1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Intel LGM USB PHY driver 4 * 5 * Copyright (C) 2020 Intel Corporation. 6 */ 7 8 #include <linux/bitfield.h> 9 #include <linux/delay.h> 10 #include <linux/iopoll.h> 11 #include <linux/module.h> 12 #include <linux/of.h> 13 #include <linux/platform_device.h> 14 #include <linux/regulator/consumer.h> 15 #include <linux/reset.h> 16 #include <linux/usb/phy.h> 17 #include <linux/workqueue.h> 18 19 #define CTRL1_OFFSET 0x14 20 #define SRAM_EXT_LD_DONE BIT(25) 21 #define SRAM_INIT_DONE BIT(26) 22 23 #define TCPC_OFFSET 0x1014 24 #define TCPC_MUX_CTL GENMASK(1, 0) 25 #define MUX_NC 0 26 #define MUX_USB 1 27 #define MUX_DP 2 28 #define MUX_USBDP 3 29 #define TCPC_FLIPPED BIT(2) 30 #define TCPC_LOW_POWER_EN BIT(3) 31 #define TCPC_VALID BIT(4) 32 #define TCPC_CONN \ 33 (TCPC_VALID | FIELD_PREP(TCPC_MUX_CTL, MUX_USB)) 34 #define TCPC_DISCONN \ 35 (TCPC_VALID | FIELD_PREP(TCPC_MUX_CTL, MUX_NC) | TCPC_LOW_POWER_EN) 36 37 static const char *const PHY_RESETS[] = { "phy31", "phy", }; 38 static const char *const CTL_RESETS[] = { "apb", "ctrl", }; 39 40 struct tca_apb { 41 struct reset_control *resets[ARRAY_SIZE(PHY_RESETS)]; 42 struct regulator *vbus; 43 struct work_struct wk; 44 struct usb_phy phy; 45 46 bool regulator_enabled; 47 bool phy_initialized; 48 bool connected; 49 }; 50 51 static int get_flipped(struct tca_apb *ta, bool *flipped) 52 { 53 union extcon_property_value property; 54 int ret; 55 56 ret = extcon_get_property(ta->phy.edev, EXTCON_USB_HOST, 57 EXTCON_PROP_USB_TYPEC_POLARITY, &property); 58 if (ret) { 59 dev_err(ta->phy.dev, "no polarity property from extcon\n"); 60 return ret; 61 } 62 63 *flipped = property.intval; 64 65 return 0; 66 } 67 68 static int phy_init(struct usb_phy *phy) 69 { 70 struct tca_apb *ta = container_of(phy, struct tca_apb, phy); 71 void __iomem *ctrl1 = phy->io_priv + CTRL1_OFFSET; 72 int val, ret, i; 73 74 if (ta->phy_initialized) 75 return 0; 76 77 for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) 78 reset_control_deassert(ta->resets[i]); 79 80 ret = readl_poll_timeout(ctrl1, val, val & SRAM_INIT_DONE, 10, 10 * 1000); 81 if (ret) { 82 dev_err(ta->phy.dev, "SRAM init failed, 0x%x\n", val); 83 return ret; 84 } 85 86 writel(readl(ctrl1) | SRAM_EXT_LD_DONE, ctrl1); 87 88 ta->phy_initialized = true; 89 if (!ta->phy.edev) { 90 writel(TCPC_CONN, ta->phy.io_priv + TCPC_OFFSET); 91 return phy->set_vbus(phy, true); 92 } 93 94 schedule_work(&ta->wk); 95 96 return ret; 97 } 98 99 static void phy_shutdown(struct usb_phy *phy) 100 { 101 struct tca_apb *ta = container_of(phy, struct tca_apb, phy); 102 int i; 103 104 if (!ta->phy_initialized) 105 return; 106 107 ta->phy_initialized = false; 108 flush_work(&ta->wk); 109 ta->phy.set_vbus(&ta->phy, false); 110 111 ta->connected = false; 112 writel(TCPC_DISCONN, ta->phy.io_priv + TCPC_OFFSET); 113 114 for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) 115 reset_control_assert(ta->resets[i]); 116 } 117 118 static int phy_set_vbus(struct usb_phy *phy, int on) 119 { 120 struct tca_apb *ta = container_of(phy, struct tca_apb, phy); 121 int ret; 122 123 if (!!on == ta->regulator_enabled) 124 return 0; 125 126 if (on) 127 ret = regulator_enable(ta->vbus); 128 else 129 ret = regulator_disable(ta->vbus); 130 131 if (!ret) 132 ta->regulator_enabled = on; 133 134 dev_dbg(ta->phy.dev, "set vbus: %d\n", on); 135 return ret; 136 } 137 138 static void tca_work(struct work_struct *work) 139 { 140 struct tca_apb *ta = container_of(work, struct tca_apb, wk); 141 bool connected; 142 bool flipped = false; 143 u32 val; 144 int ret; 145 146 ret = get_flipped(ta, &flipped); 147 if (ret) 148 return; 149 150 connected = extcon_get_state(ta->phy.edev, EXTCON_USB_HOST); 151 if (connected == ta->connected) 152 return; 153 154 ta->connected = connected; 155 if (connected) { 156 val = TCPC_CONN; 157 if (flipped) 158 val |= TCPC_FLIPPED; 159 dev_dbg(ta->phy.dev, "connected%s\n", flipped ? " flipped" : ""); 160 } else { 161 val = TCPC_DISCONN; 162 dev_dbg(ta->phy.dev, "disconnected\n"); 163 } 164 165 writel(val, ta->phy.io_priv + TCPC_OFFSET); 166 167 ret = ta->phy.set_vbus(&ta->phy, connected); 168 if (ret) 169 dev_err(ta->phy.dev, "failed to set VBUS\n"); 170 } 171 172 static int id_notifier(struct notifier_block *nb, unsigned long event, void *ptr) 173 { 174 struct tca_apb *ta = container_of(nb, struct tca_apb, phy.id_nb); 175 176 if (ta->phy_initialized) 177 schedule_work(&ta->wk); 178 179 return NOTIFY_DONE; 180 } 181 182 static int vbus_notifier(struct notifier_block *nb, unsigned long evnt, void *ptr) 183 { 184 return NOTIFY_DONE; 185 } 186 187 static int phy_probe(struct platform_device *pdev) 188 { 189 struct reset_control *resets[ARRAY_SIZE(CTL_RESETS)]; 190 struct device *dev = &pdev->dev; 191 struct usb_phy *phy; 192 struct tca_apb *ta; 193 int i; 194 195 ta = devm_kzalloc(dev, sizeof(*ta), GFP_KERNEL); 196 if (!ta) 197 return -ENOMEM; 198 199 platform_set_drvdata(pdev, ta); 200 INIT_WORK(&ta->wk, tca_work); 201 202 phy = &ta->phy; 203 phy->dev = dev; 204 phy->label = dev_name(dev); 205 phy->type = USB_PHY_TYPE_USB3; 206 phy->init = phy_init; 207 phy->shutdown = phy_shutdown; 208 phy->set_vbus = phy_set_vbus; 209 phy->id_nb.notifier_call = id_notifier; 210 phy->vbus_nb.notifier_call = vbus_notifier; 211 212 phy->io_priv = devm_platform_ioremap_resource(pdev, 0); 213 if (IS_ERR(phy->io_priv)) 214 return PTR_ERR(phy->io_priv); 215 216 ta->vbus = devm_regulator_get(dev, "vbus"); 217 if (IS_ERR(ta->vbus)) 218 return PTR_ERR(ta->vbus); 219 220 for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) { 221 resets[i] = devm_reset_control_get_exclusive(dev, CTL_RESETS[i]); 222 if (IS_ERR(resets[i])) { 223 dev_err(dev, "%s reset not found\n", CTL_RESETS[i]); 224 return PTR_ERR(resets[i]); 225 } 226 } 227 228 for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) { 229 ta->resets[i] = devm_reset_control_get_exclusive(dev, PHY_RESETS[i]); 230 if (IS_ERR(ta->resets[i])) { 231 dev_err(dev, "%s reset not found\n", PHY_RESETS[i]); 232 return PTR_ERR(ta->resets[i]); 233 } 234 } 235 236 for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) 237 reset_control_assert(resets[i]); 238 239 for (i = 0; i < ARRAY_SIZE(PHY_RESETS); i++) 240 reset_control_assert(ta->resets[i]); 241 /* 242 * Out-of-band reset of the controller after PHY reset will cause 243 * controller malfunctioning, so we should use in-band controller 244 * reset only and leave the controller de-asserted here. 245 */ 246 for (i = 0; i < ARRAY_SIZE(CTL_RESETS); i++) 247 reset_control_deassert(resets[i]); 248 249 /* Need to wait at least 20us after de-assert the controller */ 250 usleep_range(20, 100); 251 252 return usb_add_phy_dev(phy); 253 } 254 255 static void phy_remove(struct platform_device *pdev) 256 { 257 struct tca_apb *ta = platform_get_drvdata(pdev); 258 259 usb_remove_phy(&ta->phy); 260 } 261 262 static const struct of_device_id intel_usb_phy_dt_ids[] = { 263 { .compatible = "intel,lgm-usb-phy" }, 264 { } 265 }; 266 MODULE_DEVICE_TABLE(of, intel_usb_phy_dt_ids); 267 268 static struct platform_driver lgm_phy_driver = { 269 .driver = { 270 .name = "lgm-usb-phy", 271 .of_match_table = intel_usb_phy_dt_ids, 272 }, 273 .probe = phy_probe, 274 .remove_new = phy_remove, 275 }; 276 277 module_platform_driver(lgm_phy_driver); 278 279 MODULE_DESCRIPTION("Intel LGM USB PHY driver"); 280 MODULE_AUTHOR("Li Yin <yin1.li@intel.com>"); 281 MODULE_AUTHOR("Vadivel Murugan R <vadivel.muruganx.ramuthevar@linux.intel.com>"); 282 MODULE_LICENSE("GPL v2"); 283