linux/drivers/phy/phy-sun4i-usb.c
Hans de Goede 24fe86a617 phy: sun4i-usb: Add a sunxi specific function for setting squelch-detect
The sunxi otg phy has a bug where it wrongly detects a high speed squelch
when reset on the root port gets de-asserted with a lo-speed device.

The workaround for this is to disable squelch detect before de-asserting
reset, and re-enabling it after the reset de-assert is done. Add a sunxi
specific phy function to allow the sunxi-musb glue to do this.

Acked-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2015-05-27 12:20:36 -05:00

348 lines
8.6 KiB
C

/*
* Allwinner sun4i USB phy driver
*
* Copyright (C) 2014 Hans de Goede <hdegoede@redhat.com>
*
* Based on code from
* Allwinner Technology Co., Ltd. <www.allwinnertech.com>
*
* Modelled after: Samsung S5P/EXYNOS SoC series MIPI CSIS/DSIM DPHY driver
* Copyright (C) 2013 Samsung Electronics Co., Ltd.
* Author: Sylwester Nawrocki <s.nawrocki@samsung.com>
*
* 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, or
* (at your option) any later version.
*
* 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/err.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/phy/phy-sun4i-usb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#define REG_ISCR 0x00
#define REG_PHYCTL 0x04
#define REG_PHYBIST 0x08
#define REG_PHYTUNE 0x0c
#define PHYCTL_DATA BIT(7)
#define SUNXI_AHB_ICHR8_EN BIT(10)
#define SUNXI_AHB_INCR4_BURST_EN BIT(9)
#define SUNXI_AHB_INCRX_ALIGN_EN BIT(8)
#define SUNXI_ULPI_BYPASS_EN BIT(0)
/* Common Control Bits for Both PHYs */
#define PHY_PLL_BW 0x03
#define PHY_RES45_CAL_EN 0x0c
/* Private Control Bits for Each PHY */
#define PHY_TX_AMPLITUDE_TUNE 0x20
#define PHY_TX_SLEWRATE_TUNE 0x22
#define PHY_VBUSVALID_TH_SEL 0x25
#define PHY_PULLUP_RES_SEL 0x27
#define PHY_OTG_FUNC_EN 0x28
#define PHY_VBUS_DET_EN 0x29
#define PHY_DISCON_TH_SEL 0x2a
#define PHY_SQUELCH_DETECT 0x3c
#define MAX_PHYS 3
struct sun4i_usb_phy_data {
void __iomem *base;
struct mutex mutex;
int num_phys;
u32 disc_thresh;
struct sun4i_usb_phy {
struct phy *phy;
void __iomem *pmu;
struct regulator *vbus;
struct reset_control *reset;
struct clk *clk;
int index;
} phys[MAX_PHYS];
};
#define to_sun4i_usb_phy_data(phy) \
container_of((phy), struct sun4i_usb_phy_data, phys[(phy)->index])
static void sun4i_usb_phy_write(struct sun4i_usb_phy *phy, u32 addr, u32 data,
int len)
{
struct sun4i_usb_phy_data *phy_data = to_sun4i_usb_phy_data(phy);
u32 temp, usbc_bit = BIT(phy->index * 2);
int i;
mutex_lock(&phy_data->mutex);
for (i = 0; i < len; i++) {
temp = readl(phy_data->base + REG_PHYCTL);
/* clear the address portion */
temp &= ~(0xff << 8);
/* set the address */
temp |= ((addr + i) << 8);
writel(temp, phy_data->base + REG_PHYCTL);
/* set the data bit and clear usbc bit*/
temp = readb(phy_data->base + REG_PHYCTL);
if (data & 0x1)
temp |= PHYCTL_DATA;
else
temp &= ~PHYCTL_DATA;
temp &= ~usbc_bit;
writeb(temp, phy_data->base + REG_PHYCTL);
/* pulse usbc_bit */
temp = readb(phy_data->base + REG_PHYCTL);
temp |= usbc_bit;
writeb(temp, phy_data->base + REG_PHYCTL);
temp = readb(phy_data->base + REG_PHYCTL);
temp &= ~usbc_bit;
writeb(temp, phy_data->base + REG_PHYCTL);
data >>= 1;
}
mutex_unlock(&phy_data->mutex);
}
static void sun4i_usb_phy_passby(struct sun4i_usb_phy *phy, int enable)
{
u32 bits, reg_value;
if (!phy->pmu)
return;
bits = SUNXI_AHB_ICHR8_EN | SUNXI_AHB_INCR4_BURST_EN |
SUNXI_AHB_INCRX_ALIGN_EN | SUNXI_ULPI_BYPASS_EN;
reg_value = readl(phy->pmu);
if (enable)
reg_value |= bits;
else
reg_value &= ~bits;
writel(reg_value, phy->pmu);
}
static int sun4i_usb_phy_init(struct phy *_phy)
{
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
struct sun4i_usb_phy_data *data = to_sun4i_usb_phy_data(phy);
int ret;
ret = clk_prepare_enable(phy->clk);
if (ret)
return ret;
ret = reset_control_deassert(phy->reset);
if (ret) {
clk_disable_unprepare(phy->clk);
return ret;
}
/* Enable USB 45 Ohm resistor calibration */
if (phy->index == 0)
sun4i_usb_phy_write(phy, PHY_RES45_CAL_EN, 0x01, 1);
/* Adjust PHY's magnitude and rate */
sun4i_usb_phy_write(phy, PHY_TX_AMPLITUDE_TUNE, 0x14, 5);
/* Disconnect threshold adjustment */
sun4i_usb_phy_write(phy, PHY_DISCON_TH_SEL, data->disc_thresh, 2);
sun4i_usb_phy_passby(phy, 1);
return 0;
}
static int sun4i_usb_phy_exit(struct phy *_phy)
{
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
sun4i_usb_phy_passby(phy, 0);
reset_control_assert(phy->reset);
clk_disable_unprepare(phy->clk);
return 0;
}
static int sun4i_usb_phy_power_on(struct phy *_phy)
{
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
int ret = 0;
if (phy->vbus)
ret = regulator_enable(phy->vbus);
return ret;
}
static int sun4i_usb_phy_power_off(struct phy *_phy)
{
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
if (phy->vbus)
regulator_disable(phy->vbus);
return 0;
}
void sun4i_usb_phy_set_squelch_detect(struct phy *_phy, bool enabled)
{
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
sun4i_usb_phy_write(phy, PHY_SQUELCH_DETECT, enabled ? 0 : 2, 2);
}
static struct phy_ops sun4i_usb_phy_ops = {
.init = sun4i_usb_phy_init,
.exit = sun4i_usb_phy_exit,
.power_on = sun4i_usb_phy_power_on,
.power_off = sun4i_usb_phy_power_off,
.owner = THIS_MODULE,
};
static struct phy *sun4i_usb_phy_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct sun4i_usb_phy_data *data = dev_get_drvdata(dev);
if (args->args[0] >= data->num_phys)
return ERR_PTR(-ENODEV);
return data->phys[args->args[0]].phy;
}
static int sun4i_usb_phy_probe(struct platform_device *pdev)
{
struct sun4i_usb_phy_data *data;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct phy_provider *phy_provider;
bool dedicated_clocks;
struct resource *res;
int i;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_init(&data->mutex);
if (of_device_is_compatible(np, "allwinner,sun5i-a13-usb-phy"))
data->num_phys = 2;
else
data->num_phys = 3;
if (of_device_is_compatible(np, "allwinner,sun4i-a10-usb-phy") ||
of_device_is_compatible(np, "allwinner,sun6i-a31-usb-phy"))
data->disc_thresh = 3;
else
data->disc_thresh = 2;
if (of_device_is_compatible(np, "allwinner,sun6i-a31-usb-phy"))
dedicated_clocks = true;
else
dedicated_clocks = false;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "phy_ctrl");
data->base = devm_ioremap_resource(dev, res);
if (IS_ERR(data->base))
return PTR_ERR(data->base);
for (i = 0; i < data->num_phys; i++) {
struct sun4i_usb_phy *phy = data->phys + i;
char name[16];
snprintf(name, sizeof(name), "usb%d_vbus", i);
phy->vbus = devm_regulator_get_optional(dev, name);
if (IS_ERR(phy->vbus)) {
if (PTR_ERR(phy->vbus) == -EPROBE_DEFER)
return -EPROBE_DEFER;
phy->vbus = NULL;
}
if (dedicated_clocks)
snprintf(name, sizeof(name), "usb%d_phy", i);
else
strlcpy(name, "usb_phy", sizeof(name));
phy->clk = devm_clk_get(dev, name);
if (IS_ERR(phy->clk)) {
dev_err(dev, "failed to get clock %s\n", name);
return PTR_ERR(phy->clk);
}
snprintf(name, sizeof(name), "usb%d_reset", i);
phy->reset = devm_reset_control_get(dev, name);
if (IS_ERR(phy->reset)) {
dev_err(dev, "failed to get reset %s\n", name);
return PTR_ERR(phy->reset);
}
if (i) { /* No pmu for usbc0 */
snprintf(name, sizeof(name), "pmu%d", i);
res = platform_get_resource_byname(pdev,
IORESOURCE_MEM, name);
phy->pmu = devm_ioremap_resource(dev, res);
if (IS_ERR(phy->pmu))
return PTR_ERR(phy->pmu);
}
phy->phy = devm_phy_create(dev, NULL, &sun4i_usb_phy_ops);
if (IS_ERR(phy->phy)) {
dev_err(dev, "failed to create PHY %d\n", i);
return PTR_ERR(phy->phy);
}
phy->index = i;
phy_set_drvdata(phy->phy, &data->phys[i]);
}
dev_set_drvdata(dev, data);
phy_provider = devm_of_phy_provider_register(dev, sun4i_usb_phy_xlate);
return PTR_ERR_OR_ZERO(phy_provider);
}
static const struct of_device_id sun4i_usb_phy_of_match[] = {
{ .compatible = "allwinner,sun4i-a10-usb-phy" },
{ .compatible = "allwinner,sun5i-a13-usb-phy" },
{ .compatible = "allwinner,sun6i-a31-usb-phy" },
{ .compatible = "allwinner,sun7i-a20-usb-phy" },
{ },
};
MODULE_DEVICE_TABLE(of, sun4i_usb_phy_of_match);
static struct platform_driver sun4i_usb_phy_driver = {
.probe = sun4i_usb_phy_probe,
.driver = {
.of_match_table = sun4i_usb_phy_of_match,
.name = "sun4i-usb-phy",
}
};
module_platform_driver(sun4i_usb_phy_driver);
MODULE_DESCRIPTION("Allwinner sun4i USB phy driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL v2");