[PATCH v4 0/7] I2C IRQ Probe Improvements

[PATCH v4 0/7] I2C IRQ Probe Improvements

[Charles Keepax]

This series attempts to align as much IRQ handling into the
probe path as possible. Note that I don't have a great setup
for testing these patches so they are mostly just build tested
and need careful review and testing before any of them are
merged.

The series brings the ACPI path inline with the way the device
tree path handles the IRQ entirely at probe time. However,
it still leaves any IRQ specified through the board_info as
being handled at device time. In that case we need to cache
something from the board_info until probe time, which leaves
any alternative solution with something basically the same as
the current handling although perhaps caching more stuff.

Thanks,
Charles

See previous discussions:
 - https://lkml.org/lkml/2019/2/15/989
 - https://www.spinics.net/lists/linux-i2c/msg39541.html

Charles Keepax (7):
  i2c: core: Allow whole core to use i2c_dev_irq_from_resources
  i2c: acpi: Use available IRQ helper functions
  i2c: acpi: Factor out getting the IRQ from ACPI
  i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core
  i2c: core: Move ACPI IRQ handling to probe time
  i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
  i2c: core: Tidy up handling of init_irq

 drivers/i2c/i2c-core-acpi.c | 58 ++++++++++++++++++++++++++++++++-------------
 drivers/i2c/i2c-core-base.c | 11 +++++----
 drivers/i2c/i2c-core.h      |  9 +++++++
 3 files changed, 56 insertions(+), 22 deletions(-)

-- 
2.11.0

[PATCH v4 1/7] i2c: core: Allow whole core to use i2c_dev_irq_from_resources

[Charles Keepax]

Remove the static from i2c_dev_irq_from _resources so that other parts
of the core code can use this helper function.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

No changes since v3.

Thanks,
Charles

 drivers/i2c/i2c-core-base.c | 4 ++--
 drivers/i2c/i2c-core.h      | 2 ++
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 9e43508d4567d..67344586de913 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -679,8 +679,8 @@ static void i2c_dev_set_name(struct i2c_adapter *adap,
 		     i2c_encode_flags_to_addr(client));
 }
 
-static int i2c_dev_irq_from_resources(const struct resource *resources,
-				      unsigned int num_resources)
+int i2c_dev_irq_from_resources(const struct resource *resources,
+			       unsigned int num_resources)
 {
 	struct irq_data *irqd;
 	int i;
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 851c11b4c0f3a..2a3b28bf826b1 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -19,6 +19,8 @@ extern struct list_head	__i2c_board_list;
 extern int		__i2c_first_dynamic_bus_num;
 
 int i2c_check_7bit_addr_validity_strict(unsigned short addr);
+int i2c_dev_irq_from_resources(const struct resource *resources,
+			       unsigned int num_resources);
 
 /*
  * We only allow atomic transfers for very late communication, e.g. to send
-- 
2.11.0

[PATCH v4 2/7] i2c: acpi: Use available IRQ helper functions

[Charles Keepax]

Use the available IRQ helper functions, most of the functions have
additional helpful side affects like configuring the trigger type of the
IRQ.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

No changes since v3.

Apologies Andy but I really can't see a sensible way to split this
patch up. I have tried moving the resource_list_for_each_loop
into a function in one patch then switching to using
acpi_dev_resource_interrupt and i2c_dev_irq_from_resource, but the
function is basically a completely different function ie. all the
arguments are different and the purpose is different. So it makes
no sense, and it is very ping pong. I tried doing the switch to
i2c_dev_irq_from_resources as a separate patch which isn't so bad,
but feels pointless as it is such a small change, let me know if you
really want me to send that version.

Basically the switch to the helper function and the use of
acpi_dev_resource_interrupt are intrinsically linked, so there isn't
really a sensible way to split those up. If you still want some
changes I am afraid you will have to be more specific in what you are
looking for.

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index f1d648962b223..47d5b1c5ec9e0 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -133,14 +133,25 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,
 	return 0;
 }
 
+static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
+{
+	int *irq = data;
+	struct resource r;
+
+	if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
+		*irq = i2c_dev_irq_from_resources(&r, 1);
+
+	return 1; /* No need to add resource to the list */
+}
+
 static int i2c_acpi_get_info(struct acpi_device *adev,
 			     struct i2c_board_info *info,
 			     struct i2c_adapter *adapter,
 			     acpi_handle *adapter_handle)
 {
 	struct list_head resource_list;
-	struct resource_entry *entry;
 	struct i2c_acpi_lookup lookup;
+	int irq = -ENOENT;
 	int ret;
 
 	memset(&lookup, 0, sizeof(lookup));
@@ -172,16 +183,13 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
 
 	/* Then fill IRQ number if any */
 	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     i2c_acpi_add_resource, &irq);
 	if (ret < 0)
 		return -EINVAL;
 
-	resource_list_for_each_entry(entry, &resource_list) {
-		if (resource_type(entry->res) == IORESOURCE_IRQ) {
-			info->irq = entry->res->start;
-			break;
-		}
-	}
+	if (irq > 0)
+		info->irq = irq;
 
 	acpi_dev_free_resource_list(&resource_list);
 
-- 
2.11.0

[PATCH v4 3/7] i2c: acpi: Factor out getting the IRQ from ACPI

[Charles Keepax]

In preparation for future refactoring factor out the fetch of the IRQ
into its own helper function.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

No changes since v3.

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 33 +++++++++++++++++++++------------
 1 file changed, 21 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 47d5b1c5ec9e0..7d4d66ba752d4 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -144,14 +144,30 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
 	return 1; /* No need to add resource to the list */
 }
 
+static int i2c_acpi_get_irq(struct acpi_device *adev)
+{
+	struct list_head resource_list;
+	int irq = -ENOENT;
+	int ret;
+
+	INIT_LIST_HEAD(&resource_list);
+
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     i2c_acpi_add_resource, &irq);
+	if (ret < 0)
+		return -EINVAL;
+
+	acpi_dev_free_resource_list(&resource_list);
+
+	return irq;
+}
+
 static int i2c_acpi_get_info(struct acpi_device *adev,
 			     struct i2c_board_info *info,
 			     struct i2c_adapter *adapter,
 			     acpi_handle *adapter_handle)
 {
-	struct list_head resource_list;
 	struct i2c_acpi_lookup lookup;
-	int irq = -ENOENT;
 	int ret;
 
 	memset(&lookup, 0, sizeof(lookup));
@@ -182,16 +198,9 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
 		*adapter_handle = lookup.adapter_handle;
 
 	/* Then fill IRQ number if any */
-	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list,
-				     i2c_acpi_add_resource, &irq);
-	if (ret < 0)
-		return -EINVAL;
-
-	if (irq > 0)
-		info->irq = irq;
-
-	acpi_dev_free_resource_list(&resource_list);
+	ret = i2c_acpi_get_irq(adev);
+	if (ret > 0)
+		info->irq = ret;
 
 	acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
 			  sizeof(info->type));
-- 
2.11.0

[PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Charles Keepax]

In preparation for more refactoring make i2c_acpi_get_irq available
outside i2c-core-acpi.c.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

Changes since v3:
 - Move the change to use the helper function from i2c-core-base into its own patch.

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
 drivers/i2c/i2c-core.h      |  7 +++++++
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 7d4d66ba752d4..35966cc337dde 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
 	return 1; /* No need to add resource to the list */
 }
 
-static int i2c_acpi_get_irq(struct acpi_device *adev)
+/**
+ * i2c_acpi_get_irq - get device IRQ number from ACPI
+ * @client: Pointer to the I2C client device
+ *
+ * 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)
 {
+	struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
 	struct list_head resource_list;
 	int irq = -ENOENT;
 	int ret;
@@ -162,6 +171,8 @@ static int i2c_acpi_get_irq(struct acpi_device *adev)
 	return irq;
 }
 
+static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev);
+
 static int i2c_acpi_get_info(struct acpi_device *adev,
 			     struct i2c_board_info *info,
 			     struct i2c_adapter *adapter,
@@ -198,7 +209,7 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
 		*adapter_handle = lookup.adapter_handle;
 
 	/* Then fill IRQ number if any */
-	ret = i2c_acpi_get_irq(adev);
+	ret = i2c_acpi_get_irq(i2c_acpi_find_client_by_adev(adev));
 	if (ret > 0)
 		info->irq = ret;
 
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 2a3b28bf826b1..517d98be68d25 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -63,6 +63,8 @@ const struct acpi_device_id *
 i2c_acpi_match_device(const struct acpi_device_id *matches,
 		      struct i2c_client *client);
 void i2c_acpi_register_devices(struct i2c_adapter *adap);
+
+int i2c_acpi_get_irq(struct i2c_client *client);
 #else /* CONFIG_ACPI */
 static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
 static inline const struct acpi_device_id *
@@ -71,6 +73,11 @@ i2c_acpi_match_device(const struct acpi_device_id *matches,
 {
 	return NULL;
 }
+
+static inline int i2c_acpi_get_irq(struct i2c_client *client)
+{
+	return 0;
+}
 #endif /* CONFIG_ACPI */
 extern struct notifier_block i2c_acpi_notifier;
 
-- 
2.11.0

[PATCH v4 5/7] i2c: core: Move ACPI IRQ handling to probe time

[Charles Keepax]

Bring the ACPI path in sync with the device tree path and handle all the
IRQ fetching at probe time. This leaves the only IRQ handling at device
registration time being that which is passed directly through the board
info as either a resource or an actual IRQ number.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

New since v3, but this patch and the previous one leave the code in
the same state as this patch did on v3.

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 7 -------
 drivers/i2c/i2c-core-base.c | 5 ++++-
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 35966cc337dde..c70228f5349ef 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -171,8 +171,6 @@ int i2c_acpi_get_irq(struct i2c_client *client)
 	return irq;
 }
 
-static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev);
-
 static int i2c_acpi_get_info(struct acpi_device *adev,
 			     struct i2c_board_info *info,
 			     struct i2c_adapter *adapter,
@@ -208,11 +206,6 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
 	if (adapter_handle)
 		*adapter_handle = lookup.adapter_handle;
 
-	/* Then fill IRQ number if any */
-	ret = i2c_acpi_get_irq(i2c_acpi_find_client_by_adev(adev));
-	if (ret > 0)
-		info->irq = ret;
-
 	acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
 			  sizeof(info->type));
 
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 67344586de913..9520bcfc83182 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -327,7 +327,10 @@ 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)) {
-			irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
+			irq = i2c_acpi_get_irq(client);
+
+			if (irq == -ENOENT)
+				irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
 		}
 		if (irq == -EPROBE_DEFER)
 			return irq;
-- 
2.11.0

[PATCH v4 6/7] i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq

[Charles Keepax]

It makes sense to contain all the ACPI IRQ handling in a single helper
function.

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

No change since v3.

Thanks,
Charles

 drivers/i2c/i2c-core-acpi.c | 3 +++
 drivers/i2c/i2c-core-base.c | 3 ---
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index c70228f5349ef..b3ccd2dda0fc1 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -168,6 +168,9 @@ int i2c_acpi_get_irq(struct i2c_client *client)
 
 	acpi_dev_free_resource_list(&resource_list);
 
+	if (irq == -ENOENT)
+		irq = acpi_dev_gpio_irq_get(adev, 0);
+
 	return irq;
 }
 
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 9520bcfc83182..6be2e3a4784fa 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -328,9 +328,6 @@ static int i2c_device_probe(struct device *dev)
 				irq = of_irq_get(dev->of_node, 0);
 		} else if (ACPI_COMPANION(dev)) {
 			irq = i2c_acpi_get_irq(client);
-
-			if (irq == -ENOENT)
-				irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
 		}
 		if (irq == -EPROBE_DEFER)
 			return irq;
-- 
2.11.0

[PATCH v4 7/7] i2c: core: Tidy up handling of init_irq

[Charles Keepax]

Only set init_irq during i2c_device_new and only handle client->irq on
the probe/remove paths.

Suggested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
---

No change since v3.

Thanks,
Charles

 drivers/i2c/i2c-core-base.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 6be2e3a4784fa..9b52427dc7c94 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -314,6 +314,8 @@ static int i2c_device_probe(struct device *dev)
 
 	driver = to_i2c_driver(dev->driver);
 
+	client->irq = client->init_irq;
+
 	if (!client->irq && !driver->disable_i2c_core_irq_mapping) {
 		int irq = -ENOENT;
 
@@ -424,7 +426,7 @@ static int i2c_device_remove(struct device *dev)
 	dev_pm_clear_wake_irq(&client->dev);
 	device_init_wakeup(&client->dev, false);
 
-	client->irq = client->init_irq;
+	client->irq = 0;
 	if (client->flags & I2C_CLIENT_HOST_NOTIFY)
 		pm_runtime_put(&client->adapter->dev);
 
@@ -741,7 +743,6 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *inf
 	if (!client->init_irq)
 		client->init_irq = i2c_dev_irq_from_resources(info->resources,
 							 info->num_resources);
-	client->irq = client->init_irq;
 
 	strlcpy(client->name, info->type, sizeof(client->name));
 
-- 
2.11.0

Re: [PATCH v4 2/7] i2c: acpi: Use available IRQ helper functions

[Andy Shevchenko]

On Tue, Jun 11, 2019 at 01:30:56PM +0100, Charles Keepax wrote:
> Use the available IRQ helper functions, most of the functions have
> additional helpful side affects like configuring the trigger type of the
> IRQ.
> 
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> ---
> 
> No changes since v3.
> 
> Apologies Andy but I really can't see a sensible way to split this
> patch up. I have tried moving the resource_list_for_each_loop
> into a function in one patch then switching to using
> acpi_dev_resource_interrupt and i2c_dev_irq_from_resource, but the
> function is basically a completely different function ie. all the
> arguments are different and the purpose is different. So it makes
> no sense, and it is very ping pong. I tried doing the switch to
> i2c_dev_irq_from_resources as a separate patch which isn't so bad,
> but feels pointless as it is such a small change, let me know if you
> really want me to send that version.
> 
> Basically the switch to the helper function and the use of
> acpi_dev_resource_interrupt are intrinsically linked, so there isn't
> really a sensible way to split those up. If you still want some
> changes I am afraid you will have to be more specific in what you are
> looking for.

It seems I missed few details, thus the current approach works for me, thanks!

> 
> Thanks,
> Charles
> 
>  drivers/i2c/i2c-core-acpi.c | 24 ++++++++++++++++--------
>  1 file changed, 16 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> index f1d648962b223..47d5b1c5ec9e0 100644
> --- a/drivers/i2c/i2c-core-acpi.c
> +++ b/drivers/i2c/i2c-core-acpi.c
> @@ -133,14 +133,25 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,
>  	return 0;
>  }
>  
> +static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
> +{
> +	int *irq = data;
> +	struct resource r;
> +
> +	if (*irq <= 0 && acpi_dev_resource_interrupt(ares, 0, &r))
> +		*irq = i2c_dev_irq_from_resources(&r, 1);
> +
> +	return 1; /* No need to add resource to the list */
> +}
> +
>  static int i2c_acpi_get_info(struct acpi_device *adev,
>  			     struct i2c_board_info *info,
>  			     struct i2c_adapter *adapter,
>  			     acpi_handle *adapter_handle)
>  {
>  	struct list_head resource_list;
> -	struct resource_entry *entry;
>  	struct i2c_acpi_lookup lookup;
> +	int irq = -ENOENT;
>  	int ret;
>  
>  	memset(&lookup, 0, sizeof(lookup));
> @@ -172,16 +183,13 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
>  
>  	/* Then fill IRQ number if any */
>  	INIT_LIST_HEAD(&resource_list);
> -	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
> +	ret = acpi_dev_get_resources(adev, &resource_list,
> +				     i2c_acpi_add_resource, &irq);
>  	if (ret < 0)
>  		return -EINVAL;
>  
> -	resource_list_for_each_entry(entry, &resource_list) {
> -		if (resource_type(entry->res) == IORESOURCE_IRQ) {
> -			info->irq = entry->res->start;
> -			break;
> -		}
> -	}
> +	if (irq > 0)
> +		info->irq = irq;
>  
>  	acpi_dev_free_resource_list(&resource_list);
>  
> -- 
> 2.11.0
> 

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 0/7] I2C IRQ Probe Improvements

[Andy Shevchenko]

On Tue, Jun 11, 2019 at 01:30:54PM +0100, Charles Keepax wrote:
> This series attempts to align as much IRQ handling into the
> probe path as possible. Note that I don't have a great setup
> for testing these patches so they are mostly just build tested
> and need careful review and testing before any of them are
> merged.
> 
> The series brings the ACPI path inline with the way the device
> tree path handles the IRQ entirely at probe time. However,
> it still leaves any IRQ specified through the board_info as
> being handled at device time. In that case we need to cache
> something from the board_info until probe time, which leaves
> any alternative solution with something basically the same as
> the current handling although perhaps caching more stuff.

Thank you!
This one looks good.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> 
> Thanks,
> Charles
> 
> See previous discussions:
>  - https://lkml.org/lkml/2019/2/15/989
>  - https://www.spinics.net/lists/linux-i2c/msg39541.html
> 
> Charles Keepax (7):
>   i2c: core: Allow whole core to use i2c_dev_irq_from_resources
>   i2c: acpi: Use available IRQ helper functions
>   i2c: acpi: Factor out getting the IRQ from ACPI
>   i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core
>   i2c: core: Move ACPI IRQ handling to probe time
>   i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
>   i2c: core: Tidy up handling of init_irq
> 
>  drivers/i2c/i2c-core-acpi.c | 58 ++++++++++++++++++++++++++++++++-------------
>  drivers/i2c/i2c-core-base.c | 11 +++++----
>  drivers/i2c/i2c-core.h      |  9 +++++++
>  3 files changed, 56 insertions(+), 22 deletions(-)
> 
> -- 
> 2.11.0
> 

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 0/7] I2C IRQ Probe Improvements

[Benjamin Tissoires]

On Tue, Jun 11, 2019 at 2:31 PM Charles Keepax
<ckeepax@opensource.cirrus.com> wrote:
>
> This series attempts to align as much IRQ handling into the
> probe path as possible. Note that I don't have a great setup
> for testing these patches so they are mostly just build tested
> and need careful review and testing before any of them are
> merged.
>
> The series brings the ACPI path inline with the way the device
> tree path handles the IRQ entirely at probe time. However,
> it still leaves any IRQ specified through the board_info as
> being handled at device time. In that case we need to cache
> something from the board_info until probe time, which leaves
> any alternative solution with something basically the same as
> the current handling although perhaps caching more stuff.

Hmm, I still haven't pinpointed the issue, but I wanted to give a test
of the series and I have:
[    5.511806] i2c_hid i2c-DLL075B:01: HID over i2c has not been
provided an Int IRQ
[    5.511825] i2c_hid: probe of i2c-DLL075B:01 failed with error -22

So it seems that there is something wrong happening when fetching the
IRQ and providing it to i2c-hid.

That was on a Dell XPS 9360.

Bisecting is starting.

Cheers,
Benjamin

>
> Thanks,
> Charles
>
> See previous discussions:
>  - https://lkml.org/lkml/2019/2/15/989
>  - https://www.spinics.net/lists/linux-i2c/msg39541.html
>
> Charles Keepax (7):
>   i2c: core: Allow whole core to use i2c_dev_irq_from_resources
>   i2c: acpi: Use available IRQ helper functions
>   i2c: acpi: Factor out getting the IRQ from ACPI
>   i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core
>   i2c: core: Move ACPI IRQ handling to probe time
>   i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
>   i2c: core: Tidy up handling of init_irq
>
>  drivers/i2c/i2c-core-acpi.c | 58 ++++++++++++++++++++++++++++++++-------------
>  drivers/i2c/i2c-core-base.c | 11 +++++----
>  drivers/i2c/i2c-core.h      |  9 +++++++
>  3 files changed, 56 insertions(+), 22 deletions(-)
>
> --
> 2.11.0
>

Re: [PATCH v4 0/7] I2C IRQ Probe Improvements

[Charles Keepax]

On Tue, Jun 11, 2019 at 05:16:58PM +0200, Benjamin Tissoires wrote:
> On Tue, Jun 11, 2019 at 2:31 PM Charles Keepax
> <ckeepax@opensource.cirrus.com> wrote:
> >
> > This series attempts to align as much IRQ handling into the
> > probe path as possible. Note that I don't have a great setup
> > for testing these patches so they are mostly just build tested
> > and need careful review and testing before any of them are
> > merged.
> >
> > The series brings the ACPI path inline with the way the device
> > tree path handles the IRQ entirely at probe time. However,
> > it still leaves any IRQ specified through the board_info as
> > being handled at device time. In that case we need to cache
> > something from the board_info until probe time, which leaves
> > any alternative solution with something basically the same as
> > the current handling although perhaps caching more stuff.
> 
> Hmm, I still haven't pinpointed the issue, but I wanted to give a test
> of the series and I have:
> [    5.511806] i2c_hid i2c-DLL075B:01: HID over i2c has not been
> provided an Int IRQ
> [    5.511825] i2c_hid: probe of i2c-DLL075B:01 failed with error -22
> 
> So it seems that there is something wrong happening when fetching the
> IRQ and providing it to i2c-hid.
> 
> That was on a Dell XPS 9360.
> 
> Bisecting is starting.
> 

I have a sneaking suspision, does this diff fix it:

diff --git a/drivers/i2c/i2c-core-acpi.c
b/drivers/i2c/i2c-core-acpi.c
index 57be6342ba508..a90b05a269c36 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -169,7 +169,7 @@ int i2c_acpi_get_irq(struct i2c_client *client)
        acpi_dev_free_resource_list(&resource_list);

        if (irq == -ENOENT)
-           irq = acpi_dev_gpio_irq_get(adev, 0);
+         irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(&client->dev), 0);

        return irq;
 }

There was some earlier discussion about which device was suitable
for this call.

Thanks,
Charles

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Mika Westerberg]

On Tue, Jun 11, 2019 at 01:30:58PM +0100, Charles Keepax wrote:
> In preparation for more refactoring make i2c_acpi_get_irq available
> outside i2c-core-acpi.c.
> 
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Benjamin Tissoires]

On Tue, Jun 11, 2019 at 2:31 PM Charles Keepax
<ckeepax@opensource.cirrus.com> wrote:
>
> In preparation for more refactoring make i2c_acpi_get_irq available
> outside i2c-core-acpi.c.
>
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> ---

So, my bisect fails here: when I recompile the vmlinuz image, it fails
after loading the initrd. There is no boot up message, so not sure,
but the problem with the non working touchpad is either this one or
the next one.

Cheers,
Benjamin

>
> Changes since v3:
>  - Move the change to use the helper function from i2c-core-base into its own patch.
>
> Thanks,
> Charles
>
>  drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
>  drivers/i2c/i2c-core.h      |  7 +++++++
>  2 files changed, 20 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> index 7d4d66ba752d4..35966cc337dde 100644
> --- a/drivers/i2c/i2c-core-acpi.c
> +++ b/drivers/i2c/i2c-core-acpi.c
> @@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
>         return 1; /* No need to add resource to the list */
>  }
>
> -static int i2c_acpi_get_irq(struct acpi_device *adev)
> +/**
> + * i2c_acpi_get_irq - get device IRQ number from ACPI
> + * @client: Pointer to the I2C client device
> + *
> + * 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)
>  {
> +       struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
>         struct list_head resource_list;
>         int irq = -ENOENT;
>         int ret;
> @@ -162,6 +171,8 @@ static int i2c_acpi_get_irq(struct acpi_device *adev)
>         return irq;
>  }
>
> +static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev);
> +
>  static int i2c_acpi_get_info(struct acpi_device *adev,
>                              struct i2c_board_info *info,
>                              struct i2c_adapter *adapter,
> @@ -198,7 +209,7 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
>                 *adapter_handle = lookup.adapter_handle;
>
>         /* Then fill IRQ number if any */
> -       ret = i2c_acpi_get_irq(adev);
> +       ret = i2c_acpi_get_irq(i2c_acpi_find_client_by_adev(adev));
>         if (ret > 0)
>                 info->irq = ret;
>
> diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
> index 2a3b28bf826b1..517d98be68d25 100644
> --- a/drivers/i2c/i2c-core.h
> +++ b/drivers/i2c/i2c-core.h
> @@ -63,6 +63,8 @@ const struct acpi_device_id *
>  i2c_acpi_match_device(const struct acpi_device_id *matches,
>                       struct i2c_client *client);
>  void i2c_acpi_register_devices(struct i2c_adapter *adap);
> +
> +int i2c_acpi_get_irq(struct i2c_client *client);
>  #else /* CONFIG_ACPI */
>  static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
>  static inline const struct acpi_device_id *
> @@ -71,6 +73,11 @@ i2c_acpi_match_device(const struct acpi_device_id *matches,
>  {
>         return NULL;
>  }
> +
> +static inline int i2c_acpi_get_irq(struct i2c_client *client)
> +{
> +       return 0;
> +}
>  #endif /* CONFIG_ACPI */
>  extern struct notifier_block i2c_acpi_notifier;
>
> --
> 2.11.0
>

Re: [PATCH v4 0/7] I2C IRQ Probe Improvements

[Benjamin Tissoires]

On Tue, Jun 11, 2019 at 5:29 PM Charles Keepax
<ckeepax@opensource.cirrus.com> wrote:
>
> On Tue, Jun 11, 2019 at 05:16:58PM +0200, Benjamin Tissoires wrote:
> > On Tue, Jun 11, 2019 at 2:31 PM Charles Keepax
> > <ckeepax@opensource.cirrus.com> wrote:
> > >
> > > This series attempts to align as much IRQ handling into the
> > > probe path as possible. Note that I don't have a great setup
> > > for testing these patches so they are mostly just build tested
> > > and need careful review and testing before any of them are
> > > merged.
> > >
> > > The series brings the ACPI path inline with the way the device
> > > tree path handles the IRQ entirely at probe time. However,
> > > it still leaves any IRQ specified through the board_info as
> > > being handled at device time. In that case we need to cache
> > > something from the board_info until probe time, which leaves
> > > any alternative solution with something basically the same as
> > > the current handling although perhaps caching more stuff.
> >
> > Hmm, I still haven't pinpointed the issue, but I wanted to give a test
> > of the series and I have:
> > [    5.511806] i2c_hid i2c-DLL075B:01: HID over i2c has not been
> > provided an Int IRQ
> > [    5.511825] i2c_hid: probe of i2c-DLL075B:01 failed with error -22
> >
> > So it seems that there is something wrong happening when fetching the
> > IRQ and providing it to i2c-hid.
> >
> > That was on a Dell XPS 9360.
> >
> > Bisecting is starting.
> >
>
> I have a sneaking suspision, does this diff fix it:
>
> diff --git a/drivers/i2c/i2c-core-acpi.c
> b/drivers/i2c/i2c-core-acpi.c
> index 57be6342ba508..a90b05a269c36 100644
> --- a/drivers/i2c/i2c-core-acpi.c
> +++ b/drivers/i2c/i2c-core-acpi.c
> @@ -169,7 +169,7 @@ int i2c_acpi_get_irq(struct i2c_client *client)
>         acpi_dev_free_resource_list(&resource_list);
>
>         if (irq == -ENOENT)
> -           irq = acpi_dev_gpio_irq_get(adev, 0);
> +         irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(&client->dev), 0);
>
>         return irq;
>  }
>

Unfortunately, this doesn't solve the issue.

The problem is either in 4/7 or 5/7 (4/7 doesn't boot AFAICT).

(chasing multiple rabbits at the same time, so hard to get to the bottom of it)

Cheers,
Benjamin

> There was some earlier discussion about which device was suitable
> for this call.
>
> Thanks,
> Charles

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Mika Westerberg]

On Tue, Jun 11, 2019 at 01:30:58PM +0100, Charles Keepax wrote:
> In preparation for more refactoring make i2c_acpi_get_irq available
> outside i2c-core-acpi.c.
> 
> Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> ---
> 
> Changes since v3:
>  - Move the change to use the helper function from i2c-core-base into its own patch.
> 
> Thanks,
> Charles
> 
>  drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
>  drivers/i2c/i2c-core.h      |  7 +++++++
>  2 files changed, 20 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> index 7d4d66ba752d4..35966cc337dde 100644
> --- a/drivers/i2c/i2c-core-acpi.c
> +++ b/drivers/i2c/i2c-core-acpi.c
> @@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
>  	return 1; /* No need to add resource to the list */
>  }
>  
> -static int i2c_acpi_get_irq(struct acpi_device *adev)
> +/**
> + * i2c_acpi_get_irq - get device IRQ number from ACPI
> + * @client: Pointer to the I2C client device
> + *
> + * 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)
>  {
> +	struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);

Is this adev checked for being NULL somewhere below before it is being
dereferenced?

It could explain the issue Benjamin is seeing.

>  	struct list_head resource_list;
>  	int irq = -ENOENT;
>  	int ret;

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Charles Keepax]

On Wed, Jun 12, 2019 at 06:27:18PM +0300, Mika Westerberg wrote:
> On Tue, Jun 11, 2019 at 01:30:58PM +0100, Charles Keepax wrote:
> > In preparation for more refactoring make i2c_acpi_get_irq available
> > outside i2c-core-acpi.c.
> > 
> > Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> > ---
> > 
> > Changes since v3:
> >  - Move the change to use the helper function from i2c-core-base into its own patch.
> > 
> > Thanks,
> > Charles
> > 
> >  drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
> >  drivers/i2c/i2c-core.h      |  7 +++++++
> >  2 files changed, 20 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> > index 7d4d66ba752d4..35966cc337dde 100644
> > --- a/drivers/i2c/i2c-core-acpi.c
> > +++ b/drivers/i2c/i2c-core-acpi.c
> > @@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
> >  	return 1; /* No need to add resource to the list */
> >  }
> >  
> > -static int i2c_acpi_get_irq(struct acpi_device *adev)
> > +/**
> > + * i2c_acpi_get_irq - get device IRQ number from ACPI
> > + * @client: Pointer to the I2C client device
> > + *
> > + * 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)
> >  {
> > +	struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
> 
> Is this adev checked for being NULL somewhere below before it is being
> dereferenced?
> 
> It could explain the issue Benjamin is seeing.
> 

Yeah could be that or just for some reason this isn't returning
the same adev as we previously had. I will do some digging see if
I can find any likely culprits.

Thanks,
Charles

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Benjamin Tissoires]

On Thu, Jun 13, 2019 at 10:49 AM Charles Keepax
<ckeepax@opensource.cirrus.com> wrote:
>
> On Wed, Jun 12, 2019 at 06:27:18PM +0300, Mika Westerberg wrote:
> > On Tue, Jun 11, 2019 at 01:30:58PM +0100, Charles Keepax wrote:
> > > In preparation for more refactoring make i2c_acpi_get_irq available
> > > outside i2c-core-acpi.c.
> > >
> > > Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> > > ---
> > >
> > > Changes since v3:
> > >  - Move the change to use the helper function from i2c-core-base into its own patch.
> > >
> > > Thanks,
> > > Charles
> > >
> > >  drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
> > >  drivers/i2c/i2c-core.h      |  7 +++++++
> > >  2 files changed, 20 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> > > index 7d4d66ba752d4..35966cc337dde 100644
> > > --- a/drivers/i2c/i2c-core-acpi.c
> > > +++ b/drivers/i2c/i2c-core-acpi.c
> > > @@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
> > >     return 1; /* No need to add resource to the list */
> > >  }
> > >
> > > -static int i2c_acpi_get_irq(struct acpi_device *adev)
> > > +/**
> > > + * i2c_acpi_get_irq - get device IRQ number from ACPI
> > > + * @client: Pointer to the I2C client device
> > > + *
> > > + * 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)
> > >  {
> > > +   struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
> >
> > Is this adev checked for being NULL somewhere below before it is being
> > dereferenced?
> >
> > It could explain the issue Benjamin is seeing.
> >
>
> Yeah could be that or just for some reason this isn't returning
> the same adev as we previously had. I will do some digging see if
> I can find any likely culprits.

That was almost the culprit: client is NULL here.
So the call of i2c_acpi_find_client_by_adev(adev) fails.

I guess this explains why the next commit is also not working :)

Cheers,
Benjamin

Re: [PATCH v4 4/7] i2c: core: Make i2c_acpi_get_irq available to the rest of the I2C core

[Charles Keepax]

On Thu, Jun 13, 2019 at 11:32:47AM +0200, Benjamin Tissoires wrote:
> On Thu, Jun 13, 2019 at 10:49 AM Charles Keepax
> <ckeepax@opensource.cirrus.com> wrote:
> >
> > On Wed, Jun 12, 2019 at 06:27:18PM +0300, Mika Westerberg wrote:
> > > On Tue, Jun 11, 2019 at 01:30:58PM +0100, Charles Keepax wrote:
> > > > In preparation for more refactoring make i2c_acpi_get_irq available
> > > > outside i2c-core-acpi.c.
> > > >
> > > > Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
> > > > ---
> > > >
> > > > Changes since v3:
> > > >  - Move the change to use the helper function from i2c-core-base into its own patch.
> > > >
> > > > Thanks,
> > > > Charles
> > > >
> > > >  drivers/i2c/i2c-core-acpi.c | 15 +++++++++++++--
> > > >  drivers/i2c/i2c-core.h      |  7 +++++++
> > > >  2 files changed, 20 insertions(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
> > > > index 7d4d66ba752d4..35966cc337dde 100644
> > > > --- a/drivers/i2c/i2c-core-acpi.c
> > > > +++ b/drivers/i2c/i2c-core-acpi.c
> > > > @@ -144,8 +144,17 @@ static int i2c_acpi_add_resource(struct acpi_resource *ares, void *data)
> > > >     return 1; /* No need to add resource to the list */
> > > >  }
> > > >
> > > > -static int i2c_acpi_get_irq(struct acpi_device *adev)
> > > > +/**
> > > > + * i2c_acpi_get_irq - get device IRQ number from ACPI
> > > > + * @client: Pointer to the I2C client device
> > > > + *
> > > > + * 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)
> > > >  {
> > > > +   struct acpi_device *adev = ACPI_COMPANION(&client->adapter->dev);
> > >
> > > Is this adev checked for being NULL somewhere below before it is being
> > > dereferenced?
> > >
> > > It could explain the issue Benjamin is seeing.
> > >
> >
> > Yeah could be that or just for some reason this isn't returning
> > the same adev as we previously had. I will do some digging see if
> > I can find any likely culprits.
> 
> That was almost the culprit: client is NULL here.
> So the call of i2c_acpi_find_client_by_adev(adev) fails.
> 
> I guess this explains why the next commit is also not working :)
> 

Ah.. yeah because at this stage this code is probably running
before that client has been created I think, this crept in on
that last splitting of the patch into two. Let me see if I can
come up with a new solution and do a new version. Thank you very
much for the help going through this.

Thanks,
Charles