[PATCH v3 3/3] spi: acpi: Initialize modalias from of_compatible

[Dan O'Donovan]

From: Crestez Dan Leonard <leonard.crestez@xxxxxxxxx>

When using devicetree spi_device.modalias is set to the compatible
string with the vendor prefix removed. For SPI devices described via
ACPI the spi_device.modalias string is initialized by acpi_device_hid.
When using ACPI and DT ids this string ends up something like "PRP0001".

Change acpi_register_spi_device to use the of_compatible property if
present. This makes it easier to instantiate spi drivers through ACPI
with DT ids.

Signed-off-by: Crestez Dan Leonard <leonard.crestez@xxxxxxxxx>
Signed-off-by: Dan O'Donovan <dan@xxxxxxxxxx>
---
 drivers/spi/spi.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 656dd3e..4b562e8 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1722,13 +1722,21 @@ static acpi_status acpi_register_spi_device(struct spi_master *master,
 		return AE_OK;
 	}
 
+	/*
+	 * Populate modalias from compatible property if available,
+	 * otherwise use native ACPI information
+	 */
+	if ((!adev->data.of_compatible) ||
+	    acpi_of_modalias(adev, spi->modalias, sizeof(spi->modalias)))
+		strlcpy(spi->modalias, acpi_device_hid(adev),
+			sizeof(spi->modalias));
+
 	if (spi->irq < 0)
 		spi->irq = acpi_dev_gpio_irq_get(adev, 0);
 
 	acpi_device_set_enumerated(adev);
 
 	adev->power.flags.ignore_parent = true;
-	strlcpy(spi->modalias, acpi_device_hid(adev), sizeof(spi->modalias));
 	if (spi_add_device(spi)) {
 		adev->power.flags.ignore_parent = false;
 		dev_err(&master->dev, "failed to add SPI device %s from ACPI\n",
-- 
2.7.4