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1// SPDX-License-Identifier: GPL-2.0-only2 3#include <linux/module.h>4#include <linux/platform_device.h>5#include <linux/regmap.h>6 7#include <linux/slab.h>8#include <linux/of.h>9#include <linux/io.h>10#include <linux/usb/phy_companion.h>11#include <linux/clk.h>12#include <linux/err.h>13#include <linux/pm_runtime.h>14#include <linux/delay.h>15#include <linux/phy/phy.h>16 17#include <linux/mfd/syscon.h>18 19/*20 * TRM has two sets of USB_CTRL registers.. The correct register bits21 * are in TRM section 24.9.8.2 USB_CTRL Register. The TRM documents the22 * phy as being SR70LX Synopsys USB 2.0 OTG nanoPHY. It also seems at23 * least dm816x rev c ignores writes to USB_CTRL register, but the TI24 * kernel is writing to those so it's possible that later revisions25 * have worknig USB_CTRL register.26 *27 * Also note that At least USB_CTRL register seems to be dm816x specific28 * according to the TRM. It's possible that USBPHY_CTRL is more generic,29 * but that would have to be checked against the SR70LX documentation30 * which does not seem to be publicly available.31 *32 * Finally, the phy on dm814x and am335x is different from dm816x.33 */34#define DM816X_USB_CTRL_PHYCLKSRC BIT(8) /* 1 = PLL ref clock */35#define DM816X_USB_CTRL_PHYSLEEP1 BIT(1) /* Enable the first phy */36#define DM816X_USB_CTRL_PHYSLEEP0 BIT(0) /* Enable the second phy */37 38#define DM816X_USBPHY_CTRL_TXRISETUNE 139#define DM816X_USBPHY_CTRL_TXVREFTUNE 0xc40#define DM816X_USBPHY_CTRL_TXPREEMTUNE 0x241 42struct dm816x_usb_phy {43 struct regmap *syscon;44 struct device *dev;45 unsigned int instance;46 struct clk *refclk;47 struct usb_phy phy;48 unsigned int usb_ctrl; /* Shared between phy0 and phy1 */49 unsigned int usbphy_ctrl;50};51 52static int dm816x_usb_phy_set_host(struct usb_otg *otg, struct usb_bus *host)53{54 otg->host = host;55 if (!host)56 otg->state = OTG_STATE_UNDEFINED;57 58 return 0;59}60 61static int dm816x_usb_phy_set_peripheral(struct usb_otg *otg,62 struct usb_gadget *gadget)63{64 otg->gadget = gadget;65 if (!gadget)66 otg->state = OTG_STATE_UNDEFINED;67 68 return 0;69}70 71static int dm816x_usb_phy_init(struct phy *x)72{73 struct dm816x_usb_phy *phy = phy_get_drvdata(x);74 unsigned int val;75 76 if (clk_get_rate(phy->refclk) != 24000000)77 dev_warn(phy->dev, "nonstandard phy refclk\n");78 79 /* Set PLL ref clock and put phys to sleep */80 regmap_update_bits(phy->syscon, phy->usb_ctrl,81 DM816X_USB_CTRL_PHYCLKSRC |82 DM816X_USB_CTRL_PHYSLEEP1 |83 DM816X_USB_CTRL_PHYSLEEP0,84 0);85 regmap_read(phy->syscon, phy->usb_ctrl, &val);86 if ((val & 3) != 0)87 dev_info(phy->dev,88 "Working dm816x USB_CTRL! (0x%08x)\n",89 val);90 91 /*92 * TI kernel sets these values for "symmetrical eye diagram and93 * better signal quality" so let's assume somebody checked the94 * values with a scope and set them here too.95 */96 regmap_read(phy->syscon, phy->usbphy_ctrl, &val);97 val |= DM816X_USBPHY_CTRL_TXRISETUNE |98 DM816X_USBPHY_CTRL_TXVREFTUNE |99 DM816X_USBPHY_CTRL_TXPREEMTUNE;100 regmap_write(phy->syscon, phy->usbphy_ctrl, val);101 102 return 0;103}104 105static const struct phy_ops ops = {106 .init = dm816x_usb_phy_init,107 .owner = THIS_MODULE,108};109 110static int __maybe_unused dm816x_usb_phy_runtime_suspend(struct device *dev)111{112 struct dm816x_usb_phy *phy = dev_get_drvdata(dev);113 unsigned int mask, val;114 int error = 0;115 116 mask = BIT(phy->instance);117 val = ~BIT(phy->instance);118 error = regmap_update_bits(phy->syscon, phy->usb_ctrl,119 mask, val);120 if (error)121 dev_err(phy->dev, "phy%i failed to power off\n",122 phy->instance);123 clk_disable(phy->refclk);124 125 return 0;126}127 128static int __maybe_unused dm816x_usb_phy_runtime_resume(struct device *dev)129{130 struct dm816x_usb_phy *phy = dev_get_drvdata(dev);131 unsigned int mask, val;132 int error;133 134 error = clk_enable(phy->refclk);135 if (error)136 return error;137 138 /*139 * Note that at least dm816x rev c does not seem to do140 * anything with the USB_CTRL register. But let's follow141 * what the TI tree is doing in case later revisions use142 * USB_CTRL.143 */144 mask = BIT(phy->instance);145 val = BIT(phy->instance);146 error = regmap_update_bits(phy->syscon, phy->usb_ctrl,147 mask, val);148 if (error) {149 dev_err(phy->dev, "phy%i failed to power on\n",150 phy->instance);151 clk_disable(phy->refclk);152 return error;153 }154 155 return 0;156}157 158static UNIVERSAL_DEV_PM_OPS(dm816x_usb_phy_pm_ops,159 dm816x_usb_phy_runtime_suspend,160 dm816x_usb_phy_runtime_resume,161 NULL);162 163static const struct of_device_id dm816x_usb_phy_id_table[] = {164 {165 .compatible = "ti,dm8168-usb-phy",166 },167 {},168};169MODULE_DEVICE_TABLE(of, dm816x_usb_phy_id_table);170 171static int dm816x_usb_phy_probe(struct platform_device *pdev)172{173 struct dm816x_usb_phy *phy;174 struct resource *res;175 struct phy *generic_phy;176 struct phy_provider *phy_provider;177 struct usb_otg *otg;178 int error;179 180 phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);181 if (!phy)182 return -ENOMEM;183 184 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);185 if (!res)186 return -ENOENT;187 188 phy->syscon = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,189 "syscon");190 if (IS_ERR(phy->syscon))191 return PTR_ERR(phy->syscon);192 193 /*194 * According to sprs614e.pdf, the first usb_ctrl is shared and195 * the second instance for usb_ctrl is reserved.. Also the196 * register bits are different from earlier TRMs.197 */198 phy->usb_ctrl = 0x20;199 phy->usbphy_ctrl = (res->start & 0xff) + 4;200 if (phy->usbphy_ctrl == 0x2c)201 phy->instance = 1;202 203 otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);204 if (!otg)205 return -ENOMEM;206 207 phy->dev = &pdev->dev;208 phy->phy.dev = phy->dev;209 phy->phy.label = "dm8168_usb_phy";210 phy->phy.otg = otg;211 phy->phy.type = USB_PHY_TYPE_USB2;212 otg->set_host = dm816x_usb_phy_set_host;213 otg->set_peripheral = dm816x_usb_phy_set_peripheral;214 otg->usb_phy = &phy->phy;215 216 platform_set_drvdata(pdev, phy);217 218 phy->refclk = devm_clk_get(phy->dev, "refclk");219 if (IS_ERR(phy->refclk))220 return PTR_ERR(phy->refclk);221 error = clk_prepare(phy->refclk);222 if (error)223 return error;224 225 pm_runtime_enable(phy->dev);226 generic_phy = devm_phy_create(phy->dev, NULL, &ops);227 if (IS_ERR(generic_phy)) {228 error = PTR_ERR(generic_phy);229 goto clk_unprepare;230 }231 232 phy_set_drvdata(generic_phy, phy);233 234 phy_provider = devm_of_phy_provider_register(phy->dev,235 of_phy_simple_xlate);236 if (IS_ERR(phy_provider)) {237 error = PTR_ERR(phy_provider);238 goto clk_unprepare;239 }240 241 usb_add_phy_dev(&phy->phy);242 243 return 0;244 245clk_unprepare:246 pm_runtime_disable(phy->dev);247 clk_unprepare(phy->refclk);248 return error;249}250 251static void dm816x_usb_phy_remove(struct platform_device *pdev)252{253 struct dm816x_usb_phy *phy = platform_get_drvdata(pdev);254 255 usb_remove_phy(&phy->phy);256 pm_runtime_disable(phy->dev);257 clk_unprepare(phy->refclk);258}259 260static struct platform_driver dm816x_usb_phy_driver = {261 .probe = dm816x_usb_phy_probe,262 .remove_new = dm816x_usb_phy_remove,263 .driver = {264 .name = "dm816x-usb-phy",265 .pm = &dm816x_usb_phy_pm_ops,266 .of_match_table = dm816x_usb_phy_id_table,267 },268};269 270module_platform_driver(dm816x_usb_phy_driver);271 272MODULE_ALIAS("platform:dm816x_usb");273MODULE_AUTHOR("Tony Lindgren <tony@atomide.com>");274MODULE_DESCRIPTION("dm816x usb phy driver");275MODULE_LICENSE("GPL v2");276