Re: [PATCH v7 13/14] usb: otg: add basic mxs phy driver support

[Richard Zhao <richard.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>]

On Mon, Jun 25, 2012 at 02:56:30PM +0800, Richard Zhao wrote:
> mxs phy is used in Freescale i.MX SoCs, for example
> imx23, imx28, imx6Q. This patch adds the basic host
> support.
> 
> Signed-off-by: Richard Zhao <richard.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
> Signed-off-by: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
> Cc: Peter Chen <peter.chen-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
> Acked-by: Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>
> Tested-by: Subodh Nijsure <snijsure-4jo+YWezP1RWk0Htik3J/w@public.gmane.org>
> ---
>  Documentation/devicetree/bindings/usb/mxs-phy.txt |   13 ++
>  drivers/usb/otg/Kconfig                           |    9 +
>  drivers/usb/otg/Makefile                          |    1 +
>  drivers/usb/otg/mxs-phy.c                         |  197 +++++++++++++++++++++
>  4 files changed, 220 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/mxs-phy.txt
>  create mode 100644 drivers/usb/otg/mxs-phy.c
> 
> diff --git a/Documentation/devicetree/bindings/usb/mxs-phy.txt b/Documentation/devicetree/bindings/usb/mxs-phy.txt
> new file mode 100644
> index 0000000..5835b27
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/mxs-phy.txt
> @@ -0,0 +1,13 @@
> +* Freescale MXS USB Phy Device
> +
> +Required properties:
> +- compatible: Should be "fsl,imx23-usbphy"
> +- reg: Should contain registers location and length
> +- interrupts: Should contain phy interrupt
> +
> +Example:
> +usbphy1: usbphy@020c9000 {
> +	compatible = "fsl,imx6q-usbphy", "fsl,imx23-usbphy";
> +	reg = <0x020c9000 0x1000>;
> +	interrupts = <0 44 0x04>;
> +};
> diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
> index 5c87db0..669eb32 100644
> --- a/drivers/usb/otg/Kconfig
> +++ b/drivers/usb/otg/Kconfig
> @@ -116,6 +116,15 @@ config FSL_USB2_OTG
>  	help
>  	  Enable this to support Freescale USB OTG transceiver.
>  
> +config USB_MXS_PHY
> +	tristate "Freescale MXS USB PHY support"
> +	select STMP_DEVICE
> +	select USB_OTG_UTILS
> +	help
> +	  Enable this to support the Freescale MXS USB PHY.
> +
> +	  MXS Phy is used by some of the i.MX SoCs, for example imx23/28/6x.
> +
>  config USB_MV_OTG
>  	tristate "Marvell USB OTG support"
>  	depends on USB_EHCI_MV && USB_MV_UDC && USB_SUSPEND
> diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
> index 41aa509..a844b8d 100644
> --- a/drivers/usb/otg/Makefile
> +++ b/drivers/usb/otg/Makefile
> @@ -20,4 +20,5 @@ obj-$(CONFIG_USB_MSM_OTG)	+= msm_otg.o
>  obj-$(CONFIG_AB8500_USB)	+= ab8500-usb.o
>  fsl_usb2_otg-objs		:= fsl_otg.o otg_fsm.o
>  obj-$(CONFIG_FSL_USB2_OTG)	+= fsl_usb2_otg.o
> +obj-$(CONFIG_USB_MXS_PHY)	+= mxs-phy.o
>  obj-$(CONFIG_USB_MV_OTG)	+= mv_otg.o
> diff --git a/drivers/usb/otg/mxs-phy.c b/drivers/usb/otg/mxs-phy.c
> new file mode 100644
> index 0000000..d64c1fe
> --- /dev/null
> +++ b/drivers/usb/otg/mxs-phy.c
> @@ -0,0 +1,197 @@
> +/*
> + * Copyright 2012 Freescale Semiconductor, Inc.
> + * Copyright (C) 2012 Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
> + * on behalf of DENX Software Engineering GmbH
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/platform_device.h>
> +#include <linux/clk.h>
> +#include <linux/usb/otg.h>
> +#include <linux/stmp_device.h>
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +
> +#define DRIVER_NAME "mxs_phy"
> +
> +#define HW_USBPHY_PWD				0x00
> +#define HW_USBPHY_CTRL				0x30
> +#define HW_USBPHY_CTRL_SET			0x34
> +#define HW_USBPHY_CTRL_CLR			0x38
> +
> +#define BM_USBPHY_CTRL_SFTRST			BIT(31)
> +#define BM_USBPHY_CTRL_CLKGATE			BIT(30)
> +#define BM_USBPHY_CTRL_ENUTMILEVEL3		BIT(15)
> +#define BM_USBPHY_CTRL_ENUTMILEVEL2		BIT(14)
> +#define BM_USBPHY_CTRL_ENHOSTDISCONDETECT	BIT(1)
> +
> +struct mxs_phy {
> +	struct usb_phy phy;
> +	struct clk *clk;
> +	int connected:1;
> +};
> +
> +#define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
> +
> +static void mxs_phy_hw_init(struct mxs_phy *mxs_phy)
> +{
> +	void __iomem *base = mxs_phy->phy.io_priv;
> +
> +	stmp_reset_block(base + HW_USBPHY_CTRL);
> +
> +	/* Power up the PHY */
> +	writel_relaxed(0, base + HW_USBPHY_PWD);
> +
> +	/* enable FS/LS device */
> +	writel_relaxed(BM_USBPHY_CTRL_ENUTMILEVEL2 |
> +			BM_USBPHY_CTRL_ENUTMILEVEL3,
> +			base + HW_USBPHY_CTRL_SET);
> +}
> +
> +static int mxs_phy_init(struct usb_phy *phy)
> +{
> +	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
> +
> +	clk_prepare_enable(mxs_phy->clk);
> +	mxs_phy_hw_init(mxs_phy);
> +
> +	return 0;
> +}
> +
> +static void mxs_phy_shutdown(struct usb_phy *phy)
> +{
> +	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
> +
> +	writel_relaxed(BM_USBPHY_CTRL_CLKGATE,
> +			phy->io_priv + HW_USBPHY_CTRL_SET);
> +
> +	clk_disable_unprepare(mxs_phy->clk);
> +}
> +
> +static int mxs_phy_on_connect(struct usb_phy *phy, int port)
> +{
> +	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
> +
> +	dev_dbg(phy->dev, "Connect on port %d\n", port);
> +
> +	if (mxs_phy->connected)
> +		return 0;
I'll have to remove all connected checking. When hcd driver is removed,
it won't call notify_disconnect. It corrupt the "connected" state. so
I have to remove the checking.

Thanks
Richard
> +	mxs_phy_hw_init(to_mxs_phy(phy));
> +	writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
> +			phy->io_priv + HW_USBPHY_CTRL_SET);
> +	mxs_phy->connected = 1;
> +
> +	return 0;
> +}
> +
> +static int mxs_phy_on_disconnect(struct usb_phy *phy, int port)
> +{
> +	struct mxs_phy *mxs_phy = to_mxs_phy(phy);
> +
> +	dev_dbg(phy->dev, "Disconnect on port %d\n", port);
> +
> +	if (!mxs_phy->connected)
> +		return 0;
> +	writel_relaxed(BM_USBPHY_CTRL_ENHOSTDISCONDETECT,
> +			phy->io_priv + HW_USBPHY_CTRL_CLR);
> +	mxs_phy->connected = 0;
> +
> +	return 0;
> +}
> +
> +static int mxs_phy_probe(struct platform_device *pdev)
> +{
> +	struct resource *res;
> +	void __iomem *base;
> +	struct clk *clk;
> +	struct mxs_phy *mxs_phy;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		dev_err(&pdev->dev, "can't get device resources\n");
> +		return -ENOENT;
> +	}
> +
> +	base = devm_request_and_ioremap(&pdev->dev, res);
> +	if (!base)
> +		return -EBUSY;
> +
> +	clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(clk)) {
> +		dev_err(&pdev->dev,
> +			"can't get the clock, err=%ld", PTR_ERR(clk));
> +		return PTR_ERR(clk);
> +	}
> +
> +	mxs_phy = devm_kzalloc(&pdev->dev, sizeof(*mxs_phy), GFP_KERNEL);
> +	if (!mxs_phy) {
> +		dev_err(&pdev->dev, "Failed to allocate USB PHY structure!\n");
> +		return -ENOMEM;
> +	}
> +
> +	mxs_phy->phy.io_priv		= base;
> +	mxs_phy->phy.dev		= &pdev->dev;
> +	mxs_phy->phy.label		= DRIVER_NAME;
> +	mxs_phy->phy.init		= mxs_phy_init;
> +	mxs_phy->phy.shutdown		= mxs_phy_shutdown;
> +	mxs_phy->phy.notify_connect	= mxs_phy_on_connect;
> +	mxs_phy->phy.notify_disconnect	= mxs_phy_on_disconnect;
> +
> +	ATOMIC_INIT_NOTIFIER_HEAD(&mxs_phy->phy.notifier);
> +
> +	mxs_phy->clk = clk;
> +
> +	platform_set_drvdata(pdev, &mxs_phy->phy);
> +
> +	return 0;
> +}
> +
> +static int __devexit mxs_phy_remove(struct platform_device *pdev)
> +{
> +	platform_set_drvdata(pdev, NULL);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id mxs_phy_dt_ids[] = {
> +	{ .compatible = "fsl,imx23-usbphy", },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, mxs_phy_dt_ids);
> +
> +static struct platform_driver mxs_phy_driver = {
> +	.probe = mxs_phy_probe,
> +	.remove = __devexit_p(mxs_phy_remove),
> +	.driver = {
> +		.name = DRIVER_NAME,
> +		.owner	= THIS_MODULE,
> +		.of_match_table = mxs_phy_dt_ids,
> +	 },
> +};
> +
> +static int __init mxs_phy_module_init(void)
> +{
> +	return platform_driver_register(&mxs_phy_driver);
> +}
> +postcore_initcall(mxs_phy_module_init);
> +
> +static void __exit mxs_phy_module_exit(void)
> +{
> +	platform_driver_unregister(&mxs_phy_driver);
> +}
> +module_exit(mxs_phy_module_exit);
> +
> +MODULE_ALIAS("platform:mxs-usb-phy");
> +MODULE_AUTHOR("Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>");
> +MODULE_AUTHOR("Richard Zhao <richard.zhao-KZfg59tc24xl57MIdRCFDg@public.gmane.org>");
> +MODULE_DESCRIPTION("Freescale MXS USB PHY driver");
> +MODULE_LICENSE("GPL");
> -- 
> 1.7.9.5
>