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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2014 STMicroelectronics4 *5 * STMicroelectronics Generic PHY driver for STiH407 USB2.6 *7 * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>8 */9#include <linux/platform_device.h>10#include <linux/io.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/of.h>14#include <linux/of_platform.h>15#include <linux/clk.h>16#include <linux/regmap.h>17#include <linux/reset.h>18#include <linux/mfd/syscon.h>19#include <linux/phy/phy.h>20 21#define PHYPARAM_REG 122#define PHYCTRL_REG 223 24/* Default PHY_SEL and REFCLKSEL configuration */25#define STIH407_USB_PICOPHY_CTRL_PORT_CONF 0x626#define STIH407_USB_PICOPHY_CTRL_PORT_MASK 0x1f27 28/* ports parameters overriding */29#define STIH407_USB_PICOPHY_PARAM_DEF 0x39a4dc30#define STIH407_USB_PICOPHY_PARAM_MASK 0xffffffff31 32struct stih407_usb2_picophy {33 struct phy *phy;34 struct regmap *regmap;35 struct device *dev;36 struct reset_control *rstc;37 struct reset_control *rstport;38 int ctrl;39 int param;40};41 42static int stih407_usb2_pico_ctrl(struct stih407_usb2_picophy *phy_dev)43{44 reset_control_deassert(phy_dev->rstc);45 46 return regmap_update_bits(phy_dev->regmap, phy_dev->ctrl,47 STIH407_USB_PICOPHY_CTRL_PORT_MASK,48 STIH407_USB_PICOPHY_CTRL_PORT_CONF);49}50 51static int stih407_usb2_init_port(struct phy *phy)52{53 int ret;54 struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);55 56 stih407_usb2_pico_ctrl(phy_dev);57 58 ret = regmap_update_bits(phy_dev->regmap,59 phy_dev->param,60 STIH407_USB_PICOPHY_PARAM_MASK,61 STIH407_USB_PICOPHY_PARAM_DEF);62 if (ret)63 return ret;64 65 return reset_control_deassert(phy_dev->rstport);66}67 68static int stih407_usb2_exit_port(struct phy *phy)69{70 struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);71 72 /*73 * Only port reset is asserted, phy global reset is kept untouched74 * as other ports may still be active. When all ports are in reset75 * state, assumption is made that power will be cut off on the phy, in76 * case of suspend for instance. Theoretically, asserting individual77 * reset (like here) or global reset should be equivalent.78 */79 return reset_control_assert(phy_dev->rstport);80}81 82static const struct phy_ops stih407_usb2_picophy_data = {83 .init = stih407_usb2_init_port,84 .exit = stih407_usb2_exit_port,85 .owner = THIS_MODULE,86};87 88static int stih407_usb2_picophy_probe(struct platform_device *pdev)89{90 struct stih407_usb2_picophy *phy_dev;91 struct device *dev = &pdev->dev;92 struct device_node *np = dev->of_node;93 struct phy_provider *phy_provider;94 struct phy *phy;95 int ret;96 97 phy_dev = devm_kzalloc(dev, sizeof(*phy_dev), GFP_KERNEL);98 if (!phy_dev)99 return -ENOMEM;100 101 phy_dev->dev = dev;102 dev_set_drvdata(dev, phy_dev);103 104 phy_dev->rstc = devm_reset_control_get_shared(dev, "global");105 if (IS_ERR(phy_dev->rstc)) {106 dev_err(dev, "failed to ctrl picoPHY reset\n");107 return PTR_ERR(phy_dev->rstc);108 }109 110 phy_dev->rstport = devm_reset_control_get_exclusive(dev, "port");111 if (IS_ERR(phy_dev->rstport)) {112 dev_err(dev, "failed to ctrl picoPHY reset\n");113 return PTR_ERR(phy_dev->rstport);114 }115 116 /* Reset port by default: only deassert it in phy init */117 reset_control_assert(phy_dev->rstport);118 119 phy_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");120 if (IS_ERR(phy_dev->regmap)) {121 dev_err(dev, "No syscfg phandle specified\n");122 return PTR_ERR(phy_dev->regmap);123 }124 125 ret = of_property_read_u32_index(np, "st,syscfg", PHYPARAM_REG,126 &phy_dev->param);127 if (ret) {128 dev_err(dev, "can't get phyparam offset (%d)\n", ret);129 return ret;130 }131 132 ret = of_property_read_u32_index(np, "st,syscfg", PHYCTRL_REG,133 &phy_dev->ctrl);134 if (ret) {135 dev_err(dev, "can't get phyctrl offset (%d)\n", ret);136 return ret;137 }138 139 phy = devm_phy_create(dev, NULL, &stih407_usb2_picophy_data);140 if (IS_ERR(phy)) {141 dev_err(dev, "failed to create Display Port PHY\n");142 return PTR_ERR(phy);143 }144 145 phy_dev->phy = phy;146 phy_set_drvdata(phy, phy_dev);147 148 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);149 if (IS_ERR(phy_provider))150 return PTR_ERR(phy_provider);151 152 dev_info(dev, "STiH407 USB Generic picoPHY driver probed!");153 154 return 0;155}156 157static const struct of_device_id stih407_usb2_picophy_of_match[] = {158 { .compatible = "st,stih407-usb2-phy" },159 { /*sentinel */ },160};161 162MODULE_DEVICE_TABLE(of, stih407_usb2_picophy_of_match);163 164static struct platform_driver stih407_usb2_picophy_driver = {165 .probe = stih407_usb2_picophy_probe,166 .driver = {167 .name = "stih407-usb-genphy",168 .of_match_table = stih407_usb2_picophy_of_match,169 }170};171 172module_platform_driver(stih407_usb2_picophy_driver);173 174MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");175MODULE_DESCRIPTION("STMicroelectronics Generic picoPHY driver for STiH407");176MODULE_LICENSE("GPL v2");177