[PATCH 5.10.y 1/2] iommu/msm: Use helper function devm_clk_get_prepared()

[Sasha Levin <sashal@kernel.org>]

From: Zhang Heng <zhangheng@kylinos.cn>

[ Upstream commit afc0cbc6e25b37dc9ba11d415ea6858902a7f04b ]

Since commit 7ef9651e9792 ("clk: Provide new devm_clk helpers for prepared
and enabled clocks"), devm_clk_get() and clk_prepare() can now be replaced
by devm_clk_get_prepared() when driver prepares the clocks for the whole
lifetime of the device. Moreover, it is no longer necessary to unprepare
the clocks explicitly.

Signed-off-by: Zhang Heng <zhangheng@kylinos.cn>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20250103113059.463033-1-zhangheng@kylinos.cn
Signed-off-by: Joerg Roedel <jroedel@suse.de>

[5.15 dependency adaptation]
Retain this branch's dev_err() diagnostics, bus_set_iommu() call and
subsys_initcall() registration. Convert both clocks to the already
available devm_clk_get_prepared() helper, return directly from probe
failures, and remove the obsolete int-returning remove callback and
manual clk_unprepare() calls. No new functions are introduced.

This preserves the managed clock cleanup required by the registration
failure unwind in 535a200220ca2c83bc8bf54bd2cbe045d6ee70c4. That target
applies cleanly with a three-way merge while retaining the stable bus
registration.

Stable-dep-of: 535a200220ca ("iommu/msm: Unwind probe state on registration failure")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iommu/msm_iommu.c | 52 ++++++++-------------------------------
 1 file changed, 10 insertions(+), 42 deletions(-)

diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index 149f2e53b39d4..5c83cebbf49a7 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -712,51 +712,34 @@ static int msm_iommu_probe(struct platform_device *pdev)
 	iommu->dev = &pdev->dev;
 	INIT_LIST_HEAD(&iommu->ctx_list);
 
-	iommu->pclk = devm_clk_get(iommu->dev, "smmu_pclk");
+	iommu->pclk = devm_clk_get_prepared(iommu->dev, "smmu_pclk");
 	if (IS_ERR(iommu->pclk)) {
 		dev_err(iommu->dev, "could not get smmu_pclk\n");
 		return PTR_ERR(iommu->pclk);
 	}
 
-	ret = clk_prepare(iommu->pclk);
-	if (ret) {
-		dev_err(iommu->dev, "could not prepare smmu_pclk\n");
-		return ret;
-	}
-
-	iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
+	iommu->clk = devm_clk_get_prepared(iommu->dev, "iommu_clk");
 	if (IS_ERR(iommu->clk)) {
 		dev_err(iommu->dev, "could not get iommu_clk\n");
-		clk_unprepare(iommu->pclk);
 		return PTR_ERR(iommu->clk);
 	}
 
-	ret = clk_prepare(iommu->clk);
-	if (ret) {
-		dev_err(iommu->dev, "could not prepare iommu_clk\n");
-		clk_unprepare(iommu->pclk);
-		return ret;
-	}
-
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	iommu->base = devm_ioremap_resource(iommu->dev, r);
 	if (IS_ERR(iommu->base)) {
 		dev_err(iommu->dev, "could not get iommu base\n");
-		ret = PTR_ERR(iommu->base);
-		goto fail;
+		return PTR_ERR(iommu->base);
 	}
 	ioaddr = r->start;
 
 	iommu->irq = platform_get_irq(pdev, 0);
-	if (iommu->irq < 0) {
-		ret = -ENODEV;
-		goto fail;
-	}
+	if (iommu->irq < 0)
+		return -ENODEV;
 
 	ret = of_property_read_u32(iommu->dev->of_node, "qcom,ncb", &val);
 	if (ret) {
 		dev_err(iommu->dev, "could not get ncb\n");
-		goto fail;
+		return ret;
 	}
 	iommu->ncb = val;
 
@@ -771,8 +754,7 @@ static int msm_iommu_probe(struct platform_device *pdev)
 
 	if (!par) {
 		pr_err("Invalid PAR value detected\n");
-		ret = -ENODEV;
-		goto fail;
+		return -ENODEV;
 	}
 
 	ret = devm_request_threaded_irq(iommu->dev, iommu->irq, NULL,
@@ -782,7 +764,7 @@ static int msm_iommu_probe(struct platform_device *pdev)
 					iommu);
 	if (ret) {
 		pr_err("Request IRQ %d failed with ret=%d\n", iommu->irq, ret);
-		goto fail;
+		return ret;
 	}
 
 	list_add(&iommu->dev_node, &qcom_iommu_devices);
@@ -791,7 +773,7 @@ static int msm_iommu_probe(struct platform_device *pdev)
 				     "msm-smmu.%pa", &ioaddr);
 	if (ret) {
 		pr_err("Could not add msm-smmu at %pa to sysfs\n", &ioaddr);
-		goto fail;
+		return ret;
 	}
 
 	iommu_device_set_ops(&iommu->iommu, &msm_iommu_ops);
@@ -800,7 +782,7 @@ static int msm_iommu_probe(struct platform_device *pdev)
 	ret = iommu_device_register(&iommu->iommu);
 	if (ret) {
 		pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
-		goto fail;
+		return ret;
 	}
 
 	bus_set_iommu(&platform_bus_type, &msm_iommu_ops);
@@ -809,10 +791,6 @@ static int msm_iommu_probe(struct platform_device *pdev)
 		iommu->base, iommu->irq, iommu->ncb);
 
 	return ret;
-fail:
-	clk_unprepare(iommu->clk);
-	clk_unprepare(iommu->pclk);
-	return ret;
 }
 
 static const struct of_device_id msm_iommu_dt_match[] = {
@@ -820,22 +798,12 @@ static const struct of_device_id msm_iommu_dt_match[] = {
 	{}
 };
 
-static int msm_iommu_remove(struct platform_device *pdev)
-{
-	struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
-
-	clk_unprepare(iommu->clk);
-	clk_unprepare(iommu->pclk);
-	return 0;
-}
-
 static struct platform_driver msm_iommu_driver = {
 	.driver = {
 		.name	= "msm_iommu",
 		.of_match_table = msm_iommu_dt_match,
 	},
 	.probe		= msm_iommu_probe,
-	.remove		= msm_iommu_remove,
 };
 
 static int __init msm_iommu_driver_init(void)
-- 
2.53.0