147 lines · c
1// SPDX-License-Identifier: GPL-2.02/*3 * Renesas R-Car Gen3 PCIe PHY driver4 *5 * Copyright (C) 2018 Cogent Embedded, Inc.6 */7 8#include <linux/clk.h>9#include <linux/io.h>10#include <linux/module.h>11#include <linux/of.h>12#include <linux/phy/phy.h>13#include <linux/platform_device.h>14#include <linux/spinlock.h>15 16#define PHY_CTRL 0x4000 /* R8A77980 only */17 18/* PHY control register (PHY_CTRL) */19#define PHY_CTRL_PHY_PWDN BIT(2)20 21struct rcar_gen3_phy {22 struct phy *phy;23 spinlock_t lock;24 void __iomem *base;25};26 27static void rcar_gen3_phy_pcie_modify_reg(struct phy *p, unsigned int reg,28 u32 clear, u32 set)29{30 struct rcar_gen3_phy *phy = phy_get_drvdata(p);31 void __iomem *base = phy->base;32 unsigned long flags;33 u32 value;34 35 spin_lock_irqsave(&phy->lock, flags);36 37 value = readl(base + reg);38 value &= ~clear;39 value |= set;40 writel(value, base + reg);41 42 spin_unlock_irqrestore(&phy->lock, flags);43}44 45static int r8a77980_phy_pcie_power_on(struct phy *p)46{47 /* Power on the PCIe PHY */48 rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, PHY_CTRL_PHY_PWDN, 0);49 50 return 0;51}52 53static int r8a77980_phy_pcie_power_off(struct phy *p)54{55 /* Power off the PCIe PHY */56 rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, 0, PHY_CTRL_PHY_PWDN);57 58 return 0;59}60 61static const struct phy_ops r8a77980_phy_pcie_ops = {62 .power_on = r8a77980_phy_pcie_power_on,63 .power_off = r8a77980_phy_pcie_power_off,64 .owner = THIS_MODULE,65};66 67static const struct of_device_id rcar_gen3_phy_pcie_match_table[] = {68 { .compatible = "renesas,r8a77980-pcie-phy" },69 { }70};71MODULE_DEVICE_TABLE(of, rcar_gen3_phy_pcie_match_table);72 73static int rcar_gen3_phy_pcie_probe(struct platform_device *pdev)74{75 struct device *dev = &pdev->dev;76 struct phy_provider *provider;77 struct rcar_gen3_phy *phy;78 void __iomem *base;79 int error;80 81 if (!dev->of_node) {82 dev_err(dev,83 "This driver must only be instantiated from the device tree\n");84 return -EINVAL;85 }86 87 base = devm_platform_ioremap_resource(pdev, 0);88 if (IS_ERR(base))89 return PTR_ERR(base);90 91 phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);92 if (!phy)93 return -ENOMEM;94 95 spin_lock_init(&phy->lock);96 97 phy->base = base;98 99 /*100 * devm_phy_create() will call pm_runtime_enable(&phy->dev);101 * And then, phy-core will manage runtime PM for this device.102 */103 pm_runtime_enable(dev);104 105 phy->phy = devm_phy_create(dev, NULL, &r8a77980_phy_pcie_ops);106 if (IS_ERR(phy->phy)) {107 dev_err(dev, "Failed to create PCIe PHY\n");108 error = PTR_ERR(phy->phy);109 goto error;110 }111 phy_set_drvdata(phy->phy, phy);112 113 provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);114 if (IS_ERR(provider)) {115 dev_err(dev, "Failed to register PHY provider\n");116 error = PTR_ERR(provider);117 goto error;118 }119 120 return 0;121 122error:123 pm_runtime_disable(dev);124 125 return error;126}127 128static void rcar_gen3_phy_pcie_remove(struct platform_device *pdev)129{130 pm_runtime_disable(&pdev->dev);131};132 133static struct platform_driver rcar_gen3_phy_driver = {134 .driver = {135 .name = "phy_rcar_gen3_pcie",136 .of_match_table = rcar_gen3_phy_pcie_match_table,137 },138 .probe = rcar_gen3_phy_pcie_probe,139 .remove_new = rcar_gen3_phy_pcie_remove,140};141 142module_platform_driver(rcar_gen3_phy_driver);143 144MODULE_LICENSE("GPL v2");145MODULE_DESCRIPTION("Renesas R-Car Gen3 PCIe PHY");146MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");147