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

164 lines
4.1 KiB
C

/*
* Rockchip usb PHY driver
*
* Copyright (C) 2014 Yunzhi Li <lyz@rock-chips.com>
* Copyright (C) 2014 ROCKCHIP, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*
* 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/clk.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
/*
* The higher 16-bit of this register is used for write protection
* only if BIT(13 + 16) set to 1 the BIT(13) can be written.
*/
#define SIDDQ_WRITE_ENA BIT(29)
#define SIDDQ_ON BIT(13)
#define SIDDQ_OFF (0 << 13)
struct rockchip_usb_phy {
unsigned int reg_offset;
struct regmap *reg_base;
struct clk *clk;
struct phy *phy;
};
static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
bool siddq)
{
return regmap_write(phy->reg_base, phy->reg_offset,
SIDDQ_WRITE_ENA | (siddq ? SIDDQ_ON : SIDDQ_OFF));
}
static int rockchip_usb_phy_power_off(struct phy *_phy)
{
struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
int ret = 0;
/* Power down usb phy analog blocks by set siddq 1 */
ret = rockchip_usb_phy_power(phy, 1);
if (ret)
return ret;
clk_disable_unprepare(phy->clk);
return 0;
}
static int rockchip_usb_phy_power_on(struct phy *_phy)
{
struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
int ret = 0;
ret = clk_prepare_enable(phy->clk);
if (ret)
return ret;
/* Power up usb phy analog blocks by set siddq 0 */
ret = rockchip_usb_phy_power(phy, 0);
if (ret) {
clk_disable_unprepare(phy->clk);
return ret;
}
return 0;
}
static const struct phy_ops ops = {
.power_on = rockchip_usb_phy_power_on,
.power_off = rockchip_usb_phy_power_off,
.owner = THIS_MODULE,
};
static int rockchip_usb_phy_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct rockchip_usb_phy *rk_phy;
struct phy_provider *phy_provider;
struct device_node *child;
struct regmap *grf;
unsigned int reg_offset;
int err;
grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
if (IS_ERR(grf)) {
dev_err(&pdev->dev, "Missing rockchip,grf property\n");
return PTR_ERR(grf);
}
for_each_available_child_of_node(dev->of_node, child) {
rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);
if (!rk_phy)
return -ENOMEM;
if (of_property_read_u32(child, "reg", &reg_offset)) {
dev_err(dev, "missing reg property in node %s\n",
child->name);
return -EINVAL;
}
rk_phy->reg_offset = reg_offset;
rk_phy->reg_base = grf;
rk_phy->clk = of_clk_get_by_name(child, "phyclk");
if (IS_ERR(rk_phy->clk))
rk_phy->clk = NULL;
rk_phy->phy = devm_phy_create(dev, child, &ops);
if (IS_ERR(rk_phy->phy)) {
dev_err(dev, "failed to create PHY\n");
return PTR_ERR(rk_phy->phy);
}
phy_set_drvdata(rk_phy->phy, rk_phy);
/* only power up usb phy when it use, so disable it when init*/
err = rockchip_usb_phy_power(rk_phy, 1);
if (err)
return err;
}
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 rockchip_usb_phy_dt_ids[] = {
{ .compatible = "rockchip,rk3288-usb-phy" },
{}
};
MODULE_DEVICE_TABLE(of, rockchip_usb_phy_dt_ids);
static struct platform_driver rockchip_usb_driver = {
.probe = rockchip_usb_phy_probe,
.driver = {
.name = "rockchip-usb-phy",
.of_match_table = rockchip_usb_phy_dt_ids,
},
};
module_platform_driver(rockchip_usb_driver);
MODULE_AUTHOR("Yunzhi Li <lyz@rock-chips.com>");
MODULE_DESCRIPTION("Rockchip USB 2.0 PHY driver");
MODULE_LICENSE("GPL v2");