[PATCH v3 4/7] mfd: omap: control: usb-phy: introduce the ctrl-module usb driver

Gupta, Ajay Kumar ajay.gupta at ti.com
Mon Jul 9 05:29:19 EDT 2012


Hi,
> On Thu, Jun 28, 2012 at 10:28 AM, Eduardo Valentin
> <eduardo.valentin at ti.com> wrote:
> > Hello,
> >
> > On Wed, Jun 27, 2012 at 10:05:00PM +0400, Konstantin Baydarov wrote:
> >> Created a new platform driver for the platform device created by the
> >> control module mfd core, wrt usb. This driver has API's to power
> on/off the phy and the API's to write to musb mailbox.

USB PHY on am335x platform also need to be enabled using phy control
register in system control module register space.

I think we should make this driver generic enough so that it can be
used by am335x like platforms also to avoid duplication of such drivers.

Ajay
> >>
> >> Changes since previous version:
> >> - Bandgap and usb phy: drivers are now independent from control
> module driver, they use
> >> their own functions to acess scm registers.
> >> - Parent SCM platform device IOMEM resources is used to get the base
> address of SCM window.
> >> - SCM Dependency was removed from Kconfig.
> >> - Bandgap and usb phy: Added private spinlocks for bandgap and usb
> drivers.
> >>
> >> (p.s. the mailbox for musb in omap4 is present in system control
> >> module)
> >>
> >> [kishon at ti.com: wrote the original API's related to USB functions]
> >> Signed-off-by: Konstantin Baydarov <kbaidarov at dev.rtsoft.ru>
> >> Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
> >> Signed-off-by: Eduardo Valentin <eduardo.valentin at ti.com>
> >> ---
> >>  drivers/usb/otg/Kconfig           |   12 +++
> >>  drivers/usb/otg/Makefile          |    1 +
> >>  drivers/usb/otg/omap4-usb-phy.c   |  170
> +++++++++++++++++++++++++++++++++++++
> >>  include/linux/usb/omap4_usb_phy.h |   53 ++++++++++++
> >>  4 files changed, 236 insertions(+), 0 deletions(-)
> >>  create mode 100644 drivers/usb/otg/omap4-usb-phy.c
> >>  create mode 100644 include/linux/usb/omap4_usb_phy.h
> >>
> >> diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
> >> index 5c87db0..0ed691b 100644
> >> --- a/drivers/usb/otg/Kconfig
> >> +++ b/drivers/usb/otg/Kconfig
> >> @@ -78,6 +78,18 @@ config TWL6030_USB
> >>         are hooked to this driver through platform_data structure.
> >>         The definition of internal PHY APIs are in the mach-omap2
> layer.
> >>
> >> +config OMAP4_USB_PHY
> >> +     tristate "Texas Instruments OMAP4+ USB pin control driver"
> >> +     help
> >> +       If you say yes here you get support for the Texas
> Instruments
> >> +       OMAP4+ USB pin control driver. The register set is part of
> system
> >> +       control module.
> >> +
> >> +       USB phy in OMAP configures control module register for
> powering on
> >> +       the phy, configuring VBUSVALID, AVALID, IDDIG and SESSEND.
> For
> >> +       performing the above mentioned configuration, API's are
> added in
> >> +       by this children of the control module driver.
> >> +
> >>  config NOP_USB_XCEIV
> >>       tristate "NOP USB Transceiver Driver"
> >>       select USB_OTG_UTILS
> >> diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
> >> index 41aa509..60c8c83 100644
> >> --- a/drivers/usb/otg/Makefile
> >> +++ b/drivers/usb/otg/Makefile
> >> @@ -13,6 +13,7 @@ obj-$(CONFIG_USB_GPIO_VBUS) += gpio_vbus.o
> >>  obj-$(CONFIG_ISP1301_OMAP)   += isp1301_omap.o
> >>  obj-$(CONFIG_TWL4030_USB)    += twl4030-usb.o
> >>  obj-$(CONFIG_TWL6030_USB)    += twl6030-usb.o
> >> +obj-$(CONFIG_OMAP4_USB_PHY)  += omap4-usb-phy.o
> >>  obj-$(CONFIG_NOP_USB_XCEIV)  += nop-usb-xceiv.o
> >>  obj-$(CONFIG_USB_ULPI)               += ulpi.o
> >>  obj-$(CONFIG_USB_ULPI_VIEWPORT)      += ulpi_viewport.o
> >> diff --git a/drivers/usb/otg/omap4-usb-phy.c
> b/drivers/usb/otg/omap4-usb-phy.c
> >> new file mode 100644
> >> index 0000000..cbea2ea
> >> --- /dev/null
> >> +++ b/drivers/usb/otg/omap4-usb-phy.c
> >> @@ -0,0 +1,170 @@
> >> +/*
> >> + * OMAP4 system control module driver, USB control children
> >> + *
> >> + * Copyright (C) 2012 Texas Instruments Incorporated -
> http://www.ti.com/
> >> + *
> >> + * Contact:
> >> + *    Kishon Vijay Abraham I <kishon at ti.com>
> >> + *    Eduardo Valentin <eduardo.valentin at ti.com>
> >> + *
> >> + * This program is free software; you can redistribute it and/or
> >> + * modify it under the terms of the GNU General Public License
> >> + * version 2 as published by the Free Software Foundation.
> >> + *
> >> + * 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., 51 Franklin St, Fifth Floor, Boston, MA
> >> + * 02110-1301 USA
> >> + *
> >> + */
> >> +
> >> +#include <linux/module.h>
> >> +#include <linux/init.h>
> >> +#include <linux/gpio.h>
> >> +#include <linux/delay.h>
> >> +#include <linux/err.h>
> >> +#include <linux/platform_device.h>
> >> +#include <linux/usb/omap4_usb_phy.h>
> >> +
> >> +void __iomem *omap_usb_phy_base;
> >> +spinlock_t omap_usb_phy_lock;
> >> +
> >> +static int omap_usb_phy_readl(u32 reg, u32 *val)
> >> +{
> >> +     if (!omap_usb_phy_base)
> >> +             return -EINVAL;
> >> +
> >> +     *val = __raw_readl(omap_usb_phy_base + reg);
> >> +     return 0;
> >> +}
> >> +
> >> +/*
> >> + * TODO: Get rid from omap_usb_phy_writel() return value -
> >> + * It's useless.
> >
> > if you do that remember to keep a WARN_ON in case the base address is
> not set.
> >
> >> + */
> >> +static int omap_usb_phy_writel(u32 val, u32 reg)
> >> +{
> >> +     unsigned long flags;
> >> +
> >> +     if (!omap_usb_phy_base)
> >> +             return -EINVAL;
> >> +
> >> +     spin_lock_irqsave(&omap_usb_phy_lock, flags);
> >> +     __raw_writel(val, omap_usb_phy_base + reg);
> >> +     spin_unlock_irqrestore(&omap_usb_phy_lock, flags);
> >
> > I think it is better to lock per operation than per write.
> >
> >> +     return 0;
> >> +}
> >> +
> >> +/**
> >> + * omap4_usb_phy_power - power on/off the phy using control module
> reg
> >> + * @dev: struct device *
> >> + * @on: 0 or 1, based on powering on or off the PHY
> >> + *
> >> + * omap_usb2 can call this API to power on or off the PHY.
> >> + */
> >> +int omap4_usb_phy_power(struct device *dev, int on)
> >> +{
> >> +     u32 val;
> >> +     int ret;
> >> +
> >> +     if (on) {
> >> +             ret = omap_usb_phy_readl(CONTROL_DEV_CONF, &val);
> >> +             if (!ret && (val & PHY_PD)) {
> >> +                     ret = omap_usb_phy_writel(~PHY_PD,
> >> +                                               CONTROL_DEV_CONF);
> >> +                     /* XXX: add proper documentation for this
> delay */
> >> +                     mdelay(200);
> >> +             }
> >> +     } else
> >> +             ret = omap_usb_phy_writel(PHY_PD, CONTROL_DEV_CONF);
> >> +
> >> +     return ret;
> >> +}
> >> +EXPORT_SYMBOL_GPL(omap4_usb_phy_power);
> >> +
> >> +/**
> >> + * omap4_usb_phy_mailbox - write to usb otg mailbox
> >> + * @dev: struct device *
> >> + * @val: the value to be written to the mailbox
> >> + *
> >> + * On detection of a device (ID pin is grounded), the phy should
> call this API
> >> + * to set AVALID, VBUSVALID and ID pin is grounded.
> >> + *
> >> + * When OMAP is connected to a host (OMAP in device mode), the phy
> should call
> >> + * this API to set AVALID, VBUSVALID and ID pin in high impedance.
> >> + *
> >> + * The phy should call this API, if OMAP is disconnected from host
> or device.
> >> + */
> >> +int omap4_usb_phy_mailbox(struct device *dev, u32 val)
> >> +{
> >> +     return omap_usb_phy_writel(val, CONTROL_USBOTGHS_CONTROL);
> >> +}
> >> +EXPORT_SYMBOL_GPL(omap4_usb_phy_mailbox);
> >> +
> >> +static int __devinit omap_usb_phy_probe(struct platform_device
> *pdev)
> >> +{
> >> +     struct resource *io_res;
> >> +     struct platform_device *pparent;
> >> +
> >> +     if (!pdev->dev.parent) {
> >> +             dev_err(&pdev->dev, "No parent device!\n");
> >> +             return -ENOMEM;
> >> +     }
> >> +
> >> +     pparent = to_platform_device(pdev->dev.parent);
> >> +
> >> +     io_res = platform_get_resource(pparent, IORESOURCE_MEM, 0);
> >
> > Can someone please explain me what do we gain by doing this at
> children code?
> >
> >> +     if (!io_res)
> >> +             return -ENOENT;
> >> +
> >> +     omap_usb_phy_base = ioremap(io_res->start,
> resource_size(io_res));
> >> +     if (!omap_usb_phy_base)
> >> +             return -ENOMEM;
> >> +
> >> +     /* Initialize register lock */
> >> +     spin_lock_init(&omap_usb_phy_lock);
> >> +
> >> +     return 0;
> >> +}
> >> +
> >> +static int __devexit omap_usb_phy_remove(struct platform_device
> *pdev)
> >> +{
> >> +     return 0;
> >> +}
> >> +
> >> +static const struct of_device_id of_omap_usb_phy_match[] = {
> >> +     { .compatible = "ti,omap4-usb-phy", },
> >> +     { },
> >> +};
> >> +
> >> +static struct platform_driver omap_usb_phy_driver = {
> >> +     .probe = omap_usb_phy_probe,
> >> +     .remove = __devexit_p(omap_usb_phy_remove),
> >> +     .driver = {
> >> +                     .name   = "omap4-usb-phy",
> >> +                     .owner  = THIS_MODULE,
> >> +                     .of_match_table = of_omap_usb_phy_match,
> >> +     },
> >> +};
> >> +
> >> +static int __init omap_usb_phy_init(void)
> >> +{
> >> +     return platform_driver_register(&omap_usb_phy_driver);
> >> +}
> >> +postcore_initcall(omap_usb_phy_init);
> >> +
> >> +static void __exit omap_usb_phy_exit(void)
> >> +{
> >> +     platform_driver_unregister(&omap_usb_phy_driver);
> >> +}
> >> +module_exit(omap_usb_phy_exit);
> >> +
> >> +MODULE_DESCRIPTION("OMAP4+ USB-phy driver");
> >> +MODULE_LICENSE("GPL");
> >> +MODULE_ALIAS("platform: omap4-usb-phy");
> >> +MODULE_AUTHOR("Texas Instrument Inc.");
> >> diff --git a/include/linux/usb/omap4_usb_phy.h
> b/include/linux/usb/omap4_usb_phy.h
> >> new file mode 100644
> >> index 0000000..b6a4701
> >> --- /dev/null
> >> +++ b/include/linux/usb/omap4_usb_phy.h
> >> @@ -0,0 +1,53 @@
> >> +/*
> >> + * OMAP4 USB-phy
> >> + *
> >> + * Copyright (C) 2012 Texas Instruments Incorporated -
> http://www.ti.com/
> >> + *
> >> + * Contact:
> >> + *    Kishon Vijay Abraham I <kishon at ti.com>
> >> + *    Eduardo Valentin <eduardo.valentin at ti.com>
> >> + *
> >> + * This program is free software; you can redistribute it and/or
> >> + * modify it under the terms of the GNU General Public License
> >> + * version 2 as published by the Free Software Foundation.
> >> + *
> >> + * 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., 51 Franklin St, Fifth Floor, Boston, MA
> >> + * 02110-1301 USA
> >> + *
> >> + */
> >> +
> >> +#ifndef __OMAP4_USB_PHY_H
> >> +#define __OMAP4_USB_PHY_H
> >> +
> >> +#define      PHY_PD                          0x1
> >> +#define      AVALID                          BIT(0)
> >> +#define      BVALID                          BIT(1)
> >> +#define      VBUSVALID                       BIT(2)
> >> +#define      SESSEND                         BIT(3)
> >> +#define      IDDIG                           BIT(4)
> >> +#define      CONTROL_DEV_CONF                0x00000300
> >> +#define      CONTROL_USBOTGHS_CONTROL        0x0000033C
> >> +
> >> +/* USB-PHY helpers */
> >> +#if (defined(CONFIG_OMAP4_USB_PHY)) ||
> (defined(CONFIG_OMAP4_USB_PHY_MODULE))
> >> +extern int omap4_usb_phy_mailbox(struct device *dev, u32 val);
> >> +extern int omap4_usb_phy_power(struct device *dev, int on);
> >> +#else
> >> +static inline int omap4_usb_phy_mailbox(struct device *dev, u32
> val)
> >> +{
> >> +     return 0;
> >> +}
> >> +static inline int omap4_usb_phy_power(struct device *dev, int on)
> >> +{
> >> +     return 0;
> >> +}
> >> +#endif
> >> +
> >> +#endif
> >> --
> >> 1.7.7.6
> >>
> >>



More information about the linux-arm-kernel mailing list