linux/drivers/usb/phy/phy-samsung-usb.c

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/* linux/drivers/usb/phy/phy-samsung-usb.c
*
* Copyright (c) 2012 Samsung Electronics Co., Ltd.
* http://www.samsung.com
*
* Author: Praveen Paneri <p.paneri@samsung.com>
*
* Samsung USB-PHY helper driver with common function calls;
* interacts with Samsung USB 2.0 PHY controller driver and later
* with Samsung USB 3.0 PHY driver.
*
* 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/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/usb/samsung_usb_phy.h>
#include "phy-samsung-usb.h"
int samsung_usbphy_parse_dt(struct samsung_usbphy *sphy)
{
struct device_node *usbphy_sys;
/* Getting node for system controller interface for usb-phy */
usbphy_sys = of_get_child_by_name(sphy->dev->of_node, "usbphy-sys");
if (!usbphy_sys) {
dev_err(sphy->dev, "No sys-controller interface for usb-phy\n");
return -ENODEV;
}
sphy->pmuregs = of_iomap(usbphy_sys, 0);
if (sphy->pmuregs == NULL) {
dev_err(sphy->dev, "Can't get usb-phy pmu control register\n");
goto err0;
}
sphy->sysreg = of_iomap(usbphy_sys, 1);
/*
* Not returning error code here, since this situation is not fatal.
* Few SoCs may not have this switch available
*/
if (sphy->sysreg == NULL)
dev_warn(sphy->dev, "Can't get usb-phy sysreg cfg register\n");
of_node_put(usbphy_sys);
return 0;
err0:
of_node_put(usbphy_sys);
return -ENXIO;
}
EXPORT_SYMBOL_GPL(samsung_usbphy_parse_dt);
/*
* Set isolation here for phy.
* Here 'on = true' would mean USB PHY block is isolated, hence
* de-activated and vice-versa.
*/
void samsung_usbphy_set_isolation(struct samsung_usbphy *sphy, bool on)
{
void __iomem *reg = NULL;
u32 reg_val;
u32 en_mask = 0;
if (!sphy->pmuregs) {
dev_warn(sphy->dev, "Can't set pmu isolation\n");
return;
}
switch (sphy->drv_data->cpu_type) {
case TYPE_S3C64XX:
/*
* Do nothing: We will add here once S3C64xx goes for DT support
*/
break;
case TYPE_EXYNOS4210:
/*
* Fall through since exynos4210 and exynos5250 have similar
* register architecture: two separate registers for host and
* device phy control with enable bit at position 0.
*/
case TYPE_EXYNOS5250:
if (sphy->phy_type == USB_PHY_TYPE_DEVICE) {
reg = sphy->pmuregs +
sphy->drv_data->devphy_reg_offset;
en_mask = sphy->drv_data->devphy_en_mask;
} else if (sphy->phy_type == USB_PHY_TYPE_HOST) {
reg = sphy->pmuregs +
sphy->drv_data->hostphy_reg_offset;
en_mask = sphy->drv_data->hostphy_en_mask;
}
break;
default:
dev_err(sphy->dev, "Invalid SoC type\n");
return;
}
reg_val = readl(reg);
if (on)
reg_val &= ~en_mask;
else
reg_val |= en_mask;
writel(reg_val, reg);
}
EXPORT_SYMBOL_GPL(samsung_usbphy_set_isolation);
/*
* Configure the mode of working of usb-phy here: HOST/DEVICE.
*/
void samsung_usbphy_cfg_sel(struct samsung_usbphy *sphy)
{
u32 reg;
if (!sphy->sysreg) {
dev_warn(sphy->dev, "Can't configure specified phy mode\n");
return;
}
reg = readl(sphy->sysreg);
if (sphy->phy_type == USB_PHY_TYPE_DEVICE)
reg &= ~EXYNOS_USB20PHY_CFG_HOST_LINK;
else if (sphy->phy_type == USB_PHY_TYPE_HOST)
reg |= EXYNOS_USB20PHY_CFG_HOST_LINK;
writel(reg, sphy->sysreg);
}
EXPORT_SYMBOL_GPL(samsung_usbphy_cfg_sel);
/*
* PHYs are different for USB Device and USB Host.
* This make sure that correct PHY type is selected before
* any operation on PHY.
*/
int samsung_usbphy_set_type(struct usb_phy *phy,
enum samsung_usb_phy_type phy_type)
{
struct samsung_usbphy *sphy = phy_to_sphy(phy);
sphy->phy_type = phy_type;
return 0;
}
EXPORT_SYMBOL_GPL(samsung_usbphy_set_type);
/*
* Returns reference clock frequency selection value
*/
int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
{
struct clk *ref_clk;
int refclk_freq = 0;
/*
* In exynos5250 USB host and device PHY use
* external crystal clock XXTI
*/
if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250)
ref_clk = devm_clk_get(sphy->dev, "ext_xtal");
else
ref_clk = devm_clk_get(sphy->dev, "xusbxti");
if (IS_ERR(ref_clk)) {
dev_err(sphy->dev, "Failed to get reference clock\n");
return PTR_ERR(ref_clk);
}
if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250) {
/* set clock frequency for PLL */
switch (clk_get_rate(ref_clk)) {
case 9600 * KHZ:
refclk_freq = FSEL_CLKSEL_9600K;
break;
case 10 * MHZ:
refclk_freq = FSEL_CLKSEL_10M;
break;
case 12 * MHZ:
refclk_freq = FSEL_CLKSEL_12M;
break;
case 19200 * KHZ:
refclk_freq = FSEL_CLKSEL_19200K;
break;
case 20 * MHZ:
refclk_freq = FSEL_CLKSEL_20M;
break;
case 50 * MHZ:
refclk_freq = FSEL_CLKSEL_50M;
break;
case 24 * MHZ:
default:
/* default reference clock */
refclk_freq = FSEL_CLKSEL_24M;
break;
}
} else {
switch (clk_get_rate(ref_clk)) {
case 12 * MHZ:
refclk_freq = PHYCLK_CLKSEL_12M;
break;
case 24 * MHZ:
refclk_freq = PHYCLK_CLKSEL_24M;
break;
case 48 * MHZ:
refclk_freq = PHYCLK_CLKSEL_48M;
break;
default:
if (sphy->drv_data->cpu_type == TYPE_S3C64XX)
refclk_freq = PHYCLK_CLKSEL_48M;
else
refclk_freq = PHYCLK_CLKSEL_24M;
break;
}
}
clk_put(ref_clk);
return refclk_freq;
}
EXPORT_SYMBOL_GPL(samsung_usbphy_get_refclk_freq);