[PATCH 1/2] scsi: ufs: ufs-qcom: add basic interconnect support

[Brian Masney]

The firmware on the Qualcomm platforms expects the interconnect votes to
be present. Let's add very basic support where the maximum throughput is
requested to match what's done in a few other drivers.

This will not break boot on systems where the interconnects and
interconnect-names properties are not specified in device tree for UFS
since the interconnect framework will silently return.

Signed-off-by: Brian Masney <bmasney@xxxxxxxxxx>
---
 drivers/ufs/host/ufs-qcom.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index 8ad1415e10b6..55bf8dd88985 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -7,6 +7,7 @@
 #include <linux/time.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
+#include <linux/interconnect.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -936,6 +937,22 @@ static const struct reset_control_ops ufs_qcom_reset_ops = {
 	.deassert = ufs_qcom_reset_deassert,
 };
 
+static int ufs_qcom_icc_init(struct device *dev, char *pathname)
+{
+	struct icc_path *path;
+	int ret;
+
+	path = devm_of_icc_get(dev, pathname);
+	if (IS_ERR(path))
+		return dev_err_probe(dev, PTR_ERR(path), "failed to acquire interconnect path\n");
+
+	ret = icc_set_bw(path, 0, UINT_MAX);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "failed to set bandwidth request\n");
+
+	return 0;
+}
+
 /**
  * ufs_qcom_init - bind phy with controller
  * @hba: host controller instance
@@ -991,6 +1008,14 @@ static int ufs_qcom_init(struct ufs_hba *hba)
 			err = dev_err_probe(dev, PTR_ERR(host->generic_phy), "Failed to get PHY\n");
 			goto out_variant_clear;
 		}
+
+		err = ufs_qcom_icc_init(dev, "ufs-ddr");
+		if (err)
+			goto out_variant_clear;
+
+		err = ufs_qcom_icc_init(dev, "cpu-ufs");
+		if (err)
+			goto out_variant_clear;
 	}
 
 	host->device_reset = devm_gpiod_get_optional(dev, "reset",
-- 
2.38.1