On Mon, Apr 17, 2017 at 9:29 PM, Hauke Mehrtens <hauke@xxxxxxxxxx> wrote: > From: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > > This driver starts the DWC2 core(s) built into the XWAY SoCs and provides > the PHY interfaces for each core. The phy instances can be passed to the > dwc2 driver, which already supports the generic phy interface. > > Signed-off-by: Hauke Mehrtens <hauke@xxxxxxxxxx> > --- > .../bindings/phy/phy-lantiq-rcu-usb2.txt | 59 ++++ > arch/mips/lantiq/xway/reset.c | 43 --- > arch/mips/lantiq/xway/sysctrl.c | 24 +- > drivers/phy/Kconfig | 8 + > drivers/phy/Makefile | 1 + > drivers/phy/phy-lantiq-rcu-usb2.c | 325 +++++++++++++++++++++ > 6 files changed, 405 insertions(+), 55 deletions(-) > create mode 100644 Documentation/devicetree/bindings/phy/phy-lantiq-rcu-usb2.txt > create mode 100644 drivers/phy/phy-lantiq-rcu-usb2.c > > diff --git a/Documentation/devicetree/bindings/phy/phy-lantiq-rcu-usb2.txt b/Documentation/devicetree/bindings/phy/phy-lantiq-rcu-usb2.txt > new file mode 100644 > index 000000000000..0ec9f790b6e0 > --- /dev/null > +++ b/Documentation/devicetree/bindings/phy/phy-lantiq-rcu-usb2.txt > @@ -0,0 +1,59 @@ > +Lantiq XWAY SoC RCU USB 1.1/2.0 PHY binding > +=========================================== > + > +This binding describes the USB PHY hardware provided by the RCU module on the > +Lantiq XWAY SoCs. > + > + > +------------------------------------------------------------------------------- > +Required properties (controller (parent) node): > +- compatible : Should be one of > + "lantiq,ase-rcu-usb2-phy" > + "lantiq,danube-rcu-usb2-phy" > + "lantiq,xrx100-rcu-usb2-phy" > + "lantiq,xrx200-rcu-usb2-phy" > + "lantiq,xrx300-rcu-usb2-phy" > +- lantiq,rcu-syscon : A phandle to the RCU module and the offsets to the > + USB PHY configuration and USB MAC registers. > +- address-cells : should be 1 > +- size-cells : should be 0 > +- phy-cells : from the generic PHY bindings, must be 1 > + > +Optional properties (controller (parent) node): > +- vbus-gpio : References a GPIO which enables VBUS all given USB > + ports. > + > +Required nodes : A sub-node is required for each USB PHY port. > + > + > +------------------------------------------------------------------------------- > +Required properties (port (child) node): > +- reg : The ID of the USB port, usually 0 or 1. > +- clocks : References to the (PMU) "ctrl" and "phy" clk gates. > +- clock-names : Must be one of the following: > + "ctrl" > + "phy" > +- resets : References to the RCU USB configuration reset bits. > +- reset-names : Must be one of the following: > + "analog-config" (optional) > + "statemachine-soft" (optional) > + > +Optional properties (port (child) node): > +- vbus-gpio : References a GPIO which enables VBUS for the USB port. > + > + > +------------------------------------------------------------------------------- > +Example for the USB PHYs on an xRX200 SoC: > + usb_phys0: rcu-usb2-phy@0 { > + compatible = "lantiq,xrx200-rcu-usb2-phy"; > + reg = <0>; > + > + lantiq,rcu-syscon = <&rcu0 0x18 0x38>; > + clocks = <&pmu PMU_GATE_USB0_CTRL>, > + <&pmu PMU_GATE_USB0_PHY>; > + clock-names = "ctrl", "phy"; > + vbus-gpios = <&gpio 32 GPIO_ACTIVE_HIGH>; > + resets = <&rcu_reset1 4>, <&rcu_reset0 4>; > + reset-names = "phy", "ctrl"; > + #phy-cells = <0>; > + }; > diff --git a/arch/mips/lantiq/xway/reset.c b/arch/mips/lantiq/xway/reset.c > index 3f30fb81a50f..5aec1f54275b 100644 > --- a/arch/mips/lantiq/xway/reset.c > +++ b/arch/mips/lantiq/xway/reset.c > @@ -124,45 +124,6 @@ static void ltq_machine_power_off(void) > unreachable(); > } > > -static void ltq_usb_init(void) > -{ > - /* Power for USB cores 1 & 2 */ > - ltq_pmu_enable(PMU_AHBM); > - ltq_pmu_enable(PMU_USB0); > - ltq_pmu_enable(PMU_USB1); > - > - ltq_rcu_w32(ltq_rcu_r32(RCU_CFG1A) | BIT(0), RCU_CFG1A); > - ltq_rcu_w32(ltq_rcu_r32(RCU_CFG1B) | BIT(0), RCU_CFG1B); > - > - /* Enable USB PHY power for cores 1 & 2 */ > - ltq_pmu_enable(PMU_USB0_P); > - ltq_pmu_enable(PMU_USB1_P); > - > - /* Configure cores to host mode */ > - ltq_rcu_w32(ltq_rcu_r32(RCU_USB1CFG) & ~RCU_USBCFG_HDSEL_BIT, > - RCU_USB1CFG); > - ltq_rcu_w32(ltq_rcu_r32(RCU_USB2CFG) & ~RCU_USBCFG_HDSEL_BIT, > - RCU_USB2CFG); > - > - /* Select DMA endianness (Host-endian: big-endian) */ > - ltq_rcu_w32((ltq_rcu_r32(RCU_USB1CFG) & ~RCU_USBCFG_SLV_END_BIT) > - | RCU_USBCFG_HOST_END_BIT, RCU_USB1CFG); > - ltq_rcu_w32(ltq_rcu_r32((RCU_USB2CFG) & ~RCU_USBCFG_SLV_END_BIT) > - | RCU_USBCFG_HOST_END_BIT, RCU_USB2CFG); > - > - /* Hard reset USB state machines */ > - ltq_rcu_w32(ltq_rcu_r32(RCU_USBRESET) | USBRESET_BIT, RCU_USBRESET); > - udelay(50 * 1000); > - ltq_rcu_w32(ltq_rcu_r32(RCU_USBRESET) & ~USBRESET_BIT, RCU_USBRESET); > - > - /* Soft reset USB state machines */ > - ltq_rcu_w32(ltq_rcu_r32(RCU_USBRESET2) > - | USB1RESET_BIT | USB2RESET_BIT, RCU_USBRESET2); > - udelay(50 * 1000); > - ltq_rcu_w32(ltq_rcu_r32(RCU_USBRESET2) > - & ~(USB1RESET_BIT | USB2RESET_BIT), RCU_USBRESET2); > -} > - > static int __init mips_reboot_setup(void) > { > struct resource res; > @@ -186,10 +147,6 @@ static int __init mips_reboot_setup(void) > if (!ltq_rcu_membase) > panic("Failed to remap core memory"); > > - if (of_machine_is_compatible("lantiq,ar9") || > - of_machine_is_compatible("lantiq,vr9")) > - ltq_usb_init(); > - > _machine_restart = ltq_machine_restart; > _machine_halt = ltq_machine_halt; > pm_power_off = ltq_machine_power_off; > diff --git a/arch/mips/lantiq/xway/sysctrl.c b/arch/mips/lantiq/xway/sysctrl.c > index 5764d3ddce69..18725f2d5b67 100644 > --- a/arch/mips/lantiq/xway/sysctrl.c > +++ b/arch/mips/lantiq/xway/sysctrl.c > @@ -469,8 +469,8 @@ void __init ltq_soc_init(void) > > if (of_machine_is_compatible("lantiq,grx390") || > of_machine_is_compatible("lantiq,ar10")) { > - clkdev_add_pmu("1e101000.usb", "phy", 1, 2, PMU_ANALOG_USB0_P); > - clkdev_add_pmu("1e106000.usb", "phy", 1, 2, PMU_ANALOG_USB1_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "phy", 1, 2, PMU_ANALOG_USB0_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@1", "phy", 1, 2, PMU_ANALOG_USB1_P); > /* rc 0 */ > clkdev_add_pmu("1d900000.pcie", "phy", 1, 2, PMU_ANALOG_PCIE0_P); > clkdev_add_pmu("1d900000.pcie", "msi", 1, 1, PMU1_PCIE_MSI); > @@ -490,8 +490,8 @@ void __init ltq_soc_init(void) > else > clkdev_add_static(CLOCK_133M, CLOCK_133M, > CLOCK_133M, CLOCK_133M); > - clkdev_add_pmu("1e101000.usb", "ctl", 1, 0, PMU_USB0); > - clkdev_add_pmu("1e101000.usb", "phy", 1, 0, PMU_USB0_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "ctrl", 1, 0, PMU_USB0); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "phy", 1, 0, PMU_USB0_P); > clkdev_add_pmu("1e180000.etop", "ppe", 1, 0, PMU_PPE); > clkdev_add_cgu("1e180000.etop", "ephycgu", CGU_EPHY); > clkdev_add_pmu("1e180000.etop", "ephy", 1, 0, PMU_EPHY); > @@ -525,10 +525,10 @@ void __init ltq_soc_init(void) > } else if (of_machine_is_compatible("lantiq,vr9")) { > clkdev_add_static(ltq_vr9_cpu_hz(), ltq_vr9_fpi_hz(), > ltq_vr9_fpi_hz(), ltq_vr9_pp32_hz()); > - clkdev_add_pmu("1e101000.usb", "phy", 1, 0, PMU_USB0_P); > - clkdev_add_pmu("1e101000.usb", "ctl", 1, 0, PMU_USB0 | PMU_AHBM); > - clkdev_add_pmu("1e106000.usb", "phy", 1, 0, PMU_USB1_P); > - clkdev_add_pmu("1e106000.usb", "ctl", 1, 0, PMU_USB1 | PMU_AHBM); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "phy", 1, 0, PMU_USB0_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "ctrl", 1, 0, PMU_USB0 | PMU_AHBM); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@1", "phy", 1, 0, PMU_USB1_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@1", "ctrl", 1, 0, PMU_USB1 | PMU_AHBM); > clkdev_add_pmu("1d900000.pcie", "phy", 1, 1, PMU1_PCIE_PHY); > clkdev_add_pmu("1d900000.pcie", "bus", 1, 0, PMU_PCIE_CLK); > clkdev_add_pmu("1d900000.pcie", "msi", 1, 1, PMU1_PCIE_MSI); > @@ -548,8 +548,8 @@ void __init ltq_soc_init(void) > } else if (of_machine_is_compatible("lantiq,ar9")) { > clkdev_add_static(ltq_ar9_cpu_hz(), ltq_ar9_fpi_hz(), > ltq_ar9_fpi_hz(), CLOCK_250M); > - clkdev_add_pmu("1e101000.usb", "ctl", 1, 0, PMU_USB0); > - clkdev_add_pmu("1e101000.usb", "phy", 1, 0, PMU_USB0_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "ctrl", 1, 0, PMU_USB0); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "phy", 1, 0, PMU_USB0_P); > clkdev_add_pmu("1e106000.usb", "ctl", 1, 0, PMU_USB1); > clkdev_add_pmu("1e106000.usb", "phy", 1, 0, PMU_USB1_P); > clkdev_add_pmu("1e180000.etop", "switch", 1, 0, PMU_SWITCH); > @@ -560,8 +560,8 @@ void __init ltq_soc_init(void) > } else { > clkdev_add_static(ltq_danube_cpu_hz(), ltq_danube_fpi_hz(), > ltq_danube_fpi_hz(), ltq_danube_pp32_hz()); > - clkdev_add_pmu("1e101000.usb", "ctl", 1, 0, PMU_USB0); > - clkdev_add_pmu("1e101000.usb", "phy", 1, 0, PMU_USB0_P); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "ctrl", 1, 0, PMU_USB0); > + clkdev_add_pmu("1f203000.rcu:rcu-usb2-phy@0", "phy", 1, 0, PMU_USB0_P); > clkdev_add_pmu("1e103000.sdio", NULL, 1, 0, PMU_SDIO); > clkdev_add_pmu("1e103100.deu", NULL, 1, 0, PMU_DEU); > clkdev_add_pmu("1e116000.mei", "dfe", 1, 0, PMU_DFE); > diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig > index 005cadb7a3f8..dbb450e3ba04 100644 > --- a/drivers/phy/Kconfig > +++ b/drivers/phy/Kconfig > @@ -488,6 +488,14 @@ config PHY_CYGNUS_PCIE > Enable this to support the Broadcom Cygnus PCIe PHY. > If unsure, say N. > > +config PHY_LANTIQ_RCU_USB2 > + tristate "Lantiq XWAY SoC RCU based USB PHY" > + depends on SOC_TYPE_XWAY > + depends on OF > + select GENERIC_PHY > + help > + Support for the USB PHY(s) on the Lantiq XWAY family SoCs. > + > source "drivers/phy/tegra/Kconfig" > > config PHY_NS2_PCIE > diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile > index dd8f3b5d2918..52631f5ac470 100644 > --- a/drivers/phy/Makefile > +++ b/drivers/phy/Makefile > @@ -59,6 +59,7 @@ obj-$(CONFIG_PHY_TUSB1210) += phy-tusb1210.o > obj-$(CONFIG_PHY_BRCM_SATA) += phy-brcm-sata.o > obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o > obj-$(CONFIG_PHY_CYGNUS_PCIE) += phy-bcm-cygnus-pcie.o > +obj-$(CONFIG_PHY_LANTIQ_RCU_USB2) += phy-lantiq-rcu-usb2.o > obj-$(CONFIG_ARCH_TEGRA) += tegra/ > obj-$(CONFIG_PHY_NS2_PCIE) += phy-bcm-ns2-pcie.o > obj-$(CONFIG_PHY_MESON8B_USB2) += phy-meson8b-usb2.o > diff --git a/drivers/phy/phy-lantiq-rcu-usb2.c b/drivers/phy/phy-lantiq-rcu-usb2.c > new file mode 100644 > index 000000000000..9bff42afd256 > --- /dev/null > +++ b/drivers/phy/phy-lantiq-rcu-usb2.c > @@ -0,0 +1,325 @@ > +/* > + * Lantiq XWAY SoC RCU module based USB 1.1/2.0 PHY driver > + * > + * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> > + * Copyright (C) 2017 Hauke Mehrtens <hauke@xxxxxxxxxx> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#include <linux/clk.h> > +#include <linux/delay.h> > +#include <linux/gpio.h> > +#include <linux/gpio/consumer.h> > +#include <linux/mfd/syscon.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/of_gpio.h> > +#include <linux/phy/phy.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > +#include <linux/reset.h> > + > +#define MAX_VBUS_GPIO 2 > + > +/* Transmitter HS Pre-Emphasis Enable */ > +#define RCU_CFG1_TX_PEE BIT(0) > +/* Disconnect Threshold */ > +#define RCU_CFG1_DIS_THR_MASK 0x00038000 > +#define RCU_CFG1_DIS_THR_SHIFT 15 > + > +struct ltq_rcu_usb2_bits { > + u8 hostmode; > + u8 slave_endianness; > + u8 host_endianness; > + bool have_ana_cfg; > +}; > + > +struct ltq_rcu_usb2_priv { > + struct regmap *regmap; > + u32 phy_reg_offset; > + u32 ana_cfg1_reg_offset; > + const struct ltq_rcu_usb2_bits *reg_bits; > + struct device *dev; > + struct gpio_desc *gpiod_vbus[MAX_VBUS_GPIO]; > + struct phy *phy; > + struct clk *ctrl_gate_clk; > + struct clk *phy_gate_clk; > + struct reset_control *ctrl_reset; > + struct reset_control *phy_reset; > +}; > + > +static const struct ltq_rcu_usb2_bits xway_rcu_usb2_reg_bits = { > + .hostmode = 11, > + .slave_endianness = 9, > + .host_endianness = 10, > + .have_ana_cfg = false, > +}; > + > +static const struct ltq_rcu_usb2_bits xrx100_rcu_usb2_reg_bits = { > + .hostmode = 11, > + .slave_endianness = 17, > + .host_endianness = 10, > + .have_ana_cfg = false, > +}; > + > +static const struct ltq_rcu_usb2_bits xrx200_rcu_usb2_reg_bits = { > + .hostmode = 11, > + .slave_endianness = 9, > + .host_endianness = 10, > + .have_ana_cfg = true, > +}; > + > +static const struct of_device_id ltq_rcu_usb2_phy_of_match[] = { > + { > + .compatible = "lantiq,ase-rcu-usb2-phy", > + .data = &xway_rcu_usb2_reg_bits, > + }, > + { > + .compatible = "lantiq,danube-rcu-usb2-phy", > + .data = &xway_rcu_usb2_reg_bits, > + }, > + { > + .compatible = "lantiq,xrx100-rcu-usb2-phy", > + .data = &xrx100_rcu_usb2_reg_bits, > + }, > + { > + .compatible = "lantiq,xrx200-rcu-usb2-phy", > + .data = &xrx200_rcu_usb2_reg_bits, > + }, > + { > + .compatible = "lantiq,xrx300-rcu-usb2-phy", > + .data = &xrx200_rcu_usb2_reg_bits, > + }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, ltq_rcu_usb2_phy_of_match); > + > +static void ltq_rcu_usb2_set_vbus_gpio_value(struct gpio_desc **gpiods, > + int value) > +{ > + int i; > + > + for (i = 0; i < MAX_VBUS_GPIO; i++) > + if (!IS_ERR_OR_NULL(gpiods[i])) > + gpiod_set_value(gpiods[i], value); > +} > + > +static int ltq_rcu_usb2_phy_power_on(struct phy *phy) > +{ > + struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy); > + > + if (priv->phy_reset) > + reset_control_deassert(priv->phy_reset); > + > + /* enable the port-specific VBUS GPIOs if available */ > + ltq_rcu_usb2_set_vbus_gpio_value(priv->gpiod_vbus, 1); as I mentioned in my previous mail, if you pass a fixed regulator then the PHY framework handles this, see [1] (regulator_enable is called right before .phy_power_on and regulator_disable is called right after .phy_power_off) > + return 0; > +} > + > +static int ltq_rcu_usb2_phy_power_off(struct phy *phy) > +{ > + struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy); > + > + /* > + * only disable the port-specific VBUS GPIO here (if available), the > + * shared VBUS GPIO might still be used by another port > + */ > + ltq_rcu_usb2_set_vbus_gpio_value(priv->gpiod_vbus, 0); > + > + if (priv->phy_reset) > + reset_control_assert(priv->phy_reset); > + > + return 0; > +} > + > +static struct phy_ops ltq_rcu_usb2_phy_ops = { > + .power_on = ltq_rcu_usb2_phy_power_on, > + .power_off = ltq_rcu_usb2_phy_power_off, > + .owner = THIS_MODULE, > +}; > + > +static void ltq_rcu_usb2_start_cores(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct ltq_rcu_usb2_priv *priv = dev_get_drvdata(dev); > + > + /* Power on the USB core. */ > + if (clk_prepare_enable(priv->ctrl_gate_clk)) { > + dev_err(dev, "failed to enable CTRL gate\n"); > + return; > + } > + > + /* > + * Power on the USB PHY. We have to do it early because > + * otherwise the second core won't turn on properly. > + */ > + if (clk_prepare_enable(priv->phy_gate_clk)) { > + dev_err(dev, "failed to enable PHY gate\n"); > + return; > + } > + > + if (priv->reg_bits->have_ana_cfg) { > + regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset, > + RCU_CFG1_TX_PEE, RCU_CFG1_TX_PEE); > + regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset, > + RCU_CFG1_DIS_THR_MASK, 7 << RCU_CFG1_DIS_THR_SHIFT); > + } > + > + /* Configure core to host mode */ > + regmap_update_bits(priv->regmap, priv->phy_reg_offset, > + BIT(priv->reg_bits->hostmode), 0); > + > + /* Select DMA endianness (Host-endian: big-endian) */ > + regmap_update_bits(priv->regmap, priv->phy_reg_offset, > + BIT(priv->reg_bits->slave_endianness), 0); > + regmap_update_bits(priv->regmap, priv->phy_reg_offset, > + BIT(priv->reg_bits->host_endianness), > + BIT(priv->reg_bits->host_endianness)); > + > + /* Reset USB core throgh reset controller */ > + reset_control_deassert(priv->ctrl_reset); > + > + if (priv->phy_reset) > + reset_control_assert(priv->phy_reset); > +} > + > +static int ltq_rcu_usb2_get_vbus_gpios(struct device *dev, > + struct gpio_desc **gpios) > +{ > + int i; > + > + for (i = 0; i < MAX_VBUS_GPIO; i++) { > + gpios[i] = devm_gpiod_get_index_optional(dev, "vbus", i, > + GPIOD_OUT_LOW); > + if (IS_ERR(gpios[i])) > + return PTR_ERR(gpios[i]); > + } > + > + return 0; > +} > + > +static int ltq_rcu_usb2_of_probe(struct device_node *phynode, > + struct ltq_rcu_usb2_priv *priv) > +{ > + struct device *dev = priv->dev; > + const struct of_device_id *match = > + of_match_node(ltq_rcu_usb2_phy_of_match, phynode); > + int ret; > + > + if (!match) { > + dev_err(dev, "Not a compatible Lantiq RCU USB PHY\n"); > + return -EINVAL; > + } > + > + priv->reg_bits = match->data; > + > + priv->regmap = syscon_regmap_lookup_by_phandle(phynode, > + "lantiq,rcu-syscon"); > + if (IS_ERR(priv->regmap)) { > + dev_err(dev, "Failed to lookup RCU regmap\n"); > + return PTR_ERR(priv->regmap); > + } > + > + ret = ltq_rcu_usb2_get_vbus_gpios(dev, priv->gpiod_vbus); > + if (ret) { > + dev_err(dev, "failed to request shared USB VBUS GPIO\n"); > + return ret; > + } > + > + priv->ctrl_gate_clk = devm_clk_get(dev, "ctrl"); > + if (IS_ERR(priv->ctrl_gate_clk)) { > + dev_err(dev, "Unable to get USB ctrl gate clk\n"); > + return PTR_ERR(priv->ctrl_gate_clk); > + } > + > + priv->phy_gate_clk = devm_clk_get(dev, "phy"); > + if (IS_ERR(priv->phy_gate_clk)) { > + dev_err(dev, "Unable to get USB phy gate clk\n"); > + return PTR_ERR(priv->phy_gate_clk); > + } > + > + priv->ctrl_reset = devm_reset_control_get_shared(dev, "ctrl"); > + if (IS_ERR(priv->ctrl_reset)) { > + dev_err(dev, "failed to get 'ctrl' reset\n"); > + return PTR_ERR(priv->ctrl_reset); > + } > + > + priv->phy_reset = devm_reset_control_get_optional(dev, "phy"); > + if (IS_ERR(priv->phy_reset)) { > + if (PTR_ERR(priv->phy_reset) == -EPROBE_DEFER) > + return PTR_ERR(priv->phy_reset); > + priv->phy_reset = NULL; > + } a recent reset controller framework improvement allows us to make this much easier as: "As of commit bb475230b8e5 ("reset: make optional functions really optional"), the reset framework API calls use NULL pointers to describe optional, non-present reset controls." (see [0]) so we can basically turn this into IS_ERR() then return PTR_ERR() > + ret = of_property_read_u32_index(phynode, "lantiq,rcu-syscon", 1, > + &priv->phy_reg_offset); > + if (ret) { > + dev_err(dev, "Failed to get RCU PHY reg offset\n"); > + return ret; > + } > + > + if (priv->reg_bits->have_ana_cfg) { > + ret = of_property_read_u32_index(phynode, "lantiq,rcu-syscon", > + 2, &priv->ana_cfg1_reg_offset); > + if (ret) { > + dev_dbg(dev, "Failed to get RCU ANA CFG1 reg offset\n"); > + return ret; > + } > + } > + > + return 0; > +} > + > +static int ltq_rcu_usb2_phy_probe(struct platform_device *pdev) > +{ > + struct device_node *child, *np = pdev->dev.of_node; > + struct ltq_rcu_usb2_priv *priv; > + struct phy_provider *provider; > + int ret; > + > + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), > + GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + priv->dev = &pdev->dev; > + dev_set_drvdata(priv->dev, priv); > + > + ret = ltq_rcu_usb2_of_probe(np, priv); > + if (ret) > + return ret; > + > + priv->phy = devm_phy_create(&pdev->dev, child, > + <q_rcu_usb2_phy_ops); > + if (IS_ERR(priv->phy)) { > + dev_err(&pdev->dev, "failed to create PHY\n"); > + return PTR_ERR(priv->phy); > + } > + > + phy_set_drvdata(priv->phy, priv); > + > + ltq_rcu_usb2_start_cores(pdev); > + > + provider = devm_of_phy_provider_register(&pdev->dev, > + of_phy_simple_xlate); > + > + return PTR_ERR_OR_ZERO(provider); > +} > + > +static struct platform_driver ltq_rcu_usb2_phy_driver = { > + .probe = ltq_rcu_usb2_phy_probe, > + .driver = { > + .name = "lantiq-rcu-usb2-phy", > + .of_match_table = ltq_rcu_usb2_phy_of_match, > + } > +}; > +module_platform_driver(ltq_rcu_usb2_phy_driver); > + > +MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>"); > +MODULE_DESCRIPTION("Lantiq XWAY USB2 PHY driver"); > +MODULE_LICENSE("GPL v2"); > -- > 2.11.0 > [0] https://patchwork.kernel.org/patch/9545031/ [1] http://lxr.free-electrons.com/source/drivers/phy/phy-core.c#L276