[PATCH] ARM: sunxi: Add driver for sunxi usb phy
Kishon Vijay Abraham I
kishon at ti.com
Thu Jan 16 00:17:06 EST 2014
Hi,
On Wednesday 15 January 2014 09:18 PM, Hans de Goede wrote:
> 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 <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?
>
> The pmu_irq name comes from android sources, but I agree it is no good,
> how about just pmu ?
yeah.
>
>> Btw Kamil uses syscon interface to set pmu bits. Is it applicable here also?
>
> Both Kamil and syscon are now to me, do you have a pointer to example sources
> for this?
Maybe have a look at Kamil's patches [1]?
[1] -> https://lkml.org/lkml/2013/12/20/216
>
>>> + 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.
>
> We don't have docs, these values come from the Android code (and the comment
> above has been translated from Chinese). I can make up some random
> macros for this, but seems counter-productive, it seems best to just leave
> this as magic until the day we actually have documentation and thus can use
> defines with the proper register names, etc.
Al-right.
>
>>> +
>>> + /* 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.
>
> Erm, phy_init and phy_exit from drivers/phy/phy-core.c use mutex_lock,
> so they can never be called from interrupt context.
damn.. sorry :-s
>
>>> +
>>> + 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;
>
> Agreed, will fix as soon as its clear what to do with the other bits.
>
>>> +
>>> +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?
>
> It is GPL v2 or later, and using just "GPL" is the norm indeed
> lately I've seen some driver use "GPL xxxxx" but the vast majority
> of the drivers in the kernel has just "GPL".
The header of this file states 'either version 2 of the License, or
(at your option) any later version', so it's better to add GPL v2.
>
> Thanks for the review!
>
> Regards,
>
> Hans
>
>
> p.s.
>
> A question about my 2 phy-core patches, as well as this one once the
> review comments are addressed. How do I get phy patches upstream, will
> you take care of this, or should I send them somewhere else ?
Yeah, I'll pick them up once -rc1 is tagged.
Cheers
Kishon
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