linux-kernel - [PATCH] regmap: irq: add devm apis for regmap_{add,del}_irq

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Date:	Wed, 10 Feb 2016 14:29:50 +0530
From:	Laxman Dewangan <ldewangan@...dia.com>
To:	<broonie@...nel.org>, <gregkh@...uxfoundation.org>
CC:	<linux-kernel@...r.kernel.org>,
	Laxman Dewangan <ldewangan@...dia.com>
Subject: [PATCH] regmap: irq: add devm apis for regmap_{add,del}_irq_chip

Add device managed APIs for regmap_add_irq_chip() and
regmap_del_irq_chip() so that it can be managed by
device framework for freeing it.

This helps on following:
1. Maintaining the sequence of resource allocation and deallocation
	regmap_add_irq_chip(&d);
	devm_requested_threaded_irq(virq)

	On free path:
		regmap_del_irq_chip(d);
		and then removing the irq registration.

	On this case, regmap irq is deleted before the irq is free.
	This force to use normal irq registration.

	By using devm apis, the sequence can be maintain properly:
		devm_regmap_add_irq_chip(&d);
		devm_requested_threaded_irq(virq);

	and resource deallocation will be done in reverse order
	by device framework.

2. No need to delete the regmap_irq_chip in error path or remove
   callback and hence there is less code on this path.

Signed-off-by: Laxman Dewangan <ldewangan@...dia.com>
---
 drivers/base/regmap/regmap-irq.c | 82 ++++++++++++++++++++++++++++++++++++++++
 include/linux/regmap.h           |  8 ++++
 2 files changed, 90 insertions(+)

diff --git a/drivers/base/regmap/regmap-irq.c b/drivers/base/regmap/regmap-irq.c
index 7e1e9e8..36d08ca 100644
--- a/drivers/base/regmap/regmap-irq.c
+++ b/drivers/base/regmap/regmap-irq.c
@@ -695,6 +695,88 @@ void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *d)
 }
 EXPORT_SYMBOL_GPL(regmap_del_irq_chip);
 
+static void devm_regmap_irq_chip_release(struct device *dev, void *res)
+{
+	struct regmap_irq_chip_data *d = *(struct regmap_irq_chip_data **)res;
+
+	regmap_del_irq_chip(d->irq, d);
+}
+
+static int devm_regmap_irq_chip_match(struct device *dev, void *res, void *data)
+
+{
+	struct regmap_irq_chip_data **r = res;
+
+	if (!r || !*r) {
+		WARN_ON(!r || !*r);
+		return 0;
+	}
+	return *r == data;
+}
+
+/**
+ * devm_regmap_add_irq_chip(): Resource manager regmap_add_irq_chip()
+ *
+ * @dev:       The device pointer on which irq_chip belongs to.
+ * @map:       The regmap for the device.
+ * @irq:       The IRQ the device uses to signal interrupts
+ * @irq_flags: The IRQF_ flags to use for the primary interrupt.
+ * @chip:      Configuration for the interrupt controller.
+ * @data:      Runtime data structure for the controller, allocated on success
+ *
+ * Returns 0 on success or an errno on failure.
+ *
+ * The regmap_irq_chip data automatically be released when the device is
+ * unbound.
+ */
+int devm_regmap_add_irq_chip(struct device *dev, struct regmap *map, int irq,
+			     int irq_flags, int irq_base,
+			     const struct regmap_irq_chip *chip,
+			     struct regmap_irq_chip_data **data)
+{
+	struct regmap_irq_chip_data **ptr, *d;
+	int ret;
+
+	ptr = devres_alloc(devm_regmap_irq_chip_release, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return -ENOMEM;
+
+	ret = regmap_add_irq_chip(map, irq, irq_flags, irq_base,
+				  chip, &d);
+	if (ret < 0) {
+		devres_free(ptr);
+		return ret;
+	}
+
+	*ptr = d;
+	devres_add(dev, ptr);
+	*data = d;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_regmap_add_irq_chip);
+
+/**
+ * devm_regmap_del_irq_chip(): Resource managed regmap_del_irq_chip()
+ *
+ * @dev: Device for which which resource was allocated.
+ * @irq: Primary IRQ for the device
+ * @d:   regmap_irq_chip_data allocated by regmap_add_irq_chip()
+ */
+void devm_regmap_del_irq_chip(struct device *dev, int irq,
+			      struct regmap_irq_chip_data *data)
+{
+	int rc;
+
+	WARN_ON(irq != data->irq);
+	rc = devres_release(dev, devm_regmap_irq_chip_release,
+			    devm_regmap_irq_chip_match, data);
+
+	if (rc != 0)
+		WARN_ON(rc);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_del_irq_chip);
+
 /**
  * regmap_irq_chip_get_base(): Retrieve interrupt base for a regmap IRQ chip
  *
diff --git a/include/linux/regmap.h b/include/linux/regmap.h
index 27aaac9..182602b 100644
--- a/include/linux/regmap.h
+++ b/include/linux/regmap.h
@@ -868,6 +868,14 @@ int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 			int irq_base, const struct regmap_irq_chip *chip,
 			struct regmap_irq_chip_data **data);
 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
+
+int devm_regmap_add_irq_chip(struct device *dev, struct regmap *map, int irq,
+			     int irq_flags, int irq_base,
+			     const struct regmap_irq_chip *chip,
+			     struct regmap_irq_chip_data **data);
+void devm_regmap_del_irq_chip(struct device *dev, int irq,
+			      struct regmap_irq_chip_data *data);
+
 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
 struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data);
-- 
2.1.4