// SPDX-License-Identifier: GPL-2.0
/*
* USB Glue for Amlogic G12A SoCs
*
* Copyright (c) 2019 BayLibre, SAS
* Author: Neil Armstrong <narmstrong@baylibre.com>
*/
/*
* The USB is organized with a glue around the DWC3 Controller IP as :
* - Control registers for each USB2 Ports
* - Control registers for the USB PHY layer
* - SuperSpeed PHY can be enabled only if port is used
* - Dynamic OTG switching with ID change interrupt
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/reset.h>
#include <linux/phy/phy.h>
#include <linux/usb/otg.h>
#include <linux/usb/role.h>
#include <linux/regulator/consumer.h>
/* USB2 Ports Control Registers */
#define U2P_REG_SIZE 0x20
#define U2P_R0 0x0
#define U2P_R0_HOST_DEVICE BIT(0)
#define U2P_R0_POWER_OK BIT(1)
#define U2P_R0_HAST_MODE BIT(2)
#define U2P_R0_POWER_ON_RESET BIT(3)
#define U2P_R0_ID_PULLUP BIT(4)
#define U2P_R0_DRV_VBUS BIT(5)
#define U2P_R1 0x4
#define U2P_R1_PHY_READY BIT(0)
#define U2P_R1_ID_DIG BIT(1)
#define U2P_R1_OTG_SESSION_VALID BIT(2)
#define U2P_R1_VBUS_VALID BIT(3)
/* USB Glue Control Registers */
#define USB_R0 0x80
#define USB_R0_P30_LANE0_TX2RX_LOOPBACK BIT(17)
#define USB_R0_P30_LANE0_EXT_PCLK_REQ BIT(18)
#define USB_R0_P30_PCS_RX_LOS_MASK_VAL_MASK GENMASK(28, 19)
#define USB_R0_U2D_SS_SCALEDOWN_MODE_MASK GENMASK(30, 29)
#define USB_R0_U2D_ACT BIT(31)
#define USB_R1 0x84
#define USB_R1_U3H_BIGENDIAN_GS BIT(0)
#define USB_R1_U3H_PME_ENABLE BIT(1)
#define USB_R1_U3H_HUB_PORT_OVERCURRENT_MASK GENMASK(4, 2)
#define USB_R1_U3H_HUB_PORT_PERM_ATTACH_MASK GENMASK(9, 7)
#define USB_R1_U3H_HOST_U2_PORT_DISABLE_MASK GENMASK(13, 12)
#define USB_R1_U3H_HOST_U3_PORT_DISABLE BIT(16)
#define USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT BIT(17)
#define USB_R1_U3H_HOST_MSI_ENABLE BIT(18)
#define USB_R1_U3H_FLADJ_30MHZ_REG_MASK GENMASK(24, 19)
#define USB_R1_P30_PCS_TX_SWING_FULL_MASK GENMASK(31, 25)
#define USB_R2 0x88
#define USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK GENMASK(25, 20)
#define USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK GENMASK(31, 26)
#define USB_R3 0x8c
#define USB_R3_P30_SSC_ENABLE BIT(0)
#define USB_R3_P30_SSC_RANGE_MASK GENMASK(3, 1)
#define USB_R3_P30_SSC_REF_CLK_SEL_MASK GENMASK(12, 4)
#define USB_R3_P30_REF_SSP_EN BIT(13)
#define USB_R4 0x90
#define USB_R4_P21_PORT_RESET_0 BIT(0)
#define USB_R4_P21_SLEEP_M0 BIT(1)
#define USB_R4_MEM_PD_MASK GENMASK(3, 2)
#define USB_R4_P21_ONLY BIT(4)
#define USB_R5 0x94
#define USB_R5_ID_DIG_SYNC BIT(0)
#define USB_R5_ID_DIG_REG BIT(1)
#define USB_R5_ID_DIG_CFG_MASK GENMASK(3, 2)
#define USB_R5_ID_DIG_EN_0 BIT(4)
#define USB_R5_ID_DIG_EN_1 BIT(5)
#define USB_R5_ID_DIG_CURR BIT(6)
#define USB_R5_ID_DIG_IRQ BIT(7)
#define USB_R5_ID_DIG_TH_MASK GENMASK(15, 8)
#define USB_R5_ID_DIG_CNT_MASK GENMASK(23, 16)
enum {
USB2_HOST_PHY = 0,
USB2_OTG_PHY,
USB3_HOST_PHY,
PHY_COUNT,
};
static const char *phy_names[PHY_COUNT] = {
"usb2-phy0", "usb2-phy1", "usb3-phy0",
};
struct dwc3_meson_g12a {
struct device *dev;
struct regmap *regmap;
struct clk *clk;
struct reset_control *reset;
struct phy *phys[PHY_COUNT];
enum usb_dr_mode otg_mode;
enum phy_mode otg_phy_mode;
unsigned int usb2_ports;
unsigned int usb3_ports;
struct regulator *vbus;
struct usb_role_switch_desc switch_desc;
struct usb_role_switch *role_switch;
};
static void dwc3_meson_g12a_usb2_set_mode(struct dwc3_meson_g12a *priv,
int i, enum phy_mode mode)
{
if (mode == PHY_MODE_USB_HOST)
regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
U2P_R0_HOST_DEVICE,
U2P_R0_HOST_DEVICE);
else
regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
U2P_R0_HOST_DEVICE, 0);
}
static int dwc3_meson_g12a_usb2_init(struct dwc3_meson_g12a *priv)
{
int i;
if (priv->otg_mode == USB_DR_MODE_PERIPHERAL)
priv->otg_phy_mode = PHY_MODE_USB_DEVICE;
else
priv->otg_phy_mode = PHY_MODE_USB_HOST;
for (i = 0 ; i < USB3_HOST_PHY ; ++i) {
if (!priv->phys[i])
continue;
regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
U2P_R0_POWER_ON_RESET,
U2P_R0_POWER_ON_RESET);
if (i == USB2_OTG_PHY) {
regmap_update_bits(priv->regmap,
U2P_R0 + (U2P_REG_SIZE * i),
U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS,
U2P_R0_ID_PULLUP | U2P_R0_DRV_VBUS);
dwc3_meson_g12a_usb2_set_mode(priv, i,
priv->otg_phy_mode);
} else
dwc3_meson_g12a_usb2_set_mode(priv, i,
PHY_MODE_USB_HOST);
regmap_update_bits(priv->regmap, U2P_R0 + (U2P_REG_SIZE * i),
U2P_R0_POWER_ON_RESET, 0);
}
return 0;
}
static void dwc3_meson_g12a_usb3_init(struct dwc3_meson_g12a *priv)
{
regmap_update_bits(priv->regmap, USB_R3,
USB_R3_P30_SSC_RANGE_MASK |
USB_R3_P30_REF_SSP_EN,
USB_R3_P30_SSC_ENABLE |
FIELD_PREP(USB_R3_P30_SSC_RANGE_MASK, 2) |
USB_R3_P30_REF_SSP_EN);
udelay(2);
regmap_update_bits(priv->regmap, USB_R2,
USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK,
FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_3P5DB_MASK, 0x15));
regmap_update_bits(priv->regmap, USB_R2,
USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK,
FIELD_PREP(USB_R2_P30_PCS_TX_DEEMPH_6DB_MASK, 0x20));
udelay(2);
regmap_update_bits(priv->regmap, USB_R1,
USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT,
USB_R1_U3H_HOST_PORT_POWER_CONTROL_PRESENT);
regmap_update_bits(priv->regmap, USB_R1,
USB_R1_P30_PCS_TX_SWING_FULL_MASK,
FIELD_PREP(USB_R1_P30_PCS_TX_SWING_FULL_MASK, 127));
}
static void dwc3_meson_g12a_usb_otg_apply_mode(struct dwc3_meson_g12a *priv)
{
if (priv->otg_phy_mode == PHY_MODE_USB_DEVICE) {
regmap_update_bits(priv->regmap, USB_R0,
USB_R0_U2D_ACT, USB_R0_U2D_ACT);
regmap_update_bits(priv->regmap, USB_R0,
USB_R0_U2D_SS_SCALEDOWN_MODE_MASK, 0);
regmap_update_bits(priv->regmap, USB_R4,
USB_R4_P21_SLEEP_M0, USB_R4_P21_SLEEP_M0);
} else {
regmap_update_bits(priv->regmap, USB_R0,
USB_R0_U2D_ACT, 0);
regmap_update_bits(priv->regmap, USB_R4,
USB_R4_P21_SLEEP_M0, 0);
}
}
static int dwc3_meson_g12a_usb_init(struct dwc3_meson_g12a *priv)
{
int ret;
ret = dwc3_meson_g12a_usb2_init(priv);
if (ret)
return ret;
regmap_update_bits(priv->regmap, USB_R1,
USB_R1_U3H_FLADJ_30MHZ_REG_MASK,
FIELD_PREP(USB_R1_U3H_FLADJ_30MHZ_REG_MASK, 0x20));
regmap_update_bits(priv->regmap, USB_R5,
USB_R5_ID_DIG_EN_0,
USB_R5_ID_DIG_EN_0);
regmap_update_bits(priv->regmap, USB_R5,
USB_R5_ID_DIG_EN_1,
USB_R5_ID_DIG_EN_1);
regmap_update_bits(priv->regmap, USB_R5,
USB_R5_ID_DIG_TH_MASK,
FIELD_PREP(USB_R5_ID_DIG_TH_MASK, 0xff));
/* If we have an actual SuperSpeed port, initialize it */
if (priv->usb3_ports)
dwc3_meson_g12a_usb3_init(priv);
dwc3_meson_g12a_usb_otg_apply_mode(priv);
return 0;
}
static const struct regmap_config phy_meson_g12a_usb3_regmap_conf = {
.reg_bits = 8,
.val_bits = 32,
.reg_stride = 4,
.max_register = USB_R5,
};
static int dwc3_meson_g12a_get_phys(struct dwc3_meson_g12a *priv)
{
int i;
for (i = 0 ; i < PHY_COUNT ; ++i) {
priv->phys[i] = devm_phy_optional_get(priv->dev, phy_names[i]);
if (!priv->phys[i])
continue;
if (IS_ERR(priv->phys[i]))
return PTR_ERR(priv->phys[i]);
if (i == USB3_HOST_PHY)
priv->usb3_ports++;
else
priv->usb2_ports++;
}
dev_info(priv->dev, "USB2 ports: %d\n", priv->usb2_ports);
dev_info(priv->dev, "USB3 ports: %d\n", priv->usb3_ports);
return 0;
}
static enum phy_mode dwc3_meson_g12a_get_id(struct dwc3_meson_g12a *priv)
{
u32 reg;
regmap_read(priv->regmap, USB_R5, ®);
if (reg & (USB_R5_ID_DIG_SYNC | USB_R5_ID_DIG_REG))
return PHY_MODE_USB_DEVICE;
return PHY_MODE_USB_HOST;
}
static int dwc3_meson_g12a_otg_mode_set(struct dwc3_meson_g12a *priv,
enum phy_mode mode)
{
int ret;
if (!priv->phys[USB2_OTG_PHY])
return -EINVAL;
if (mode == PHY_MODE_USB_HOST)
dev_info(priv->dev, "switching to Host Mode\n");
else
dev_info(priv->dev, "switching to Device Mode\n");
if (priv->vbus) {
if (mode == PHY_MODE_USB_DEVICE)
ret = regulator_disable(priv->vbus);
else
ret = regulator_enable(priv->vbus);
if (ret)
return ret;
}
priv->otg_phy_mode = mode;
dwc3_meson_g12a_usb2_set_mode(priv, USB2_OTG_PHY, mode);
dwc3_meson_g12a_usb_otg_apply_mode(priv);
return 0;
}
static int dwc3_meson_g12a_role_set(struct device *dev, enum usb_role role)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
enum phy_mode mode;
if (role == USB_ROLE_NONE)
return 0;
mode = (role == USB_ROLE_HOST) ? PHY_MODE_USB_HOST
: PHY_MODE_USB_DEVICE;
if (mode == priv->otg_phy_mode)
return 0;
return dwc3_meson_g12a_otg_mode_set(priv, mode);
}
static enum usb_role dwc3_meson_g12a_role_get(struct device *dev)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
return priv->otg_phy_mode == PHY_MODE_USB_HOST ?
USB_ROLE_HOST : USB_ROLE_DEVICE;
}
static irqreturn_t dwc3_meson_g12a_irq_thread(int irq, void *data)
{
struct dwc3_meson_g12a *priv = data;
enum phy_mode otg_id;
otg_id = dwc3_meson_g12a_get_id(priv);
if (otg_id != priv->otg_phy_mode) {
if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
dev_warn(priv->dev, "Failed to switch OTG mode\n");
}
regmap_update_bits(priv->regmap, USB_R5, USB_R5_ID_DIG_IRQ, 0);
return IRQ_HANDLED;
}
static struct device *dwc3_meson_g12_find_child(struct device *dev,
const char *compatible)
{
struct platform_device *pdev;
struct device_node *np;
np = of_get_compatible_child(dev->of_node, compatible);
if (!np)
return NULL;
pdev = of_find_device_by_node(np);
of_node_put(np);
if (!pdev)
return NULL;
return &pdev->dev;
}
static int dwc3_meson_g12a_probe(struct platform_device *pdev)
{
struct dwc3_meson_g12a *priv;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
void __iomem *base;
enum phy_mode otg_id;
int ret, i, irq;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return PTR_ERR(base);
priv->regmap = devm_regmap_init_mmio(dev, base,
&phy_meson_g12a_usb3_regmap_conf);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
priv->vbus = devm_regulator_get_optional(dev, "vbus");
if (IS_ERR(priv->vbus)) {
if (PTR_ERR(priv->vbus) == -EPROBE_DEFER)
return PTR_ERR(priv->vbus);
priv->vbus = NULL;
}
priv->clk = devm_clk_get(dev, NULL);
if (IS_ERR(priv->clk))
return PTR_ERR(priv->clk);
ret = clk_prepare_enable(priv->clk);
if (ret)
return ret;
devm_add_action_or_reset(dev,
(void(*)(void *))clk_disable_unprepare,
priv->clk);
platform_set_drvdata(pdev, priv);
priv->dev = dev;
priv->reset = devm_reset_control_get(dev, NULL);
if (IS_ERR(priv->reset)) {
ret = PTR_ERR(priv->reset);
dev_err(dev, "failed to get device reset, err=%d\n", ret);
return ret;
}
ret = reset_control_reset(priv->reset);
if (ret)
return ret;
ret = dwc3_meson_g12a_get_phys(priv);
if (ret)
return ret;
if (priv->vbus) {
ret = regulator_enable(priv->vbus);
if (ret)
return ret;
}
/* Get dr_mode */
priv->otg_mode = usb_get_dr_mode(dev);
if (priv->otg_mode == USB_DR_MODE_OTG) {
/* Ack irq before registering */
regmap_update_bits(priv->regmap, USB_R5,
USB_R5_ID_DIG_IRQ, 0);
irq = platform_get_irq(pdev, 0);
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
dwc3_meson_g12a_irq_thread,
IRQF_ONESHOT, pdev->name, priv);
if (ret)
return ret;
}
dwc3_meson_g12a_usb_init(priv);
/* Init PHYs */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_init(priv->phys[i]);
if (ret)
return ret;
}
/* Set PHY Power */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_power_on(priv->phys[i]);
if (ret)
goto err_phys_exit;
}
ret = of_platform_populate(np, NULL, NULL, dev);
if (ret) {
clk_disable_unprepare(priv->clk);
goto err_phys_power;
}
/* Setup OTG mode corresponding to the ID pin */
if (priv->otg_mode == USB_DR_MODE_OTG) {
otg_id = dwc3_meson_g12a_get_id(priv);
if (otg_id != priv->otg_phy_mode) {
if (dwc3_meson_g12a_otg_mode_set(priv, otg_id))
dev_warn(dev, "Failed to switch OTG mode\n");
}
}
/* Setup role switcher */
priv->switch_desc.usb2_port = dwc3_meson_g12_find_child(dev,
"snps,dwc3");
priv->switch_desc.udc = dwc3_meson_g12_find_child(dev, "snps,dwc2");
priv->switch_desc.allow_userspace_control = true;
priv->switch_desc.set = dwc3_meson_g12a_role_set;
priv->switch_desc.get = dwc3_meson_g12a_role_get;
priv->role_switch = usb_role_switch_register(dev, &priv->switch_desc);
if (IS_ERR(priv->role_switch))
dev_warn(dev, "Unable to register Role Switch\n");
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
pm_runtime_get_sync(dev);
return 0;
err_phys_power:
for (i = 0 ; i < PHY_COUNT ; ++i)
phy_power_off(priv->phys[i]);
err_phys_exit:
for (i = 0 ; i < PHY_COUNT ; ++i)
phy_exit(priv->phys[i]);
return ret;
}
static int dwc3_meson_g12a_remove(struct platform_device *pdev)
{
struct dwc3_meson_g12a *priv = platform_get_drvdata(pdev);
struct device *dev = &pdev->dev;
int i;
usb_role_switch_unregister(priv->role_switch);
of_platform_depopulate(dev);
for (i = 0 ; i < PHY_COUNT ; ++i) {
phy_power_off(priv->phys[i]);
phy_exit(priv->phys[i]);
}
pm_runtime_disable(dev);
pm_runtime_put_noidle(dev);
pm_runtime_set_suspended(dev);
return 0;
}
static int __maybe_unused dwc3_meson_g12a_runtime_suspend(struct device *dev)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
clk_disable(priv->clk);
return 0;
}
static int __maybe_unused dwc3_meson_g12a_runtime_resume(struct device *dev)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
return clk_enable(priv->clk);
}
static int __maybe_unused dwc3_meson_g12a_suspend(struct device *dev)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
int i, ret;
if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
ret = regulator_disable(priv->vbus);
if (ret)
return ret;
}
for (i = 0 ; i < PHY_COUNT ; ++i) {
phy_power_off(priv->phys[i]);
phy_exit(priv->phys[i]);
}
reset_control_assert(priv->reset);
return 0;
}
static int __maybe_unused dwc3_meson_g12a_resume(struct device *dev)
{
struct dwc3_meson_g12a *priv = dev_get_drvdata(dev);
int i, ret;
reset_control_deassert(priv->reset);
dwc3_meson_g12a_usb_init(priv);
/* Init PHYs */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_init(priv->phys[i]);
if (ret)
return ret;
}
/* Set PHY Power */
for (i = 0 ; i < PHY_COUNT ; ++i) {
ret = phy_power_on(priv->phys[i]);
if (ret)
return ret;
}
if (priv->vbus && priv->otg_phy_mode == PHY_MODE_USB_HOST) {
ret = regulator_enable(priv->vbus);
if (ret)
return ret;
}
return 0;
}
static const struct dev_pm_ops dwc3_meson_g12a_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(dwc3_meson_g12a_suspend, dwc3_meson_g12a_resume)
SET_RUNTIME_PM_OPS(dwc3_meson_g12a_runtime_suspend,
dwc3_meson_g12a_runtime_resume, NULL)
};
static const struct of_device_id dwc3_meson_g12a_match[] = {
{ .compatible = "amlogic,meson-g12a-usb-ctrl" },
{ /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, dwc3_meson_g12a_match);
static struct platform_driver dwc3_meson_g12a_driver = {
.probe = dwc3_meson_g12a_probe,
.remove = dwc3_meson_g12a_remove,
.driver = {
.name = "dwc3-meson-g12a",
.of_match_table = dwc3_meson_g12a_match,
.pm = &dwc3_meson_g12a_dev_pm_ops,
},
};
module_platform_driver(dwc3_meson_g12a_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Amlogic Meson G12A USB Glue Layer");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");