[PATCH] iommu/msm: Use helper function devm_clk_get_prepared()

Zhang Heng
2025-01-03T11:31:28Z

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>
---
drivers/iommu/msm_iommu.c | 51 +++++++++------------------------------
1 file changed, 11 insertions(+), 40 deletions(-)

diff --git a/drivers/iommu/msm_iommu.c b/drivers/iommu/msm_iommu.c
index ce40f0a419ea..2769e4544038 100644
--- a/drivers/iommu/msm_iommu.c
+++ b/drivers/iommu/msm_iommu.c
@@ -725,47 +725,32 @@ 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))
return dev_err_probe(iommu->dev, PTR_ERR(iommu->pclk),
"could not get smmu_pclk\n");

- ret = clk_prepare(iommu->pclk);
- if (ret)
- return dev_err_probe(iommu->dev, ret,
- "could not prepare smmu_pclk\n");
-
- iommu->clk = devm_clk_get(iommu->dev, "iommu_clk");
- if (IS_ERR(iommu->clk)) {
- clk_unprepare(iommu->pclk);
+ iommu->clk = devm_clk_get_prepared(iommu->dev, "iommu_clk");
+ if (IS_ERR(iommu->clk))
return dev_err_probe(iommu->dev, PTR_ERR(iommu->clk),
"could not get iommu_clk\n");
- }
-
- ret = clk_prepare(iommu->clk);
- if (ret) {
- clk_unprepare(iommu->pclk);
- return dev_err_probe(iommu->dev, ret, "could not prepare iommu_clk\n");
- }

r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
iommu->base = devm_ioremap_resource(iommu->dev, r);
if (IS_ERR(iommu->base)) {
ret = dev_err_probe(iommu->dev, PTR_ERR(iommu->base), "could not get iommu base\n");
- goto fail;
+ return ret;
}
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;

@@ -780,8 +765,7 @@ 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,
@@ -791,7 +775,7 @@ 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);
@@ -800,23 +784,19 @@ 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;
}

ret = iommu_device_register(&iommu->iommu, &msm_iommu_ops, &pdev->dev);
if (ret) {
pr_err("Could not register msm-smmu at %pa\n", &ioaddr);
- goto fail;
+ return ret;
}

pr_info("device mapped at %p, irq %d with %d ctx banks\n",
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[] = {
@@ -824,20 +804,11 @@ static const struct of_device_id msm_iommu_dt_match[] = {
{}
};

-static void msm_iommu_remove(struct platform_device *pdev)
-{
- struct msm_iommu_dev *iommu = platform_get_drvdata(pdev);
-
- clk_unprepare(iommu->clk);
- clk_unprepare(iommu->pclk);
-}
-
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,
};
builtin_platform_driver(msm_iommu_driver);
--
2.45.2