phy-samsung-usb3.c
/* linux/drivers/usb/phy/phy-samsung-usb3.c
*
* Copyright (c) 2013 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* Author: Vivek Gautam <gautam.vivek@samsung.com>
*
* Samsung USB 3.0 PHY transceiver; talks to DWC3 controller.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/usb/samsung_usb_phy.h>
#include <linux/platform_data/samsung-usbphy.h>
#include "phy-samsung-usb.h"
/*
* Sets the phy clk as EXTREFCLK (XXTI) which is internal clock from clock core.
*/
static u32 samsung_usb3phy_set_refclk(struct samsung_usbphy *sphy)
{
u32 reg;
u32 refclk;
refclk = sphy->ref_clk_freq;
reg = PHYCLKRST_REFCLKSEL_EXT_REFCLK |
PHYCLKRST_FSEL(refclk);
switch (refclk) {
case FSEL_CLKSEL_50M:
reg |= (PHYCLKRST_MPLL_MULTIPLIER_50M_REF |
PHYCLKRST_SSC_REFCLKSEL(0x00));
break;
case FSEL_CLKSEL_20M:
reg |= (PHYCLKRST_MPLL_MULTIPLIER_20MHZ_REF |
PHYCLKRST_SSC_REFCLKSEL(0x00));
break;
case FSEL_CLKSEL_19200K:
reg |= (PHYCLKRST_MPLL_MULTIPLIER_19200KHZ_REF |
PHYCLKRST_SSC_REFCLKSEL(0x88));
break;
case FSEL_CLKSEL_24M:
default:
reg |= (PHYCLKRST_MPLL_MULTIPLIER_24MHZ_REF |
PHYCLKRST_SSC_REFCLKSEL(0x88));
break;
}
return reg;
}
static void samsung_exynos5_usb3phy_enable(struct samsung_usbphy *sphy)
{
void __iomem *regs = sphy->regs;
u32 phyparam0;
u32 phyparam1;
u32 linksystem;
u32 phybatchg;
u32 phytest;
u32 phyclkrst;
/* Reset USB 3.0 PHY */
writel(0x0, regs + EXYNOS5_DRD_PHYREG0);
phyparam0 = readl(regs + EXYNOS5_DRD_PHYPARAM0);
/* Select PHY CLK source */
phyparam0 &= ~PHYPARAM0_REF_USE_PAD;
/* Set Loss-of-Signal Detector sensitivity */
phyparam0 &= ~PHYPARAM0_REF_LOSLEVEL_MASK;
phyparam0 |= PHYPARAM0_REF_LOSLEVEL;
writel(phyparam0, regs + EXYNOS5_DRD_PHYPARAM0);
writel(0x0, regs + EXYNOS5_DRD_PHYRESUME);
/*
* Setting the Frame length Adj value[6:1] to default 0x20
* See xHCI 1.0 spec, 5.2.4
*/
linksystem = LINKSYSTEM_XHCI_VERSION_CONTROL |
LINKSYSTEM_FLADJ(0x20);
writel(linksystem, regs + EXYNOS5_DRD_LINKSYSTEM);
phyparam1 = readl(regs + EXYNOS5_DRD_PHYPARAM1);
/* Set Tx De-Emphasis level */
phyparam1 &= ~PHYPARAM1_PCS_TXDEEMPH_MASK;
phyparam1 |= PHYPARAM1_PCS_TXDEEMPH;
writel(phyparam1, regs + EXYNOS5_DRD_PHYPARAM1);
phybatchg = readl(regs + EXYNOS5_DRD_PHYBATCHG);
phybatchg |= PHYBATCHG_UTMI_CLKSEL;
writel(phybatchg, regs + EXYNOS5_DRD_PHYBATCHG);
/* PHYTEST POWERDOWN Control */
phytest = readl(regs + EXYNOS5_DRD_PHYTEST);
phytest &= ~(PHYTEST_POWERDOWN_SSP |
PHYTEST_POWERDOWN_HSP);
writel(phytest, regs + EXYNOS5_DRD_PHYTEST);
/* UTMI Power Control */
writel(PHYUTMI_OTGDISABLE, regs + EXYNOS5_DRD_PHYUTMI);
phyclkrst = samsung_usb3phy_set_refclk(sphy);
phyclkrst |= PHYCLKRST_PORTRESET |
/* Digital power supply in normal operating mode */
PHYCLKRST_RETENABLEN |
/* Enable ref clock for SS function */
PHYCLKRST_REF_SSP_EN |
/* Enable spread spectrum */
PHYCLKRST_SSC_EN |
/* Power down HS Bias and PLL blocks in suspend mode */
PHYCLKRST_COMMONONN;
writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
udelay(10);
phyclkrst &= ~(PHYCLKRST_PORTRESET);
writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
}
static void samsung_exynos5_usb3phy_disable(struct samsung_usbphy *sphy)
{
u32 phyutmi;
u32 phyclkrst;
u32 phytest;
void __iomem *regs = sphy->regs;
phyutmi = PHYUTMI_OTGDISABLE |
PHYUTMI_FORCESUSPEND |
PHYUTMI_FORCESLEEP;
writel(phyutmi, regs + EXYNOS5_DRD_PHYUTMI);
/* Resetting the PHYCLKRST enable bits to reduce leakage current */
phyclkrst = readl(regs + EXYNOS5_DRD_PHYCLKRST);
phyclkrst &= ~(PHYCLKRST_REF_SSP_EN |
PHYCLKRST_SSC_EN |
PHYCLKRST_COMMONONN);
writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
/* Control PHYTEST to remove leakage current */
phytest = readl(regs + EXYNOS5_DRD_PHYTEST);
phytest |= (PHYTEST_POWERDOWN_SSP |
PHYTEST_POWERDOWN_HSP);
writel(phytest, regs + EXYNOS5_DRD_PHYTEST);
}
static int samsung_usb3phy_init(struct usb_phy *phy)
{
struct samsung_usbphy *sphy;
unsigned long flags;
int ret = 0;
sphy = phy_to_sphy(phy);
/* Enable the phy clock */
ret = clk_prepare_enable(sphy->clk);
if (ret) {
dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
return ret;
}
spin_lock_irqsave(&sphy->lock, flags);
/* setting default phy-type for USB 3.0 */
samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
/* Disable phy isolation */
if (sphy->drv_data->set_isolation)
sphy->drv_data->set_isolation(sphy, false);
/* Initialize usb phy registers */
sphy->drv_data->phy_enable(sphy);
spin_unlock_irqrestore(&sphy->lock, flags);
/* Disable the phy clock */
clk_disable_unprepare(sphy->clk);
return ret;
}
/*
* The function passed to the usb driver for phy shutdown
*/
static void samsung_usb3phy_shutdown(struct usb_phy *phy)
{
struct samsung_usbphy *sphy;
unsigned long flags;
sphy = phy_to_sphy(phy);
if (clk_prepare_enable(sphy->clk)) {
dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
return;
}
spin_lock_irqsave(&sphy->lock, flags);
/* setting default phy-type for USB 3.0 */
samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
/* De-initialize usb phy registers */
sphy->drv_data->phy_disable(sphy);
/* Enable phy isolation */
if (sphy->drv_data->set_isolation)
sphy->drv_data->set_isolation(sphy, true);
spin_unlock_irqrestore(&sphy->lock, flags);
clk_disable_unprepare(sphy->clk);
}
static int samsung_usb3phy_probe(struct platform_device *pdev)
{
struct samsung_usbphy *sphy;
struct samsung_usbphy_data *pdata = dev_get_platdata(&pdev->dev);
struct device *dev = &pdev->dev;
struct resource *phy_mem;
void __iomem *phy_base;
struct clk *clk;
int ret;
phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
phy_base = devm_ioremap_resource(dev, phy_mem);
if (IS_ERR(phy_base))
return PTR_ERR(phy_base);
sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
if (!sphy)
return -ENOMEM;
clk = devm_clk_get(dev, "usbdrd30");
if (IS_ERR(clk)) {
dev_err(dev, "Failed to get device clock\n");
return PTR_ERR(clk);
}
sphy->dev = dev;
if (dev->of_node) {
ret = samsung_usbphy_parse_dt(sphy);
if (ret < 0)
return ret;
} else {
if (!pdata) {
dev_err(dev, "no platform data specified\n");
return -EINVAL;
}
}
sphy->plat = pdata;
sphy->regs = phy_base;
sphy->clk = clk;
sphy->phy.dev = sphy->dev;
sphy->phy.label = "samsung-usb3phy";
sphy->phy.type = USB_PHY_TYPE_USB3;
sphy->phy.init = samsung_usb3phy_init;
sphy->phy.shutdown = samsung_usb3phy_shutdown;
sphy->drv_data = samsung_usbphy_get_driver_data(pdev);
sphy->ref_clk_freq = samsung_usbphy_get_refclk_freq(sphy);
if (sphy->ref_clk_freq < 0)
return -EINVAL;
spin_lock_init(&sphy->lock);
platform_set_drvdata(pdev, sphy);
return usb_add_phy_dev(&sphy->phy);
}
static int samsung_usb3phy_remove(struct platform_device *pdev)
{
struct samsung_usbphy *sphy = platform_get_drvdata(pdev);
usb_remove_phy(&sphy->phy);
if (sphy->pmuregs)
iounmap(sphy->pmuregs);
if (sphy->sysreg)
iounmap(sphy->sysreg);
return 0;
}
static struct samsung_usbphy_drvdata usb3phy_exynos5 = {
.cpu_type = TYPE_EXYNOS5250,
.devphy_en_mask = EXYNOS_USBPHY_ENABLE,
.rate_to_clksel = samsung_usbphy_rate_to_clksel_4x12,
.set_isolation = samsung_usbphy_set_isolation_4210,
.phy_enable = samsung_exynos5_usb3phy_enable,
.phy_disable = samsung_exynos5_usb3phy_disable,
};
#ifdef CONFIG_OF
static const struct of_device_id samsung_usbphy_dt_match[] = {
{
.compatible = "samsung,exynos5250-usb3phy",
.data = &usb3phy_exynos5
},
{},
};
MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
#endif
static struct platform_device_id samsung_usbphy_driver_ids[] = {
{
.name = "exynos5250-usb3phy",
.driver_data = (unsigned long)&usb3phy_exynos5,
},
{},
};
MODULE_DEVICE_TABLE(platform, samsung_usbphy_driver_ids);
static struct platform_driver samsung_usb3phy_driver = {
.probe = samsung_usb3phy_probe,
.remove = samsung_usb3phy_remove,
.id_table = samsung_usbphy_driver_ids,
.driver = {
.name = "samsung-usb3phy",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(samsung_usbphy_dt_match),
},
};
module_platform_driver(samsung_usb3phy_driver);
MODULE_DESCRIPTION("Samsung USB 3.0 phy controller");
MODULE_AUTHOR("Vivek Gautam <gautam.vivek@samsung.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:samsung-usb3phy");