1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * SpacemiT K1 USB 2.0 PHY driver 4 * 5 * Copyright (C) 2025 SpacemiT (Hangzhou) Technology Co. Ltd 6 * Copyright (C) 2025 Ze Huang <huang.ze@linux.dev> 7 */ 8 9 #include <linux/bitfield.h> 10 #include <linux/clk.h> 11 #include <linux/iopoll.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 #include <linux/usb/of.h> 15 16 #define PHY_RST_MODE_CTRL 0x04 17 #define PHY_PLL_RDY BIT(0) 18 #define PHY_CLK_CDR_EN BIT(1) 19 #define PHY_CLK_PLL_EN BIT(2) 20 #define PHY_CLK_MAC_EN BIT(3) 21 #define PHY_MAC_RSTN BIT(5) 22 #define PHY_CDR_RSTN BIT(6) 23 #define PHY_PLL_RSTN BIT(7) 24 /* 25 * hs line state sel (Bit 13): 26 * - 1 (Default): Internal HS line state is set to 01 when usb_hs_tx_en is valid. 27 * - 0: Internal HS line state is always driven by usb_hs_lstate. 28 * 29 * fs line state sel (Bit 14): 30 * - 1 (Default): FS line state is determined by the output data 31 * (usb_fs_datain/b). 32 * - 0: FS line state is always determined by the input data (dmo/dpo). 33 */ 34 #define PHY_HS_LINE_TX_MODE BIT(13) 35 #define PHY_FS_LINE_TX_MODE BIT(14) 36 37 #define PHY_INIT_MODE_BITS (PHY_FS_LINE_TX_MODE | PHY_HS_LINE_TX_MODE) 38 #define PHY_CLK_ENABLE_BITS (PHY_CLK_PLL_EN | PHY_CLK_CDR_EN | \ 39 PHY_CLK_MAC_EN) 40 #define PHY_DEASSERT_RST_BITS (PHY_PLL_RSTN | PHY_CDR_RSTN | \ 41 PHY_MAC_RSTN) 42 43 #define PHY_TX_HOST_CTRL 0x10 44 #define PHY_HST_DISC_AUTO_CLR BIT(2) /* autoclear hs host disc when re-connect */ 45 46 #define PHY_HSTXP_HW_CTRL 0x34 47 #define PHY_HSTXP_RSTN BIT(2) /* generate reset for clock hstxp */ 48 #define PHY_CLK_HSTXP_EN BIT(3) /* clock hstxp enable */ 49 #define PHY_HSTXP_MODE BIT(4) /* 0: force en_txp to be 1; 1: no force */ 50 51 #define PHY_PLL_DIV_CFG 0x98 52 #define PHY_FDIV_FRACT_8_15 GENMASK(7, 0) 53 #define PHY_FDIV_FRACT_16_19 GENMASK(11, 8) 54 #define PHY_FDIV_FRACT_20_21 BIT(12) /* fdiv_reg<21>, <20>, bit21 == bit20 */ 55 /* 56 * freq_sel<1:0> 57 * if ref clk freq=24.0MHz-->freq_sel<2:0> == 3b'001, then internal divider value == 80 58 */ 59 #define PHY_FDIV_FRACT_0_1 GENMASK(14, 13) 60 /* 61 * pll divider value selection 62 * 1: divider value will choose internal default value ,dependent on freq_sel<1:0> 63 * 0: divider value will be over ride by fdiv_reg<21:0> 64 */ 65 #define PHY_DIV_LOCAL_EN BIT(15) 66 67 #define PHY_SEL_FREQ_24MHZ 0x01 68 #define FDIV_REG_MASK (PHY_FDIV_FRACT_20_21 | PHY_FDIV_FRACT_16_19 | \ 69 PHY_FDIV_FRACT_8_15) 70 #define FDIV_REG_VAL 0x1ec4 /* 0x100 selects 24MHz, rest are default */ 71 72 #define K1_USB2PHY_RESET_TIME_MS 50 73 74 struct spacemit_usb2phy { 75 struct phy *phy; 76 struct clk *clk; 77 struct regmap *regmap_base; 78 }; 79 80 static const struct regmap_config phy_regmap_config = { 81 .reg_bits = 32, 82 .val_bits = 32, 83 .reg_stride = 4, 84 .max_register = 0x200, 85 }; 86 87 static int spacemit_usb2phy_init(struct phy *phy) 88 { 89 struct spacemit_usb2phy *sphy = phy_get_drvdata(phy); 90 struct regmap *map = sphy->regmap_base; 91 u32 val; 92 int ret; 93 94 ret = clk_enable(sphy->clk); 95 if (ret) { 96 dev_err(&phy->dev, "failed to enable clock\n"); 97 clk_disable(sphy->clk); 98 return ret; 99 } 100 101 /* 102 * make sure the usb controller is not under reset process before 103 * any configuration 104 */ 105 usleep_range(150, 200); 106 107 /* 24M ref clk */ 108 val = FIELD_PREP(FDIV_REG_MASK, FDIV_REG_VAL) | 109 FIELD_PREP(PHY_FDIV_FRACT_0_1, PHY_SEL_FREQ_24MHZ) | 110 PHY_DIV_LOCAL_EN; 111 regmap_write(map, PHY_PLL_DIV_CFG, val); 112 113 ret = regmap_read_poll_timeout(map, PHY_RST_MODE_CTRL, val, 114 (val & PHY_PLL_RDY), 115 500, K1_USB2PHY_RESET_TIME_MS * 1000); 116 if (ret) { 117 dev_err(&phy->dev, "wait PLLREADY timeout\n"); 118 clk_disable(sphy->clk); 119 return ret; 120 } 121 122 /* release usb2 phy internal reset and enable clock gating */ 123 val = (PHY_INIT_MODE_BITS | PHY_CLK_ENABLE_BITS | PHY_DEASSERT_RST_BITS); 124 regmap_write(map, PHY_RST_MODE_CTRL, val); 125 126 val = (PHY_HSTXP_RSTN | PHY_CLK_HSTXP_EN | PHY_HSTXP_MODE); 127 regmap_write(map, PHY_HSTXP_HW_CTRL, val); 128 129 /* auto clear host disc */ 130 regmap_update_bits(map, PHY_TX_HOST_CTRL, PHY_HST_DISC_AUTO_CLR, 131 PHY_HST_DISC_AUTO_CLR); 132 133 return 0; 134 } 135 136 static int spacemit_usb2phy_exit(struct phy *phy) 137 { 138 struct spacemit_usb2phy *sphy = phy_get_drvdata(phy); 139 140 clk_disable(sphy->clk); 141 142 return 0; 143 } 144 145 static const struct phy_ops spacemit_usb2phy_ops = { 146 .init = spacemit_usb2phy_init, 147 .exit = spacemit_usb2phy_exit, 148 .owner = THIS_MODULE, 149 }; 150 151 static int spacemit_usb2phy_probe(struct platform_device *pdev) 152 { 153 struct phy_provider *phy_provider; 154 struct device *dev = &pdev->dev; 155 struct spacemit_usb2phy *sphy; 156 void __iomem *base; 157 158 sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL); 159 if (!sphy) 160 return -ENOMEM; 161 162 sphy->clk = devm_clk_get_prepared(&pdev->dev, NULL); 163 if (IS_ERR(sphy->clk)) 164 return dev_err_probe(dev, PTR_ERR(sphy->clk), "Failed to get clock\n"); 165 166 base = devm_platform_ioremap_resource(pdev, 0); 167 if (IS_ERR(base)) 168 return PTR_ERR(base); 169 170 sphy->regmap_base = devm_regmap_init_mmio(dev, base, &phy_regmap_config); 171 if (IS_ERR(sphy->regmap_base)) 172 return dev_err_probe(dev, PTR_ERR(sphy->regmap_base), "Failed to init regmap\n"); 173 174 sphy->phy = devm_phy_create(dev, NULL, &spacemit_usb2phy_ops); 175 if (IS_ERR(sphy->phy)) 176 return dev_err_probe(dev, PTR_ERR(sphy->phy), "Failed to create phy\n"); 177 178 phy_set_drvdata(sphy->phy, sphy); 179 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); 180 181 return PTR_ERR_OR_ZERO(phy_provider); 182 } 183 184 static const struct of_device_id spacemit_usb2phy_dt_match[] = { 185 { .compatible = "spacemit,k1-usb2-phy", }, 186 { /* sentinel */ } 187 }; 188 MODULE_DEVICE_TABLE(of, spacemit_usb2phy_dt_match); 189 190 static struct platform_driver spacemit_usb2_phy_driver = { 191 .probe = spacemit_usb2phy_probe, 192 .driver = { 193 .name = "spacemit-usb2-phy", 194 .of_match_table = spacemit_usb2phy_dt_match, 195 }, 196 }; 197 module_platform_driver(spacemit_usb2_phy_driver); 198 199 MODULE_DESCRIPTION("Spacemit USB 2.0 PHY driver"); 200 MODULE_LICENSE("GPL"); 201