I2C IRQ Probe Improvements
Subsystems (4)
cover I2C IRQ Probe Improvements
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 (5):
i2c: acpi: Factor out getting the IRQ from ACPI
i2c: acpi: Use available IRQ helper functions
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 | 50 ++++++++++++++++++++++++++++++--------------- drivers/i2c/i2c-core-base.c | 11 +++++----- drivers/i2c/i2c-core.h | 9 ++++++++ 3 files changed, 48 insertions(+), 22 deletions(-)
Signature · 1 line
2.11.0
PATCH 1/5 i2c: acpi: Factor out getting the IRQ from ACPI
In preparation for future refactoring factor out the fetch of the IRQ into its own helper function.
--- drivers/i2c/i2c-core-acpi.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-)
drivers/i2c/i2c-core-acpi.c +25 -15
@@ -137,13 +137,35 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,return 0 ; } +static int i2c_acpi_get_irq (struct acpi_device *adev,int *irq) +{ +struct list_head resource_list; +struct resource_entry *entry; +int ret; + +INIT_LIST_HEAD (&resource_list); + + ret =acpi_dev_get_resources (adev, &resource_list,NULL ,NULL ); +if (ret <0 ) +return -EINVAL ; + +resource_list_for_each_entry (entry, &resource_list) { +if (resource_type (entry->res) ==IORESOURCE_IRQ ) { + *irq = entry->res->start; +break ; + } + } + +acpi_dev_free_resource_list (&resource_list); + +return 0 ; +} +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 ret;
@@ -175,19 +197,7 @@ 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,NULL ,NULL ); -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 ; - } - } - -acpi_dev_free_resource_list (&resource_list); +i2c_acpi_get_irq (adev, &info->irq);acpi_set_modalias (adev,dev_name (&adev->dev), info->type,sizeof (info->type));
Signature · 1 line
2.11.0
Re: [PATCH 1/5] i2c: acpi: Factor out getting the IRQ from ACPI
Quoted 13 lines · Charles Keepax
In preparation for future refactoring factor out the fetch of the IRQ into its own helper function.
Signed-off-by Charles Keepax <[email protected]>--- drivers/i2c/i2c-core-acpi.c | 40 +++++++++++++++++++++++++--------------- 1 file changed, 25 insertions(+), 15 deletions(-)drivers/i2c/i2c-core-acpi.c +0
-0
drivers/i2c/i2c-core-acpi.c static int i2c_acpi_do_lookup(struct acpi_device *adev, · line 140
Quoted 4 lines
drivers/i2c/i2c-core-acpi.c +1
-0@@ -137,13 +137,35 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,return 0 ; } +static int i2c_acpi_get_irq (struct acpi_device *adev,int *irq)
I think here the function should return irq instead, and negative errno in case of failure.
PATCH 2/5 i2c: acpi: Use available IRQ helper functions
In reply to Charles KeepaxUse the available IRQ helper functions, most of the functions have additional helpful side affects like configuring the trigger type of the IRQ.
--- drivers/i2c/i2c-core-acpi.c | 23 ++++++++++++++--------- drivers/i2c/i2c-core-base.c | 4 ++-- drivers/i2c/i2c-core.h | 2 ++ 3 files changed, 18 insertions(+), 11 deletions(-)
drivers/i2c/i2c-core-acpi.c +14 -9
@@ -137,25 +137,30 @@ 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_irq (struct acpi_device *adev,int *irq) {struct list_head resource_list; -struct resource_entry *entry;int ret;INIT_LIST_HEAD (&resource_list); + *irq = -ENOENT ; - 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 ) { - *irq = entry->res->start; -break ; - } - } -acpi_dev_free_resource_list (&resource_list);return 0 ;
drivers/i2c/i2c-core-base.c +2 -2
@@ -687,8 +687,8 @@ 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;
drivers/i2c/i2c-core.h +2 -0
@@ -28,6 +28,8 @@ 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
Signature · 1 line
2.11.0
PATCH 3/5 i2c: core: Move ACPI IRQ handling to probe time
In reply to Charles KeepaxBring 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.
--- drivers/i2c/i2c-core-acpi.c | 6 ++---- drivers/i2c/i2c-core-base.c | 6 +++++- drivers/i2c/i2c-core.h | 7 +++++++ 3 files changed, 14 insertions(+), 5 deletions(-)
drivers/i2c/i2c-core-acpi.c +2 -4
@@ -148,8 +148,9 @@ 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,int *irq) +int i2c_acpi_get_irq (struct i2c_client *client,int *irq) { +struct acpi_device *adev =ACPI_COMPANION (&client->adapter->dev);struct list_head resource_list;int ret;
@@ -201,9 +202,6 @@ static int i2c_acpi_get_info(struct acpi_device *adev,if (adapter_handle) *adapter_handle = lookup.adapter_handle; -/* Then fill IRQ number if any */ -i2c_acpi_get_irq (adev, &info->irq); -acpi_set_modalias (adev,dev_name (&adev->dev), info->type,sizeof (info->type));
drivers/i2c/i2c-core-base.c +5 -1
@@ -335,7 +335,11 @@ 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 ); +i2c_acpi_get_irq (client, &irq); + +if (irq == -ENOENT ) + irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (dev), +0 ); }if (irq == -EPROBE_DEFER )return irq;
drivers/i2c/i2c-core.h +7 -0
@@ -72,6 +72,8 @@ 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,int *irq);#else /* CONFIG_ACPI */ static inline void i2c_acpi_register_devices (struct i2c_adapter *adap) { } static inline const struct acpi_device_id *
@@ -80,6 +82,11 @@ i2c_acpi_match_device(const struct acpi_device_id *matches, {return NULL ; } + +static inline int i2c_acpi_get_irq (struct i2c_client *client,int *irq) +{ +return 0 ; +}#endif /* CONFIG_ACPI */ extern struct notifier_block i2c_acpi_notifier;
Signature · 1 line
2.11.0
Re: [PATCH 3/5] i2c: core: Move ACPI IRQ handling to probe time
Quoted 4 lines · 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.
I don't see issues with this approach. Cc'd Jarkko and Andy just in case I missed something.
One minor stylistic comment, see below.
Quoted 37 lines
Signed-off-by Charles Keepax <[email protected]>--- drivers/i2c/i2c-core-acpi.c | 6 ++---- drivers/i2c/i2c-core-base.c | 6 +++++- drivers/i2c/i2c-core.h | 7 +++++++ 3 files changed, 14 insertions(+), 5 deletions(-)drivers/i2c/i2c-core-acpi.c +2
-4@@ -148,8 +148,9 @@ 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,int *irq) +int i2c_acpi_get_irq (struct i2c_client *client,int *irq) { +struct acpi_device *adev =ACPI_COMPANION (&client->adapter->dev);struct list_head resource_list;int ret;@@ -201,9 +202,6 @@ static int i2c_acpi_get_info(struct acpi_device *adev,if (adapter_handle) *adapter_handle = lookup.adapter_handle; -/* Then fill IRQ number if any */ -i2c_acpi_get_irq (adev, &info->irq); -acpi_set_modalias (adev,dev_name (&adev->dev), info->type,sizeof (info->type));drivers/i2c/i2c-core-base.c +0
-0
drivers/i2c/i2c-core-base.c static int i2c_device_probe(struct device *dev) · line 342
Quoted 9 lines
drivers/i2c/i2c-core-base.c +5
-1@@ -335,7 +335,11 @@ 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 ); +i2c_acpi_get_irq (client, &irq); + +if (irq == -ENOENT ) + irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (dev), +0 );
I think this looks better if you put everything one line:
irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
Quoted 30 lines
drivers/i2c/i2c-core-base.c +0
-0}if (irq == -EPROBE_DEFER )return irq;drivers/i2c/i2c-core.h +7
-0@@ -72,6 +72,8 @@ 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,int *irq);#else /* CONFIG_ACPI */ static inline void i2c_acpi_register_devices (struct i2c_adapter *adap) { } static inline const struct acpi_device_id *@@ -80,6 +82,11 @@ i2c_acpi_match_device(const struct acpi_device_id *matches, {return NULL ; } + +static inline int i2c_acpi_get_irq (struct i2c_client *client,int *irq) +{ +return 0 ; +}#endif /* CONFIG_ACPI */ extern struct notifier_block i2c_acpi_notifier;Signature · 1 line
2.11.0
Re: [PATCH 3/5] i2c: core: Move ACPI IRQ handling to probe time
Quoted 8 lines · Mika Westerberg
Quoted 4 lines · 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.
I don't see issues with this approach. Cc'd Jarkko and Andy just in case I missed something.
I failed to see the i2c_acpi_get_irq() in the current code. What kernel version do you use?
Can we see the changes against vanilla / i2c-next?
Signature · 2 lines
With Best Regards, Andy Shevchenko
Re: [PATCH 3/5] i2c: core: Move ACPI IRQ handling to probe time
Quoted 7 lines · Andy Shevchenko
Quoted 6 lines · Mika Westerberg
Quoted 4 lines · 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.
Quoted 7 lines
Quoted 2 lines
I don't see issues with this approach. Cc'd Jarkko and Andy just in case I missed something.
I failed to see the
i2c_acpi_get_irq()in the current code. What kernel version do you use?
Can we see the changes against vanilla / i2c-next?
It's added by the first patch in the chain:
https://lkml.org/lkml/2019/5/20/281
I could resend the series with you and Jarkko on CC if that would be better.
Thanks,
Charles
Re: [PATCH 3/5] i2c: core: Move ACPI IRQ handling to probe time
Quoted 16 lines · Charles Keepax
Quoted 7 lines · Andy Shevchenko
Quoted 6 lines · Mika Westerberg
Quoted 4 lines · 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.
Quoted 7 lines
Quoted 2 lines
I don't see issues with this approach. Cc'd Jarkko and Andy just in case I missed something.
I failed to see the
i2c_acpi_get_irq()in the current code. What kernel version do you use?
Can we see the changes against vanilla / i2c-next?
Quoted 6 lines
It's added by the first patch in the chain:
https://lkml.org/lkml/2019/5/20/281
I could resend the series with you and Jarkko on CC if that would be better.
That would be better.
Signature · 2 lines
With Best Regards, Andy Shevchenko
PATCH 4/5 i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
In reply to Charles KeepaxIt makes sense to contain all the ACPI IRQ handling in a single helper function.
---
Note that this one is somewhat interesting, it seems the search through the resource list is done against the companion device of the adapter but the GPIO search is done against the companion device of the client. It feels to me like these really should be done on the same device, and certainly this is what SPI does (both against the equivalent of the adapter). Perhaps someone with more ACPI knowledge than myself could comment?
Thanks,
Charles
drivers/i2c/i2c-core-acpi.c | 3 +++ drivers/i2c/i2c-core-base.c | 4 ---- 2 files changed, 3 insertions(+), 4 deletions(-)
drivers/i2c/i2c-core-acpi.c +3 -0
@@ -164,6 +164,9 @@ int i2c_acpi_get_irq(struct i2c_client *client, int *irq)acpi_dev_free_resource_list (&resource_list); +if (*irq <0 ) + *irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (&client->dev),0 ); +return 0 ; }
drivers/i2c/i2c-core-base.c +0 -4
@@ -336,10 +336,6 @@ static int i2c_device_probe(struct device *dev) irq =of_irq_get (dev->of_node,0 ); }else if (ACPI_COMPANION (dev)) {i2c_acpi_get_irq (client, &irq); - -if (irq == -ENOENT ) - irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (dev), -0 ); }if (irq == -EPROBE_DEFER )return irq;
Signature · 1 line
2.11.0
Re: [PATCH 4/5] i2c: core: Move ACPI gpio IRQ handling into i2c_acpi_get_irq
Quoted 6 lines · Charles Keepax
It makes sense to contain all the ACPI IRQ handling in a single helper function.
Signed-off-by Charles Keepax <[email protected]>---
Quoted 7 lines
Note that this one is somewhat interesting, it seems the search through the resource list is done against the companion device of the adapter but the GPIO search is done against the companion device of the client. It feels to me like these really should be done on the same device, and certainly this is what SPI does (both against the equivalent of the adapter). Perhaps someone with more ACPI knowledge than myself could comment?
What GPIO search you mean? I did not find any ACPI specific GPIO lookup in the i2c-core-acpi/base files.
drivers/i2c/i2c-core-acpi.c int i2c_acpi_get_irq(struct i2c_client *client, int *irq)
Quoted 12 lines
Thanks,
Charlesdrivers/i2c/i2c-core-acpi.c | 3 +++ drivers/i2c/i2c-core-base.c | 4 ---- 2 files changed, 3 insertions(+), 4 deletions(-)drivers/i2c/i2c-core-acpi.c +0
-0@@ -164,6 +164,9 @@ int i2c_acpi_get_irq(struct i2c_client *client, int *irq)
Maybe worth adding kernel-doc explaining what the function does if it does not have already.
Quoted 14 lines
drivers/i2c/i2c-core-acpi.c +3
-0acpi_dev_free_resource_list (&resource_list); +if (*irq <0 ) + *irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (&client->dev),0 ); +return 0 ; }drivers/i2c/i2c-core-base.c +0
-0
drivers/i2c/i2c-core-base.c static int i2c_device_probe(struct device *dev) · line 338
Quoted 3 lines
drivers/i2c/i2c-core-base.c +0
-0@@ -336,10 +336,6 @@ static int i2c_device_probe(struct device *dev) irq =of_irq_get (dev->of_node,0 ); }else if (ACPI_COMPANION (dev)) {i2c_acpi_get_irq (client, &irq);
I think we should check and handle possible error here.
Quoted 9 lines
drivers/i2c/i2c-core-base.c +0
-4- -if (irq == -ENOENT ) - irq =acpi_dev_gpio_irq_get (ACPI_COMPANION (dev), -0 ); }if (irq == -EPROBE_DEFER )return irq;Signature · 1 line
2.11.0
PATCH 5/5 i2c: core: Tidy up handling of init_irq
In reply to Charles KeepaxOnly set init_irq during i2c_device_new and only handle client->irq on the probe/remove paths.
--- drivers/i2c/i2c-core-base.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
drivers/i2c/i2c-core-base.c +3 -2
@@ -322,6 +322,8 @@ 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 ;
@@ -432,7 +434,7 @@ 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);
@@ -749,7 +751,6 @@ i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *infif (!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));
Signature · 1 line
2.11.0