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

Kishon Vijay Abraham I kishon at ti.com
Wed Jan 15 10:00:10 EST 2014


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 <hdegoede at redhat.com>
> ---
>  .../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 <hdegoede at redhat.com>
> + *
> + * 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 <s.nawrocki at samsung.com>
> + *
> + * 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?

Btw Kamil uses syscon interface to set pmu bits. Is it applicable here also?
> +		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.
> +
> +	/* 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;
> +
> +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 <hdegoede at redhat.com>");
> +MODULE_LICENSE("GPL");

GPL v2?

This patch looks good apart from those minor comments.

Cheers
Kishon



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