1 /* 2 * Renesas R-Car Gen3 for USB3.0 PHY driver 3 * 4 * Copyright (C) 2017 Renesas Electronics Corporation 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 #include <linux/clk.h> 12 #include <linux/delay.h> 13 #include <linux/io.h> 14 #include <linux/module.h> 15 #include <linux/of.h> 16 #include <linux/phy/phy.h> 17 #include <linux/platform_device.h> 18 #include <linux/pm_runtime.h> 19 20 #define USB30_CLKSET0 0x034 21 #define USB30_CLKSET1 0x036 22 #define USB30_SSC_SET 0x038 23 #define USB30_PHY_ENABLE 0x060 24 #define USB30_VBUS_EN 0x064 25 26 /* USB30_CLKSET0 */ 27 #define CLKSET0_PRIVATE 0x05c0 28 #define CLKSET0_USB30_FSEL_USB_EXTAL 0x0002 29 30 /* USB30_CLKSET1 */ 31 #define CLKSET1_USB30_PLL_MULTI_SHIFT 6 32 #define CLKSET1_USB30_PLL_MULTI_USB_EXTAL (0x64 << \ 33 CLKSET1_USB30_PLL_MULTI_SHIFT) 34 #define CLKSET1_PHYRESET BIT(4) /* 1: reset */ 35 #define CLKSET1_REF_CLKDIV BIT(3) /* 1: USB_EXTAL */ 36 #define CLKSET1_PRIVATE_2_1 BIT(1) /* Write B'01 */ 37 #define CLKSET1_REF_CLK_SEL BIT(0) /* 1: USB3S0_CLK_P */ 38 39 /* USB30_SSC_SET */ 40 #define SSC_SET_SSC_EN BIT(12) 41 #define SSC_SET_RANGE_SHIFT 9 42 #define SSC_SET_RANGE_4980 (0x0 << SSC_SET_RANGE_SHIFT) 43 #define SSC_SET_RANGE_4492 (0x1 << SSC_SET_RANGE_SHIFT) 44 #define SSC_SET_RANGE_4003 (0x2 << SSC_SET_RANGE_SHIFT) 45 46 /* USB30_PHY_ENABLE */ 47 #define PHY_ENABLE_RESET_EN BIT(4) 48 49 /* USB30_VBUS_EN */ 50 #define VBUS_EN_VBUS_EN BIT(1) 51 52 struct rcar_gen3_usb3 { 53 void __iomem *base; 54 struct phy *phy; 55 u32 ssc_range; 56 bool usb3s_clk; 57 bool usb_extal; 58 }; 59 60 static void write_clkset1_for_usb_extal(struct rcar_gen3_usb3 *r, bool reset) 61 { 62 u16 val = CLKSET1_USB30_PLL_MULTI_USB_EXTAL | 63 CLKSET1_REF_CLKDIV | CLKSET1_PRIVATE_2_1; 64 65 if (reset) 66 val |= CLKSET1_PHYRESET; 67 68 writew(val, r->base + USB30_CLKSET1); 69 } 70 71 static void rcar_gen3_phy_usb3_enable_ssc(struct rcar_gen3_usb3 *r) 72 { 73 u16 val = SSC_SET_SSC_EN; 74 75 switch (r->ssc_range) { 76 case 4980: 77 val |= SSC_SET_RANGE_4980; 78 break; 79 case 4492: 80 val |= SSC_SET_RANGE_4492; 81 break; 82 case 4003: 83 val |= SSC_SET_RANGE_4003; 84 break; 85 default: 86 dev_err(&r->phy->dev, "%s: unsupported range (%x)\n", __func__, 87 r->ssc_range); 88 return; 89 } 90 91 writew(val, r->base + USB30_SSC_SET); 92 } 93 94 static void rcar_gen3_phy_usb3_select_usb_extal(struct rcar_gen3_usb3 *r) 95 { 96 write_clkset1_for_usb_extal(r, false); 97 if (r->ssc_range) 98 rcar_gen3_phy_usb3_enable_ssc(r); 99 writew(CLKSET0_PRIVATE | CLKSET0_USB30_FSEL_USB_EXTAL, 100 r->base + USB30_CLKSET0); 101 writew(PHY_ENABLE_RESET_EN, r->base + USB30_PHY_ENABLE); 102 write_clkset1_for_usb_extal(r, true); 103 usleep_range(10, 20); 104 write_clkset1_for_usb_extal(r, false); 105 } 106 107 static int rcar_gen3_phy_usb3_init(struct phy *p) 108 { 109 struct rcar_gen3_usb3 *r = phy_get_drvdata(p); 110 111 dev_vdbg(&r->phy->dev, "%s: enter (%d, %d, %d)\n", __func__, 112 r->usb3s_clk, r->usb_extal, r->ssc_range); 113 114 if (!r->usb3s_clk && r->usb_extal) 115 rcar_gen3_phy_usb3_select_usb_extal(r); 116 117 /* Enables VBUS detection anyway */ 118 writew(VBUS_EN_VBUS_EN, r->base + USB30_VBUS_EN); 119 120 return 0; 121 } 122 123 static const struct phy_ops rcar_gen3_phy_usb3_ops = { 124 .init = rcar_gen3_phy_usb3_init, 125 .owner = THIS_MODULE, 126 }; 127 128 static const struct of_device_id rcar_gen3_phy_usb3_match_table[] = { 129 { .compatible = "renesas,rcar-gen3-usb3-phy" }, 130 { } 131 }; 132 MODULE_DEVICE_TABLE(of, rcar_gen3_phy_usb3_match_table); 133 134 static int rcar_gen3_phy_usb3_probe(struct platform_device *pdev) 135 { 136 struct device *dev = &pdev->dev; 137 struct rcar_gen3_usb3 *r; 138 struct phy_provider *provider; 139 struct resource *res; 140 int ret = 0; 141 struct clk *clk; 142 143 if (!dev->of_node) { 144 dev_err(dev, "This driver needs device tree\n"); 145 return -EINVAL; 146 } 147 148 r = devm_kzalloc(dev, sizeof(*r), GFP_KERNEL); 149 if (!r) 150 return -ENOMEM; 151 152 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 153 r->base = devm_ioremap_resource(dev, res); 154 if (IS_ERR(r->base)) 155 return PTR_ERR(r->base); 156 157 clk = devm_clk_get(dev, "usb3s_clk"); 158 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) { 159 r->usb3s_clk = !!clk_get_rate(clk); 160 clk_disable_unprepare(clk); 161 } 162 clk = devm_clk_get(dev, "usb_extal"); 163 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) { 164 r->usb_extal = !!clk_get_rate(clk); 165 clk_disable_unprepare(clk); 166 } 167 168 if (!r->usb3s_clk && !r->usb_extal) { 169 dev_err(dev, "This driver needs usb3s_clk and/or usb_extal\n"); 170 ret = -EINVAL; 171 goto error; 172 } 173 174 /* 175 * devm_phy_create() will call pm_runtime_enable(&phy->dev); 176 * And then, phy-core will manage runtime pm for this device. 177 */ 178 pm_runtime_enable(dev); 179 180 r->phy = devm_phy_create(dev, NULL, &rcar_gen3_phy_usb3_ops); 181 if (IS_ERR(r->phy)) { 182 dev_err(dev, "Failed to create USB3 PHY\n"); 183 ret = PTR_ERR(r->phy); 184 goto error; 185 } 186 187 of_property_read_u32(dev->of_node, "renesas,ssc-range", &r->ssc_range); 188 189 platform_set_drvdata(pdev, r); 190 phy_set_drvdata(r->phy, r); 191 192 provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); 193 if (IS_ERR(provider)) { 194 dev_err(dev, "Failed to register PHY provider\n"); 195 ret = PTR_ERR(provider); 196 goto error; 197 } 198 199 return 0; 200 201 error: 202 pm_runtime_disable(dev); 203 204 return ret; 205 } 206 207 static int rcar_gen3_phy_usb3_remove(struct platform_device *pdev) 208 { 209 pm_runtime_disable(&pdev->dev); 210 211 return 0; 212 }; 213 214 static struct platform_driver rcar_gen3_phy_usb3_driver = { 215 .driver = { 216 .name = "phy_rcar_gen3_usb3", 217 .of_match_table = rcar_gen3_phy_usb3_match_table, 218 }, 219 .probe = rcar_gen3_phy_usb3_probe, 220 .remove = rcar_gen3_phy_usb3_remove, 221 }; 222 module_platform_driver(rcar_gen3_phy_usb3_driver); 223 224 MODULE_LICENSE("GPL v2"); 225 MODULE_DESCRIPTION("Renesas R-Car Gen3 USB 3.0 PHY"); 226 MODULE_AUTHOR("Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>"); 227