linux_dsm_epyc7002/drivers/bus/tegra-aconnect.c
Sameer Pujar 0d7dab9261 bus: tegra-aconnect: use devm_clk_*() helpers
aconnect bus driver is using pm_clk_*() interface for managing clocks.
With this, clocks seem to be always ON. This happens on Tegra devices
which use BPMP co-processor to manage clock resources, where clocks
are enabled during prepare phase. This is necessary because calls to
BPMP are always blocking. When pm_clk_*() interface is used on such
Tegra devices, clock prepare count is not balanced till driver remove()
gets executed and hence clocks are seen ON always. Thus this patch
replaces pm_clk_*() with devm_clk_*() framework.

Suggested-by: Mohan Kumar D <mkumard@nvidia.com>
Reviewed-by: Jonathan Hunter <jonathanh@nvidia.com>
Signed-off-by: Sameer Pujar <spujar@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-03-28 17:24:57 +01:00

119 lines
2.8 KiB
C

/*
* Tegra ACONNECT Bus Driver
*
* Copyright (C) 2016, NVIDIA CORPORATION. All rights reserved.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
struct tegra_aconnect {
struct clk *ape_clk;
struct clk *apb2ape_clk;
};
static int tegra_aconnect_probe(struct platform_device *pdev)
{
struct tegra_aconnect *aconnect;
if (!pdev->dev.of_node)
return -EINVAL;
aconnect = devm_kzalloc(&pdev->dev, sizeof(struct tegra_aconnect),
GFP_KERNEL);
if (!aconnect)
return -ENOMEM;
aconnect->ape_clk = devm_clk_get(&pdev->dev, "ape");
if (IS_ERR(aconnect->ape_clk)) {
dev_err(&pdev->dev, "Can't retrieve ape clock\n");
return PTR_ERR(aconnect->ape_clk);
}
aconnect->apb2ape_clk = devm_clk_get(&pdev->dev, "apb2ape");
if (IS_ERR(aconnect->apb2ape_clk)) {
dev_err(&pdev->dev, "Can't retrieve apb2ape clock\n");
return PTR_ERR(aconnect->apb2ape_clk);
}
dev_set_drvdata(&pdev->dev, aconnect);
pm_runtime_enable(&pdev->dev);
of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n");
return 0;
}
static int tegra_aconnect_remove(struct platform_device *pdev)
{
pm_runtime_disable(&pdev->dev);
return 0;
}
static int tegra_aconnect_runtime_resume(struct device *dev)
{
struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(aconnect->ape_clk);
if (ret) {
dev_err(dev, "ape clk_enable failed: %d\n", ret);
return ret;
}
ret = clk_prepare_enable(aconnect->apb2ape_clk);
if (ret) {
clk_disable_unprepare(aconnect->ape_clk);
dev_err(dev, "apb2ape clk_enable failed: %d\n", ret);
return ret;
}
return 0;
}
static int tegra_aconnect_runtime_suspend(struct device *dev)
{
struct tegra_aconnect *aconnect = dev_get_drvdata(dev);
clk_disable_unprepare(aconnect->ape_clk);
clk_disable_unprepare(aconnect->apb2ape_clk);
return 0;
}
static const struct dev_pm_ops tegra_aconnect_pm_ops = {
SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend,
tegra_aconnect_runtime_resume, NULL)
};
static const struct of_device_id tegra_aconnect_of_match[] = {
{ .compatible = "nvidia,tegra210-aconnect", },
{ }
};
MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match);
static struct platform_driver tegra_aconnect_driver = {
.probe = tegra_aconnect_probe,
.remove = tegra_aconnect_remove,
.driver = {
.name = "tegra-aconnect",
.of_match_table = tegra_aconnect_of_match,
.pm = &tegra_aconnect_pm_ops,
},
};
module_platform_driver(tegra_aconnect_driver);
MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver");
MODULE_AUTHOR("Jon Hunter <jonathanh@nvidia.com>");
MODULE_LICENSE("GPL v2");