diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/phy/renesas/phy-rcar-gen3-pcie.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/phy/renesas/phy-rcar-gen3-pcie.c b/drivers/phy/renesas/phy-rcar-gen3-pcie.c new file mode 100644 index 000000000..4dc721eb9 --- /dev/null +++ b/drivers/phy/renesas/phy-rcar-gen3-pcie.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Renesas R-Car Gen3 PCIe PHY driver + * + * Copyright (C) 2018 Cogent Embedded, Inc. + */ + +#include <linux/clk.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/phy/phy.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> + +#define PHY_CTRL 0x4000 /* R8A77980 only */ + +/* PHY control register (PHY_CTRL) */ +#define PHY_CTRL_PHY_PWDN BIT(2) + +struct rcar_gen3_phy { + struct phy *phy; + spinlock_t lock; + void __iomem *base; +}; + +static void rcar_gen3_phy_pcie_modify_reg(struct phy *p, unsigned int reg, + u32 clear, u32 set) +{ + struct rcar_gen3_phy *phy = phy_get_drvdata(p); + void __iomem *base = phy->base; + unsigned long flags; + u32 value; + + spin_lock_irqsave(&phy->lock, flags); + + value = readl(base + reg); + value &= ~clear; + value |= set; + writel(value, base + reg); + + spin_unlock_irqrestore(&phy->lock, flags); +} + +static int r8a77980_phy_pcie_power_on(struct phy *p) +{ + /* Power on the PCIe PHY */ + rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, PHY_CTRL_PHY_PWDN, 0); + + return 0; +} + +static int r8a77980_phy_pcie_power_off(struct phy *p) +{ + /* Power off the PCIe PHY */ + rcar_gen3_phy_pcie_modify_reg(p, PHY_CTRL, 0, PHY_CTRL_PHY_PWDN); + + return 0; +} + +static const struct phy_ops r8a77980_phy_pcie_ops = { + .power_on = r8a77980_phy_pcie_power_on, + .power_off = r8a77980_phy_pcie_power_off, + .owner = THIS_MODULE, +}; + +static const struct of_device_id rcar_gen3_phy_pcie_match_table[] = { + { .compatible = "renesas,r8a77980-pcie-phy" }, + { } +}; +MODULE_DEVICE_TABLE(of, rcar_gen3_phy_pcie_match_table); + +static int rcar_gen3_phy_pcie_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct phy_provider *provider; + struct rcar_gen3_phy *phy; + void __iomem *base; + int error; + + if (!dev->of_node) { + dev_err(dev, + "This driver must only be instantiated from the device tree\n"); + return -EINVAL; + } + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return PTR_ERR(base); + + phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL); + if (!phy) + return -ENOMEM; + + spin_lock_init(&phy->lock); + + phy->base = base; + + /* + * devm_phy_create() will call pm_runtime_enable(&phy->dev); + * And then, phy-core will manage runtime PM for this device. + */ + pm_runtime_enable(dev); + + phy->phy = devm_phy_create(dev, NULL, &r8a77980_phy_pcie_ops); + if (IS_ERR(phy->phy)) { + dev_err(dev, "Failed to create PCIe PHY\n"); + error = PTR_ERR(phy->phy); + goto error; + } + phy_set_drvdata(phy->phy, phy); + + provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); + if (IS_ERR(provider)) { + dev_err(dev, "Failed to register PHY provider\n"); + error = PTR_ERR(provider); + goto error; + } + + return 0; + +error: + pm_runtime_disable(dev); + + return error; +} + +static int rcar_gen3_phy_pcie_remove(struct platform_device *pdev) +{ + pm_runtime_disable(&pdev->dev); + + return 0; +}; + +static struct platform_driver rcar_gen3_phy_driver = { + .driver = { + .name = "phy_rcar_gen3_pcie", + .of_match_table = rcar_gen3_phy_pcie_match_table, + }, + .probe = rcar_gen3_phy_pcie_probe, + .remove = rcar_gen3_phy_pcie_remove, +}; + +module_platform_driver(rcar_gen3_phy_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Renesas R-Car Gen3 PCIe PHY"); +MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>"); |