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alistair23-linux/drivers/usb/dwc2/platform.c
Vardan Mikayelyan 13b1f8e25b usb: dwc2: Force mode optimizations 
If the dr_mode is USB_DR_MODE_OTG, forcing the mode is needed during
driver probe to get the host and device specific HW parameters. Then we
clear the force mode bits so that the core operates in OTG mode.

The force mode bits should not be touched at any other time during the
driver lifetime and they should be preserved whenever the GUSBCFG
register is written to. The force mode bit values will persist across
soft resets of the core.

If the dr_mode is either USB_DR_MODE_HOST or USB_DR_MODE_PERIPHERAL, the
force mode is set just once at probe to configure the core as either a
host or peripheral.

Given the above, we no longer need any other reset delays, force delays,
or any forced modes anywhere else in the driver. So replace all calls to
dwc2_core_reset_and_force_dr_mode() with dwc2_core_reset() and remove
all other unnecessary delays.

Also remove the dwc2_force_mode_if_needed() function since the "if
needed" part is already taken care of by the polling in
dwc2_force_mode().

Finally, remove all other calls to dwc2_clear_force_mode().

Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Vardan Mikayelyan <mvardan@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
2018-03-13 10:47:58 +02:00

534 lines
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// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
* platform.c - DesignWare HS OTG Controller platform driver
*
* Copyright (C) Matthijs Kooijman <matthijs@stdin.nl>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The names of the above-listed copyright holders may not be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* ALTERNATIVELY, this software may be distributed under the terms of the
* GNU General Public License ("GPL") as published by the Free Software
* Foundation; either version 2 of the License, or (at your option) any
* later version.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/of_device.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_data/s3c-hsotg.h>
#include <linux/reset.h>
#include <linux/usb/of.h>
#include "core.h"
#include "hcd.h"
#include "debug.h"
static const char dwc2_driver_name[] = "dwc2";
/*
* Check the dr_mode against the module configuration and hardware
* capabilities.
*
* The hardware, module, and dr_mode, can each be set to host, device,
* or otg. Check that all these values are compatible and adjust the
* value of dr_mode if possible.
*
* actual
* HW MOD dr_mode dr_mode
* ------------------------------
* HST HST any : HST
* HST DEV any : ---
* HST OTG any : HST
*
* DEV HST any : ---
* DEV DEV any : DEV
* DEV OTG any : DEV
*
* OTG HST any : HST
* OTG DEV any : DEV
* OTG OTG any : dr_mode
*/
static int dwc2_get_dr_mode(struct dwc2_hsotg *hsotg)
{
enum usb_dr_mode mode;
hsotg->dr_mode = usb_get_dr_mode(hsotg->dev);
if (hsotg->dr_mode == USB_DR_MODE_UNKNOWN)
hsotg->dr_mode = USB_DR_MODE_OTG;
mode = hsotg->dr_mode;
if (dwc2_hw_is_device(hsotg)) {
if (IS_ENABLED(CONFIG_USB_DWC2_HOST)) {
dev_err(hsotg->dev,
"Controller does not support host mode.\n");
return -EINVAL;
}
mode = USB_DR_MODE_PERIPHERAL;
} else if (dwc2_hw_is_host(hsotg)) {
if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL)) {
dev_err(hsotg->dev,
"Controller does not support device mode.\n");
return -EINVAL;
}
mode = USB_DR_MODE_HOST;
} else {
if (IS_ENABLED(CONFIG_USB_DWC2_HOST))
mode = USB_DR_MODE_HOST;
else if (IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL))
mode = USB_DR_MODE_PERIPHERAL;
}
if (mode != hsotg->dr_mode) {
dev_warn(hsotg->dev,
"Configuration mismatch. dr_mode forced to %s\n",
mode == USB_DR_MODE_HOST ? "host" : "device");
hsotg->dr_mode = mode;
}
return 0;
}
static int __dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
{
struct platform_device *pdev = to_platform_device(hsotg->dev);
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(hsotg->supplies),
hsotg->supplies);
if (ret)
return ret;
if (hsotg->clk) {
ret = clk_prepare_enable(hsotg->clk);
if (ret)
return ret;
}
if (hsotg->uphy) {
ret = usb_phy_init(hsotg->uphy);
} else if (hsotg->plat && hsotg->plat->phy_init) {
ret = hsotg->plat->phy_init(pdev, hsotg->plat->phy_type);
} else {
ret = phy_power_on(hsotg->phy);
if (ret == 0)
ret = phy_init(hsotg->phy);
}
return ret;
}
/**
* dwc2_lowlevel_hw_enable - enable platform lowlevel hw resources
* @hsotg: The driver state
*
* A wrapper for platform code responsible for controlling
* low-level USB platform resources (phy, clock, regulators)
*/
int dwc2_lowlevel_hw_enable(struct dwc2_hsotg *hsotg)
{
int ret = __dwc2_lowlevel_hw_enable(hsotg);
if (ret == 0)
hsotg->ll_hw_enabled = true;
return ret;
}
static int __dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
{
struct platform_device *pdev = to_platform_device(hsotg->dev);
int ret = 0;
if (hsotg->uphy) {
usb_phy_shutdown(hsotg->uphy);
} else if (hsotg->plat && hsotg->plat->phy_exit) {
ret = hsotg->plat->phy_exit(pdev, hsotg->plat->phy_type);
} else {
ret = phy_exit(hsotg->phy);
if (ret == 0)
ret = phy_power_off(hsotg->phy);
}
if (ret)
return ret;
if (hsotg->clk)
clk_disable_unprepare(hsotg->clk);
ret = regulator_bulk_disable(ARRAY_SIZE(hsotg->supplies),
hsotg->supplies);
return ret;
}
/**
* dwc2_lowlevel_hw_disable - disable platform lowlevel hw resources
* @hsotg: The driver state
*
* A wrapper for platform code responsible for controlling
* low-level USB platform resources (phy, clock, regulators)
*/
int dwc2_lowlevel_hw_disable(struct dwc2_hsotg *hsotg)
{
int ret = __dwc2_lowlevel_hw_disable(hsotg);
if (ret == 0)
hsotg->ll_hw_enabled = false;
return ret;
}
static int dwc2_lowlevel_hw_init(struct dwc2_hsotg *hsotg)
{
int i, ret;
hsotg->reset = devm_reset_control_get_optional(hsotg->dev, "dwc2");
if (IS_ERR(hsotg->reset)) {
ret = PTR_ERR(hsotg->reset);
dev_err(hsotg->dev, "error getting reset control %d\n", ret);
return ret;
}
reset_control_deassert(hsotg->reset);
hsotg->reset_ecc = devm_reset_control_get_optional(hsotg->dev, "dwc2-ecc");
if (IS_ERR(hsotg->reset_ecc)) {
ret = PTR_ERR(hsotg->reset_ecc);
dev_err(hsotg->dev, "error getting reset control for ecc %d\n", ret);
return ret;
}
reset_control_deassert(hsotg->reset_ecc);
/* Set default UTMI width */
hsotg->phyif = GUSBCFG_PHYIF16;
/*
* Attempt to find a generic PHY, then look for an old style
* USB PHY and then fall back to pdata
*/
hsotg->phy = devm_phy_get(hsotg->dev, "usb2-phy");
if (IS_ERR(hsotg->phy)) {
ret = PTR_ERR(hsotg->phy);
switch (ret) {
case -ENODEV:
case -ENOSYS:
hsotg->phy = NULL;
break;
case -EPROBE_DEFER:
return ret;
default:
dev_err(hsotg->dev, "error getting phy %d\n", ret);
return ret;
}
}
if (!hsotg->phy) {
hsotg->uphy = devm_usb_get_phy(hsotg->dev, USB_PHY_TYPE_USB2);
if (IS_ERR(hsotg->uphy)) {
ret = PTR_ERR(hsotg->uphy);
switch (ret) {
case -ENODEV:
case -ENXIO:
hsotg->uphy = NULL;
break;
case -EPROBE_DEFER:
return ret;
default:
dev_err(hsotg->dev, "error getting usb phy %d\n",
ret);
return ret;
}
}
}
hsotg->plat = dev_get_platdata(hsotg->dev);
if (hsotg->phy) {
/*
* If using the generic PHY framework, check if the PHY bus
* width is 8-bit and set the phyif appropriately.
*/
if (phy_get_bus_width(hsotg->phy) == 8)
hsotg->phyif = GUSBCFG_PHYIF8;
}
/* Clock */
hsotg->clk = devm_clk_get(hsotg->dev, "otg");
if (IS_ERR(hsotg->clk)) {
hsotg->clk = NULL;
dev_dbg(hsotg->dev, "cannot get otg clock\n");
}
/* Regulators */
for (i = 0; i < ARRAY_SIZE(hsotg->supplies); i++)
hsotg->supplies[i].supply = dwc2_hsotg_supply_names[i];
ret = devm_regulator_bulk_get(hsotg->dev, ARRAY_SIZE(hsotg->supplies),
hsotg->supplies);
if (ret) {
dev_err(hsotg->dev, "failed to request supplies: %d\n", ret);
return ret;
}
return 0;
}
/**
* dwc2_driver_remove() - Called when the DWC_otg core is unregistered with the
* DWC_otg driver
*
* @dev: Platform device
*
* This routine is called, for example, when the rmmod command is executed. The
* device may or may not be electrically present. If it is present, the driver
* stops device processing. Any resources used on behalf of this device are
* freed.
*/
static int dwc2_driver_remove(struct platform_device *dev)
{
struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
dwc2_debugfs_exit(hsotg);
if (hsotg->hcd_enabled)
dwc2_hcd_remove(hsotg);
if (hsotg->gadget_enabled)
dwc2_hsotg_remove(hsotg);
if (hsotg->ll_hw_enabled)
dwc2_lowlevel_hw_disable(hsotg);
reset_control_assert(hsotg->reset);
reset_control_assert(hsotg->reset_ecc);
return 0;
}
/**
* dwc2_driver_shutdown() - Called on device shutdown
*
* @dev: Platform device
*
* In specific conditions (involving usb hubs) dwc2 devices can create a
* lot of interrupts, even to the point of overwhelming devices running
* at low frequencies. Some devices need to do special clock handling
* at shutdown-time which may bring the system clock below the threshold
* of being able to handle the dwc2 interrupts. Disabling dwc2-irqs
* prevents reboots/poweroffs from getting stuck in such cases.
*/
static void dwc2_driver_shutdown(struct platform_device *dev)
{
struct dwc2_hsotg *hsotg = platform_get_drvdata(dev);
disable_irq(hsotg->irq);
}
/**
* dwc2_driver_probe() - Called when the DWC_otg core is bound to the DWC_otg
* driver
*
* @dev: Platform device
*
* This routine creates the driver components required to control the device
* (core, HCD, and PCD) and initializes the device. The driver components are
* stored in a dwc2_hsotg structure. A reference to the dwc2_hsotg is saved
* in the device private data. This allows the driver to access the dwc2_hsotg
* structure on subsequent calls to driver methods for this device.
*/
static int dwc2_driver_probe(struct platform_device *dev)
{
struct dwc2_hsotg *hsotg;
struct resource *res;
int retval;
hsotg = devm_kzalloc(&dev->dev, sizeof(*hsotg), GFP_KERNEL);
if (!hsotg)
return -ENOMEM;
hsotg->dev = &dev->dev;
/*
* Use reasonable defaults so platforms don't have to provide these.
*/
if (!dev->dev.dma_mask)
dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
retval = dma_set_coherent_mask(&dev->dev, DMA_BIT_MASK(32));
if (retval) {
dev_err(&dev->dev, "can't set coherent DMA mask: %d\n", retval);
return retval;
}
res = platform_get_resource(dev, IORESOURCE_MEM, 0);
hsotg->regs = devm_ioremap_resource(&dev->dev, res);
if (IS_ERR(hsotg->regs))
return PTR_ERR(hsotg->regs);
dev_dbg(&dev->dev, "mapped PA %08lx to VA %p\n",
(unsigned long)res->start, hsotg->regs);
retval = dwc2_lowlevel_hw_init(hsotg);
if (retval)
return retval;
spin_lock_init(&hsotg->lock);
hsotg->irq = platform_get_irq(dev, 0);
if (hsotg->irq < 0) {
dev_err(&dev->dev, "missing IRQ resource\n");
return hsotg->irq;
}
dev_dbg(hsotg->dev, "registering common handler for irq%d\n",
hsotg->irq);
retval = devm_request_irq(hsotg->dev, hsotg->irq,
dwc2_handle_common_intr, IRQF_SHARED,
dev_name(hsotg->dev), hsotg);
if (retval)
return retval;
retval = dwc2_lowlevel_hw_enable(hsotg);
if (retval)
return retval;
retval = dwc2_get_dr_mode(hsotg);
if (retval)
goto error;
/*
* Reset before dwc2_get_hwparams() then it could get power-on real
* reset value form registers.
*/
retval = dwc2_core_reset(hsotg, false);
if (retval)
goto error;
/* Detect config values from hardware */
retval = dwc2_get_hwparams(hsotg);
if (retval)
goto error;
/*
* For OTG cores, set the force mode bits to reflect the value
* of dr_mode. Force mode bits should not be touched at any
* other time after this.
*/
dwc2_force_dr_mode(hsotg);
retval = dwc2_init_params(hsotg);
if (retval)
goto error;
if (hsotg->dr_mode != USB_DR_MODE_HOST) {
retval = dwc2_gadget_init(hsotg);
if (retval)
goto error;
hsotg->gadget_enabled = 1;
}
if (hsotg->dr_mode != USB_DR_MODE_PERIPHERAL) {
retval = dwc2_hcd_init(hsotg);
if (retval) {
if (hsotg->gadget_enabled)
dwc2_hsotg_remove(hsotg);
goto error;
}
hsotg->hcd_enabled = 1;
}
platform_set_drvdata(dev, hsotg);
hsotg->hibernated = 0;
dwc2_debugfs_init(hsotg);
/* Gadget code manages lowlevel hw on its own */
if (hsotg->dr_mode == USB_DR_MODE_PERIPHERAL)
dwc2_lowlevel_hw_disable(hsotg);
return 0;
error:
dwc2_lowlevel_hw_disable(hsotg);
return retval;
}
static int __maybe_unused dwc2_suspend(struct device *dev)
{
struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
int ret = 0;
if (dwc2_is_device_mode(dwc2))
dwc2_hsotg_suspend(dwc2);
if (dwc2->ll_hw_enabled)
ret = __dwc2_lowlevel_hw_disable(dwc2);
return ret;
}
static int __maybe_unused dwc2_resume(struct device *dev)
{
struct dwc2_hsotg *dwc2 = dev_get_drvdata(dev);
int ret = 0;
if (dwc2->ll_hw_enabled) {
ret = __dwc2_lowlevel_hw_enable(dwc2);
if (ret)
return ret;
}
if (dwc2_is_device_mode(dwc2))
ret = dwc2_hsotg_resume(dwc2);
return ret;
}
static const struct dev_pm_ops dwc2_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(dwc2_suspend, dwc2_resume)
};
static struct platform_driver dwc2_platform_driver = {
.driver = {
.name = dwc2_driver_name,
.of_match_table = dwc2_of_match_table,
.pm = &dwc2_dev_pm_ops,
},
.probe = dwc2_driver_probe,
.remove = dwc2_driver_remove,
.shutdown = dwc2_driver_shutdown,
};
module_platform_driver(dwc2_platform_driver);
MODULE_DESCRIPTION("DESIGNWARE HS OTG Platform Glue");
MODULE_AUTHOR("Matthijs Kooijman <matthijs@stdin.nl>");
MODULE_LICENSE("Dual BSD/GPL");
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