1 /* 2 * PHY driver for NXP LPC18xx/43xx internal USB OTG PHY 3 * 4 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 */ 11 12 #include <linux/clk.h> 13 #include <linux/err.h> 14 #include <linux/mfd/syscon.h> 15 #include <linux/module.h> 16 #include <linux/of.h> 17 #include <linux/phy/phy.h> 18 #include <linux/platform_device.h> 19 #include <linux/regmap.h> 20 21 /* USB OTG PHY register offset and bit in CREG */ 22 #define LPC18XX_CREG_CREG0 0x004 23 #define LPC18XX_CREG_CREG0_USB0PHY BIT(5) 24 25 struct lpc18xx_usb_otg_phy { 26 struct phy *phy; 27 struct clk *clk; 28 struct regmap *reg; 29 }; 30 31 static int lpc18xx_usb_otg_phy_init(struct phy *phy) 32 { 33 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy); 34 int ret; 35 36 /* The PHY must be clocked at 480 MHz */ 37 ret = clk_set_rate(lpc->clk, 480000000); 38 if (ret) 39 return ret; 40 41 return clk_prepare(lpc->clk); 42 } 43 44 static int lpc18xx_usb_otg_phy_exit(struct phy *phy) 45 { 46 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy); 47 48 clk_unprepare(lpc->clk); 49 50 return 0; 51 } 52 53 static int lpc18xx_usb_otg_phy_power_on(struct phy *phy) 54 { 55 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy); 56 int ret; 57 58 ret = clk_enable(lpc->clk); 59 if (ret) 60 return ret; 61 62 /* The bit in CREG is cleared to enable the PHY */ 63 return regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0, 64 LPC18XX_CREG_CREG0_USB0PHY, 0); 65 } 66 67 static int lpc18xx_usb_otg_phy_power_off(struct phy *phy) 68 { 69 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy); 70 int ret; 71 72 ret = regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0, 73 LPC18XX_CREG_CREG0_USB0PHY, 74 LPC18XX_CREG_CREG0_USB0PHY); 75 if (ret) 76 return ret; 77 78 clk_disable(lpc->clk); 79 80 return 0; 81 } 82 83 static const struct phy_ops lpc18xx_usb_otg_phy_ops = { 84 .init = lpc18xx_usb_otg_phy_init, 85 .exit = lpc18xx_usb_otg_phy_exit, 86 .power_on = lpc18xx_usb_otg_phy_power_on, 87 .power_off = lpc18xx_usb_otg_phy_power_off, 88 .owner = THIS_MODULE, 89 }; 90 91 static int lpc18xx_usb_otg_phy_probe(struct platform_device *pdev) 92 { 93 struct phy_provider *phy_provider; 94 struct lpc18xx_usb_otg_phy *lpc; 95 96 lpc = devm_kzalloc(&pdev->dev, sizeof(*lpc), GFP_KERNEL); 97 if (!lpc) 98 return -ENOMEM; 99 100 lpc->reg = syscon_node_to_regmap(pdev->dev.of_node->parent); 101 if (IS_ERR(lpc->reg)) { 102 dev_err(&pdev->dev, "failed to get syscon\n"); 103 return PTR_ERR(lpc->reg); 104 } 105 106 lpc->clk = devm_clk_get(&pdev->dev, NULL); 107 if (IS_ERR(lpc->clk)) { 108 dev_err(&pdev->dev, "failed to get clock\n"); 109 return PTR_ERR(lpc->clk); 110 } 111 112 lpc->phy = devm_phy_create(&pdev->dev, NULL, &lpc18xx_usb_otg_phy_ops); 113 if (IS_ERR(lpc->phy)) { 114 dev_err(&pdev->dev, "failed to create PHY\n"); 115 return PTR_ERR(lpc->phy); 116 } 117 118 phy_set_drvdata(lpc->phy, lpc); 119 120 phy_provider = devm_of_phy_provider_register(&pdev->dev, 121 of_phy_simple_xlate); 122 123 return PTR_ERR_OR_ZERO(phy_provider); 124 } 125 126 static const struct of_device_id lpc18xx_usb_otg_phy_match[] = { 127 { .compatible = "nxp,lpc1850-usb-otg-phy" }, 128 { } 129 }; 130 MODULE_DEVICE_TABLE(of, lpc18xx_usb_otg_phy_match); 131 132 static struct platform_driver lpc18xx_usb_otg_phy_driver = { 133 .probe = lpc18xx_usb_otg_phy_probe, 134 .driver = { 135 .name = "lpc18xx-usb-otg-phy", 136 .of_match_table = lpc18xx_usb_otg_phy_match, 137 }, 138 }; 139 module_platform_driver(lpc18xx_usb_otg_phy_driver); 140 141 MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>"); 142 MODULE_DESCRIPTION("NXP LPC18xx/43xx USB OTG PHY driver"); 143 MODULE_LICENSE("GPL v2"); 144