https://github.com/torvalds/linux
Tip revision: e0dccc3b76fb35bb257b4118367a883073d7390e authored by Linus Torvalds on 24 July 2022, 20:26:27 UTC
Linux 5.19-rc8
Linux 5.19-rc8
Tip revision: e0dccc3
platform.c
// SPDX-License-Identifier: GPL-2.0
/*
* Platform driver for the Synopsys DesignWare DMA Controller
*
* Copyright (C) 2007-2008 Atmel Corporation
* Copyright (C) 2010-2011 ST Microelectronics
* Copyright (C) 2013 Intel Corporation
*
* Some parts of this driver are derived from the original dw_dmac.
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
#include <linux/platform_device.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/of.h>
#include <linux/acpi.h>
#include "internal.h"
#define DRV_NAME "dw_dmac"
static int dw_probe(struct platform_device *pdev)
{
const struct dw_dma_chip_pdata *match;
struct dw_dma_chip_pdata *data;
struct dw_dma_chip *chip;
struct device *dev = &pdev->dev;
int err;
match = device_get_match_data(dev);
if (!match)
return -ENODEV;
data = devm_kmemdup(&pdev->dev, match, sizeof(*match), GFP_KERNEL);
if (!data)
return -ENOMEM;
chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->irq = platform_get_irq(pdev, 0);
if (chip->irq < 0)
return chip->irq;
chip->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(chip->regs))
return PTR_ERR(chip->regs);
err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
if (err)
return err;
if (!data->pdata)
data->pdata = dev_get_platdata(dev);
if (!data->pdata)
data->pdata = dw_dma_parse_dt(pdev);
chip->dev = dev;
chip->id = pdev->id;
chip->pdata = data->pdata;
data->chip = chip;
chip->clk = devm_clk_get_optional(chip->dev, "hclk");
if (IS_ERR(chip->clk))
return PTR_ERR(chip->clk);
err = clk_prepare_enable(chip->clk);
if (err)
return err;
pm_runtime_enable(&pdev->dev);
err = data->probe(chip);
if (err)
goto err_dw_dma_probe;
platform_set_drvdata(pdev, data);
dw_dma_of_controller_register(chip->dw);
dw_dma_acpi_controller_register(chip->dw);
return 0;
err_dw_dma_probe:
pm_runtime_disable(&pdev->dev);
clk_disable_unprepare(chip->clk);
return err;
}
static int dw_remove(struct platform_device *pdev)
{
struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
struct dw_dma_chip *chip = data->chip;
int ret;
dw_dma_acpi_controller_free(chip->dw);
dw_dma_of_controller_free(chip->dw);
ret = data->remove(chip);
if (ret)
dev_warn(chip->dev, "can't remove device properly: %d\n", ret);
pm_runtime_disable(&pdev->dev);
clk_disable_unprepare(chip->clk);
return 0;
}
static void dw_shutdown(struct platform_device *pdev)
{
struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
struct dw_dma_chip *chip = data->chip;
/*
* We have to call do_dw_dma_disable() to stop any ongoing transfer. On
* some platforms we can't do that since DMA device is powered off.
* Moreover we have no possibility to check if the platform is affected
* or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
* unconditionally. On the other hand we can't use
* pm_runtime_suspended() because runtime PM framework is not fully
* used by the driver.
*/
pm_runtime_get_sync(chip->dev);
do_dw_dma_disable(chip);
pm_runtime_put_sync_suspend(chip->dev);
clk_disable_unprepare(chip->clk);
}
#ifdef CONFIG_OF
static const struct of_device_id dw_dma_of_id_table[] = {
{ .compatible = "snps,dma-spear1340", .data = &dw_dma_chip_pdata },
{ .compatible = "renesas,rzn1-dma", .data = &dw_dma_chip_pdata },
{}
};
MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
#endif
#ifdef CONFIG_ACPI
static const struct acpi_device_id dw_dma_acpi_id_table[] = {
{ "INTL9C60", (kernel_ulong_t)&dw_dma_chip_pdata },
{ "80862286", (kernel_ulong_t)&dw_dma_chip_pdata },
{ "808622C0", (kernel_ulong_t)&dw_dma_chip_pdata },
/* Elkhart Lake iDMA 32-bit (PSE DMA) */
{ "80864BB4", (kernel_ulong_t)&xbar_chip_pdata },
{ "80864BB5", (kernel_ulong_t)&xbar_chip_pdata },
{ "80864BB6", (kernel_ulong_t)&xbar_chip_pdata },
{ }
};
MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
#endif
#ifdef CONFIG_PM_SLEEP
static int dw_suspend_late(struct device *dev)
{
struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
struct dw_dma_chip *chip = data->chip;
do_dw_dma_disable(chip);
clk_disable_unprepare(chip->clk);
return 0;
}
static int dw_resume_early(struct device *dev)
{
struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
struct dw_dma_chip *chip = data->chip;
int ret;
ret = clk_prepare_enable(chip->clk);
if (ret)
return ret;
return do_dw_dma_enable(chip);
}
#endif /* CONFIG_PM_SLEEP */
static const struct dev_pm_ops dw_dev_pm_ops = {
SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
};
static struct platform_driver dw_driver = {
.probe = dw_probe,
.remove = dw_remove,
.shutdown = dw_shutdown,
.driver = {
.name = DRV_NAME,
.pm = &dw_dev_pm_ops,
.of_match_table = of_match_ptr(dw_dma_of_id_table),
.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
},
};
static int __init dw_init(void)
{
return platform_driver_register(&dw_driver);
}
subsys_initcall(dw_init);
static void __exit dw_exit(void)
{
platform_driver_unregister(&dw_driver);
}
module_exit(dw_exit);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
MODULE_ALIAS("platform:" DRV_NAME);