[PATCH v2 1/1] spi: Introduce spi_get_device_match_data() helper

[Andy Shevchenko]

The proposed spi_get_device_match_data() helper is for retrieving
a driver data associated with the ID in an ID table. First, it tries
to get driver data of the device enumerated by firmware interface
(usually Device Tree or ACPI). If none is found it falls back to
the SPI ID table matching.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
v2: rebased on top of v6.1-rc1, so shouldn't be any compilation errors
 drivers/spi/spi.c       | 12 ++++++++++++
 include/linux/spi/spi.h |  3 +++
 2 files changed, 15 insertions(+)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 5f9aedd1f0b6..aaf07052fd01 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -360,6 +360,18 @@ const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev)
 }
 EXPORT_SYMBOL_GPL(spi_get_device_id);
 
+const void *spi_get_device_match_data(const struct spi_device *sdev)
+{
+	const void *match;
+
+	match = device_get_match_data(&sdev->dev);
+	if (match)
+		return match;
+
+	return (const void *)spi_get_device_id(sdev)->driver_data;
+}
+EXPORT_SYMBOL_GPL(spi_get_device_match_data);
+
 static int spi_match_device(struct device *dev, struct device_driver *drv)
 {
 	const struct spi_device	*spi = to_spi_device(dev);
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index fbf8c0d95968..8fe3d0a9d2c9 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -1514,6 +1514,9 @@ extern void spi_unregister_device(struct spi_device *spi);
 extern const struct spi_device_id *
 spi_get_device_id(const struct spi_device *sdev);
 
+extern const void *
+spi_get_device_match_data(const struct spi_device *sdev);
+
 static inline bool
 spi_transfer_is_last(struct spi_controller *ctlr, struct spi_transfer *xfer)
 {
-- 
2.35.1