[PATCH v2 3/7] firmware: samsung: acpm: Add devm_acpm_get_by_phandle helper

[Tudor Ambarus <tudor.ambarus@linaro.org>]

Introduce devm_acpm_get_by_phandle() to standardize how consumer
drivers acquire a handle to the ACPM IPC interface. Enforce the
use of the "samsung,acpm-ipc" property name across the SoC and
simplify the boilerplate code in client drivers.

Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
---
 drivers/firmware/samsung/exynos-acpm.c             | 23 ++++++++++++++++++++++
 .../linux/firmware/samsung/exynos-acpm-protocol.h  |  6 ++++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/firmware/samsung/exynos-acpm.c b/drivers/firmware/samsung/exynos-acpm.c
index cc045370f4b0dc6ccea99e3c2d6f86a43b2e9671..cf849ba23f09d8b1e7f91734a0a1cc064f7407c7 100644
--- a/drivers/firmware/samsung/exynos-acpm.c
+++ b/drivers/firmware/samsung/exynos-acpm.c
@@ -776,6 +776,29 @@ const struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 }
 EXPORT_SYMBOL_GPL(devm_acpm_get_by_node);
 
+/**
+ * devm_acpm_get_by_phandle - Resource managed lookup of the standardized
+ * "samsung,acpm-ipc" handle.
+ * @dev: consumer device
+ *
+ * Returns a pointer to the acpm_handle on success, or an ERR_PTR on failure.
+ */
+const struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev)
+{
+	const struct acpm_handle *handle;
+	struct device_node *np;
+
+	np = of_parse_phandle(dev->of_node, "samsung,acpm-ipc", 0);
+	if (!np)
+		return ERR_PTR(-ENODEV);
+
+	handle = devm_acpm_get_by_node(dev, np);
+	of_node_put(np);
+
+	return handle;
+}
+EXPORT_SYMBOL_GPL(devm_acpm_get_by_phandle);
+
 static const struct acpm_match_data acpm_gs101 = {
 	.initdata_base = ACPM_GS101_INITDATA_BASE,
 	.acpm_clk_dev_name = "gs101-acpm-clk",
diff --git a/include/linux/firmware/samsung/exynos-acpm-protocol.h b/include/linux/firmware/samsung/exynos-acpm-protocol.h
index 43d41e11ad2eb985e27a918ce3f9e9ac15a194ee..9485cdc1d91e86f9a9a8fc00722f3313e3000c6a 100644
--- a/include/linux/firmware/samsung/exynos-acpm-protocol.h
+++ b/include/linux/firmware/samsung/exynos-acpm-protocol.h
@@ -82,6 +82,7 @@ struct device;
 #if IS_ENABLED(CONFIG_EXYNOS_ACPM_PROTOCOL)
 const struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
 						struct device_node *np);
+const struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev);
 #else
 
 static inline const struct acpm_handle *devm_acpm_get_by_node(struct device *dev,
@@ -89,6 +90,11 @@ static inline const struct acpm_handle *devm_acpm_get_by_node(struct device *dev
 {
 	return NULL;
 }
+
+static inline const struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev)
+{
+	return NULL;
+}
 #endif
 
 #endif /* __EXYNOS_ACPM_PROTOCOL_H */

-- 
2.52.0.457.g6b5491de43-goog