1 /* 2 * phy-keystone - USB PHY, talking to dwc3 controller in Keystone. 3 * 4 * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * Author: WingMan Kwok <w-kwok2@ti.com> 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 */ 18 19 #include <linux/module.h> 20 #include <linux/platform_device.h> 21 #include <linux/usb/usb_phy_generic.h> 22 #include <linux/io.h> 23 #include <linux/of.h> 24 25 #include "phy-generic.h" 26 27 /* USB PHY control register offsets */ 28 #define USB_PHY_CTL_UTMI 0x0000 29 #define USB_PHY_CTL_PIPE 0x0004 30 #define USB_PHY_CTL_PARAM_1 0x0008 31 #define USB_PHY_CTL_PARAM_2 0x000c 32 #define USB_PHY_CTL_CLOCK 0x0010 33 #define USB_PHY_CTL_PLL 0x0014 34 35 #define PHY_REF_SSP_EN BIT(29) 36 37 struct keystone_usbphy { 38 struct usb_phy_generic usb_phy_gen; 39 void __iomem *phy_ctrl; 40 }; 41 42 static inline u32 keystone_usbphy_readl(void __iomem *base, u32 offset) 43 { 44 return readl(base + offset); 45 } 46 47 static inline void keystone_usbphy_writel(void __iomem *base, 48 u32 offset, u32 value) 49 { 50 writel(value, base + offset); 51 } 52 53 static int keystone_usbphy_init(struct usb_phy *phy) 54 { 55 struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev); 56 u32 val; 57 58 val = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK); 59 keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK, 60 val | PHY_REF_SSP_EN); 61 return 0; 62 } 63 64 static void keystone_usbphy_shutdown(struct usb_phy *phy) 65 { 66 struct keystone_usbphy *k_phy = dev_get_drvdata(phy->dev); 67 u32 val; 68 69 val = keystone_usbphy_readl(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK); 70 keystone_usbphy_writel(k_phy->phy_ctrl, USB_PHY_CTL_CLOCK, 71 val &= ~PHY_REF_SSP_EN); 72 } 73 74 static int keystone_usbphy_probe(struct platform_device *pdev) 75 { 76 struct device *dev = &pdev->dev; 77 struct keystone_usbphy *k_phy; 78 struct resource *res; 79 int ret; 80 81 k_phy = devm_kzalloc(dev, sizeof(*k_phy), GFP_KERNEL); 82 if (!k_phy) 83 return -ENOMEM; 84 85 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 86 k_phy->phy_ctrl = devm_ioremap_resource(dev, res); 87 if (IS_ERR(k_phy->phy_ctrl)) 88 return PTR_ERR(k_phy->phy_ctrl); 89 90 ret = usb_phy_gen_create_phy(dev, &k_phy->usb_phy_gen, NULL); 91 if (ret) 92 return ret; 93 94 k_phy->usb_phy_gen.phy.init = keystone_usbphy_init; 95 k_phy->usb_phy_gen.phy.shutdown = keystone_usbphy_shutdown; 96 97 platform_set_drvdata(pdev, k_phy); 98 99 return usb_add_phy_dev(&k_phy->usb_phy_gen.phy); 100 } 101 102 static int keystone_usbphy_remove(struct platform_device *pdev) 103 { 104 struct keystone_usbphy *k_phy = platform_get_drvdata(pdev); 105 106 usb_remove_phy(&k_phy->usb_phy_gen.phy); 107 108 return 0; 109 } 110 111 static const struct of_device_id keystone_usbphy_ids[] = { 112 { .compatible = "ti,keystone-usbphy" }, 113 { } 114 }; 115 MODULE_DEVICE_TABLE(of, keystone_usbphy_ids); 116 117 static struct platform_driver keystone_usbphy_driver = { 118 .probe = keystone_usbphy_probe, 119 .remove = keystone_usbphy_remove, 120 .driver = { 121 .name = "keystone-usbphy", 122 .of_match_table = keystone_usbphy_ids, 123 }, 124 }; 125 126 module_platform_driver(keystone_usbphy_driver); 127 128 MODULE_ALIAS("platform:keystone-usbphy"); 129 MODULE_AUTHOR("Texas Instruments Inc."); 130 MODULE_DESCRIPTION("Keystone USB phy driver"); 131 MODULE_LICENSE("GPL v2"); 132