Re: [PATCH v2 06/11] phy: da8xx-usb: new driver for DA8XX SoC USB PHY

[Kishon Vijay Abraham I]

Hi,

On Thursday 17 March 2016 07:56 AM, David Lechner wrote:
> This is a new phy driver for the SoC USB controllers on the TI DA8XX
> family of microcontrollers. The USB 1.1 PHY is just a simple on/off.
> The USB 2.0 PHY also allows overriding the VBUS and ID pins.
> 
> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
> ---
> 
> v2 changes: This is new patch in v2.
> 
> 
> 
>  drivers/phy/Kconfig         |   9 ++
>  drivers/phy/Makefile        |   1 +
>  drivers/phy/phy-da8xx-usb.c | 295 ++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 305 insertions(+)
>  create mode 100644 drivers/phy/phy-da8xx-usb.c
> 
> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
> index 26566db..a6060ea 100644
> --- a/drivers/phy/Kconfig
> +++ b/drivers/phy/Kconfig
> @@ -35,6 +35,15 @@ config ARMADA375_USBCLUSTER_PHY
>  	depends on OF && HAS_IOMEM
>  	select GENERIC_PHY
>  
> +config PHY_DA8XX_USB
> +	tristate "TI DA8XX USB PHY Driver"
> +	depends on ARCH_DAVINCI_DA8XX
> +	select GENERIC_PHY
> +	help
> +	  Enable this to support the USB PHY on DA8XX SoCs.
> +
> +	  This driver controls both the USB 1.1 PHY and the USB 2.0 PHY.
> +
>  config PHY_DM816X_USB
>  	tristate "TI dm816x USB PHY driver"
>  	depends on ARCH_OMAP2PLUS
> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
> index 24596a9..722e01c 100644
> --- a/drivers/phy/Makefile
> +++ b/drivers/phy/Makefile
> @@ -5,6 +5,7 @@
>  obj-$(CONFIG_GENERIC_PHY)		+= phy-core.o
>  obj-$(CONFIG_PHY_BERLIN_USB)		+= phy-berlin-usb.o
>  obj-$(CONFIG_PHY_BERLIN_SATA)		+= phy-berlin-sata.o
> +obj-$(CONFIG_PHY_DA8XX_USB)		+= phy-da8xx-usb.o
>  obj-$(CONFIG_PHY_DM816X_USB)		+= phy-dm816x-usb.o
>  obj-$(CONFIG_ARMADA375_USBCLUSTER_PHY)	+= phy-armada375-usb2.o
>  obj-$(CONFIG_BCM_KONA_USB2_PHY)		+= phy-bcm-kona-usb2.o
> diff --git a/drivers/phy/phy-da8xx-usb.c b/drivers/phy/phy-da8xx-usb.c
> new file mode 100644
> index 0000000..93a5f4d
> --- /dev/null
> +++ b/drivers/phy/phy-da8xx-usb.c
> @@ -0,0 +1,295 @@
> +/*
> + * phy-da8xx-usb - TI DaVinci DA8XX USB PHY driver
> + *
> + * Copyright (C) 2016 David Lechner <david@xxxxxxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
> +#include <linux/module.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/usb/gadget.h>
> +#include <linux/usb/musb.h>
> +#include <linux/usb/otg.h>
> +
> +/* DA8xx CFGCHIP2 (USB PHY Control) register bits */
> +#define PHYCLKGD		(1 << 17)
> +#define VBUSSENSE		(1 << 16)
> +#define RESET			(1 << 15)
> +#define OTGMODE_MASK		(3 << 13)
> +#define NO_OVERRIDE		(0 << 13)
> +#define FORCE_HOST		(1 << 13)
> +#define FORCE_DEVICE		(2 << 13)
> +#define FORCE_HOST_VBUS_LOW	(3 << 13)
> +#define USB1PHYCLKMUX		(1 << 12)
> +#define USB2PHYCLKMUX		(1 << 11)
> +#define PHYPWRDN		(1 << 10)
> +#define OTGPWRDN		(1 << 9)
> +#define DATPOL			(1 << 8)
> +#define USB1SUSPENDM		(1 << 7)
> +#define PHY_PLLON		(1 << 6)
> +#define SESENDEN		(1 << 5)
> +#define VBDTCTEN		(1 << 4)
> +#define REFFREQ_MASK		(0xf << 0)
> +#define REFFREQ_12MHZ		(1 << 0)
> +#define REFFREQ_24MHZ		(2 << 0)
> +#define REFFREQ_48MHZ		(3 << 0)
> +#define REFFREQ_19_2MHZ		(4 << 0)
> +#define REFFREQ_38_4MHZ		(5 << 0)
> +#define REFFREQ_13MHZ		(6 << 0)
> +#define REFFREQ_26MHZ		(7 << 0)
> +#define REFFREQ_20MHZ		(8 << 0)
> +#define REFFREQ_40MHZ		(9 << 0)
> +
> +struct da8xx_usbphy {
> +	struct phy_provider	*phy_provider;
> +	struct phy		*usb11_phy;
> +	struct phy		*usb20_phy;
> +	struct clk		*usb11_clk;
> +	struct clk		*usb20_clk;
> +	void __iomem		*phy_ctrl;
> +};
> +
> +static inline u32 da8xx_usbphy_readl(void __iomem *base)
> +{
> +	return readl(base);
> +}
> +
> +static inline void da8xx_usbphy_writel(void __iomem *base, u32 value)
> +{
> +	writel(value, base);
> +}
> +
> +static int da8xx_usb11_phy_init(struct phy *phy)
> +{
> +	struct da8xx_usbphy *d_phy = phy_get_drvdata(phy);
> +	int ret;
> +	u32 val;
> +
> +	ret = clk_prepare_enable(d_phy->usb11_clk);
> +	if (ret)
> +		return ret;
> +
> +	val = da8xx_usbphy_readl(d_phy->phy_ctrl);
> +	val |= USB1SUSPENDM;
> +	da8xx_usbphy_writel(d_phy->phy_ctrl, val);
> +
> +	return 0;
> +}
> +
> +static int da8xx_usb11_phy_shutdown(struct phy *phy)
> +{
> +	struct da8xx_usbphy *d_phy = phy_get_drvdata(phy);
> +	u32 val;
> +
> +	val = da8xx_usbphy_readl(d_phy->phy_ctrl);
> +	val &= ~USB1SUSPENDM;
> +	da8xx_usbphy_writel(d_phy->phy_ctrl, val);
> +
> +	clk_disable_unprepare(d_phy->usb11_clk);
> +
> +	return 0;
> +}
> +
> +static const struct phy_ops da8xx_usb11_phy_ops = {
> +	.power_on	= da8xx_usb11_phy_init,
> +	.power_off	= da8xx_usb11_phy_shutdown,
> +	.owner		= THIS_MODULE,
> +};
> +
> +static int da8xx_usb20_phy_init(struct phy *phy)
> +{
> +	struct da8xx_usbphy *d_phy = phy_get_drvdata(phy);
> +	int ret;
> +	u32 val;
> +
> +	ret = clk_prepare_enable(d_phy->usb20_clk);
> +	if (ret)
> +		return ret;
> +
> +	val = da8xx_usbphy_readl(d_phy->phy_ctrl);
> +	val &= ~OTGPWRDN;
> +	da8xx_usbphy_writel(d_phy->phy_ctrl, val);
> +
> +	return 0;
> +}
> +
> +static int da8xx_usb20_phy_shutdown(struct phy *phy)
> +{
> +	struct da8xx_usbphy *d_phy = phy_get_drvdata(phy);
> +	u32 val;
> +
> +	val = da8xx_usbphy_readl(d_phy->phy_ctrl);
> +	val |= OTGPWRDN;
> +	da8xx_usbphy_writel(d_phy->phy_ctrl, val);
> +
> +	clk_disable_unprepare(d_phy->usb20_clk);
> +
> +	return 0;
> +}
> +
> +static const struct phy_ops da8xx_usb20_phy_ops = {
> +	.power_on	= da8xx_usb20_phy_init,
> +	.power_off	= da8xx_usb20_phy_shutdown,
> +	.owner		= THIS_MODULE,
> +};
> +
> +int da8xx_usb20_phy_set_mode(struct phy *phy, enum musb_mode mode)
> +{
> +	struct da8xx_usbphy *d_phy = phy_get_drvdata(phy);
> +	u32 val;
> +
> +	val = da8xx_usbphy_readl(d_phy->phy_ctrl);
> +
> +	val &= ~OTGMODE_MASK;
> +	switch (mode) {
> +	case MUSB_HOST:		/* Force VBUS valid, ID = 0 */
> +		val |= FORCE_HOST;
> +		break;
> +	case MUSB_PERIPHERAL:	/* Force VBUS valid, ID = 1 */
> +		val |= FORCE_DEVICE;
> +		break;
> +	case MUSB_OTG:		/* Don't override the VBUS/ID comparators */
> +		val |= NO_OVERRIDE;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	da8xx_usbphy_writel(d_phy->phy_ctrl, val);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(da8xx_usb20_phy_set_mode);

Don't prefer export symbols from PHY driver. That'll create unnecessary
dependencies between the controller and the PHY.

I think it'll be better to create a new attribute and use it?

8<============

diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index 8cf05e3..3d92b9b 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -22,6 +22,13 @@

 struct phy;

+enum phy_mode {
+	PHY_MODE_INVALID,
+	PHY_MODE_USB_HOST,
+	PHY_MODE_USB_DEVICE,
+	PHY_MODE_USB_OTG,
+};
+
 /**
  * struct phy_ops - set of function pointers for performing phy operations
  * @init: operation to be performed for initializing phy
@@ -44,6 +51,7 @@ struct phy_ops {
  */
 struct phy_attrs {
 	u32			bus_width;
+	enum phy_mode		mode;
 };

 /**
@@ -127,6 +135,14 @@ static inline void phy_set_bus_width(struct phy *phy, int
bus_width)
 {
 	phy->attrs.bus_width = bus_width;
 }
+static inline enum phy_mode phy_get_mode(struct phy *phy)
+{
+	return phy->attrs.mode;
+}
+static inline void phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	phy->attrs.mode = mode;
+}
 struct phy *phy_get(struct device *dev, const char *string);
 struct phy *phy_optional_get(struct device *dev, const char *string);
 struct phy *devm_phy_get(struct device *dev, const char *string);
@@ -234,6 +250,16 @@ static inline void phy_set_bus_width(struct phy *phy, int
bus_width)
 	return;
 }

+static inline enum phy_mode phy_get_mode(struct phy *phy)
+{
+	return PHY_MODE_INVALID;
+}
+
+static inline void phy_set_mode(struct phy *phy, enum phy_mode mode)
+{
+	return;
+}
+
 static inline struct phy *phy_get(struct device *dev, const char *string)
 {
 	return ERR_PTR(-ENOSYS);


=====================>8

Thanks
Kishon

> +
> +static struct phy *da8xx_usbphy_of_xlate(struct device *dev,
> +					 struct of_phandle_args *args)
> +{
> +	struct da8xx_usbphy *d_phy = dev_get_drvdata(dev);
> +
> +	if (!d_phy)
> +		return ERR_PTR(-ENODEV);
> +
> +	switch (args->args[0]) {
> +	case 1:
> +		return d_phy->usb11_phy;
> +	case 2:
> +		return d_phy->usb20_phy;
> +	default:
> +		return ERR_PTR(-EINVAL);
> +	}
> +}
> +
> +static int da8xx_usbphy_probe(struct platform_device *pdev)
> +{
> +	struct device		*dev = &pdev->dev;
> +	struct device_node	*node = dev->of_node;
> +	struct da8xx_usbphy	*d_phy;
> +	struct resource		*res;
> +
> +	d_phy = devm_kzalloc(dev, sizeof(*d_phy), GFP_KERNEL);
> +	if (!d_phy)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	d_phy->phy_ctrl = devm_ioremap_resource(dev, res);
> +	if (IS_ERR(d_phy->phy_ctrl)) {
> +		dev_err(dev, "Failed to map resource.\n");
> +		return PTR_ERR(d_phy->phy_ctrl);
> +	}
> +
> +	d_phy->usb11_clk = devm_clk_get(dev, "usb11_phy");
> +	if (IS_ERR(d_phy->usb11_clk)) {
> +		dev_err(dev, "Failed to get usb11_phy clock.\n");
> +		return PTR_ERR(d_phy->usb11_clk);
> +	}
> +
> +	d_phy->usb20_clk = devm_clk_get(dev, "usb20_phy");
> +	if (IS_ERR(d_phy->usb20_clk)) {
> +		dev_err(dev, "Failed to get usb20_phy clock.\n");
> +		return PTR_ERR(d_phy->usb20_clk);
> +	}
> +
> +	d_phy->usb11_phy = devm_phy_create(dev, node, &da8xx_usb11_phy_ops);
> +	if (IS_ERR(d_phy->usb11_phy)) {
> +		dev_err(dev, "Failed to create usb11 phy.\n");
> +		return PTR_ERR(d_phy->usb11_phy);
> +	}
> +
> +	d_phy->usb20_phy = devm_phy_create(dev, node, &da8xx_usb20_phy_ops);
> +	if (IS_ERR(d_phy->usb20_phy)) {
> +		dev_err(dev, "Failed to create usb20 phy.\n");
> +		return PTR_ERR(d_phy->usb20_phy);
> +	}
> +
> +	platform_set_drvdata(pdev, d_phy);
> +	phy_set_drvdata(d_phy->usb11_phy, d_phy);
> +	phy_set_drvdata(d_phy->usb20_phy, d_phy);
> +
> +	if (node) {
> +		d_phy->phy_provider = devm_of_phy_provider_register(dev,
> +							da8xx_usbphy_of_xlate);
> +		if (IS_ERR(d_phy->phy_provider)) {
> +			dev_err(dev, "Failed to create phy provider.\n");
> +			return PTR_ERR(d_phy->phy_provider);
> +		}
> +	} else {
> +		int ret;
> +
> +		ret = phy_create_lookup(d_phy->usb11_phy, "usbphy", "ohci.0");
> +		if (ret)
> +			dev_warn(dev, "Failed to create usb11 phy lookup .\n");
> +		ret = phy_create_lookup(d_phy->usb20_phy, "usbphy", "musb-da8xx");
> +		if (ret)
> +			dev_warn(dev, "Failed to create usb20 phy lookup .\n");
> +	}
> +
> +	return 0;
> +}
> +
> +static int da8xx_usbphy_remove(struct platform_device *pdev)
> +{
> +	struct da8xx_usbphy *d_phy = platform_get_drvdata(pdev);
> +
> +	if (!pdev->dev.of_node) {
> +		phy_remove_lookup(d_phy->usb20_phy, "usbphy", "musb-da8xx");
> +		phy_remove_lookup(d_phy->usb11_phy, "usbphy", "ohci.0");
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id da8xx_usbphy_ids[] = {
> +	{ .compatible = "ti,da830-usbphy" },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(of, da8xx_usbphy_ids);
> +
> +static struct platform_driver da8xx_usbphy_driver = {
> +	.probe	= da8xx_usbphy_probe,
> +	.remove	= da8xx_usbphy_remove,
> +	.driver	= {
> +		.name	= "da8xx-usbphy",
> +		.of_match_table = da8xx_usbphy_ids,
> +	},
> +};
> +
> +module_platform_driver(da8xx_usbphy_driver);
> +
> +MODULE_ALIAS("platform:da8xx-usbphy");
> +MODULE_AUTHOR("David Lechner <david@xxxxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("TI DA8XX USB PHY driver");
> +MODULE_LICENSE("GPL v2");
>