scsi: ufs-qcom: Add support for platforms booting ACPI

New Qualcomm AArch64 based laptops are now available which use UFS as their
primary data storage medium.  These devices are supplied with ACPI support
out of the box.  This patch ensures the Qualcomm UFS driver will be bound
when the "QCOM24A5" H/W device is advertised as present.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ufs/ufs-qcom.c

@@ -12,6 +12,7 @@
  *
  */
 
+#include <linux/acpi.h>
 #include <linux/time.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -170,6 +171,9 @@ static int ufs_qcom_init_lane_clks(struct ufs_qcom_host *host)
 	int err = 0;
 	struct device *dev = host->hba->dev;
 
+	if (has_acpi_companion(dev))
+		return 0;
+
 	err = ufs_qcom_host_clk_get(dev, "rx_lane0_sync_clk",
 					&host->rx_l0_sync_clk, false);
 	if (err)
@@ -1136,9 +1140,13 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 			__func__, err);
 		goto out_variant_clear;
 	} else if (IS_ERR(host->generic_phy)) {
-		err = PTR_ERR(host->generic_phy);
-		dev_err(dev, "%s: PHY get failed %d\n", __func__, err);
-		goto out_variant_clear;
+		if (has_acpi_companion(dev)) {
+			host->generic_phy = NULL;
+		} else {
+			err = PTR_ERR(host->generic_phy);
+			dev_err(dev, "%s: PHY get failed %d\n", __func__, err);
+			goto out_variant_clear;
+		}
 	}
 
 	err = ufs_qcom_bus_register(host);
@@ -1608,6 +1616,14 @@ static const struct of_device_id ufs_qcom_of_match[] = {
 };
 MODULE_DEVICE_TABLE(of, ufs_qcom_of_match);
 
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id ufs_qcom_acpi_match[] = {
+	{ "QCOM24A5" },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, ufs_qcom_acpi_match);
+#endif
+
 static const struct dev_pm_ops ufs_qcom_pm_ops = {
 	.suspend	= ufshcd_pltfrm_suspend,
 	.resume		= ufshcd_pltfrm_resume,
@@ -1624,6 +1640,7 @@ static struct platform_driver ufs_qcom_pltform = {
 		.name	= "ufshcd-qcom",
 		.pm	= &ufs_qcom_pm_ops,
 		.of_match_table = of_match_ptr(ufs_qcom_of_match),
+		.acpi_match_table = ACPI_PTR(ufs_qcom_acpi_match),
 	},
 };
 module_platform_driver(ufs_qcom_pltform);