![Alan Stern](/assets/img/avatar_default.png)
This patch (as1069c) changes the way OHCI root-hub status-change interrupts are enabled. Currently a special HCD method, hub_irq_enable(), is called when the hub driver is finished using a root hub. This approach turns out to be subject to races, resulting in unnecessary polling. The patch does away with the method entirely. Instead, the driver automatically enables the RHSC interrupt when no more status changes are present. This scheme is safe with controllers using level-triggered semantics for their interrupt flags. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
266 lines
6.7 KiB
C
266 lines
6.7 KiB
C
/*
|
|
* OHCI HCD (Host Controller Driver) for USB.
|
|
*
|
|
* (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
|
|
* (C) Copyright 2000-2005 David Brownell
|
|
* (C) Copyright 2002 Hewlett-Packard Company
|
|
* (C) Copyright 2008 Magnus Damm
|
|
*
|
|
* SM501 Bus Glue - based on ohci-omap.c
|
|
*
|
|
* This file is licenced under the GPL.
|
|
*/
|
|
|
|
#include <linux/interrupt.h>
|
|
#include <linux/jiffies.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/dma-mapping.h>
|
|
#include <linux/sm501.h>
|
|
#include <linux/sm501-regs.h>
|
|
|
|
static int ohci_sm501_init(struct usb_hcd *hcd)
|
|
{
|
|
return ohci_init(hcd_to_ohci(hcd));
|
|
}
|
|
|
|
static int ohci_sm501_start(struct usb_hcd *hcd)
|
|
{
|
|
struct device *dev = hcd->self.controller;
|
|
int ret;
|
|
|
|
ret = ohci_run(hcd_to_ohci(hcd));
|
|
if (ret < 0) {
|
|
dev_err(dev, "can't start %s", hcd->self.bus_name);
|
|
ohci_stop(hcd);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static const struct hc_driver ohci_sm501_hc_driver = {
|
|
.description = hcd_name,
|
|
.product_desc = "SM501 OHCI",
|
|
.hcd_priv_size = sizeof(struct ohci_hcd),
|
|
|
|
/*
|
|
* generic hardware linkage
|
|
*/
|
|
.irq = ohci_irq,
|
|
.flags = HCD_USB11 | HCD_MEMORY | HCD_LOCAL_MEM,
|
|
|
|
/*
|
|
* basic lifecycle operations
|
|
*/
|
|
.reset = ohci_sm501_init,
|
|
.start = ohci_sm501_start,
|
|
.stop = ohci_stop,
|
|
.shutdown = ohci_shutdown,
|
|
|
|
/*
|
|
* managing i/o requests and associated device resources
|
|
*/
|
|
.urb_enqueue = ohci_urb_enqueue,
|
|
.urb_dequeue = ohci_urb_dequeue,
|
|
.endpoint_disable = ohci_endpoint_disable,
|
|
|
|
/*
|
|
* scheduling support
|
|
*/
|
|
.get_frame_number = ohci_get_frame,
|
|
|
|
/*
|
|
* root hub support
|
|
*/
|
|
.hub_status_data = ohci_hub_status_data,
|
|
.hub_control = ohci_hub_control,
|
|
#ifdef CONFIG_PM
|
|
.bus_suspend = ohci_bus_suspend,
|
|
.bus_resume = ohci_bus_resume,
|
|
#endif
|
|
.start_port_reset = ohci_start_port_reset,
|
|
};
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
static int ohci_hcd_sm501_drv_probe(struct platform_device *pdev)
|
|
{
|
|
const struct hc_driver *driver = &ohci_sm501_hc_driver;
|
|
struct device *dev = &pdev->dev;
|
|
struct resource *res, *mem;
|
|
int retval, irq;
|
|
struct usb_hcd *hcd = NULL;
|
|
|
|
irq = retval = platform_get_irq(pdev, 0);
|
|
if (retval < 0)
|
|
goto err0;
|
|
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
|
if (mem == NULL) {
|
|
dev_err(dev, "no resource definition for memory\n");
|
|
retval = -ENOENT;
|
|
goto err0;
|
|
}
|
|
|
|
if (!request_mem_region(mem->start, mem->end - mem->start + 1,
|
|
pdev->name)) {
|
|
dev_err(dev, "request_mem_region failed\n");
|
|
retval = -EBUSY;
|
|
goto err0;
|
|
}
|
|
|
|
/* The sm501 chip is equipped with local memory that may be used
|
|
* by on-chip devices such as the video controller and the usb host.
|
|
* This driver uses dma_declare_coherent_memory() to make sure
|
|
* usb allocations with dma_alloc_coherent() allocate from
|
|
* this local memory. The dma_handle returned by dma_alloc_coherent()
|
|
* will be an offset starting from 0 for the first local memory byte.
|
|
*
|
|
* So as long as data is allocated using dma_alloc_coherent() all is
|
|
* fine. This is however not always the case - buffers may be allocated
|
|
* using kmalloc() - so the usb core needs to be told that it must copy
|
|
* data into our local memory if the buffers happen to be placed in
|
|
* regular memory. The HCD_LOCAL_MEM flag does just that.
|
|
*/
|
|
|
|
if (!dma_declare_coherent_memory(dev, mem->start,
|
|
mem->start - mem->parent->start,
|
|
(mem->end - mem->start) + 1,
|
|
DMA_MEMORY_MAP |
|
|
DMA_MEMORY_EXCLUSIVE)) {
|
|
dev_err(dev, "cannot declare coherent memory\n");
|
|
retval = -ENXIO;
|
|
goto err1;
|
|
}
|
|
|
|
/* allocate, reserve and remap resources for registers */
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (res == NULL) {
|
|
dev_err(dev, "no resource definition for registers\n");
|
|
retval = -ENOENT;
|
|
goto err2;
|
|
}
|
|
|
|
hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
|
|
if (!hcd) {
|
|
retval = -ENOMEM;
|
|
goto err2;
|
|
}
|
|
|
|
hcd->rsrc_start = res->start;
|
|
hcd->rsrc_len = res->end - res->start + 1;
|
|
|
|
if (!request_mem_region(hcd->rsrc_start, hcd->rsrc_len, pdev->name)) {
|
|
dev_err(dev, "request_mem_region failed\n");
|
|
retval = -EBUSY;
|
|
goto err3;
|
|
}
|
|
|
|
hcd->regs = ioremap(hcd->rsrc_start, hcd->rsrc_len);
|
|
if (hcd->regs == NULL) {
|
|
dev_err(dev, "cannot remap registers\n");
|
|
retval = -ENXIO;
|
|
goto err4;
|
|
}
|
|
|
|
ohci_hcd_init(hcd_to_ohci(hcd));
|
|
|
|
retval = usb_add_hcd(hcd, irq, IRQF_DISABLED | IRQF_SHARED);
|
|
if (retval)
|
|
goto err4;
|
|
|
|
/* enable power and unmask interrupts */
|
|
|
|
sm501_unit_power(dev->parent, SM501_GATE_USB_HOST, 1);
|
|
sm501_modify_reg(dev->parent, SM501_IRQ_MASK, 1 << 6, 0);
|
|
|
|
return 0;
|
|
err4:
|
|
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
|
|
err3:
|
|
usb_put_hcd(hcd);
|
|
err2:
|
|
dma_release_declared_memory(dev);
|
|
err1:
|
|
release_mem_region(mem->start, mem->end - mem->start + 1);
|
|
err0:
|
|
return retval;
|
|
}
|
|
|
|
static int ohci_hcd_sm501_drv_remove(struct platform_device *pdev)
|
|
{
|
|
struct usb_hcd *hcd = platform_get_drvdata(pdev);
|
|
struct resource *mem;
|
|
|
|
usb_remove_hcd(hcd);
|
|
release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
|
|
usb_put_hcd(hcd);
|
|
dma_release_declared_memory(&pdev->dev);
|
|
mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
|
|
if (mem)
|
|
release_mem_region(mem->start, mem->end - mem->start + 1);
|
|
|
|
/* mask interrupts and disable power */
|
|
|
|
sm501_modify_reg(pdev->dev.parent, SM501_IRQ_MASK, 0, 1 << 6);
|
|
sm501_unit_power(pdev->dev.parent, SM501_GATE_USB_HOST, 0);
|
|
|
|
platform_set_drvdata(pdev, NULL);
|
|
return 0;
|
|
}
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
#ifdef CONFIG_PM
|
|
static int ohci_sm501_suspend(struct platform_device *pdev, pm_message_t msg)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct ohci_hcd *ohci = hcd_to_ohci(platform_get_drvdata(pdev));
|
|
|
|
if (time_before(jiffies, ohci->next_statechange))
|
|
msleep(5);
|
|
ohci->next_statechange = jiffies;
|
|
|
|
sm501_unit_power(dev->parent, SM501_GATE_USB_HOST, 0);
|
|
ohci_to_hcd(ohci)->state = HC_STATE_SUSPENDED;
|
|
return 0;
|
|
}
|
|
|
|
static int ohci_sm501_resume(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct usb_hcd *hcd = platform_get_drvdata(pdev);
|
|
struct ohci_hcd *ohci = hcd_to_ohci(hcd);
|
|
|
|
if (time_before(jiffies, ohci->next_statechange))
|
|
msleep(5);
|
|
ohci->next_statechange = jiffies;
|
|
|
|
sm501_unit_power(dev->parent, SM501_GATE_USB_HOST, 1);
|
|
ohci_finish_controller_resume(hcd);
|
|
return 0;
|
|
}
|
|
#else
|
|
#define ohci_sm501_suspend NULL
|
|
#define ohci_sm501_resume NULL
|
|
#endif
|
|
|
|
/*-------------------------------------------------------------------------*/
|
|
|
|
/*
|
|
* Driver definition to register with the SM501 bus
|
|
*/
|
|
static struct platform_driver ohci_hcd_sm501_driver = {
|
|
.probe = ohci_hcd_sm501_drv_probe,
|
|
.remove = ohci_hcd_sm501_drv_remove,
|
|
.shutdown = usb_hcd_platform_shutdown,
|
|
.suspend = ohci_sm501_suspend,
|
|
.resume = ohci_sm501_resume,
|
|
.driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = "sm501-usb",
|
|
},
|
|
};
|
|
MODULE_ALIAS("platform:sm501-usb");
|