1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * ulpi.c - DesignWare USB3 Controller's ULPI PHY interface 4 * 5 * Copyright (C) 2015 Intel Corporation 6 * 7 * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> 8 */ 9 10 #include <linux/delay.h> 11 #include <linux/time64.h> 12 #include <linux/ulpi/regs.h> 13 #include <linux/ulpi/driver.h> 14 15 #include "core.h" 16 #include "io.h" 17 18 #define USB_VENDOR_MICROCHIP 0x0424 19 20 #define DWC3_ULPI_ADDR(a) \ 21 ((a >= ULPI_EXT_VENDOR_SPECIFIC) ? \ 22 DWC3_GUSB2PHYACC_ADDR(ULPI_ACCESS_EXTENDED) | \ 23 DWC3_GUSB2PHYACC_EXTEND_ADDR(a) : DWC3_GUSB2PHYACC_ADDR(a)) 24 25 #define DWC3_ULPI_BASE_DELAY DIV_ROUND_UP(NSEC_PER_SEC, 60000000L) 26 27 static int dwc3_ulpi_busyloop(struct dwc3 *dwc, u8 addr, bool read) 28 { 29 unsigned long ns = 5L * DWC3_ULPI_BASE_DELAY; 30 unsigned int count = 10000; 31 u32 reg; 32 33 if (addr >= ULPI_EXT_VENDOR_SPECIFIC) 34 ns += DWC3_ULPI_BASE_DELAY; 35 36 if (read) 37 ns += DWC3_ULPI_BASE_DELAY; 38 39 reg = dwc3_readl(dwc, DWC3_GUSB2PHYCFG(0)); 40 if (reg & DWC3_GUSB2PHYCFG_SUSPHY) 41 usleep_range(1000, 1200); 42 43 while (count--) { 44 ndelay(ns); 45 reg = dwc3_readl(dwc, DWC3_GUSB2PHYACC(0)); 46 if (reg & DWC3_GUSB2PHYACC_DONE) 47 return 0; 48 cpu_relax(); 49 } 50 51 return -ETIMEDOUT; 52 } 53 54 static int dwc3_ulpi_read(struct device *dev, u8 addr) 55 { 56 struct dwc3 *dwc = dev_get_drvdata(dev); 57 u32 reg; 58 int ret; 59 60 reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); 61 dwc3_writel(dwc, DWC3_GUSB2PHYACC(0), reg); 62 63 ret = dwc3_ulpi_busyloop(dwc, addr, true); 64 if (ret) 65 return ret; 66 67 reg = dwc3_readl(dwc, DWC3_GUSB2PHYACC(0)); 68 69 return DWC3_GUSB2PHYACC_DATA(reg); 70 } 71 72 static int dwc3_ulpi_write(struct device *dev, u8 addr, u8 val) 73 { 74 struct dwc3 *dwc = dev_get_drvdata(dev); 75 u32 reg; 76 77 reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); 78 reg |= DWC3_GUSB2PHYACC_WRITE | val; 79 dwc3_writel(dwc, DWC3_GUSB2PHYACC(0), reg); 80 81 return dwc3_ulpi_busyloop(dwc, addr, false); 82 } 83 84 static const struct ulpi_ops dwc3_ulpi_ops = { 85 .read = dwc3_ulpi_read, 86 .write = dwc3_ulpi_write, 87 }; 88 89 static void dwc3_ulpi_detect_config(struct dwc3 *dwc) 90 { 91 struct ulpi *ulpi = dwc->ulpi; 92 93 switch (ulpi->id.vendor) { 94 case USB_VENDOR_MICROCHIP: 95 switch (ulpi->id.product) { 96 case 0x0009: 97 /* Microchip USB3340 ULPI PHY */ 98 dwc->enable_usb2_transceiver_delay = true; 99 break; 100 default: 101 break; 102 } 103 break; 104 default: 105 break; 106 } 107 } 108 109 int dwc3_ulpi_init(struct dwc3 *dwc) 110 { 111 /* Register the interface */ 112 dwc->ulpi = ulpi_register_interface(dwc->dev, &dwc3_ulpi_ops); 113 if (IS_ERR(dwc->ulpi)) { 114 dev_err(dwc->dev, "failed to register ULPI interface"); 115 return PTR_ERR(dwc->ulpi); 116 } 117 118 dwc3_ulpi_detect_config(dwc); 119 120 return 0; 121 } 122 123 void dwc3_ulpi_exit(struct dwc3 *dwc) 124 { 125 if (dwc->ulpi) { 126 ulpi_unregister_interface(dwc->ulpi); 127 dwc->ulpi = NULL; 128 } 129 } 130