECAPABLE;
-	}
-
-	if (irq_ctx.irq < 0)
-		return irq_ctx.irq;
+	if (r->start > 0)
+		return r->start;
 
-	if (wake_capable)
-		*wake_capable = irq_ctx.wake_capable;
+	ret = acpi_dev_get_gpio_irq_resource(adev, NULL, 0, r);
+	if (!ret)
+		return r->start;
 
-	return irq_ctx.irq;
+	return ret;
 }
 
 static int i2c_acpi_get_info(struct acpi_device *adev,
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 3bd48d4b6318f..8b8c7581a60c2 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -513,10 +513,10 @@  static int i2c_device_probe(struct device *dev)
 			if (irq == -EINVAL || irq == -ENODATA)
 				irq = of_irq_get(dev->of_node, 0);
 		} else if (ACPI_COMPANION(dev)) {
-			bool wake_capable;
+			struct resource r = {0};
 
-			irq = i2c_acpi_get_irq(client, &wake_capable);
-			if (irq > 0 && wake_capable)
+			irq = i2c_acpi_get_irq(client, &r);
+			if (irq > 0 && r.flags & IORESOURCE_IRQ_WAKECAPABLE)
 				client->flags |= I2C_CLIENT_WAKE;
 		}
 		if (irq == -EPROBE_DEFER) {
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 05b8b8dfa9bdd..b5dc559c49d11 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -61,11 +61,11 @@  static inline int __i2c_check_suspended(struct i2c_adapter *adap)
 #ifdef CONFIG_ACPI
 void i2c_acpi_register_devices(struct i2c_adapter *adap);
 
-int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable);
+int i2c_acpi_get_irq(struct i2c_client *client, struct resource *r);
 #else /* CONFIG_ACPI */
 static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
 
-static inline int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
+static inline int i2c_acpi_get_irq(struct i2c_client *client, struct resource *r)
 {
 	return 0;
 }