Re: [RFC PATCH 1/3] drivers: usb: otg: add a new driver for omap usb2 phy

["Shilimkar, Santosh" <santosh.shilimkar@ti.com>]

On Wed, May 30, 2012 at 8:04 PM, Kishon Vijay Abraham I <kishon@ti.com> wrote:
> All phy related programming like enabling/disabling the clocks, powering
> on/off the phy is taken care of by this driver. It is also used for OTG
> related functionality like srp.
>
> Cc: Felipe Balbi <balbi@ti.com>
> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
> ---
>  drivers/usb/otg/Kconfig           |   17 ++-
>  drivers/usb/otg/Makefile          |    1 +
>  drivers/usb/otg/omap-usb2.c       |  232 +++++++++++++++++++++++++++++++++++++
>  include/linux/usb/omap_usb.h      |   47 ++++++++
>  include/linux/usb/phy_companion.h |   34 ++++++
>  5 files changed, 327 insertions(+), 4 deletions(-)
>  create mode 100644 drivers/usb/otg/omap-usb2.c
>  create mode 100644 include/linux/usb/omap_usb.h
>  create mode 100644 include/linux/usb/phy_companion.h
>

[...]

> diff --git a/drivers/usb/otg/omap-usb2.c b/drivers/usb/otg/omap-usb2.c
> new file mode 100644
> index 0000000..ccd74b6
> --- /dev/null
> +++ b/drivers/usb/otg/omap-usb2.c
> @@ -0,0 +1,232 @@
> +/*
> + * omap-usb2.c - USB PHY, talking to musb controller in OMAP.
> + *
> + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com
s/2011/2012
> + * 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.
> + *
> + * Author: Kishon Vijay Abraham I <kishon@ti.com>
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/of.h>
> +#include <linux/usb/omap_usb.h>
> +#include <linux/usb/phy_companion.h>
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/delay.h>
Do you need it ?

> +#include <linux/mfd/omap_control.h>
> +#include <linux/usb/omap4_usb_phy.h>
> +
> +/**
> + * omap_usb2_set_comparator - links the comparator present in the sytem with
> + *     this phy
> + * @comparator - the companion phy(comparator) for this phy
> + *
> + * The phy companion driver should call this API passing the phy_companion
> + * filled with set_vbus and start_srp to be used by usb phy.
> + *
> + * For use by phy companion driver
> + */
> +void omap_usb2_set_comparator(struct phy_companion *comparator)
> +{
> +       struct usb_phy  *x = usb_get_phy(USB_PHY_TYPE_USB2);
> +       struct omap_usb *phy = phy_to_omapusb(x);
> +
> +       phy->comparator = comparator;
> +}
> +EXPORT_SYMBOL_GPL(omap_usb2_set_comparator);
> +
> +static int omap_usb_set_vbus(struct usb_otg *otg, bool enabled)
> +{
> +       struct omap_usb *phy = phy_to_omapusb(otg->phy);
> +
> +       if (!phy->comparator)
> +               return -ENODEV;
> +
> +       return phy->comparator->set_vbus(phy->comparator, enabled);
> +}
> +
> +static int omap_usb_start_srp(struct usb_otg *otg)
> +{
> +       struct omap_usb *phy = phy_to_omapusb(otg->phy);
> +
> +       if (!phy->comparator)
> +               return -ENODEV;
> +
> +       return phy->comparator->start_srp(phy->comparator);
> +}
> +
> +static int omap_usb_set_host(struct usb_otg *otg, struct usb_bus *host)
> +{
> +       struct usb_phy  *phy = otg->phy;
> +
> +       otg->host = host;
> +       if (!host)
> +               phy->state = OTG_STATE_UNDEFINED;
> +
> +       return 0;
> +}
> +
> +static int omap_usb_set_peripheral(struct usb_otg *otg,
> +               struct usb_gadget *gadget)
> +{
> +       struct usb_phy  *phy = otg->phy;
> +
> +       otg->gadget = gadget;
> +       if (!gadget)
> +               phy->state = OTG_STATE_UNDEFINED;
> +
> +       return 0;
> +}
> +
> +static int omap_usb2_suspend(struct usb_phy *x, int suspend)
> +{
> +       struct omap_usb *phy = phy_to_omapusb(x);
> +
> +       if (suspend && !phy->is_suspended) {
> +               pm_runtime_put_sync(phy->dev);
> +               phy->is_suspended = 1;
> +       } else if (!suspend && phy->is_suspended) {
> +               pm_runtime_get_sync(phy->dev);
> +               phy->is_suspended = 0;
> +       }
> +
> +       return 0;
> +}
> +
> +static int __devinit omap_usb2_probe(struct platform_device *pdev)
> +{
> +       struct omap_usb                 *phy;
> +       struct usb_otg                  *otg;
> +
> +       phy = devm_kzalloc(&pdev->dev, sizeof(*phy), GFP_KERNEL);
> +       if (!phy) {
> +               dev_err(&pdev->dev, "unable to allocate memory for USB2 PHY\n");
> +               return -ENOMEM;
> +       }
> +
> +       otg = devm_kzalloc(&pdev->dev, sizeof(*otg), GFP_KERNEL);
> +       if (!otg) {
> +               dev_err(&pdev->dev, "unable to allocate memory for USB OTG\n");
> +               return -ENOMEM;
> +       }
> +
> +       phy->dev                = &pdev->dev;
> +
> +       phy->phy.dev            = phy->dev;
> +       phy->phy.label          = "omap-usb2";
> +       phy->phy.set_suspend    = omap_usb2_suspend;
> +       phy->phy.otg            = otg;
> +
> +       phy->control_dev        = omap_control_get();
> +       if (IS_ERR(phy->control_dev)) {
> +               dev_err(&pdev->dev, "no control device present in system\n");
> +               return PTR_ERR(phy->control_dev);
> +       }
> +
> +       phy->is_suspended       = 1;
> +       omap4_usb_phy_power(phy->control_dev, 0);
> +
> +       otg->set_host           = omap_usb_set_host;
> +       otg->set_peripheral     = omap_usb_set_peripheral;
> +       otg->set_vbus           = omap_usb_set_vbus;
> +       otg->start_srp          = omap_usb_start_srp;
> +       otg->phy                = &phy->phy;
> +
> +       phy->wkupclk = clk_get(phy->dev, "usb_phy_cm_clk32k");
Error check missing here.

> +
> +       usb_add_phy(&phy->phy, USB_PHY_TYPE_USB2);
> +
unnecessary extra line
> +       platform_set_drvdata(pdev, phy);
> +
this one too
> +       pm_runtime_enable(phy->dev);
> +
> +       return 0;
> +}
> +
> +static int __devexit omap_usb2_remove(struct platform_device *pdev)
> +{
> +       struct omap_usb *phy = platform_get_drvdata(pdev);
> +
> +       usb_remove_phy(&phy->phy);
> +       platform_set_drvdata(pdev, NULL);
> +
> +       return 0;
> +}
> +
> +#ifdef CONFIG_PM
s/ CONFIG_PM/CONFIG_SUSPEND
otherwise you will get build warning with !CONFIG_SUSPEND

> +
> +static int omap_usb2_runtime_suspend(struct device *dev)
> +{
> +       struct platform_device  *pdev = to_platform_device(dev);
> +       struct omap_usb *phy = platform_get_drvdata(pdev);
> +
> +       clk_disable(phy->wkupclk);
> +       omap4_usb_phy_power(phy->control_dev, 0);
> +
> +       return 0;
> +}
> +
> +static int omap_usb2_runtime_resume(struct device *dev)
> +{
> +       struct platform_device  *pdev = to_platform_device(dev);
> +       struct omap_usb *phy = platform_get_drvdata(pdev);
> +
> +       omap4_usb_phy_power(phy->control_dev, 1);
> +       clk_enable(phy->wkupclk);
> +
> +       return 0;
> +}
> +
> +static const struct dev_pm_ops omap_usb2_pm_ops = {
> +       SET_RUNTIME_PM_OPS(omap_usb2_runtime_suspend, omap_usb2_runtime_resume,
> +               NULL)
> +};
> +
> +#define DEV_PM_OPS     (&omap_usb2_pm_ops)
> +#else
> +#define DEV_PM_OPS     NULL
> +#endif
> +
> +static struct platform_driver omap_usb2_driver = {
> +       .probe          = omap_usb2_probe,
> +       .remove         = __devexit_p(omap_usb2_remove),
> +       .driver         = {
> +               .name   = "omap-usb2",
> +               .owner  = THIS_MODULE,
> +               .pm     = DEV_PM_OPS,
> +       },
> +};
> +
> +static int __init usb2_omap_init(void)
> +{
> +       return platform_driver_register(&omap_usb2_driver);
> +}
> +arch_initcall(usb2_omap_init);
> +
> +static void __exit usb2_omap_exit(void)
> +{
> +       platform_driver_unregister(&omap_usb2_driver);
> +}
> +module_exit(usb2_omap_exit);
> +
> +MODULE_ALIAS("platform: omap_usb2");
> +MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
> +MODULE_DESCRIPTION("OMAP USB2 PHY DRIVER");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/usb/omap_usb.h b/include/linux/usb/omap_usb.h
> new file mode 100644
> index 0000000..8d781df
> --- /dev/null
> +++ b/include/linux/usb/omap_usb.h
> @@ -0,0 +1,47 @@
> +/*
> + * omap_usb.h -- omap usb2 phy header file
> + *
> + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com
s/2011/2012

> + * 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.
> + *
> + * Author: Kishon Vijay Abraham I <kishon@ti.com>
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + *
> + */
> +
> +#ifndef __DRIVERS_OMAP_USB2_H
> +#define __DRIVERS_OMAP_USB2_H
> +
> +#include <linux/usb/otg.h>
> +
> +struct omap_usb {
> +       struct usb_phy          phy;
> +       struct phy_companion    *comparator;
> +       struct device           *dev;
> +       struct device           *control_dev;
> +       struct clk              *wkupclk;
> +       u8                      is_suspended:1;
> +};
> +
> +#define        phy_to_omapusb(x)       container_of((x), struct omap_usb, phy)
> +
> +#if defined(CONFIG_OMAP_USB2) || defined(CONFIG_OMAP_USB2_MODULE)
> +void omap_usb2_set_comparator(struct phy_companion *comparator);
> +#else
> +static inline void omap_usb2_set_comparator(struct phy_companion *comparator)
> +{
> +}
> +#endif
> +
> +#endif /* __DRIVERS_OMAP_USB_H */
> diff --git a/include/linux/usb/phy_companion.h b/include/linux/usb/phy_companion.h
> new file mode 100644
> index 0000000..321290f
> --- /dev/null
> +++ b/include/linux/usb/phy_companion.h
> @@ -0,0 +1,34 @@
> +/*
> + * phy-companion.h -- phy companion to indicate the comparator part of PHY
> + *
> + * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com
Here too..

Regards
Santosh