1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Lantiq XWAY SoC RCU module based USB 1.1/2.0 PHY driver 4 * 5 * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com> 6 * Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de> 7 */ 8 9 #include <linux/clk.h> 10 #include <linux/delay.h> 11 #include <linux/mfd/syscon.h> 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/of_address.h> 15 #include <linux/of_device.h> 16 #include <linux/phy/phy.h> 17 #include <linux/platform_device.h> 18 #include <linux/property.h> 19 #include <linux/regmap.h> 20 #include <linux/reset.h> 21 22 /* Transmitter HS Pre-Emphasis Enable */ 23 #define RCU_CFG1_TX_PEE BIT(0) 24 /* Disconnect Threshold */ 25 #define RCU_CFG1_DIS_THR_MASK 0x00038000 26 #define RCU_CFG1_DIS_THR_SHIFT 15 27 28 struct ltq_rcu_usb2_bits { 29 u8 hostmode; 30 u8 slave_endianness; 31 u8 host_endianness; 32 bool have_ana_cfg; 33 }; 34 35 struct ltq_rcu_usb2_priv { 36 struct regmap *regmap; 37 unsigned int phy_reg_offset; 38 unsigned int ana_cfg1_reg_offset; 39 const struct ltq_rcu_usb2_bits *reg_bits; 40 struct device *dev; 41 struct phy *phy; 42 struct clk *phy_gate_clk; 43 struct reset_control *ctrl_reset; 44 struct reset_control *phy_reset; 45 }; 46 47 static const struct ltq_rcu_usb2_bits xway_rcu_usb2_reg_bits = { 48 .hostmode = 11, 49 .slave_endianness = 9, 50 .host_endianness = 10, 51 .have_ana_cfg = false, 52 }; 53 54 static const struct ltq_rcu_usb2_bits xrx100_rcu_usb2_reg_bits = { 55 .hostmode = 11, 56 .slave_endianness = 17, 57 .host_endianness = 10, 58 .have_ana_cfg = false, 59 }; 60 61 static const struct ltq_rcu_usb2_bits xrx200_rcu_usb2_reg_bits = { 62 .hostmode = 11, 63 .slave_endianness = 9, 64 .host_endianness = 10, 65 .have_ana_cfg = true, 66 }; 67 68 static const struct of_device_id ltq_rcu_usb2_phy_of_match[] = { 69 { 70 .compatible = "lantiq,ase-usb2-phy", 71 .data = &xway_rcu_usb2_reg_bits, 72 }, 73 { 74 .compatible = "lantiq,danube-usb2-phy", 75 .data = &xway_rcu_usb2_reg_bits, 76 }, 77 { 78 .compatible = "lantiq,xrx100-usb2-phy", 79 .data = &xrx100_rcu_usb2_reg_bits, 80 }, 81 { 82 .compatible = "lantiq,xrx200-usb2-phy", 83 .data = &xrx200_rcu_usb2_reg_bits, 84 }, 85 { 86 .compatible = "lantiq,xrx300-usb2-phy", 87 .data = &xrx200_rcu_usb2_reg_bits, 88 }, 89 { }, 90 }; 91 MODULE_DEVICE_TABLE(of, ltq_rcu_usb2_phy_of_match); 92 93 static int ltq_rcu_usb2_phy_init(struct phy *phy) 94 { 95 struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy); 96 97 if (priv->reg_bits->have_ana_cfg) { 98 regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset, 99 RCU_CFG1_TX_PEE, RCU_CFG1_TX_PEE); 100 regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset, 101 RCU_CFG1_DIS_THR_MASK, 7 << RCU_CFG1_DIS_THR_SHIFT); 102 } 103 104 /* Configure core to host mode */ 105 regmap_update_bits(priv->regmap, priv->phy_reg_offset, 106 BIT(priv->reg_bits->hostmode), 0); 107 108 /* Select DMA endianness (Host-endian: big-endian) */ 109 regmap_update_bits(priv->regmap, priv->phy_reg_offset, 110 BIT(priv->reg_bits->slave_endianness), 0); 111 regmap_update_bits(priv->regmap, priv->phy_reg_offset, 112 BIT(priv->reg_bits->host_endianness), 113 BIT(priv->reg_bits->host_endianness)); 114 115 return 0; 116 } 117 118 static int ltq_rcu_usb2_phy_power_on(struct phy *phy) 119 { 120 struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy); 121 struct device *dev = priv->dev; 122 int ret; 123 124 reset_control_deassert(priv->phy_reset); 125 126 ret = clk_prepare_enable(priv->phy_gate_clk); 127 if (ret) { 128 dev_err(dev, "failed to enable PHY gate\n"); 129 return ret; 130 } 131 132 /* 133 * at least the xrx200 usb2 phy requires some extra time to be 134 * operational after enabling the clock 135 */ 136 usleep_range(100, 200); 137 138 return ret; 139 } 140 141 static int ltq_rcu_usb2_phy_power_off(struct phy *phy) 142 { 143 struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy); 144 145 reset_control_assert(priv->phy_reset); 146 147 clk_disable_unprepare(priv->phy_gate_clk); 148 149 return 0; 150 } 151 152 static const struct phy_ops ltq_rcu_usb2_phy_ops = { 153 .init = ltq_rcu_usb2_phy_init, 154 .power_on = ltq_rcu_usb2_phy_power_on, 155 .power_off = ltq_rcu_usb2_phy_power_off, 156 .owner = THIS_MODULE, 157 }; 158 159 static int ltq_rcu_usb2_of_parse(struct ltq_rcu_usb2_priv *priv, 160 struct platform_device *pdev) 161 { 162 struct device *dev = priv->dev; 163 const __be32 *offset; 164 165 priv->reg_bits = of_device_get_match_data(dev); 166 167 priv->regmap = syscon_node_to_regmap(dev->of_node->parent); 168 if (IS_ERR(priv->regmap)) { 169 dev_err(dev, "Failed to lookup RCU regmap\n"); 170 return PTR_ERR(priv->regmap); 171 } 172 173 offset = of_get_address(dev->of_node, 0, NULL, NULL); 174 if (!offset) { 175 dev_err(dev, "Failed to get RCU PHY reg offset\n"); 176 return -ENOENT; 177 } 178 priv->phy_reg_offset = __be32_to_cpu(*offset); 179 180 if (priv->reg_bits->have_ana_cfg) { 181 offset = of_get_address(dev->of_node, 1, NULL, NULL); 182 if (!offset) { 183 dev_err(dev, "Failed to get RCU ANA CFG1 reg offset\n"); 184 return -ENOENT; 185 } 186 priv->ana_cfg1_reg_offset = __be32_to_cpu(*offset); 187 } 188 189 priv->phy_gate_clk = devm_clk_get(dev, "phy"); 190 if (IS_ERR(priv->phy_gate_clk)) { 191 dev_err(dev, "Unable to get USB phy gate clk\n"); 192 return PTR_ERR(priv->phy_gate_clk); 193 } 194 195 priv->ctrl_reset = devm_reset_control_get_shared(dev, "ctrl"); 196 if (IS_ERR(priv->ctrl_reset)) { 197 if (PTR_ERR(priv->ctrl_reset) != -EPROBE_DEFER) 198 dev_err(dev, "failed to get 'ctrl' reset\n"); 199 return PTR_ERR(priv->ctrl_reset); 200 } 201 202 priv->phy_reset = devm_reset_control_get_optional(dev, "phy"); 203 204 return PTR_ERR_OR_ZERO(priv->phy_reset); 205 } 206 207 static int ltq_rcu_usb2_phy_probe(struct platform_device *pdev) 208 { 209 struct device *dev = &pdev->dev; 210 struct ltq_rcu_usb2_priv *priv; 211 struct phy_provider *provider; 212 int ret; 213 214 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 215 if (!priv) 216 return -ENOMEM; 217 218 priv->dev = dev; 219 220 ret = ltq_rcu_usb2_of_parse(priv, pdev); 221 if (ret) 222 return ret; 223 224 /* Reset USB core through reset controller */ 225 reset_control_deassert(priv->ctrl_reset); 226 227 reset_control_assert(priv->phy_reset); 228 229 priv->phy = devm_phy_create(dev, dev->of_node, <q_rcu_usb2_phy_ops); 230 if (IS_ERR(priv->phy)) { 231 dev_err(dev, "failed to create PHY\n"); 232 return PTR_ERR(priv->phy); 233 } 234 235 phy_set_drvdata(priv->phy, priv); 236 237 provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); 238 if (IS_ERR(provider)) 239 return PTR_ERR(provider); 240 241 dev_set_drvdata(priv->dev, priv); 242 return 0; 243 } 244 245 static struct platform_driver ltq_rcu_usb2_phy_driver = { 246 .probe = ltq_rcu_usb2_phy_probe, 247 .driver = { 248 .name = "lantiq-rcu-usb2-phy", 249 .of_match_table = ltq_rcu_usb2_phy_of_match, 250 } 251 }; 252 module_platform_driver(ltq_rcu_usb2_phy_driver); 253 254 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>"); 255 MODULE_DESCRIPTION("Lantiq XWAY USB2 PHY driver"); 256 MODULE_LICENSE("GPL v2"); 257