Subject: [PATCH] ARM: sunxi: Add driver for sunxi usb phy

From: [email-masked] (Hans de Goede)
Date: Fri, 07 Feb 2014 16:57:47 +0100

Hi,

On 01/15/2014 04:00 PM, Kishon Vijay Abraham I wrote:
> On Wednesday 15 January 2014 04:28 AM, Hans de Goede wrote:
>> The Allwinner A1x / A2x SoCs have 2 or 3 usb phys which are all accessed
>> through a single set of registers. Besides this there are also some other
>> phy related bits which need poking, which are per phy, but shared between the
>> ohci and ehci controllers, so these are also controlled from this new phy
>> driver.
>>
>> Signed-off-by: Hans de Goede <[email-masked]>
>> ---
>>   .../devicetree/bindings/phy/sun4i-usb-phy.txt      |  26 ++
>>   drivers/phy/Kconfig                                |  11 +
>>   drivers/phy/Makefile                               |   1 +
>>   drivers/phy/phy-sun4i-usb.c                        | 318 +++++++++++++++++++++
>>   4 files changed, 356 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/phy/sun4i-usb-phy.txt
>>   create mode 100644 drivers/phy/phy-sun4i-usb.c
>>
>> diff --git a/Documentation/devicetree/bindings/phy/sun4i-usb-phy.txt b/Documentation/devicetree/bindings/phy/sun4i-usb-phy.txt
>> new file mode 100644
>> index 0000000..6c54b3b
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/phy/sun4i-usb-phy.txt
>> @@ -0,0 +1,26 @@
>> +Allwinner sun4i USB PHY
>> +-----------------------
>> +
>> +Required properties:
>> +- compatible : should be one of "allwinner,sun4i-a10-usb-phy",
>> +  "allwinner,sun5i-a13-usb-phy" or "allwinner,sun7i-a20-usb-phy"
>> +- reg : 2 or 3 register offset + length pairs, 1 phy base reg pair +
>> +  1 pair for the pmu-irq register of each hcd
>> +- #phy-cells : from the generic phy bindings, must be 1
>> +
>> +Optional properties:
>> +- clocks : phandle + clock specifier for the phy clock
>> +- clock-names : "usb_phy"
>> +- resets : a list of phandle + reset specifier pairs
>> +- reset-names : "usb0_reset", "usb1_reset", and / or "usb2_reset"
>> +
>> +Example:
>> +	usbphy: phy at 0x01c13400 {
>> +		#phy-cells = <1>;
>> +		compatible = "allwinner,sun4i-a10-usb-phy";
>> +		reg = <0x01c13400 0x10 0x01c14800 0x4 0x01c1c800 0x4>;
>> +		clocks = <&usb_clk 8>;
>> +		clock-names = "usb_phy";
>> +		resets = <&usb_clk 1>, <&usb_clk 2>;
>> +		reset-names = "usb1_reset", "usb2_reset";
>> +	};
>> diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
>> index 330ef2d..dcce4cf 100644
>> --- a/drivers/phy/Kconfig
>> +++ b/drivers/phy/Kconfig
>> @@ -51,4 +51,15 @@ config PHY_EXYNOS_DP_VIDEO
>>   	help
>>   	  Support for Display Port PHY found on Samsung EXYNOS SoCs.
>>
>> +config PHY_SUN4I_USB
>> +	tristate "Allwinner sunxi SoC USB PHY driver"
>> +	depends on ARCH_SUNXI
>> +	select GENERIC_PHY
>> +	help
>> +	  Enable this to support the transceiver that is part of Allwinner
>> +	  sunxi SoCs.
>> +
>> +	  This driver controls the entire USB PHY block, both the USB OTG
>> +	  parts, as well as the 2 regular USB 2 host PHYs.
>> +
>>   endmenu
>> diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
>> index d0caae9..e9e82f0 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_SUN4I_USB)		+= phy-sun4i-usb.o
>> diff --git a/drivers/phy/phy-sun4i-usb.c b/drivers/phy/phy-sun4i-usb.c
>> new file mode 100644
>> index 0000000..a15ecc1
>> --- /dev/null
>> +++ b/drivers/phy/phy-sun4i-usb.c
>> @@ -0,0 +1,318 @@
>> +/*
>> + * Allwinner sun4i USB phy driver
>> + *
>> + * Copyright (C) 2014 Hans de Goede <[email-masked]>
>> + *
>> + * Based on code from
>> + * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
>> + *
>> + * Modelled after: Samsung S5P/EXYNOS SoC series MIPI CSIS/DSIM DPHY driver
>> + * Copyright (C) 2013 Samsung Electronics Co., Ltd.
>> + * Author: Sylwester Nawrocki <[email-masked]>
>> + *
>> + * 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/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/mutex.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/phy/phy.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/reset.h>
>> +
>> +#define REG_ISCR			0x00
>> +#define REG_PHYCTL			0x04
>> +#define REG_PHYBIST			0x08
>> +#define REG_PHYTUNE			0x0c
>> +
>> +#define SUNXI_AHB_ICHR8_EN		BIT(10)
>> +#define SUNXI_AHB_INCR4_BURST_EN	BIT(9)
>> +#define SUNXI_AHB_INCRX_ALIGN_EN	BIT(8)
>> +#define SUNXI_ULPI_BYPASS_EN		BIT(0)
>> +
>> +#define MAX_PHYS			3
>> +
>> +struct sun4i_usb_phy_data {
>> +	struct clk *clk;
>> +	void __iomem *base;
>> +	struct mutex mutex;
>> +	int num_phys;
>> +	u32 disc_thresh;
>> +	struct sun4i_usb_phy {
>> +		struct phy *phy;
>> +		void __iomem *pmu_irq;
>
> 'pmu_irq' is misleading. Can you think of a better name?

Changed this to pmu in my local tree, I'll send a v2 after some testing.

>
> Btw Kamil uses syscon interface to set pmu bits. Is it applicable here also?

The syscon interface is useful only for shared registers, this register is only
used by the phy driver, so I see no value in using the syscon interface.

>> +		struct regulator *vbus;
>> +		struct reset_control *reset;
>> +		int index;
>> +	} phys[MAX_PHYS];
>> +};
>> +
>> +#define to_sun4i_usb_phy_data(phy) \
>> +	container_of((phy), struct sun4i_usb_phy_data, phys[(phy)->index])
>> +
>> +static void sun4i_usb_phy_write(struct sun4i_usb_phy *phy, u32 addr, u32 data,
>> +				int len)
>> +{
>> +	struct sun4i_usb_phy_data *phy_data = to_sun4i_usb_phy_data(phy);
>> +	u32 temp, usbc_bit = BIT(phy->index * 2);
>> +	int i;
>> +
>> +	mutex_lock(&phy_data->mutex);
>> +
>> +	for (i = 0; i < len; i++) {
>> +		temp = readl(phy_data->base + REG_PHYCTL);
>> +
>> +		/* clear the address portion */
>> +		temp &= ~(0xff << 8);
>> +
>> +		/* set the address */
>> +		temp |= ((addr + i) << 8);
>> +		writel(temp, phy_data->base + REG_PHYCTL);
>> +
>> +		/* set the data bit and clear usbc bit*/
>> +		temp = readb(phy_data->base + REG_PHYCTL);
>> +		if (data & 0x1)
>> +			temp |= BIT(7);
>> +		else
>> +			temp &= ~BIT(7);
>> +		temp &= ~usbc_bit;
>> +		writeb(temp, phy_data->base + REG_PHYCTL);
>> +
>> +		/* pulse usbc_bit */
>> +		temp = readb(phy_data->base + REG_PHYCTL);
>> +		temp |= usbc_bit;
>> +		writeb(temp, phy_data->base + REG_PHYCTL);
>> +
>> +		temp = readb(phy_data->base + REG_PHYCTL);
>> +		temp &= ~usbc_bit;
>> +		writeb(temp, phy_data->base + REG_PHYCTL);
>> +
>> +		data >>= 1;
>> +	}
>> +	mutex_unlock(&phy_data->mutex);
>> +}
>> +
>> +static void sun4i_usb_phy_passby(struct sun4i_usb_phy *phy, int enable)
>> +{
>> +	u32 bits, reg_value;
>> +
>> +	if (!phy->pmu_irq)
>> +		return;
>> +
>> +	bits = SUNXI_AHB_ICHR8_EN | SUNXI_AHB_INCR4_BURST_EN |
>> +		SUNXI_AHB_INCRX_ALIGN_EN | SUNXI_ULPI_BYPASS_EN;
>> +
>> +	reg_value = readl(phy->pmu_irq);
>> +
>> +	if (enable)
>> +		reg_value |= bits;
>> +	else
>> +		reg_value &= ~bits;
>> +
>> +	writel(reg_value, phy->pmu_irq);
>> +}
>> +
>> +static int sun4i_usb_phy_init(struct phy *_phy)
>> +{
>> +	struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
>> +	struct sun4i_usb_phy_data *data = to_sun4i_usb_phy_data(phy);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(data->clk);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = reset_control_deassert(phy->reset);
>> +	if (ret) {
>> +		clk_disable_unprepare(data->clk);
>> +		return ret;
>> +	}
>> +
>> +	/* Adjust PHY's magnitude and rate */
>> +	sun4i_usb_phy_write(phy, 0x20, 0x14, 5);
>
> No magic values. Use macros instead.

Fixed for the addresses, the 0x14 will stay magic though, as we've no
idea what it actually does.

>> +
>> +	/* Disconnect threshold adjustment */
>> +	sun4i_usb_phy_write(phy, 0x2a, data->disc_thresh, 2);
>> +
>> +	sun4i_usb_phy_passby(phy, 1);
>> +
>> +	return 0;
>> +}
>> +
>> +static int sun4i_usb_phy_exit(struct phy *_phy)
>> +{
>> +	struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
>> +	struct sun4i_usb_phy_data *data = to_sun4i_usb_phy_data(phy);
>> +
>> +	sun4i_usb_phy_passby(phy, 0);
>> +	reset_control_assert(phy->reset);
>> +	clk_disable_unprepare(data->clk);
>
> Actually PHY API's can be called in interrupt context, in that case
> clk_disable_unprepare can't be used.
>> +
>> +	return 0;
>> +}
>> +
>> +static int sun4i_usb_phy_power_on(struct phy *_phy)
>> +{
>> +	struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
>> +	int ret;
>> +
>> +	if (phy->vbus) {
>> +		ret = regulator_enable(phy->vbus);
>> +		if (ret)
>> +			return ret;
>> +
>> +	}
>> +
>> +	return 0;
>> +}
>
> This can simply be
> int ret = 0;
> if (phy->vbus)
> 	ret = regulator_enable(phy->vbus);
> return ret;

Fixed.

>> +
>> +static int sun4i_usb_phy_power_off(struct phy *_phy)
>> +{
>> +	struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
>> +
>> +	if (phy->vbus)
>> +		regulator_disable(phy->vbus);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct phy_ops sun4i_usb_phy_ops = {
>> +	.init		= sun4i_usb_phy_init,
>> +	.exit		= sun4i_usb_phy_exit,
>> +	.power_on	= sun4i_usb_phy_power_on,
>> +	.power_off	= sun4i_usb_phy_power_off,
>> +	.owner		= THIS_MODULE,
>> +};
>> +
>> +static struct phy *sun4i_usb_phy_xlate(struct device *dev,
>> +					struct of_phandle_args *args)
>> +{
>> +	struct sun4i_usb_phy_data *data = dev_get_drvdata(dev);
>> +
>> +	if (WARN_ON(args->args[0] == 0 || args->args[0] >= data->num_phys))
>> +		return ERR_PTR(-ENODEV);
>> +
>> +	return data->phys[args->args[0]].phy;
>> +}
>> +
>> +static int sun4i_usb_phy_probe(struct platform_device *pdev)
>> +{
>> +	struct sun4i_usb_phy_data *data;
>> +	struct device *dev = &pdev->dev;
>> +	struct device_node *np = dev->of_node;
>> +	void __iomem *pmu_irq = NULL;
>> +	struct phy_provider *phy_provider;
>> +	struct reset_control *reset;
>> +	struct regulator *vbus;
>> +	struct phy *phy;
>> +	char name[16];
>> +	int i;
>> +
>> +	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
>> +	if (!data)
>> +		return -ENOMEM;
>> +
>> +	mutex_init(&data->mutex);
>> +	if (of_device_is_compatible(np, "allwinner,sun4i-a10-usb-phy")) {
>> +		data->num_phys = 3;
>> +		data->disc_thresh = 3;
>> +	} else if (of_device_is_compatible(np,
>> +					"allwinner,sun5i-a13-usb-phy")) {
>> +		data->num_phys = 2;
>> +		data->disc_thresh = 2;
>> +	} else { /* allwinner,sun7i-a20-usb-phy */
>> +		data->num_phys = 3;
>> +		data->disc_thresh = 2;
>> +	}
>> +
>> +	data->clk = devm_clk_get(dev, "usb_phy");
>> +	if (IS_ERR(data->clk)) {
>> +		dev_err(dev, "could not get usb_phy clock\n");
>> +		return PTR_ERR(data->clk);
>> +	}
>> +
>> +	/* Skip 0, 0 is the phy for otg which is not yet supported. */
>> +	for (i = 1; i < data->num_phys; i++) {
>> +		snprintf(name, sizeof(name), "usb%d_vbus", i);
>> +		vbus = devm_regulator_get_optional(dev, name);
>> +		if (IS_ERR(vbus)) {
>> +			if (PTR_ERR(vbus) == -EPROBE_DEFER)
>> +				return -EPROBE_DEFER;
>> +			vbus = NULL;
>> +		}
>> +
>> +		snprintf(name, sizeof(name), "usb%d_reset", i);
>> +		reset = devm_reset_control_get(dev, name);
>> +		if (IS_ERR(phy)) {
>> +			dev_err(dev, "failed to get reset %s\n", name);
>> +			return PTR_ERR(phy);
>> +		}
>> +
>> +		if (i) { /* No pmu_irq for usbc0 */
>> +			pmu_irq = devm_ioremap_resource(dev,
>> +			      platform_get_resource(pdev, IORESOURCE_MEM, i));
>> +			if (IS_ERR(pmu_irq))
>> +				return PTR_ERR(pmu_irq);
>> +		}
>> +
>> +		phy = devm_phy_create(dev, &sun4i_usb_phy_ops, NULL);
>> +		if (IS_ERR(phy)) {
>> +			dev_err(dev, "failed to create PHY %d\n", i);
>> +			return PTR_ERR(phy);
>> +		}
>> +
>> +		data->phys[i].phy = phy;
>> +		data->phys[i].pmu_irq = pmu_irq;
>> +		data->phys[i].vbus = vbus;
>> +		data->phys[i].reset = reset;
>> +		data->phys[i].index = i;
>> +		phy_set_drvdata(phy, &data->phys[i]);
>> +	}
>> +
>> +	data->base = devm_ioremap_resource(dev,
>> +			platform_get_resource(pdev, IORESOURCE_MEM, 0));
>> +	if (IS_ERR(data->base))
>> +		return PTR_ERR(data->base);
>> +
>> +	dev_set_drvdata(dev, data);
>> +	phy_provider = devm_of_phy_provider_register(dev, sun4i_usb_phy_xlate);
>> +	if (IS_ERR(phy_provider))
>> +		return PTR_ERR(phy_provider);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id sun4i_usb_phy_of_match[] = {
>> +	{ .compatible = "allwinner,sun4i-a10-usb-phy" },
>> +	{ .compatible = "allwinner,sun5i-a13-usb-phy" },
>> +	{ .compatible = "allwinner,sun7i-a20-usb-phy" },
>> +	{ },
>> +};
>> +MODULE_DEVICE_TABLE(of, sun4i_usb_phy_of_match);
>> +
>> +static struct platform_driver sun4i_usb_phy_driver = {
>> +	.probe	= sun4i_usb_phy_probe,
>> +	.driver = {
>> +		.of_match_table	= sun4i_usb_phy_of_match,
>> +		.name  = "sun4i-usb-phy",
>> +		.owner = THIS_MODULE,
>> +	}
>> +};
>> +module_platform_driver(sun4i_usb_phy_driver);
>> +
>> +MODULE_DESCRIPTION("Allwinner sun4i USB phy driver");
>> +MODULE_AUTHOR("Hans de Goede <[email-masked]>");
>> +MODULE_LICENSE("GPL");
>
> GPL v2?

Fixed.

> This patch looks good apart from those minor comments.

Ok v2 is on its way.

Regards,

Hans