Re: [PATCH v5 3/7] phy: starfive: Add JH7110 USB 2.0 PHY driver

Roger Quadros
2023-04-24T08:46:59Z

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?

> + 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.

> + 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