Re: [PATCH v3] phy: Add new Exynos5 USB 3.0 PHY driver

Kishon Vijay Abraham I
2014-01-27T08:57:07Z

Hi,

On Monday 20 January 2014 07:12 PM, Vivek Gautam wrote:
> Add a new driver for the USB 3.0 PHY on Exynos5 series of SoCs.
> The new driver uses the generic PHY framework and will interact
> with DWC3 controller present on Exynos5 series of SoCs.
> Thereby, removing old phy-samsung-usb3 driver and related code
> used untill now which was based on usb/phy framework.
>
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> ---
>
> Changes from v2:
> 1) Added support for multiple PHYs (UTMI+ and PIPE3) and
> related changes in the driver structuring.
> 2) Added a xlate function to get the required phy out of
> number of PHYs in mutiple PHY scenerio.
> 3) Changed the names of few structures and variables to
> have a clearer meaning.
> 4) Added 'usb3phy_config' structure to take care of mutiple
> phys for a SoC having 'exynos5_usb3phy_drv_data' driver data.
> 5) Not deleting support for old driver 'phy-samsung-usb3' until
> required support for generic phy is added to DWC3.
>
> .../devicetree/bindings/phy/samsung-phy.txt | 49 ++
> drivers/phy/Kconfig | 8 +
> drivers/phy/Makefile | 1 +
> drivers/phy/phy-exynos5-usb3.c | 621 ++++++++++++++++++++
> 4 files changed, 679 insertions(+)
> create mode 100644 drivers/phy/phy-exynos5-usb3.c
>
> diff --git a/Documentation/devicetree/bindings/phy/samsung-phy.txt b/Documentation/devicetree/bindings/phy/samsung-phy.txt
> index c0fccaa..57079f8 100644
> --- a/Documentation/devicetree/bindings/phy/samsung-phy.txt
> +++ b/Documentation/devicetree/bindings/phy/samsung-phy.txt
> @@ -20,3 +20,52 @@ Required properties:
> - compatible : should be "samsung,exynos5250-dp-video-phy";
> - reg : offset and length of the Display Port PHY register set;
> - #phy-cells : from the generic PHY bindings, must be 0;
> +
> +Samsung Exynos5 SoC series USB 3.0 PHY controller
> +--------------------------------------------------
> +
> +Required properties:
> +- compatible : Should be set to one of the following supported values:
> + - "samsung,exynos5250-usb3phy" - for exynos5250 SoC,
> + - "samsung,exynos5420-usb3phy" - for exynos5420 SoC.
> +- reg : Register offset and length of USB 3.0 PHY register set;
> +- clocks: Clock IDs array as required by the controller
> +- clock-names: names of clocks correseponding to IDs in the clock property;
> + Required clocks:
> + - phy: main PHY clock (same as USB 3.0 controller IP clock),
> + used for register access.
> + - usb3phy_refclk: PHY's reference clock (usually crystal clock),
> + associated by phy name, used to determine bit values for
> + clock settings register.
> + Additional clock required for Exynos5420:
> + - usb30_sclk_100m: Additional special clock used for PHY operation
> + depicted as 'sclk_usbphy30' in CMU of Exynos5420.
> +- samsung,syscon-phandle: phandle for syscon interface, which is used to
> + control pmu registers for power isolation.
> +- #phy-cells : from the generic PHY bindings, must be 1;
> +
> +For "samsung,exynos5250-usb3phy" and "samsung,exynos5420-usb3phy" compatible
> +PHYs, the second cell in the PHY specifier identifies the PHY id, which is
> +interpreted as follows:
> + 0 - UTMI+ type phy,
> + 1 - PIPE3 type phy,
> +
> +Example:
> + usb3_phy: usbphy@12100000 {
> + compatible = "samsung,exynos5250-usb3phy";
> + reg = <0x12100000 0x100>;
> + clocks = <&clock 286>, <&clock 1>;
> + clock-names = "phy", "usb3phy_refclk";
> + samsung,syscon-phandle = <&pmu_syscon>;
> + #phy-cells = <1>;
> + };
> +
> +- aliases: For SoCs like Exynos5420 having multiple USB PHY controllers,
> + 'usb3_phy' nodes should have numbered alias in the aliases node,
> + in the form of usb3phyN, N = 0, 1... (depending on number of
> + controllers).
> +Example:
> + aliases {
> + usb3phy0 = &usb3_phy0;
> + usb3phy1 = &usb3_phy1;
> + };
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 330ef2d..32f9f38 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -51,4 +51,12 @@ config PHY_EXYNOS_DP_VIDEO
> help
> Support for Display Port PHY found on Samsung EXYNOS SoCs.
>
> +config PHY_EXYNOS5_USB3
> + tristate "Exynos5 SoC series USB 3.0 PHY driver"
> + depends on ARCH_EXYNOS5
> + select GENERIC_PHY
> + select MFD_SYSCON

add depends on 'HAS_IOMEM'. Someone reported getting
undefined reference to `devm_ioremap_resource' with it.
> + help
> + Enable USB 3.0 PHY support for Exynos 5 SoC series
> +
> endmenu
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index d0caae9..9c06a61 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -7,3 +7,4 @@ obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO) += phy-exynos-dp-video.o
> obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO) += phy-exynos-mipi-video.o
> obj-$(CONFIG_OMAP_USB2) += phy-omap-usb2.o
> obj-$(CONFIG_TWL4030_USB) += phy-twl4030-usb.o
> +obj-$(CONFIG_PHY_EXYNOS5_USB3) += phy-exynos5-usb3.o
> diff --git a/drivers/phy/phy-exynos5-usb3.c b/drivers/phy/phy-exynos5-usb3.c
> new file mode 100644
> index 0000000..24efed0
> --- /dev/null
> +++ b/drivers/phy/phy-exynos5-usb3.c
> @@ -0,0 +1,621 @@
> +/*
> + * Samsung EXYNOS5 SoC series USB 3.0 PHY driver
> + *
> + * Copyright (C) 2013 Samsung Electronics Co., Ltd.
> + * Author: Vivek Gautam <gautam.vivek@samsung.com>
> + *
> + * 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/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/mutex.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +
> +/* Exynos USB PHY registers */
> +#define EXYNOS5_FSEL_9MHZ6 0x0
> +#define EXYNOS5_FSEL_10MHZ 0x1
> +#define EXYNOS5_FSEL_12MHZ 0x2
> +#define EXYNOS5_FSEL_19MHZ2 0x3
> +#define EXYNOS5_FSEL_20MHZ 0x4
> +#define EXYNOS5_FSEL_24MHZ 0x5
> +#define EXYNOS5_FSEL_50MHZ 0x7
> +
> +/* EXYNOS5: USB 3.0 DRD PHY registers */
> +#define EXYNOS5_DRD_LINKSYSTEM (0x04)
> +
> +#define LINKSYSTEM_FLADJ_MASK (0x3f << 1)
> +#define LINKSYSTEM_FLADJ(_x) ((_x) << 1)
> +#define LINKSYSTEM_XHCI_VERSION_CONTROL (0x1 << 27)
> +
> +#define EXYNOS5_DRD_PHYUTMI (0x08)
> +
> +#define PHYUTMI_OTGDISABLE (0x1 << 6)
> +#define PHYUTMI_FORCESUSPEND (0x1 << 1)
> +#define PHYUTMI_FORCESLEEP (0x1 << 0)

use BIT macro here and below?
> +
> +#define EXYNOS5_DRD_PHYPIPE (0x0c)
> +
> +#define EXYNOS5_DRD_PHYCLKRST (0x10)
> +
> +#define PHYCLKRST_EN_UTMISUSPEND (0x1 << 31)
> +
> +#define PHYCLKRST_SSC_REFCLKSEL_MASK (0xff << 23)
> +#define PHYCLKRST_SSC_REFCLKSEL(_x) ((_x) << 23)
> +
> +#define PHYCLKRST_SSC_RANGE_MASK (0x03 << 21)
> +#define PHYCLKRST_SSC_RANGE(_x) ((_x) << 21)
> +
> +#define PHYCLKRST_SSC_EN (0x1 << 20)
> +#define PHYCLKRST_REF_SSP_EN (0x1 << 19)
> +#define PHYCLKRST_REF_CLKDIV2 (0x1 << 18)
> +
> +#define PHYCLKRST_MPLL_MULTIPLIER_MASK (0x7f << 11)
> +#define PHYCLKRST_MPLL_MULTIPLIER_100MHZ_REF (0x19 << 11)
> +#define PHYCLKRST_MPLL_MULTIPLIER_50M_REF (0x32 << 11)
> +#define PHYCLKRST_MPLL_MULTIPLIER_24MHZ_REF (0x68 << 11)
> +#define PHYCLKRST_MPLL_MULTIPLIER_20MHZ_REF (0x7d << 11)
> +#define PHYCLKRST_MPLL_MULTIPLIER_19200KHZ_REF (0x02 << 11)
> +
> +#define PHYCLKRST_FSEL_MASK (0x3f << 5)
> +#define PHYCLKRST_FSEL(_x) ((_x) << 5)
> +#define PHYCLKRST_FSEL_PAD_100MHZ (0x27 << 5)
> +#define PHYCLKRST_FSEL_PAD_24MHZ (0x2a << 5)
> +#define PHYCLKRST_FSEL_PAD_20MHZ (0x31 << 5)
> +#define PHYCLKRST_FSEL_PAD_19_2MHZ (0x38 << 5)
> +
> +#define PHYCLKRST_RETENABLEN (0x1 << 4)
> +
> +#define PHYCLKRST_REFCLKSEL_MASK (0x03 << 2)
> +#define PHYCLKRST_REFCLKSEL_PAD_REFCLK (0x2 << 2)
> +#define PHYCLKRST_REFCLKSEL_EXT_REFCLK (0x3 << 2)
> +
> +#define PHYCLKRST_PORTRESET (0x1 << 1)
> +#define PHYCLKRST_COMMONONN (0x1 << 0)
> +
> +#define EXYNOS5_DRD_PHYREG0 (0x14)
> +#define EXYNOS5_DRD_PHYREG1 (0x18)
> +
> +#define EXYNOS5_DRD_PHYPARAM0 (0x1c)
> +
> +#define PHYPARAM0_REF_USE_PAD (0x1 << 31)
> +#define PHYPARAM0_REF_LOSLEVEL_MASK (0x1f << 26)
> +#define PHYPARAM0_REF_LOSLEVEL (0x9 << 26)
> +
> +#define EXYNOS5_DRD_PHYPARAM1 (0x20)
> +
> +#define PHYPARAM1_PCS_TXDEEMPH_MASK (0x1f << 0)
> +#define PHYPARAM1_PCS_TXDEEMPH (0x1c)
> +
> +#define EXYNOS5_DRD_PHYTERM (0x24)
> +
> +#define EXYNOS5_DRD_PHYTEST (0x28)
> +
> +#define PHYTEST_POWERDOWN_SSP (0x1 << 3)
> +#define PHYTEST_POWERDOWN_HSP (0x1 << 2)
> +
> +#define EXYNOS5_DRD_PHYADP (0x2c)
> +
> +#define EXYNOS5_DRD_PHYBATCHG (0x30)
> +
> +#define PHYBATCHG_UTMI_CLKSEL (0x1 << 2)
> +
> +#define EXYNOS5_DRD_PHYRESUME (0x34)
> +#define EXYNOS5_DRD_LINKPORT (0x44)
> +
> +/* Power isolation defined in power management unit */
> +#define EXYNOS5_USB3DRD_PHY_PMU_REG_OFFSET (0x704)
> +#define EXYNOS5_USB3DRD_PMU_ISOL (1 << 0)
> +
> +#define KHZ 1000
> +#define MHZ (KHZ * KHZ)
> +
> +enum exynos5_usb3phy_id {
> + EXYNOS5_USB3PHY_UTMI,
> + EXYNOS5_USB3PHY_PIPE3,
> + EXYNOS5_USB3PHYS_NUM,
> +};
> +
> +struct usb3phy_config {
> + u32 id;
> + u32 reg_pmu_offset;
> + void (*phy_isol)(struct phy *phy, u32 on);
> +};
> +
> +struct exynos5_usb3phy_drv_data {
> + bool has_usb30_sclk;
> + bool has_multi_controller;
> + const struct usb3phy_config *phy_cfg;
> +};
> +
> +/**
> + * struct exynos5_usb3phy_driver - driver data for USB 3.0 PHY

Is this really a driver data? I think it should be just exynos5_usb3phy.
> + * @dev: pointer to device instance of this platform device
> + * @reg_phy: usb phy controller register memory base
> + * @clk: phy clock for register access
> + * @usb30_sclk: additional special clock for phy operations
> + * @drv_data: pointer to SoC level driver data structure
> + * @phys[]: array for 'EXYNOS5_USB3PHYS_NUM' number of PHY
> + * instances each with its 'phy' and 'phy_cfg'.
> + * @extrefclk: frequency select settings when using 'separate
> + * reference clocks' for SS and HS operations
> + * @rate: rate of reference clock to PHY block
> + * @channel: number of PHY channels present in SoC
> + */
> +struct exynos5_usb3phy_driver {
> + struct device *dev;
> + void __iomem *reg_phy;
> + struct clk *clk;
> + struct clk *usb30_sclk;
> + const struct exynos5_usb3phy_drv_data *drv_data;
> + struct phy_usb_instance {
> + struct phy *phy;
> + u32 index;
> + struct regmap *reg_isol;
> + const struct usb3phy_config *phy_cfg;
> + } phys[EXYNOS5_USB3PHYS_NUM];
> + u32 extrefclk;
> + unsigned long rate;
> + u32 channel;
> +};
> +
> +#define to_usb3phy_driver(inst) \
> + container_of((inst), struct exynos5_usb3phy_driver, \
> + phys[(inst)->index]);
> +
> +/*
> + * exynos5_rate_to_clk() converts the supplied clock rate to the value that
> + * can be written to the phy register.
> + */
> +static u32 exynos5_rate_to_clk(unsigned long rate)
> +{
> + unsigned int clksel;
> +
> + /* EXYNOS5_FSEL_MASK */
> +
> + switch (rate) {
> + case 9600 * KHZ:
> + clksel = EXYNOS5_FSEL_9MHZ6;
> + break;
> + case 10 * MHZ:
> + clksel = EXYNOS5_FSEL_10MHZ;
> + break;
> + case 12 * MHZ:
> + clksel = EXYNOS5_FSEL_12MHZ;
> + break;
> + case 19200 * KHZ:
> + clksel = EXYNOS5_FSEL_19MHZ2;
> + break;
> + case 20 * MHZ:
> + clksel = EXYNOS5_FSEL_20MHZ;
> + break;
> + case 24 * MHZ:
> + clksel = EXYNOS5_FSEL_24MHZ;
> + break;
> + case 50 * MHZ:
> + clksel = EXYNOS5_FSEL_50MHZ;
> + break;
> + default:
> + clksel = -EINVAL;
> + }
> +
> + return clksel;
> +}
> +
> +static void exynos5_usb3phy_isol(struct phy *phy, unsigned int on)
> +{
> + u32 pmu_offset;
> + struct phy_usb_instance *inst = phy_get_drvdata(phy);
> + struct exynos5_usb3phy_driver *drv = to_usb3phy_driver(inst);
> +
> + pmu_offset = inst->phy_cfg->reg_pmu_offset;
> + if (!inst->reg_isol)
> + return;
> +
> + switch (drv->channel) {
> + case 1:
> + /* Channel 1 is at 0x708 offset */
> + pmu_offset += sizeof(&pmu_offset);
> + break;
> + case 0:
> + default:
> + /* Channel 0 is at 0x704 offset */
> + break;
> + }

This can be in a simple 'if' stmt no?
> +
> + regmap_update_bits(inst->reg_isol, pmu_offset,
> + EXYNOS5_USB3DRD_PMU_ISOL, ~on);
> +}
> +
> +/*
> + * Sets the phy clk as EXTREFCLK (XXTI) which is internal clock from clock core.
> + */
> +static u32 exynos5_usb3phy_set_refclk(struct exynos5_usb3phy_driver *drv)
> +{
> + u32 reg;
> +
> + reg = PHYCLKRST_REFCLKSEL_EXT_REFCLK |
> + PHYCLKRST_FSEL(drv->extrefclk);
> +
> + switch (drv->extrefclk) {
> + case EXYNOS5_FSEL_50MHZ:
> + reg |= (PHYCLKRST_MPLL_MULTIPLIER_50M_REF |
> + PHYCLKRST_SSC_REFCLKSEL(0x00));
> + break;
> + case EXYNOS5_FSEL_24MHZ:
> + reg |= (PHYCLKRST_MPLL_MULTIPLIER_24MHZ_REF |
> + PHYCLKRST_SSC_REFCLKSEL(0x88));
> + break;
> + case EXYNOS5_FSEL_20MHZ:
> + reg |= (PHYCLKRST_MPLL_MULTIPLIER_20MHZ_REF |
> + PHYCLKRST_SSC_REFCLKSEL(0x00));
> + break;
> + case EXYNOS5_FSEL_19MHZ2:
> + reg |= (PHYCLKRST_MPLL_MULTIPLIER_19200KHZ_REF |
> + PHYCLKRST_SSC_REFCLKSEL(0x88));
> + break;
> + default:
> + dev_dbg(drv->dev, "unsupported ref clk\n");
> + break;
> + }
> +
> + return reg;
> +}
> +
> +static int exynos5_usb3phy_init(struct phy *phy)
> +{
> + int ret;
> + u32 phyparam0;
> + u32 phyparam1;
> + u32 linksystem;
> + u32 phybatchg;
> + u32 phytest;
> + u32 phyclkrst;

instead you can define a single variable 'u32 reg' for register read and writes.
> + struct phy_usb_instance *inst = phy_get_drvdata(phy);
> + struct exynos5_usb3phy_driver *drv = to_usb3phy_driver(inst);
> +
> + ret = clk_prepare_enable(drv->clk);
> + if (ret)
> + return ret;
> +
> + drv->extrefclk = exynos5_rate_to_clk(drv->rate);
> + if (drv->extrefclk == -EINVAL) {
> + dev_err(drv->dev, "Clock rate (%ld) not supported\n",
> + drv->rate);
> + return -EINVAL;
> + }
> +
> + /* Reset USB 3.0 PHY */
> + writel(0x0, drv->reg_phy + EXYNOS5_DRD_PHYREG0);
> +
> + phyparam0 = readl(drv->reg_phy + EXYNOS5_DRD_PHYPARAM0);
> + /* Select PHY CLK source */
> + phyparam0 &= ~PHYPARAM0_REF_USE_PAD;
> + /* Set Loss-of-Signal Detector sensitivity */
> + phyparam0 &= ~PHYPARAM0_REF_LOSLEVEL_MASK;
> + phyparam0 |= PHYPARAM0_REF_LOSLEVEL;
> + writel(phyparam0, drv->reg_phy + EXYNOS5_DRD_PHYPARAM0);
> +
> + writel(0x0, drv->reg_phy + EXYNOS5_DRD_PHYRESUME);
> +
> + /*
> + * Setting the Frame length Adj value[6:1] to default 0x20
> + * See xHCI 1.0 spec, 5.2.4
> + */
> + linksystem = LINKSYSTEM_XHCI_VERSION_CONTROL |
> + LINKSYSTEM_FLADJ(0x20);
> + writel(linksystem, drv->reg_phy + EXYNOS5_DRD_LINKSYSTEM);
> +
> + phyparam1 = readl(drv->reg_phy + EXYNOS5_DRD_PHYPARAM1);
> + /* Set Tx De-Emphasis level */
> + phyparam1 &= ~PHYPARAM1_PCS_TXDEEMPH_MASK;
> + phyparam1 |= PHYPARAM1_PCS_TXDEEMPH;
> + writel(phyparam1, drv->reg_phy + EXYNOS5_DRD_PHYPARAM1);
> +
> + phybatchg = readl(drv->reg_phy + EXYNOS5_DRD_PHYBATCHG);
> + phybatchg |= PHYBATCHG_UTMI_CLKSEL;
> + writel(phybatchg, drv->reg_phy + EXYNOS5_DRD_PHYBATCHG);
> +
> + /* PHYTEST POWERDOWN Control */
> + phytest = readl(drv->reg_phy + EXYNOS5_DRD_PHYTEST);
> + phytest &= ~(PHYTEST_POWERDOWN_SSP |
> + PHYTEST_POWERDOWN_HSP);
> + writel(phytest, drv->reg_phy + EXYNOS5_DRD_PHYTEST);
> +
> + /* UTMI Power Control */
> + writel(PHYUTMI_OTGDISABLE, drv->reg_phy + EXYNOS5_DRD_PHYUTMI);

All these UTMI configuration should be done in usb2 init.
> +
> + phyclkrst = exynos5_usb3phy_set_refclk(drv);
> +
> + phyclkrst |= PHYCLKRST_PORTRESET |
> + /* Digital power supply in normal operating mode */
> + PHYCLKRST_RETENABLEN |
> + /* Enable ref clock for SS function */
> + PHYCLKRST_REF_SSP_EN |
> + /* Enable spread spectrum */
> + PHYCLKRST_SSC_EN |
> + /* Power down HS Bias and PLL blocks in suspend mode */
> + PHYCLKRST_COMMONONN;
> +
> + writel(phyclkrst, drv->reg_phy + EXYNOS5_DRD_PHYCLKRST);
> +
> + udelay(10);
> +
> + phyclkrst &= ~PHYCLKRST_PORTRESET;
> + writel(phyclkrst, drv->reg_phy + EXYNOS5_DRD_PHYCLKRST);
> +
> + clk_disable_unprepare(drv->clk);
> +
> + return 0;
> +}
> +
> +static int exynos5_usb3phy_exit(struct phy *phy)
> +{
> + int ret;
> + u32 phyutmi;
> + u32 phyclkrst;
> + u32 phytest;

same here..
> + struct phy_usb_instance *inst = phy_get_drvdata(phy);
> + struct exynos5_usb3phy_driver *drv = to_usb3phy_driver(inst);
> +
> + ret = clk_prepare_enable(drv->clk);
> + if (ret)
> + return ret;
> +
> + phyutmi = PHYUTMI_OTGDISABLE |
> + PHYUTMI_FORCESUSPEND |
> + PHYUTMI_FORCESLEEP;
> + writel(phyutmi, drv->reg_phy + EXYNOS5_DRD_PHYUTMI);

here too.. UTMI configuration should be part of USB2.
> +
> + /* Resetting the PHYCLKRST enable bits to reduce leakage current */
> + phyclkrst = readl(drv->reg_phy + EXYNOS5_DRD_PHYCLKRST);
> + phyclkrst &= ~(PHYCLKRST_REF_SSP_EN |
> + PHYCLKRST_SSC_EN |
> + PHYCLKRST_COMMONONN);
> + writel(phyclkrst, drv->reg_phy + EXYNOS5_DRD_PHYCLKRST);
> +
> + /* Control PHYTEST to remove leakage current */
> + phytest = readl(drv->reg_phy + EXYNOS5_DRD_PHYTEST);
> + phytest |= PHYTEST_POWERDOWN_SSP |
> + PHYTEST_POWERDOWN_HSP;
> + writel(phytest, drv->reg_phy + EXYNOS5_DRD_PHYTEST);
> +
> + clk_disable_unprepare(drv->clk);
> +
> + return 0;
> +}
> +
> +static int exynos5_usb3phy_power_on(struct phy *phy)
> +{
> + struct phy_usb_instance *inst = phy_get_drvdata(phy);
> + struct exynos5_usb3phy_driver *drv = to_usb3phy_driver(inst);
> +
> + dev_dbg(drv->dev, "Request to power_on usb3drd phy\n");
> +
> + if (!IS_ERR(drv->usb30_sclk))
> + clk_prepare_enable(drv->usb30_sclk);
> +
> + /* Power-on PHY*/
> + inst->phy_cfg->phy_isol(phy, 0);
> +
> + return 0;
> +}
> +
> +static int exynos5_usb3phy_power_off(struct phy *phy)
> +{
> + struct phy_usb_instance *inst = phy_get_drvdata(phy);
> + struct exynos5_usb3phy_driver *drv = to_usb3phy_driver(inst);
> +
> + dev_dbg(drv->dev, "Request to power_off usb3drd phy\n");
> +
> + /* Power-off the PHY */
> + inst->phy_cfg->phy_isol(phy, 1);
> +
> + if (!IS_ERR(drv->usb30_sclk))
> + clk_disable_unprepare(drv->usb30_sclk);
> +
> + return 0;
> +}
> +
> +static struct phy *exynos5_usb3phy_xlate(struct device *dev,
> + struct of_phandle_args *args)
> +{
> + struct exynos5_usb3phy_driver *drv = dev_get_drvdata(dev);
> +
> + if (WARN_ON(args->args[0] > EXYNOS5_USB3PHYS_NUM))
> + return ERR_PTR(-ENODEV);
> +
> + return drv->phys[args->args[0]].phy;
> +}
> +
> +static struct phy_ops exynos5_usb3phy_ops = {
> + .init = exynos5_usb3phy_init,
> + .exit = exynos5_usb3phy_exit,
> + .power_on = exynos5_usb3phy_power_on,
> + .power_off = exynos5_usb3phy_power_off,
> + .owner = THIS_MODULE,
> +};
> +
> +const struct usb3phy_config exynos5_usb3phy_cfg[] = {
> + {
> + .id = EXYNOS5_USB3PHY_UTMI,

This should be USB2 no?
> + .reg_pmu_offset = EXYNOS5_USB3DRD_PHY_PMU_REG_OFFSET,
> + .phy_isol = exynos5_usb3phy_isol,
> + },
> + {
> + .id = EXYNOS5_USB3PHY_PIPE3,
> + .reg_pmu_offset = EXYNOS5_USB3DRD_PHY_PMU_REG_OFFSET,
> + .phy_isol = exynos5_usb3phy_isol,
> + },
> + {},
> +};
> +
> +const struct exynos5_usb3phy_drv_data exynos5420_usb3phy = {
> + .has_usb30_sclk = true,
> + .has_multi_controller = true,
> + .phy_cfg = exynos5_usb3phy_cfg,
> +};
> +
> +const struct exynos5_usb3phy_drv_data exynos5250_usb3phy = {
> + .has_usb30_sclk = false,
> + .has_multi_controller = false,
> + .phy_cfg = exynos5_usb3phy_cfg,
> +};
> +
> +static const struct of_device_id exynos5_usb3phy_of_match[] = {
> + {
> + .compatible = "samsung,exynos5250-usb3phy",
> + .data = &exynos5250_usb3phy
> + }, {
> + .compatible = "samsung,exynos5420-usb3phy",
> + .data = &exynos5420_usb3phy
> + },
> + { },
> +};
> +
> +static int exynos5_usb3phy_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *node = dev->of_node;
> + struct exynos5_usb3phy_driver *drv;
> + struct phy_provider *phy_provider;
> + struct resource *res;
> + struct clk *clk;
> + const struct of_device_id *match;
> + const struct exynos5_usb3phy_drv_data *drv_data;
> + struct regmap *reg_isol;
> + int i;
> +
> + /*
> + * Exynos systems are completely DT enabled,
> + * so lets not have any platform data support for this driver.
> + */

Then you should add depend on OF for this driver.
> + if (!node) {
> + dev_err(dev, "no device node found\n");
> + return -ENODEV;
> + }
> +
> + match = of_match_node(exynos5_usb3phy_of_match, pdev->dev.of_node);
> + if (!match) {
> + dev_err(dev, "of_match_node() failed\n");
> + return -EINVAL;
> + }
> + drv_data = match->data;
> +
> + drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
> + if (!drv) {
> + dev_err(dev, "Failed to allocate memory\n");

dev_err is not needed here.
> + return -ENOMEM;
> + }
> +
> + dev_set_drvdata(dev, drv);
> + drv->dev = dev;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + drv->reg_phy = devm_ioremap_resource(dev, res);
> + if (IS_ERR(drv->reg_phy)) {
> + dev_err(dev, "Failed to map register memory (phy)\n");
> + return PTR_ERR(drv->reg_phy);
> + }
> +
> + drv->drv_data = drv_data;
> +
> + /*
> + * Exynos5420 SoC has multiple channels for USB 3.0 PHY, with
> + * each having separate power control registers.
> + * 'drv->channel' facilitates to set such registers.
> + */
> + if (drv->drv_data->has_multi_controller) {
> + drv->channel = of_alias_get_id(node, "usb3phy");
> + if (drv->channel < 0) {
> + dev_err(dev, "Invalid usb3drd phy node\n");
> + return -EINVAL;
> + }
> + }
> +
> + drv->clk = devm_clk_get(dev, "phy");
> + if (IS_ERR(drv->clk)) {
> + dev_err(dev, "Failed to get clock of phy controller\n");
> + return PTR_ERR(drv->clk);
> + }
> +
> + /*
> + * Exysno5420 SoC has an additional special clock, used for
> + * for USB 3.0 PHY operation, this clock goes to the PHY block
> + * as a reference clock to clock generation block of the controller,
> + * named as 'USB30_SCLK_100M'.
> + */
> + if (drv_data->has_usb30_sclk) {
> + drv->usb30_sclk = devm_clk_get(dev, "usb30_sclk_100m");
> + if (IS_ERR(drv->usb30_sclk)) {
> + dev_err(dev, "Failed to get phy reference clock\n");
> + return PTR_ERR(drv->usb30_sclk);
> + }
> + }
> +
> + clk = clk_get(dev, "usb3phy_refclk");
> + if (IS_ERR(clk)) {
> + dev_err(dev, "Failed to get reference clock of usb3drd phy\n");
> + return PTR_ERR(clk);
> + }
> + drv->rate = clk_get_rate(clk);
> + clk_put(clk);
> +
> + dev_dbg(dev, "Creating usb3drd phy\n");
dev_vdbg?

Cheers
Kishon