kernel/drivers/phy/broadcom/phy-bcm-kona-usb2.c
2024-07-22 17:22:30 +08:00

146 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
*
* Copyright (C) 2013 Linaro Limited
* Matt Porter <mporter@linaro.org>
*/
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#define OTGCTL (0)
#define OTGCTL_OTGSTAT2 BIT(31)
#define OTGCTL_OTGSTAT1 BIT(30)
#define OTGCTL_PRST_N_SW BIT(11)
#define OTGCTL_HRESET_N BIT(10)
#define OTGCTL_UTMI_LINE_STATE1 BIT(9)
#define OTGCTL_UTMI_LINE_STATE0 BIT(8)
#define P1CTL (8)
#define P1CTL_SOFT_RESET BIT(1)
#define P1CTL_NON_DRIVING BIT(0)
struct bcm_kona_usb {
void __iomem *regs;
};
static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
{
u32 val;
val = readl(phy->regs + OTGCTL);
if (on) {
/* Configure and power PHY */
val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
} else {
val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
}
writel(val, phy->regs + OTGCTL);
}
static int bcm_kona_usb_phy_init(struct phy *gphy)
{
struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
u32 val;
/* Soft reset PHY */
val = readl(phy->regs + P1CTL);
val &= ~P1CTL_NON_DRIVING;
val |= P1CTL_SOFT_RESET;
writel(val, phy->regs + P1CTL);
writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
/* Reset needs to be asserted for 2ms */
mdelay(2);
writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
return 0;
}
static int bcm_kona_usb_phy_power_on(struct phy *gphy)
{
struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
bcm_kona_usb_phy_power(phy, 1);
return 0;
}
static int bcm_kona_usb_phy_power_off(struct phy *gphy)
{
struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
bcm_kona_usb_phy_power(phy, 0);
return 0;
}
static const struct phy_ops ops = {
.init = bcm_kona_usb_phy_init,
.power_on = bcm_kona_usb_phy_power_on,
.power_off = bcm_kona_usb_phy_power_off,
.owner = THIS_MODULE,
};
static int bcm_kona_usb2_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct bcm_kona_usb *phy;
struct phy *gphy;
struct phy_provider *phy_provider;
phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
if (!phy)
return -ENOMEM;
phy->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(phy->regs))
return PTR_ERR(phy->regs);
platform_set_drvdata(pdev, phy);
gphy = devm_phy_create(dev, NULL, &ops);
if (IS_ERR(gphy))
return PTR_ERR(gphy);
/* The Kona PHY supports an 8-bit wide UTMI interface */
phy_set_bus_width(gphy, 8);
phy_set_drvdata(gphy, phy);
phy_provider = devm_of_phy_provider_register(dev,
of_phy_simple_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
{ .compatible = "brcm,kona-usb2-phy" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
static struct platform_driver bcm_kona_usb2_driver = {
.probe = bcm_kona_usb2_probe,
.driver = {
.name = "bcm-kona-usb2",
.of_match_table = bcm_kona_usb2_dt_ids,
},
};
module_platform_driver(bcm_kona_usb2_driver);
MODULE_ALIAS("platform:bcm-kona-usb2");
MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
MODULE_LICENSE("GPL v2");