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Message-ID: <1f1497f9-b331-3fc6-d820-3089eb637f18@starfivetech.com>
Date:   Mon, 24 Apr 2023 18:59:22 +0800
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Subject: Re: [PATCH v5 3/7] phy: starfive: Add JH7110 USB 2.0 PHY driver
Content-Language: en-US
To:     Roger Quadros <rogerq@kernel.org>,
        Emil Renner Berthing <emil.renner.berthing@canonical.com>,
        Conor Dooley <conor@kernel.org>,
        "Vinod Koul" <vkoul@kernel.org>,
        Kishon Vijay Abraham I <kishon@kernel.org>,
        "Rob Herring" <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Pawel Laszczak <pawell@cadence.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Peter Chen <peter.chen@kernel.org>,
        Philipp Zabel <p.zabel@pengutronix.de>
CC:     <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <linux-phy@lists.infradead.org>, <linux-usb@vger.kernel.org>,
        <linux-riscv@lists.infradead.org>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        "Mason Huo" <mason.huo@starfivetech.com>
References: <20230420110052.3182-1-minda.chen@starfivetech.com>
 <20230420110052.3182-4-minda.chen@starfivetech.com>
 <f9666a06-8087-f804-202a-dbb744011d3a@kernel.org>
From:   Minda Chen <minda.chen@starfivetech.com>
In-Reply-To: <f9666a06-8087-f804-202a-dbb744011d3a@kernel.org>
Content-Type: text/plain; charset="UTF-8"
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Precedence: bulk


On 2023/4/24 16:46, Roger Quadros wrote:
> Hi Minda,
> 
> On 20/04/2023 14:00, Minda Chen wrote:
>> Add Starfive JH7110 SoC USB 2.0 PHY driver support.
>> USB 2.0 PHY default connect to Cadence USB controller.
>> 
>> Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
>> ---
>>  MAINTAINERS                           |   6 +
>>  drivers/phy/starfive/Kconfig          |  11 ++
>>  drivers/phy/starfive/Makefile         |   1 +
>>  drivers/phy/starfive/phy-jh7110-usb.c | 162 ++++++++++++++++++++++++++
>>  4 files changed, 180 insertions(+)
>>  create mode 100644 drivers/phy/starfive/phy-jh7110-usb.c
>> 
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 1aef5ba46d71..c09ea66dcd5a 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -19968,6 +19968,12 @@ M:	William Qiu <william.qiu@starfivetech.com>
>>  S:	Supported
>>  F:	Documentation/devicetree/bindings/soc/starfive/starfive,jh7110-syscon.yaml
>>  
>> +STARFIVE JH71X0 USB PHY DRIVER
>> +M:	Minda Chen <minda.chen@starfivetech.com>
>> +S:	Supported
>> +F:	Documentation/devicetree/bindings/phy/starfive,jh7110-usb-phy.yaml
>> +F:	drivers/phy/starfive/phy-jh7110-usb.c
>> +
>>  STATIC BRANCH/CALL
>>  M:	Peter Zijlstra <peterz@infradead.org>
>>  M:	Josh Poimboeuf <jpoimboe@kernel.org>
>> diff --git a/drivers/phy/starfive/Kconfig b/drivers/phy/starfive/Kconfig
>> index f989b8ff8bcb..2c013c390dee 100644
>> --- a/drivers/phy/starfive/Kconfig
>> +++ b/drivers/phy/starfive/Kconfig
>> @@ -11,3 +11,14 @@ config PHY_STARFIVE_DPHY_RX
>>  	  Choose this option if you have a StarFive D-PHY in your
>>  	  system. If M is selected, the module will be called
>>  	  phy-starfive-dphy-rx.
>> +
>> +config PHY_STARFIVE_JH7110_USB
>> +	tristate "Starfive JH7110 USB 2.0 PHY support"
>> +	depends on USB_SUPPORT
>> +	select GENERIC_PHY
>> +	select USB_PHY
>> +	help
>> +	  Enable this to support the StarFive USB 2.0 PHY,
>> +	  used with the Cadence USB controller.
>> +	  If M is selected, the module will be called
>> +	  phy-jh7110-usb.ko.
>> diff --git a/drivers/phy/starfive/Makefile b/drivers/phy/starfive/Makefile
>> index 7ec576cb30ae..176443852f4d 100644
>> --- a/drivers/phy/starfive/Makefile
>> +++ b/drivers/phy/starfive/Makefile
>> @@ -1,2 +1,3 @@
>>  # SPDX-License-Identifier: GPL-2.0
>>  obj-$(CONFIG_PHY_STARFIVE_DPHY_RX)      += phy-starfive-dphy-rx.o
>> +obj-$(CONFIG_PHY_STARFIVE_JH7110_USB)	+= phy-jh7110-usb.o
>> diff --git a/drivers/phy/starfive/phy-jh7110-usb.c b/drivers/phy/starfive/phy-jh7110-usb.c
>> new file mode 100644
>> index 000000000000..4a12df0692cd
>> --- /dev/null
>> +++ b/drivers/phy/starfive/phy-jh7110-usb.c
>> @@ -0,0 +1,162 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +/*
>> + * StarFive JH7110 USB 2.0 PHY driver
>> + *
>> + * Copyright (C) 2023 StarFive Technology Co., Ltd.
>> + * Author: Minda Chen <minda.chen@starfivetech.com>
>> + */
>> +
>> +#include <linux/bits.h>
>> +#include <linux/clk.h>
>> +#include <linux/err.h>
>> +#include <linux/io.h>
>> +#include <linux/module.h>
>> +#include <linux/phy/phy.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/usb/of.h>
>> +
>> +#define USB_125M_CLK_RATE		125000000
>> +#define USB_LS_KEEPALIVE_OFF		0x4
>> +#define USB_LS_KEEPALIVE_ENABLE		BIT(4)
>> +
>> +struct jh7110_usb2_phy {
>> +	struct phy *phy;
>> +	void __iomem *regs;
>> +	struct clk *usb_125m_clk;
>> +	struct clk *app_125m;
>> +	enum phy_mode mode;
>> +};
>> +
>> +static void jh7110_usb2_mode_set(struct jh7110_usb2_phy *phy)
>> +{
>> +	unsigned int val;
>> +
>> +	if (phy->mode != PHY_MODE_USB_HOST) {
>> +		/* Enable the LS speed keep-alive signal */
>> +		val = readl(phy->regs + USB_LS_KEEPALIVE_OFF);
>> +		val |= USB_LS_KEEPALIVE_ENABLE;
>> +		writel(val, phy->regs + USB_LS_KEEPALIVE_OFF);
>> +	}
>> +}
>> +
>> +static int jh7110_usb2_phy_set_mode(struct phy *_phy,
>> +				    enum phy_mode mode, int submode)
>> +{
>> +	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
>> +
>> +	switch (mode) {
>> +	case PHY_MODE_USB_HOST:
>> +	case PHY_MODE_USB_DEVICE:
>> +	case PHY_MODE_USB_OTG:
>> +		break;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +
>> +	if (mode != phy->mode) {
>> +		dev_info(&_phy->dev, "Changing phy to %d\n", mode);
> 
> dev_dbg() please?
> 
ok, thanks
>> +		phy->mode = mode;
>> +		jh7110_usb2_mode_set(phy);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int jh7110_usb2_phy_init(struct phy *_phy)
>> +{
>> +	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
>> +	int ret;
>> +
>> +	ret = clk_set_rate(phy->usb_125m_clk, USB_125M_CLK_RATE);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = clk_prepare_enable(phy->app_125m);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static int jh7110_usb2_phy_exit(struct phy *_phy)
>> +{
>> +	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
>> +
>> +	clk_disable_unprepare(phy->app_125m);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct phy_ops jh7110_usb2_phy_ops = {
>> +	.init		= jh7110_usb2_phy_init,
>> +	.exit		= jh7110_usb2_phy_exit,
>> +	.set_mode	= jh7110_usb2_phy_set_mode,
>> +	.owner		= THIS_MODULE,
>> +};
>> +
>> +static int jh7110_usb_phy_probe(struct platform_device *pdev)
>> +{
>> +	struct jh7110_usb2_phy *phy;
>> +	struct device *dev = &pdev->dev;
>> +	struct phy_provider *phy_provider;
>> +
>> +	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
>> +	if (!phy)
>> +		return -ENOMEM;
>> +
>> +	phy->usb_125m_clk = devm_clk_get(dev, "125m");
>> +	if (IS_ERR(phy->usb_125m_clk))
>> +		return dev_err_probe(dev, PTR_ERR(phy->usb_125m_clk),
>> +			"Failed to get 125m clock\n");
>> +
>> +	phy->app_125m = devm_clk_get(dev, "app_125m");
>> +	if (IS_ERR(phy->app_125m))
>> +		return dev_err_probe(dev, PTR_ERR(phy->app_125m),
>> +			"Failed to get app 125m clock\n");
>> +
>> +	phy->regs = devm_platform_ioremap_resource(pdev, 0);
>> +	if (IS_ERR(phy->regs))
>> +		return dev_err_probe(dev, PTR_ERR(phy->regs),
>> +			"Failed to map phy base\n");
>> +
>> +	phy->phy = devm_phy_create(dev, NULL, &jh7110_usb2_phy_ops);
>> +	if (IS_ERR(phy->phy))
>> +		return dev_err_probe(dev, PTR_ERR(phy->phy),
>> +			"Failed to create phy\n");
>> +
>> +	platform_set_drvdata(pdev, phy);
>> +	phy_set_drvdata(phy->phy, phy);
>> +	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
>> +
>> +	return PTR_ERR_OR_ZERO(phy_provider);
>> +}
>> +
>> +static int jh7110_usb_phy_remove(struct platform_device *pdev)
>> +{
>> +	struct jh7110_usb2_phy *phy = platform_get_drvdata(pdev);
>> +
>> +	clk_disable_unprepare(phy->app_125m);
> 
> Why do you need to do clk_disable here? You didn't enable it in probe.
> 
OK, Just disable clocks in phy exit
>> +	platform_set_drvdata(pdev, NULL);
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id jh7110_usb_phy_of_match[] = {
>> +	{ .compatible = "starfive,jh7110-usb-phy" },
>> +	{ /* sentinel */ },
>> +};
>> +MODULE_DEVICE_TABLE(of, jh7110_usb_phy_of_match);
>> +
>> +static struct platform_driver jh7110_usb_phy_driver = {
>> +	.probe	= jh7110_usb_phy_probe,
>> +	.remove	= jh7110_usb_phy_remove,
>> +	.driver = {
>> +		.of_match_table	= jh7110_usb_phy_of_match,
>> +		.name  = "jh7110-usb-phy",
>> +	}
>> +};
>> +module_platform_driver(jh7110_usb_phy_driver);
>> +
>> +MODULE_DESCRIPTION("StarFive JH7110 USB 2.0 PHY driver");
>> +MODULE_AUTHOR("Minda Chen <minda.chen@starfivetech.com>");
>> +MODULE_LICENSE("GPL");
> 
> cheers,
> -roger