On 3/23/24 18:43, Marek Behún wrote:
Add resource managed version of irq_create_mapping(), to help drivers
automatically dispose a linux irq mapping when driver is detached.
The new function devm_irq_create_mapping() is not yet used, but the
action function can be used in the FSL CAAM driver.
Signed-off-by: Marek Behún <kabel@xxxxxxxxxx>
---
drivers/crypto/caam/jr.c | 8 ++----
include/linux/devm-helpers.h | 54 ++++++++++++++++++++++++++++++++++++
2 files changed, 56 insertions(+), 6 deletions(-)
diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c
index 26eba7de3fb0..ad0295b055f8 100644
--- a/drivers/crypto/caam/jr.c
+++ b/drivers/crypto/caam/jr.c
@@ -7,6 +7,7 @@
* Copyright 2019, 2023 NXP
*/
+#include <linux/devm-helpers.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
@@ -576,11 +577,6 @@ static int caam_jr_init(struct device *dev)
return error;
}
-static void caam_jr_irq_dispose_mapping(void *data)
-{
- irq_dispose_mapping((unsigned long)data);
-}
-
/*
* Probe routine for each detected JobR subsystem.
*/
@@ -656,7 +652,7 @@ static int caam_jr_probe(struct platform_device *pdev)
return -EINVAL;
}
- error = devm_add_action_or_reset(jrdev, caam_jr_irq_dispose_mapping,
+ error = devm_add_action_or_reset(jrdev, devm_irq_mapping_drop,
(void *)(unsigned long)jrpriv->irq);
if (error)
return error;
diff --git a/include/linux/devm-helpers.h b/include/linux/devm-helpers.h
index 74891802200d..3805551fd433 100644
--- a/include/linux/devm-helpers.h
+++ b/include/linux/devm-helpers.h
@@ -24,6 +24,8 @@
*/
#include <linux/device.h>
+#include <linux/kconfig.h>
+#include <linux/irqdomain.h>
#include <linux/workqueue.h>
My confidence level is not terribly high today, so I am likely to accept
just about any counter arguments :) But ... More I think of this whole
header, less convinced I am that this (the header) is a great idea. I
wonder who has authored a concept like this... :rolleyes:
Pulling punch of unrelated APIs (or, unrelated except the devm-usage) in
one header has potential to be including a lot of unneeded stuff to the
users. I am under impression this can be bad for example for the build
times.
I think that ideally the devm-APIs should live close to their non-devm
counterparts, and this header should be just used as a last resort, when
all the other options fail :) May I assume all other options have failed
for the IRQ stuff?
Well, I will leave the big picture to the bigger minds. When just
looking at the important things like the function names and coding style
- this change looks Ok to me ;)
static inline void devm_delayed_work_drop(void *res)
@@ -76,4 +78,56 @@ static inline int devm_work_autocancel(struct device *dev,
return devm_add_action(dev, devm_work_drop, w);
}
+/**
+ * devm_irq_mapping_drop - devm action for disposing an irq mapping
+ * @res: linux irq number cast to the void * type
+ *
+ * devm_irq_mapping_drop() can be used as an action parameter for the
+ * devm_add_action_or_reset() function in order to automatically dispose
+ * a linux irq mapping when a device driver is detached.
+ */
+static inline void devm_irq_mapping_drop(void *res)
+{
+ irq_dispose_mapping((unsigned int)(unsigned long)res);
+}
+
+/**
+ * devm_irq_create_mapping - Resource managed version of irq_create_mapping()
+ * @dev: Device which lifetime the mapping is bound to
+ * @domain: domain owning this hardware interrupt or NULL for default domain
+ * @hwirq: hardware irq number in that domain space
+ *
+ * Create an irq mapping to linux irq space which is automatically disposed when
+ * the driver is detached.
+ * devm_irq_create_mapping() can be used to omit the explicit
+ * irq_dispose_mapping() call when driver is detached.
+ *
+ * Returns a linux irq number on success, 0 if mapping could not be created, or
+ * a negative error number if devm action could not be added.
+ */
+static inline int devm_irq_create_mapping(struct device *dev,
+ struct irq_domain *domain,
+ irq_hw_number_t hwirq)
+{
+ unsigned int virq = irq_create_mapping(domain, hwirq);
+
+ if (!virq)
+ return 0;
+
+ /*
+ * irq_dispose_mapping() is an empty function if CONFIG_IRQ_DOMAIN is
+ * disabled. No need to register an action in that case.
+ */
+ if (IS_ENABLED(CONFIG_IRQ_DOMAIN)) {
+ int err;
+
+ err = devm_add_action_or_reset(dev, devm_irq_mapping_drop,
+ (void *)(unsigned long)virq);
+ if (err)
+ return err;
+ }
+
+ return virq;
+}
+
#endif
--
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland
~~ When things go utterly wrong vim users can always type :help! ~~
