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-rw-r--r--drivers/spi/spi.c58
-rw-r--r--include/linux/spi/spi.h19
2 files changed, 76 insertions, 1 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7566482c052c..05c75f890ace 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2442,6 +2442,49 @@ struct spi_controller *__spi_alloc_controller(struct device *dev,
}
EXPORT_SYMBOL_GPL(__spi_alloc_controller);
+static void devm_spi_release_controller(struct device *dev, void *ctlr)
+{
+ spi_controller_put(*(struct spi_controller **)ctlr);
+}
+
+/**
+ * __devm_spi_alloc_controller - resource-managed __spi_alloc_controller()
+ * @dev: physical device of SPI controller
+ * @size: how much zeroed driver-private data to allocate
+ * @slave: whether to allocate an SPI master (false) or SPI slave (true)
+ * Context: can sleep
+ *
+ * Allocate an SPI controller and automatically release a reference on it
+ * when @dev is unbound from its driver. Drivers are thus relieved from
+ * having to call spi_controller_put().
+ *
+ * The arguments to this function are identical to __spi_alloc_controller().
+ *
+ * Return: the SPI controller structure on success, else NULL.
+ */
+struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
+ unsigned int size,
+ bool slave)
+{
+ struct spi_controller **ptr, *ctlr;
+
+ ptr = devres_alloc(devm_spi_release_controller, sizeof(*ptr),
+ GFP_KERNEL);
+ if (!ptr)
+ return NULL;
+
+ ctlr = __spi_alloc_controller(dev, size, slave);
+ if (ctlr) {
+ *ptr = ctlr;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return ctlr;
+}
+EXPORT_SYMBOL_GPL(__devm_spi_alloc_controller);
+
#ifdef CONFIG_OF
static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
{
@@ -2778,6 +2821,11 @@ int devm_spi_register_controller(struct device *dev,
}
EXPORT_SYMBOL_GPL(devm_spi_register_controller);
+static int devm_spi_match_controller(struct device *dev, void *res, void *ctlr)
+{
+ return *(struct spi_controller **)res == ctlr;
+}
+
static int __unregister(struct device *dev, void *null)
{
spi_unregister_device(to_spi_device(dev));
@@ -2819,7 +2867,15 @@ void spi_unregister_controller(struct spi_controller *ctlr)
list_del(&ctlr->list);
mutex_unlock(&board_lock);
- device_unregister(&ctlr->dev);
+ device_del(&ctlr->dev);
+
+ /* Release the last reference on the controller if its driver
+ * has not yet been converted to devm_spi_alloc_master/slave().
+ */
+ if (!devres_find(ctlr->dev.parent, devm_spi_release_controller,
+ devm_spi_match_controller, ctlr))
+ put_device(&ctlr->dev);
+
/* free bus id */
mutex_lock(&board_lock);
if (found == ctlr)
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 99380c0825db..b390fdac1587 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -734,6 +734,25 @@ static inline struct spi_controller *spi_alloc_slave(struct device *host,
return __spi_alloc_controller(host, size, true);
}
+struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
+ unsigned int size,
+ bool slave);
+
+static inline struct spi_controller *devm_spi_alloc_master(struct device *dev,
+ unsigned int size)
+{
+ return __devm_spi_alloc_controller(dev, size, false);
+}
+
+static inline struct spi_controller *devm_spi_alloc_slave(struct device *dev,
+ unsigned int size)
+{
+ if (!IS_ENABLED(CONFIG_SPI_SLAVE))
+ return NULL;
+
+ return __devm_spi_alloc_controller(dev, size, true);
+}
+
extern int spi_register_controller(struct spi_controller *ctlr);
extern int devm_spi_register_controller(struct device *dev,
struct spi_controller *ctlr);