// SPDX-License-Identifier: GPL-2.0+
/*
* Samsung Exynos USB HOST EHCI Controller
*
* Copyright (C) 2011 Samsung Electronics Co.Ltd
* Author: Jingoo Han <[email protected]>
* Author: Joonyoung Shim <[email protected]>
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include "ehci.h"
#define DRIVER_DESC "EHCI Exynos driver"
#define EHCI_INSNREG00(base) (base + 0x90)
#define EHCI_INSNREG00_ENA_INCR16 (0x1 << 25)
#define EHCI_INSNREG00_ENA_INCR8 (0x1 << 24)
#define EHCI_INSNREG00_ENA_INCR4 (0x1 << 23)
#define EHCI_INSNREG00_ENA_INCRX_ALIGN (0x1 << 22)
#define EHCI_INSNREG00_ENABLE_DMA_BURST \
(EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 | \
EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN)
static struct hc_driver __read_mostly exynos_ehci_hc_driver;
#define PHY_NUMBER 3
struct exynos_ehci_hcd {
struct clk *clk;
struct device_node *of_node;
struct phy *phy[PHY_NUMBER];
bool legacy_phy;
};
#define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
static int exynos_ehci_get_phy(struct device *dev,
struct exynos_ehci_hcd *exynos_ehci)
{
struct phy *phy;
int phy_number, num_phys;
int ret;
/* Get PHYs for the controller */
num_phys = of_count_phandle_with_args(dev->of_node, "phys",
"#phy-cells");
for (phy_number = 0; phy_number < num_phys; phy_number++) {
phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
if (IS_ERR(phy))
return PTR_ERR(phy);
exynos_ehci->phy[phy_number] = phy;
}
if (num_phys > 0)
return 0;
/* Get PHYs using legacy bindings */
for_each_available_child_of_node_scoped(dev->of_node, child) {
ret = of_property_read_u32(child, "reg", &phy_number);
if (ret) {
dev_err(dev, "Failed to parse device tree\n");
return ret;
}
if (phy_number >= PHY_NUMBER) {
dev_err(dev, "Invalid number of PHYs\n");
return -EINVAL;
}
phy = devm_of_phy_optional_get(dev, child, NULL);
exynos_ehci->phy[phy_number] = phy;
if (IS_ERR(phy))
return PTR_ERR(phy);
}
exynos_ehci->legacy_phy = true;
return 0;
}
static int exynos_ehci_phy_enable(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
int i;
int ret = 0;
for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
ret = phy_power_on(exynos_ehci->phy[i]);
if (ret)
for (i--; i >= 0; i--)
phy_power_off(exynos_ehci->phy[i]);
return ret;
}
static void exynos_ehci_phy_disable(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
int i;
for (i = 0; i < PHY_NUMBER; i++)
phy_power_off(exynos_ehci->phy[i]);
}
static void exynos_setup_vbus_gpio(struct device *dev)
{
struct gpio_desc *gpio;
int err;
gpio = devm_gpiod_get_optional(dev, "samsung,vbus", GPIOD_OUT_HIGH);
err = PTR_ERR_OR_ZERO(gpio);
if (err)
dev_err(dev, "can't request ehci vbus gpio: %d\n", err);
}
static int exynos_ehci_probe(struct platform_device *pdev)
{
struct exynos_ehci_hcd *exynos_ehci;
struct usb_hcd *hcd;
struct ehci_hcd *ehci;
struct resource *res;
int irq;
int err;
/*
* Right now device-tree probed devices don't get dma_mask set.
* Since shared usb code relies on it, set it here for now.
* Once we move to full device tree support this will vanish off.
*/
err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
if (err)
return err;
exynos_setup_vbus_gpio(&pdev->dev);
hcd = usb_create_hcd(&exynos_ehci_hc_driver,
&pdev->dev, dev_name(&pdev->dev));
if (!hcd) {
dev_err(&pdev->dev, "Unable to create HCD\n");
return -ENOMEM;
}
exynos_ehci = to_exynos_ehci(hcd);
err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
if (err)
goto fail_io;
exynos_ehci->clk = devm_clk_get_enabled(&pdev->dev, "usbhost");
if (IS_ERR(exynos_ehci->clk)) {
dev_err(&pdev->dev, "Failed to get usbhost clock\n");
err = PTR_ERR(exynos_ehci->clk);
goto fail_io;
}
hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(hcd->regs)) {
err = PTR_ERR(hcd->regs);
goto fail_io;
}
hcd->rsrc_start = res->start;
hcd->rsrc_len = resource_size(res);
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
err = irq;
goto fail_io;
}
err = exynos_ehci_phy_enable(&pdev->dev);
if (err) {
dev_err(&pdev->dev, "Failed to enable USB phy\n");
goto fail_io;
}
ehci = hcd_to_ehci(hcd);
ehci->caps = hcd->regs;
/*
* Workaround: reset of_node pointer to avoid conflict between legacy
* Exynos EHCI port subnodes and generic USB device bindings
*/
exynos_ehci->of_node = pdev->dev.of_node;
if (exynos_ehci->legacy_phy)
pdev->dev.of_node = NULL;
/* DMA burst Enable */
writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
err = usb_add_hcd(hcd, irq, IRQF_SHARED);
if (err) {
dev_err(&pdev->dev, "Failed to add USB HCD\n");
goto fail_add_hcd;
}
device_wakeup_enable(hcd->self.controller);
platform_set_drvdata(pdev, hcd);
return 0;
fail_add_hcd:
exynos_ehci_phy_disable(&pdev->dev);
pdev->dev.of_node = exynos_ehci->of_node;
fail_io:
usb_put_hcd(hcd);
return err;
}
static void exynos_ehci_remove(struct platform_device *pdev)
{
struct usb_hcd *hcd = platform_get_drvdata(pdev);
struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
pdev->dev.of_node = exynos_ehci->of_node;
usb_remove_hcd(hcd);
exynos_ehci_phy_disable(&pdev->dev);
usb_put_hcd(hcd);
}
static int exynos_ehci_suspend(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
bool do_wakeup = device_may_wakeup(dev);
int rc;
rc = ehci_suspend(hcd, do_wakeup);
if (rc)
return rc;
exynos_ehci_phy_disable(dev);
clk_disable_unprepare(exynos_ehci->clk);
return rc;
}
static int exynos_ehci_resume(struct device *dev)
{
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
int ret;
ret = clk_prepare_enable(exynos_ehci->clk);
if (ret)
return ret;
ret = exynos_ehci_phy_enable(dev);
if (ret) {
dev_err(dev, "Failed to enable USB phy\n");
clk_disable_unprepare(exynos_ehci->clk);
return ret;
}
/* DMA burst Enable */
writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
ehci_resume(hcd, false);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(exynos_ehci_pm_ops,
exynos_ehci_suspend, exynos_ehci_resume);
#ifdef CONFIG_OF
static const struct of_device_id exynos_ehci_match[] = {
{ .compatible = "samsung,exynos4210-ehci" },
{},
};
MODULE_DEVICE_TABLE(of, exynos_ehci_match);
#endif
static struct platform_driver exynos_ehci_driver = {
.probe = exynos_ehci_probe,
.remove_new = exynos_ehci_remove,
.shutdown = usb_hcd_platform_shutdown,
.driver = {
.name = "exynos-ehci",
.pm = pm_ptr(&exynos_ehci_pm_ops),
.of_match_table = of_match_ptr(exynos_ehci_match),
}
};
static const struct ehci_driver_overrides exynos_overrides __initconst = {
.extra_priv_size = sizeof(struct exynos_ehci_hcd),
};
static int __init ehci_exynos_init(void)
{
if (usb_disabled())
return -ENODEV;
ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
return platform_driver_register(&exynos_ehci_driver);
}
module_init(ehci_exynos_init);
static void __exit ehci_exynos_cleanup(void)
{
platform_driver_unregister(&exynos_ehci_driver);
}
module_exit(ehci_exynos_cleanup);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_ALIAS("platform:exynos-ehci");
MODULE_AUTHOR("Jingoo Han");
MODULE_AUTHOR("Joonyoung Shim");
MODULE_LICENSE("GPL v2");
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