Subject: Re: [PATCH v2 05/10] phy: add A3700 UTMI PHY driver

From: Miquel Raynal <[email-masked]>
Date: Mon, 21 Jan 2019 11:37:16 +0100

Hi Kishon, Chunfeng,

Kishon Vijay Abraham I <[email-masked]> wrote on Wed, 16 Jan 2019
14:50:58 +0530:

> Hi,
> 
> On 15/01/19 8:10 AM, Chunfeng Yun wrote:
> > Hi,
> > On Fri, 2019-01-11 at 14:31 +0100, Miquel Raynal wrote:  
> >> Marvell Armada 3700 SoC has two USB controllers, each of them being
> >> wired to an internal UTMI PHY. Add a driver to control them.
> >>
> >> Igal Liberman worked on supporting the PHY, I took the while 'register
> >> configuration' from his work and rewrote almost entirely the
> >> driver/bindings around it.
> >>
> >> Co-developed-by: Igal Liberman <[email-masked]>
> >> Signed-off-by: Miquel Raynal <[email-masked]>
> >> Signed-off-by: Igal Liberman <[email-masked]>
> >> ---
> >>  drivers/phy/marvell/Kconfig                |   9 +
> >>  drivers/phy/marvell/Makefile               |   1 +
> >>  drivers/phy/marvell/phy-mvebu-a3700-utmi.c | 297 +++++++++++++++++++++
> >>  3 files changed, 307 insertions(+)
> >>  create mode 100644 drivers/phy/marvell/phy-mvebu-a3700-utmi.c
> >>
> >> diff --git a/drivers/phy/marvell/Kconfig b/drivers/phy/marvell/Kconfig
> >> index 9c90c0408ea3..b8e9dd38ad0d 100644
> >> --- a/drivers/phy/marvell/Kconfig
> >> +++ b/drivers/phy/marvell/Kconfig
> >> @@ -33,6 +33,15 @@ config PHY_MVEBU_A3700_COMPHY
> >>  	  shared serdes PHYs on Marvell Armada 3700. Its serdes lanes can be
> >>  	  used by various controllers: Ethernet, SATA, USB3, PCIe.
> >>  
> >> +config PHY_MVEBU_A3700_UTMI
> >> +	tristate "Marvell A3700 UTMI driver"
> >> +	depends on ARCH_MVEBU || COMPILE_TEST
> >> +	depends on OF
> >> +	default y
> >> +	select GENERIC_PHY
> >> +	help
> >> +	  Enable this to support Marvell A3700 UTMI PHY driver.
> >> +
> >>  config PHY_MVEBU_CP110_COMPHY
> >>  	tristate "Marvell CP110 comphy driver"
> >>  	depends on ARCH_MVEBU || COMPILE_TEST
> >> diff --git a/drivers/phy/marvell/Makefile b/drivers/phy/marvell/Makefile
> >> index c13a0c8ab6f0..82f291cf59ee 100644
> >> --- a/drivers/phy/marvell/Makefile
> >> +++ b/drivers/phy/marvell/Makefile
> >> @@ -3,6 +3,7 @@ obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY)	+= phy-armada375-usb2.o
> >>  obj-$(CONFIG_PHY_BERLIN_SATA)		+= phy-berlin-sata.o
> >>  obj-$(CONFIG_PHY_BERLIN_USB)		+= phy-berlin-usb.o
> >>  obj-$(CONFIG_PHY_MVEBU_A3700_COMPHY)	+= phy-mvebu-a3700-comphy.o
> >> +obj-$(CONFIG_PHY_MVEBU_A3700_UTMI)	+= phy-mvebu-a3700-utmi.o
> >>  obj-$(CONFIG_PHY_MVEBU_CP110_COMPHY)	+= phy-mvebu-cp110-comphy.o
> >>  obj-$(CONFIG_PHY_MVEBU_SATA)		+= phy-mvebu-sata.o
> >>  obj-$(CONFIG_PHY_PXA_28NM_HSIC)		+= phy-pxa-28nm-hsic.o
> >> diff --git a/drivers/phy/marvell/phy-mvebu-a3700-utmi.c b/drivers/phy/marvell/phy-mvebu-a3700-utmi.c
> >> new file mode 100644
> >> index 000000000000..97d8235d661d
> >> --- /dev/null
> >> +++ b/drivers/phy/marvell/phy-mvebu-a3700-utmi.c
> >> @@ -0,0 +1,297 @@
> >> +// SPDX-License-Identifier: GPL-2.0
> >> +/*
> >> + * Copyright (C) 2018 Marvell
> >> + *
> >> + * Authors:
> >> + *   Evan Wang <[email-masked]>
> >> + *   Miquèl Raynal <[email-masked]>
> >> + *
> >> + * Marvell A3700 UTMI PHY driver
> >> + */
> >> +
> >> +#include <linux/io.h>
> >> +#include <linux/iopoll.h>
> >> +#include <linux/mfd/syscon.h>
> >> +#include <linux/module.h>
> >> +#include <linux/of_device.h>
> >> +#include <linux/phy/phy.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/regmap.h>
> >> +
> >> +/* Armada 3700 UTMI PHY registers */
> >> +#define USB2_PHY_PLL_CTRL_REG0			0x0
> >> +#define   PLL_REF_DIV_OFF			0
> >> +#define   PLL_REF_DIV_MASK			(0x7F << PLL_REF_DIV_OFF)  
> > use GENMASK?  

Ok

> >> +#define   PLL_REF_DIV_5				0x5
> >> +#define   PLL_FB_DIV_OFF			16
> >> +#define   PLL_FB_DIV_MASK			(0x1FF << PLL_FB_DIV_OFF)
> >> +#define   PLL_FB_DIV_96				96
> >> +#define   PLL_SEL_LPFR_OFF			28
> >> +#define   PLL_SEL_LPFR_MASK			(0x3 << PLL_SEL_LPFR_OFF)
> >> +#define   PLL_READY				BIT(31)
> >> +#define USB2_PHY_CAL_CTRL			0x8
> >> +#define   PHY_PLLCAL_DONE			BIT(31)
> >> +#define   PHY_IMPCAL_DONE			BIT(23)
> >> +#define USB2_RX_CHAN_CTRL1			0x18
> >> +#define   USB2PHY_SQCAL_DONE			BIT(31)
> >> +#define USB2_PHY_OTG_CTRL			0x34
> >> +#define   PHY_PU_OTG				BIT(4)
> >> +#define USB2_PHY_CHRGR_DETECT			0x38
> >> +#define   PHY_CDP_EN				BIT(2)
> >> +#define   PHY_DCP_EN				BIT(3)
> >> +#define   PHY_PD_EN				BIT(4)
> >> +#define   PHY_PU_CHRG_DTC			BIT(5)
> >> +#define   PHY_CDP_DM_AUTO			BIT(7)
> >> +#define   PHY_ENSWITCH_DP			BIT(12)
> >> +#define   PHY_ENSWITCH_DM			BIT(13)
> >> +
> >> +/* Armada 3700 USB miscellaneous registers */
> >> +#define USB2_PHY_CTRL(usb32)			(usb32 ? 0x20 : 0x4)
> >> +#define   RB_USB2PHY_PU				BIT(0)
> >> +#define   USB2_DP_PULLDN_DEV_MODE		BIT(5)
> >> +#define   USB2_DM_PULLDN_DEV_MODE		BIT(6)
> >> +#define   RB_USB2PHY_SUSPM(usb32)		(usb32 ? BIT(14) : BIT(7))
> >> +
> >> +#define PLL_LOCK_DELAY_US			10000
> >> +#define PLL_LOCK_TIMEOUT_US			1000000
> >> +
> >> +/**
> >> + * struct mvebu_a3700_utmi_caps - PHY capabilities
> >> + *
> >> + * @usb32: Flag indicating which PHY is in use (impacts the register map):
> >> + *           - The UTMI PHY wired to the USB3/USB2 controller (otg)
> >> + *           - The UTMI PHY wired to the USB2 controller (host only)
> >> + * @ops: PHY operations
> >> + */
> >> +struct mvebu_a3700_utmi_caps {
> >> +	int usb32;
> >> +	const struct phy_ops *ops;
> >> +};
> >> +
> >> +/**
> >> + * struct mvebu_a3700_utmi - PHY driver data
> >> + *
> >> + * @regs: PHY registers
> >> + * @usb_mis: Regmap with USB miscellaneous registers including PHY ones
> >> + * @caps: PHY capabilities
> >> + * @phy: PHY handle
> >> + */
> >> +struct mvebu_a3700_utmi {
> >> +	void __iomem *regs;
> >> +	struct regmap *usb_misc;
> >> +	const struct mvebu_a3700_utmi_caps *caps;
> >> +	struct phy *phy;
> >> +};
> >> +
> >> +static int mvebu_a3700_utmi_phy_power_on(struct phy *phy)
> >> +{
> >> +	struct mvebu_a3700_utmi *utmi = phy_get_drvdata(phy);
> >> +	struct device *dev = &phy->dev;
> >> +	int usb32 = utmi->caps->usb32;
> >> +	int ret = 0;
> >> +	u32 reg;
> >> +
> >> +	if (!utmi)
> >> +		return -ENODEV;  
> > the check here may be not necessary  
> 
> right. utmi is already referenced above.

Removed.

> >> +
> >> +	/*
> >> +	 * Setup PLL. 40MHz clock used to be the default, bein 25MHz now.
> >> +	 * See "PLL Settings for Typical REFCLK" table.
> >> +	 */
> >> +	reg = readl(utmi->regs + USB2_PHY_PLL_CTRL_REG0);
> >> +	reg &= ~(PLL_REF_DIV_MASK | PLL_FB_DIV_MASK | PLL_SEL_LPFR_MASK);
> >> +	reg |= (PLL_REF_DIV_5 << PLL_REF_DIV_OFF |
> >> +		PLL_FB_DIV_96 << PLL_FB_DIV_OFF);
> >> +	writel(reg, utmi->regs + USB2_PHY_PLL_CTRL_REG0);
> >> +
> >> +	/* Enable PHY pull up and disable USB2 suspend */
> >> +	regmap_update_bits(utmi->usb_misc, USB2_PHY_CTRL(usb32),
> >> +			   RB_USB2PHY_SUSPM(usb32) | RB_USB2PHY_PU,
> >> +			   RB_USB2PHY_SUSPM(usb32) | RB_USB2PHY_PU);
> >> +
> >> +	if (usb32) {
> >> +		/* Power up OTG module */
> >> +		reg = readl(utmi->regs + USB2_PHY_OTG_CTRL);
> >> +		reg |= PHY_PU_OTG;
> >> +		writel(reg, utmi->regs + USB2_PHY_OTG_CTRL);
> >> +
> >> +		/* Disable PHY charger detection */
> >> +		reg = readl(utmi->regs + USB2_PHY_CHRGR_DETECT);
> >> +		reg &= ~(PHY_CDP_EN | PHY_DCP_EN | PHY_PD_EN | PHY_PU_CHRG_DTC |
> >> +			 PHY_CDP_DM_AUTO | PHY_ENSWITCH_DP | PHY_ENSWITCH_DM);
> >> +		writel(reg, utmi->regs + USB2_PHY_CHRGR_DETECT);
> >> +
> >> +		/* Disable PHY DP/DM pull-down (used for device mode) */
> >> +		regmap_update_bits(utmi->usb_misc, USB2_PHY_CTRL(usb32),
> >> +				   USB2_DP_PULLDN_DEV_MODE |
> >> +				   USB2_DM_PULLDN_DEV_MODE, 0);
> >> +	}
> >> +
> >> +	/* Wait for PLL calibration */
> >> +	ret = readl_poll_timeout(utmi->regs + USB2_PHY_CAL_CTRL, reg,
> >> +				 reg & PHY_PLLCAL_DONE,
> >> +				 PLL_LOCK_DELAY_US, PLL_LOCK_TIMEOUT_US);
> >> +	if (ret) {
> >> +		dev_err(dev, "Failed to end USB2 PLL calibration\n");
> >> +		return ret;
> >> +	}
> >> +
> >> +	/* Wait for impedance calibration */
> >> +	ret = readl_poll_timeout(utmi->regs + USB2_PHY_CAL_CTRL, reg,
> >> +				 reg & PHY_IMPCAL_DONE,
> >> +				 PLL_LOCK_DELAY_US, PLL_LOCK_TIMEOUT_US);
> >> +	if (ret) {
> >> +		dev_err(dev, "Failed to end USB2 impedance calibration\n");
> >> +		return ret;
> >> +	}
> >> +
> >> +	/* Wait for squetch calibration */
> >> +	ret = readl_poll_timeout(utmi->regs + USB2_RX_CHAN_CTRL1, reg,
> >> +				 reg & USB2PHY_SQCAL_DONE,
> >> +				 PLL_LOCK_DELAY_US, PLL_LOCK_TIMEOUT_US);
> >> +	if (ret) {
> >> +		dev_err(dev, "Failed to end USB2 unknown calibration\n");
> >> +		return ret;
> >> +	}
> >> +
> >> +	/* Wait for PLL to be locked */
> >> +	ret = readl_poll_timeout(utmi->regs + USB2_PHY_PLL_CTRL_REG0, reg,
> >> +				 reg & PLL_READY,
> >> +				 PLL_LOCK_DELAY_US, PLL_LOCK_TIMEOUT_US);
> >> +	if (ret)
> >> +		dev_err(dev, "Failed to lock USB2 PLL\n");
> >> +
> >> +	return ret;
> >> +}
> >> +
> >> +static int mvebu_a3700_utmi_phy_power_off(struct phy *phy)
> >> +{
> >> +	struct mvebu_a3700_utmi *utmi = phy_get_drvdata(phy);
> >> +	int usb32 = utmi->caps->usb32;
> >> +	u32 reg;
> >> +
> >> +	if (!utmi)
> >> +		return -ENODEV;  
> 
> here too, utmi is referenced above.

Removed too.

> >> +
> >> +	/* Disable PHY pull-up and enable USB2 suspend */
> >> +	reg = readl(utmi->regs + USB2_PHY_CTRL(usb32));
> >> +	reg &= ~(RB_USB2PHY_PU | RB_USB2PHY_SUSPM(usb32));
> >> +	writel(reg, utmi->regs + USB2_PHY_CTRL(usb32));
> >> +
> >> +	/* Power down OTG module */
> >> +	if (usb32) {
> >> +		reg = readl(utmi->regs + USB2_PHY_OTG_CTRL);
> >> +		reg &= ~PHY_PU_OTG;
> >> +		writel(reg, utmi->regs + USB2_PHY_OTG_CTRL);
> >> +	}
> >> +
> >> +	return 0;
> >> +}
> >> +
> >> +static const struct phy_ops mvebu_a3700_utmi_phy_ops = {
> >> +	.power_on = mvebu_a3700_utmi_phy_power_on,
> >> +	.power_off = mvebu_a3700_utmi_phy_power_off,
> >> +	.owner = THIS_MODULE,
> >> +};
> >> +
> >> +static const struct mvebu_a3700_utmi_caps mvebu_a3700_utmi_otg_phy_caps = {
> >> +	.usb32 = true,
> >> +	.ops = &mvebu_a3700_utmi_phy_ops,
> >> +};
> >> +
> >> +static const struct mvebu_a3700_utmi_caps mvebu_a3700_utmi_host_phy_caps = {
> >> +	.usb32 = false,
> >> +	.ops = &mvebu_a3700_utmi_phy_ops,
> >> +};
> >> +
> >> +static const struct of_device_id mvebu_a3700_utmi_of_match[] = {
> >> +	{
> >> +		.compatible = "marvell,a3700-utmi-otg-phy",
> >> +		.data = &mvebu_a3700_utmi_otg_phy_caps,
> >> +	},
> >> +	{
> >> +		.compatible = "marvell,a3700-utmi-host-phy",
> >> +		.data = &mvebu_a3700_utmi_host_phy_caps,
> >> +	},
> >> +	{},
> >> +};
> >> +MODULE_DEVICE_TABLE(of, mvebu_a3700_utmi_of_match);
> >> +
> >> +static int mvebu_a3700_utmi_phy_probe(struct platform_device *pdev)
> >> +{
> >> +	const struct of_device_id *dev_id;
> >> +	struct device *dev = &pdev->dev;
> >> +	struct mvebu_a3700_utmi *utmi;
> >> +	struct phy_provider *provider;
> >> +	const struct phy_ops *ops;
> >> +	struct resource *res;
> >> +
> >> +	utmi = devm_kzalloc(dev, sizeof(*utmi), GFP_KERNEL);
> >> +	if (!utmi)
> >> +		return -ENOMEM;
> >> +
> >> +	/* Get UTMI memory region */
> >> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> >> +	if (!res) {
> >> +		dev_err(dev, "Missing UTMI PHY memory resource\n");
> >> +		return -ENODEV;
> >> +	}
> >> +
> >> +	utmi->regs = devm_ioremap_resource(dev, res);
> >> +	if (IS_ERR(utmi->regs))
> >> +		return PTR_ERR(utmi->regs);
> >> +
> >> +	/* Get miscellaneous Host/PHY region */
> >> +	utmi->usb_misc = syscon_regmap_lookup_by_phandle(dev->of_node,
> >> +							 "marvell,usb-misc-reg");
> >> +	if (IS_ERR(utmi->usb_misc)) {
> >> +		dev_err(dev,
> >> +			"Missing USB misc purpose system controller\n");
> >> +		return PTR_ERR(utmi->usb_misc);
> >> +	}
> >> +
> >> +	/* Retrieve PHY capabilities */
> >> +	dev_id = of_match_device(mvebu_a3700_utmi_of_match, dev);
> >> +	if (!dev_id)
> >> +		return -EINVAL;
> >> +
> >> +	utmi->caps = dev_id->data;  
> > a useful API to get @data: of_device_get_match_data()

Nice one, I forgot about it.

> >   
> >> +	ops = utmi->caps->ops;
> >> +
> >> +	/* Instantiate the PHY */
> >> +	utmi->phy = devm_phy_create(dev, NULL, ops);
> >> +	if (IS_ERR(utmi->phy)) {
> >> +		dev_err(dev, "Failed to create the UTMI PHY\n");
> >> +		return PTR_ERR(utmi->phy);
> >> +	}
> >> +
> >> +	phy_set_drvdata(utmi->phy, utmi);
> >> +
> >> +	/* Ensure the PHY is powered off */
> >> +	ops->power_off(utmi->phy);
> >> +
> >> +	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> >> +
> >> +	return PTR_ERR_OR_ZERO(provider);
> >> +}
> >> +
> >> +static int mvebu_a3700_utmi_phy_remove(struct platform_device *pdev)
> >> +{
> >> +	return 0;
> >> +}  
> 
> This empty remove function can be removed.

Sure.

> 
> Thanks
> Kishon
> 
> >> +
> >> +static struct platform_driver mvebu_a3700_utmi_driver = {
> >> +	.probe	= mvebu_a3700_utmi_phy_probe,
> >> +	.remove = mvebu_a3700_utmi_phy_remove,
> >> +	.driver	= {
> >> +		.name		= "mvebu-a3700-utmi-phy",
> >> +		.owner		= THIS_MODULE,
> >> +		.of_match_table	= mvebu_a3700_utmi_of_match,
> >> +	 },
> >> +};
> >> +module_platform_driver(mvebu_a3700_utmi_driver);
> >> +
> >> +MODULE_AUTHOR("Evan Wang <[email-masked]>");
> >> +MODULE_AUTHOR("Miquel Raynal <[email-masked]>");
> >> +MODULE_DESCRIPTION("Marvell EBU A3700 UTMI PHY driver");
> >> +MODULE_LICENSE("GPL");  
> > 
> >   

Thanks for reviewing!
Miquèl

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel