[v1,1/6] gpiolib: acpi: Modify acpi_dev_irq_wake_get_by to use resource

Message ID 20231213110009.v1.1.Ifd0903f1c351e84376d71dbdadbd43931197f5ea@changeid
State New
Headers
Series [v1,1/6] gpiolib: acpi: Modify acpi_dev_irq_wake_get_by to use resource |

Commit Message

Mark Hasemeyer Dec. 13, 2023, 6 p.m. UTC
  Other information besides wake capability can be provided about GPIO
IRQs such as triggering, polarity, and sharability. Use resource flags
to provide this information to the caller if they want it.

This should keep the API more robust over time as flags are added,
modified, or removed. It also more closely matches acpi_irq_get which
take a resource as an argument.

Rename the function to acpi_dev_get_gpio_irq_resource to better describe
the function's new behavior.

Signed-off-by: Mark Hasemeyer <markhas@chromium.org>
---

 drivers/gpio/gpiolib-acpi.c | 25 ++++++++++++++++---------
 drivers/i2c/i2c-core-acpi.c | 10 ++++++++--
 include/linux/acpi.h        | 23 ++++++++++-------------
 3 files changed, 34 insertions(+), 24 deletions(-)
  

Comments

Andy Shevchenko Dec. 13, 2023, 7:34 p.m. UTC | #1
On Wed, Dec 13, 2023 at 11:00:19AM -0700, Mark Hasemeyer wrote:
> Other information besides wake capability can be provided about GPIO
> IRQs such as triggering, polarity, and sharability. Use resource flags
> to provide this information to the caller if they want it.
> 
> This should keep the API more robust over time as flags are added,
> modified, or removed. It also more closely matches acpi_irq_get which

acpi_irq_get()

> take a resource as an argument.
> 
> Rename the function to acpi_dev_get_gpio_irq_resource to better describe

acpi_dev_get_gpio_irq_resource()

> the function's new behavior.

...

> + * @r: pointer to resource to populate with irq information. It is not modified on failure.

IRQ

I don't think the second remark is even needed. It's usual approach, i.e.
we expect no changes in the output if error condition is met.

...

> + * Irq number will be available in the resource structure.

IRQ

...

> +			*r = (struct resource)DEFINE_RES_IRQ(irq);

Why do you need "(struct resource)" annotation?

...

> +	struct resource irqres;
>  	struct i2c_acpi_irq_context irq_ctx = {
>  		.irq = -ENOENT,
>  	};

Hmm... I'm wondering if we can reuse irqres as a context to the respective
lookup calls.
  
Andy Shevchenko Dec. 13, 2023, 7:40 p.m. UTC | #2
On Wed, Dec 13, 2023 at 11:00:19AM -0700, Mark Hasemeyer wrote:
> Other information besides wake capability can be provided about GPIO
> IRQs such as triggering, polarity, and sharability. Use resource flags
> to provide this information to the caller if they want it.
> 
> This should keep the API more robust over time as flags are added,
> modified, or removed. It also more closely matches acpi_irq_get which
> take a resource as an argument.
> 
> Rename the function to acpi_dev_get_gpio_irq_resource to better describe
> the function's new behavior.

I have got only one patch out of 6.
Also the series is missing a cover letter.

Please, fix both issues in the next version of the series.
  
Mark Hasemeyer Dec. 14, 2023, 8:56 p.m. UTC | #3
> > +                     *r = (struct resource)DEFINE_RES_IRQ(irq);
>
> Why do you need "(struct resource)" annotation?

I don't. I originally started working on this patch on a kernel
version that didn't have 52c4d11f1dce ("resource: Convert
DEFINE_RES_NAMED() to be compound literal").

> > +     struct resource irqres;
> >       struct i2c_acpi_irq_context irq_ctx = {
> >               .irq = -ENOENT,
> >       };
>
> Hmm... I'm wondering if we can reuse irqres as a context to the respective
> lookup calls.

I'll see if I can safely remove it.
  

Patch

diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 51e41676de0b8..3f6d28e1860f9 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -111,6 +111,7 @@  struct acpi_gpio_info {
 	int polarity;
 	int triggering;
 	bool wake_capable;
+	bool shareable;
 	unsigned int debounce;
 	unsigned int quirks;
 };
@@ -784,6 +785,7 @@  static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
 		lookup->info.debounce = agpio->debounce_timeout;
 		lookup->info.gpioint = gpioint;
 		lookup->info.wake_capable = acpi_gpio_irq_is_wake(&lookup->info.adev->dev, agpio);
+		lookup->info.shareable = agpio->shareable == ACPI_SHARED;
 
 		/*
 		 * Polarity and triggering are only specified for GpioInt
@@ -1028,11 +1030,11 @@  struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
 }
 
 /**
- * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number
+ * acpi_dev_get_gpio_irq_resource() - Find GpioInt and populate resource struct
  * @adev: pointer to a ACPI device to get IRQ from
  * @name: optional name of GpioInt resource
  * @index: index of GpioInt resource (starting from %0)
- * @wake_capable: Set to true if the IRQ is wake capable
+ * @r: pointer to resource to populate with irq information. It is not modified on failure.
  *
  * If the device has one or more GpioInt resources, this function can be
  * used to translate from the GPIO offset in the resource to the Linux IRQ
@@ -1047,10 +1049,12 @@  struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
  * The GPIO is considered wake capable if the GpioInt resource specifies
  * SharedAndWake or ExclusiveAndWake.
  *
- * Return: Linux IRQ number (> %0) on success, negative errno on failure.
+ * Irq number will be available in the resource structure.
+ *
+ * Return: 0 on success, negative errno on failure.
  */
-int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name, int index,
-				  bool *wake_capable)
+int acpi_dev_get_gpio_irq_resource(struct acpi_device *adev, const char *name, int index,
+				   struct resource *r)
 {
 	int idx, i;
 	unsigned int irq_flags;
@@ -1108,16 +1112,19 @@  int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name, in
 			}
 
 			/* avoid suspend issues with GPIOs when systems are using S3 */
-			if (wake_capable && acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0)
-				*wake_capable = info.wake_capable;
+			if (info.wake_capable && !(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
+				info.wake_capable = false;
 
-			return irq;
+			*r = (struct resource)DEFINE_RES_IRQ(irq);
+			r->flags = acpi_dev_irq_flags(info.triggering, info.polarity,
+						      info.shareable, info.wake_capable);
+			return 0;
 		}
 
 	}
 	return -ENOENT;
 }
-EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_wake_get_by);
+EXPORT_SYMBOL_GPL(acpi_dev_get_gpio_irq_resource);
 
 static acpi_status
 acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 69c50e8506d32..b89bc383ff627 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -203,6 +203,7 @@  int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
 {
 	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,
 	};
@@ -217,8 +218,13 @@  int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
 
 	acpi_dev_free_resource_list(&resource_list);
 
-	if (irq_ctx.irq == -ENOENT)
-		irq_ctx.irq = acpi_dev_gpio_irq_wake_get(adev, 0, &irq_ctx.wake_capable);
+	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;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index afd94c9b8b8af..20d9f3d088dbc 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1238,8 +1238,8 @@  bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
 				struct acpi_resource_gpio **agpio);
 bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
 			       struct acpi_resource_gpio **agpio);
-int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name, int index,
-				  bool *wake_capable);
+int acpi_dev_get_gpio_irq_resource(struct acpi_device *adev, const char *name, int index,
+				   struct resource *r);
 #else
 static inline bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
 					      struct acpi_resource_gpio **agpio)
@@ -1251,28 +1251,25 @@  static inline bool acpi_gpio_get_io_resource(struct acpi_resource *ares,
 {
 	return false;
 }
-static inline int acpi_dev_gpio_irq_wake_get_by(struct acpi_device *adev, const char *name,
-						int index, bool *wake_capable)
+static inline int acpi_dev_get_gpio_irq_resource(struct acpi_device *adev, const char *name,
+						 int index, struct resource *r)
 {
 	return -ENXIO;
 }
 #endif
 
-static inline int acpi_dev_gpio_irq_wake_get(struct acpi_device *adev, int index,
-					     bool *wake_capable)
+static inline int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int index)
 {
-	return acpi_dev_gpio_irq_wake_get_by(adev, NULL, index, wake_capable);
-}
+	struct resource r;
+	int ret;
 
-static inline int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name,
-					   int index)
-{
-	return acpi_dev_gpio_irq_wake_get_by(adev, name, index, NULL);
+	ret = acpi_dev_get_gpio_irq_resource(adev, name, index, &r);
+	return ret ?: r.start;
 }
 
 static inline int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
 {
-	return acpi_dev_gpio_irq_wake_get_by(adev, NULL, index, NULL);
+	return acpi_dev_gpio_irq_get_by(adev, NULL, index);
 }
 
 /* Device properties */