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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Broadcom Northstar USB 2.0 PHY Driver4 *5 * Copyright (C) 2016 Rafał Miłecki <zajec5@gmail.com>6 */7 8#include <linux/bcma/bcma.h>9#include <linux/clk.h>10#include <linux/delay.h>11#include <linux/err.h>12#include <linux/mfd/syscon.h>13#include <linux/module.h>14#include <linux/of_address.h>15#include <linux/of_platform.h>16#include <linux/phy/phy.h>17#include <linux/platform_device.h>18#include <linux/regmap.h>19#include <linux/slab.h>20 21struct bcm_ns_usb2 {22 struct device *dev;23 struct clk *ref_clk;24 struct phy *phy;25 struct regmap *clkset;26 void __iomem *base;27 28 /* Deprecated binding */29 void __iomem *dmu;30};31 32static int bcm_ns_usb2_phy_init(struct phy *phy)33{34 struct bcm_ns_usb2 *usb2 = phy_get_drvdata(phy);35 struct device *dev = usb2->dev;36 u32 ref_clk_rate, usb2ctl, usb_pll_ndiv, usb_pll_pdiv;37 int err = 0;38 39 err = clk_prepare_enable(usb2->ref_clk);40 if (err < 0) {41 dev_err(dev, "Failed to prepare ref clock: %d\n", err);42 goto err_out;43 }44 45 ref_clk_rate = clk_get_rate(usb2->ref_clk);46 if (!ref_clk_rate) {47 dev_err(dev, "Failed to get ref clock rate\n");48 err = -EINVAL;49 goto err_clk_off;50 }51 52 if (usb2->base)53 usb2ctl = readl(usb2->base);54 else55 usb2ctl = readl(usb2->dmu + BCMA_DMU_CRU_USB2_CONTROL);56 57 if (usb2ctl & BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK) {58 usb_pll_pdiv = usb2ctl;59 usb_pll_pdiv &= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_MASK;60 usb_pll_pdiv >>= BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_PDIV_SHIFT;61 } else {62 usb_pll_pdiv = 1 << 3;63 }64 65 /* Calculate ndiv based on a solid 1920 MHz that is for USB2 PHY */66 usb_pll_ndiv = (1920000000 * usb_pll_pdiv) / ref_clk_rate;67 68 /* Unlock DMU PLL settings with some magic value */69 if (usb2->clkset)70 regmap_write(usb2->clkset, 0, 0x0000ea68);71 else72 writel(0x0000ea68, usb2->dmu + BCMA_DMU_CRU_CLKSET_KEY);73 74 /* Write USB 2.0 PLL control setting */75 usb2ctl &= ~BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_MASK;76 usb2ctl |= usb_pll_ndiv << BCMA_DMU_CRU_USB2_CONTROL_USB_PLL_NDIV_SHIFT;77 if (usb2->base)78 writel(usb2ctl, usb2->base);79 else80 writel(usb2ctl, usb2->dmu + BCMA_DMU_CRU_USB2_CONTROL);81 82 /* Lock DMU PLL settings */83 if (usb2->clkset)84 regmap_write(usb2->clkset, 0, 0x00000000);85 else86 writel(0x00000000, usb2->dmu + BCMA_DMU_CRU_CLKSET_KEY);87 88err_clk_off:89 clk_disable_unprepare(usb2->ref_clk);90err_out:91 return err;92}93 94static const struct phy_ops ops = {95 .init = bcm_ns_usb2_phy_init,96 .owner = THIS_MODULE,97};98 99static int bcm_ns_usb2_probe(struct platform_device *pdev)100{101 struct device *dev = &pdev->dev;102 struct bcm_ns_usb2 *usb2;103 struct phy_provider *phy_provider;104 105 usb2 = devm_kzalloc(&pdev->dev, sizeof(*usb2), GFP_KERNEL);106 if (!usb2)107 return -ENOMEM;108 usb2->dev = dev;109 110 if (of_property_present(dev->of_node, "brcm,syscon-clkset")) {111 usb2->base = devm_platform_ioremap_resource(pdev, 0);112 if (IS_ERR(usb2->base)) {113 dev_err(dev, "Failed to map control reg\n");114 return PTR_ERR(usb2->base);115 }116 117 usb2->clkset = syscon_regmap_lookup_by_phandle(dev->of_node,118 "brcm,syscon-clkset");119 if (IS_ERR(usb2->clkset)) {120 dev_err(dev, "Failed to lookup clkset regmap\n");121 return PTR_ERR(usb2->clkset);122 }123 } else {124 usb2->dmu = devm_platform_ioremap_resource_byname(pdev, "dmu");125 if (IS_ERR(usb2->dmu)) {126 dev_err(dev, "Failed to map DMU regs\n");127 return PTR_ERR(usb2->dmu);128 }129 130 dev_warn(dev, "using deprecated DT binding\n");131 }132 133 usb2->ref_clk = devm_clk_get(dev, "phy-ref-clk");134 if (IS_ERR(usb2->ref_clk)) {135 dev_err_probe(dev, PTR_ERR(usb2->ref_clk), "failed to get ref clk\n");136 return PTR_ERR(usb2->ref_clk);137 }138 139 usb2->phy = devm_phy_create(dev, NULL, &ops);140 if (IS_ERR(usb2->phy))141 return PTR_ERR(usb2->phy);142 143 phy_set_drvdata(usb2->phy, usb2);144 platform_set_drvdata(pdev, usb2);145 146 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);147 return PTR_ERR_OR_ZERO(phy_provider);148}149 150static const struct of_device_id bcm_ns_usb2_id_table[] = {151 { .compatible = "brcm,ns-usb2-phy", },152 {},153};154MODULE_DEVICE_TABLE(of, bcm_ns_usb2_id_table);155 156static struct platform_driver bcm_ns_usb2_driver = {157 .probe = bcm_ns_usb2_probe,158 .driver = {159 .name = "bcm_ns_usb2",160 .of_match_table = bcm_ns_usb2_id_table,161 },162};163module_platform_driver(bcm_ns_usb2_driver);164 165MODULE_DESCRIPTION("Broadcom Northstar USB 2.0 PHY Driver");166MODULE_LICENSE("GPL v2");167