[PATCH v3 4/7] mfd: omap: control: usb-phy: introduce the ctrl-module usb driver
ABRAHAM, KISHON VIJAY
kishon at ti.com
Mon Jul 9 05:23:34 EDT 2012
+Ajay
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.
>>
>> 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
>>
>>
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