Commit 4f4c5e36 authored by Harro Haan's avatar Harro Haan Committed by Russell King
Browse files

ARM: 5967/1: at91_udc.c use spinlocks instead of local_irq_xxx 

The locking code of this driver is reworked for preempt-rt.

For more info see:
http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20100203/09cdb3b4/attachment.el
http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20100203/3ad44e30/attachment.el

First applied: "at91_udc HW glitch"
http://www.arm.linux.org.uk/developer/patches/viewpatch.php?id=5966/1



Reviewed-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: default avatarHarro Haan <hrhaan@gmail.com>
Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 7e27d6e7

drivers/usb/gadget/at91_udc.c

+93 −46
Original line number Diff line number Diff line
@@ -77,10 +77,10 @@ static const char driver_name [] = "at91_udc"; 
static const char ep0name[] = "ep0";





#define at91_udp_read(dev, reg) \

	__raw_readl((dev)->udp_baseaddr + (reg))

#define at91_udp_write(dev, reg, val) \

	__raw_writel((val), (dev)->udp_baseaddr + (reg))

#define at91_udp_read(udc, reg) \

	__raw_readl((udc)->udp_baseaddr + (reg))

#define at91_udp_write(udc, reg, val) \

	__raw_writel((val), (udc)->udp_baseaddr + (reg))



/*-------------------------------------------------------------------------*/
@@ -102,8 +102,9 @@ static void proc_ep_show(struct seq_file *s, struct at91_ep *ep) 
	u32			csr;

	struct at91_request	*req;

	unsigned long	flags;

	struct at91_udc	*udc = ep->udc;



	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	csr = __raw_readl(ep->creg);
@@ -147,7 +148,7 @@ static void proc_ep_show(struct seq_file *s, struct at91_ep *ep) 
				&req->req, length,

				req->req.length, req->req.buf);

	}

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

}



static void proc_irq_show(struct seq_file *s, const char *label, u32 mask)
@@ -272,7 +273,9 @@ static void done(struct at91_ep *ep, struct at91_request *req, int status) 
		VDBG("%s done %p, status %d\n", ep->ep.name, req, status);



	ep->stopped = 1;

	spin_unlock(&udc->lock);

	req->req.complete(&ep->ep, &req->req);

	spin_lock(&udc->lock);

	ep->stopped = stopped;



	/* ep0 is always ready; other endpoints need a non-empty queue */
@@ -472,7 +475,7 @@ static int at91_ep_enable(struct usb_ep *_ep, 
				const struct usb_endpoint_descriptor *desc)

{

	struct at91_ep	*ep = container_of(_ep, struct at91_ep, ep);

	struct at91_udc	*dev = ep->udc;

	struct at91_udc	*udc = ep->udc;

	u16		maxpacket;

	u32		tmp;

	unsigned long	flags;
@@ -487,7 +490,7 @@ static int at91_ep_enable(struct usb_ep *_ep, 
		return -EINVAL;

	}



	if (!dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {

	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {

		DBG("bogus device state\n");

		return -ESHUTDOWN;

	}
@@ -521,7 +524,7 @@ bogus_max: 
	}



ok:

	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	/* initialize endpoint to match this descriptor */

	ep->is_in = usb_endpoint_dir_in(desc);
@@ -540,10 +543,10 @@ ok: 
	 * reset/init endpoint fifo.  NOTE:  leaves fifo_bank alone,

	 * since endpoint resets don't reset hw pingpong state.

	 */

	at91_udp_write(dev, AT91_UDP_RST_EP, ep->int_mask);

	at91_udp_write(dev, AT91_UDP_RST_EP, 0);

	at91_udp_write(udc, AT91_UDP_RST_EP, ep->int_mask);

	at91_udp_write(udc, AT91_UDP_RST_EP, 0);



	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -556,7 +559,7 @@ static int at91_ep_disable (struct usb_ep * _ep) 
	if (ep == &ep->udc->ep[0])

		return -EINVAL;



	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	nuke(ep, -ESHUTDOWN);
@@ -571,7 +574,7 @@ static int at91_ep_disable (struct usb_ep * _ep) 
		__raw_writel(0, ep->creg);

	}



	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -607,7 +610,7 @@ static int at91_ep_queue(struct usb_ep *_ep, 
{

	struct at91_request	*req;

	struct at91_ep		*ep;

	struct at91_udc		*dev;

	struct at91_udc		*udc;

	int			status;

	unsigned long		flags;
@@ -625,9 +628,9 @@ static int at91_ep_queue(struct usb_ep *_ep, 
		return -EINVAL;

	}



	dev = ep->udc;

	udc = ep->udc;



	if (!dev || !dev->driver || dev->gadget.speed == USB_SPEED_UNKNOWN) {

	if (!udc || !udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {

		DBG("invalid device\n");

		return -EINVAL;

	}
@@ -635,7 +638,7 @@ static int at91_ep_queue(struct usb_ep *_ep, 
	_req->status = -EINPROGRESS;

	_req->actual = 0;



	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	/* try to kickstart any empty and idle queue */

	if (list_empty(&ep->queue) && !ep->stopped) {
@@ -653,7 +656,7 @@ static int at91_ep_queue(struct usb_ep *_ep, 
		if (is_ep0) {

			u32	tmp;



			if (!dev->req_pending) {

			if (!udc->req_pending) {

				status = -EINVAL;

				goto done;

			}
@@ -662,11 +665,11 @@ static int at91_ep_queue(struct usb_ep *_ep, 
			 * defer changing CONFG until after the gadget driver

			 * reconfigures the endpoints.

			 */

			if (dev->wait_for_config_ack) {

				tmp = at91_udp_read(dev, AT91_UDP_GLB_STAT);

			if (udc->wait_for_config_ack) {

				tmp = at91_udp_read(udc, AT91_UDP_GLB_STAT);

				tmp ^= AT91_UDP_CONFG;

				VDBG("toggle config\n");

				at91_udp_write(dev, AT91_UDP_GLB_STAT, tmp);

				at91_udp_write(udc, AT91_UDP_GLB_STAT, tmp);

			}

			if (req->req.length == 0) {

ep0_in_status:
@@ -676,7 +679,7 @@ ep0_in_status: 
				tmp &= ~SET_FX;

				tmp |= CLR_FX | AT91_UDP_TXPKTRDY;

				__raw_writel(tmp, ep->creg);

				dev->req_pending = 0;

				udc->req_pending = 0;

				goto done;

			}

		}
@@ -695,10 +698,10 @@ ep0_in_status: 


	if (req && !status) {

		list_add_tail (&req->queue, &ep->queue);

		at91_udp_write(dev, AT91_UDP_IER, ep->int_mask);

		at91_udp_write(udc, AT91_UDP_IER, ep->int_mask);

	}

done:

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return (status < 0) ? status : 0;

}
@@ -706,20 +709,29 @@ static int at91_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req) 
{

	struct at91_ep		*ep;

	struct at91_request	*req;

	unsigned long		flags;

	struct at91_udc		*udc;



	ep = container_of(_ep, struct at91_ep, ep);

	if (!_ep || ep->ep.name == ep0name)

		return -EINVAL;



	udc = ep->udc;



	spin_lock_irqsave(&udc->lock, flags);



	/* make sure it's actually queued on this endpoint */

	list_for_each_entry (req, &ep->queue, queue) {

		if (&req->req == _req)

			break;

	}

	if (&req->req != _req)

	if (&req->req != _req) {

		spin_unlock_irqrestore(&udc->lock, flags);

		return -EINVAL;

	}



	done(ep, req, -ECONNRESET);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -736,7 +748,7 @@ static int at91_ep_set_halt(struct usb_ep *_ep, int value) 
		return -EINVAL;



	creg = ep->creg;

	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	csr = __raw_readl(creg);
@@ -761,7 +773,7 @@ static int at91_ep_set_halt(struct usb_ep *_ep, int value) 
		__raw_writel(csr, creg);

	}



	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return status;

}
@@ -795,7 +807,7 @@ static int at91_wakeup(struct usb_gadget *gadget) 
	unsigned long	flags;



	DBG("%s\n", __func__ );

	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);



	if (!udc->clocked || !udc->suspended)

		goto done;
@@ -809,7 +821,7 @@ static int at91_wakeup(struct usb_gadget *gadget) 
	at91_udp_write(udc, AT91_UDP_GLB_STAT, glbstate);



done:

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return status;

}
@@ -851,8 +863,11 @@ static void stop_activity(struct at91_udc *udc) 
		ep->stopped = 1;

		nuke(ep, -ESHUTDOWN);

	}

	if (driver)

	if (driver) {

		spin_unlock(&udc->lock);

		driver->disconnect(&udc->gadget);

		spin_lock(&udc->lock);

	}



	udc_reinit(udc);

}
@@ -935,13 +950,13 @@ static int at91_vbus_session(struct usb_gadget *gadget, int is_active) 
	unsigned long	flags;



	// VDBG("vbus %s\n", is_active ? "on" : "off");

	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);

	udc->vbus = (is_active != 0);

	if (udc->driver)

		pullup(udc, is_active);

	else

		pullup(udc, 0);

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -950,10 +965,10 @@ static int at91_pullup(struct usb_gadget *gadget, int is_on) 
	struct at91_udc	*udc = to_udc(gadget);

	unsigned long	flags;



	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);

	udc->enabled = is_on = !!is_on;

	pullup(udc, is_on);

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -962,9 +977,9 @@ static int at91_set_selfpowered(struct usb_gadget *gadget, int is_on) 
	struct at91_udc	*udc = to_udc(gadget);

	unsigned long	flags;



	local_irq_save(flags);

	spin_lock_irqsave(&udc->lock, flags);

	udc->selfpowered = (is_on != 0);

	local_irq_restore(flags);

	spin_unlock_irqrestore(&udc->lock, flags);

	return 0;

}
@@ -1226,8 +1241,11 @@ static void handle_setup(struct at91_udc *udc, struct at91_ep *ep, u32 csr) 
#undef w_length



	/* pass request up to the gadget driver */

	if (udc->driver)

	if (udc->driver) {

		spin_unlock(&udc->lock);

		status = udc->driver->setup(&udc->gadget, &pkt.r);

		spin_lock(&udc->lock);

	}

	else

		status = -ENODEV;

	if (status < 0) {
@@ -1378,6 +1396,9 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc) 
	struct at91_udc		*udc = _udc;

	u32			rescans = 5;

	int			disable_clock = 0;

	unsigned long		flags;



	spin_lock_irqsave(&udc->lock, flags);



	if (!udc->clocked) {

		clk_on(udc);
@@ -1433,8 +1454,11 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc) 
			 * and then into standby to avoid drawing more than

			 * 500uA power (2500uA for some high-power configs).

			 */

			if (udc->driver && udc->driver->suspend)

			if (udc->driver && udc->driver->suspend) {

				spin_unlock(&udc->lock);

				udc->driver->suspend(&udc->gadget);

				spin_lock(&udc->lock);

			}



		/* host initiated resume */

		} else if (status & AT91_UDP_RXRSM) {
@@ -1451,8 +1475,11 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc) 
			 * would normally want to switch out of slow clock

			 * mode into normal mode.

			 */

			if (udc->driver && udc->driver->resume)

			if (udc->driver && udc->driver->resume) {

				spin_unlock(&udc->lock);

				udc->driver->resume(&udc->gadget);

				spin_lock(&udc->lock);

			}



		/* endpoint IRQs are cleared by handling them */

		} else {
@@ -1474,6 +1501,8 @@ static irqreturn_t at91_udc_irq (int irq, void *_udc) 
	if (disable_clock)

		clk_off(udc);



	spin_unlock_irqrestore(&udc->lock, flags);



	return IRQ_HANDLED;

}
@@ -1574,6 +1603,7 @@ int usb_gadget_register_driver (struct usb_gadget_driver *driver) 
{

	struct at91_udc	*udc = &controller;

	int		retval;

	unsigned long	flags;



	if (!driver

			|| driver->speed < USB_SPEED_FULL
@@ -1605,9 +1635,9 @@ int usb_gadget_register_driver (struct usb_gadget_driver *driver) 
		return retval;

	}



	local_irq_disable();

	spin_lock_irqsave(&udc->lock, flags);

	pullup(udc, 1);

	local_irq_enable();

	spin_unlock_irqrestore(&udc->lock, flags);



	DBG("bound to %s\n", driver->driver.name);

	return 0;
@@ -1617,15 +1647,16 @@ EXPORT_SYMBOL (usb_gadget_register_driver); 
int usb_gadget_unregister_driver (struct usb_gadget_driver *driver)

{

	struct at91_udc *udc = &controller;

	unsigned long	flags;



	if (!driver || driver != udc->driver || !driver->unbind)

		return -EINVAL;



	local_irq_disable();

	spin_lock_irqsave(&udc->lock, flags);

	udc->enabled = 0;

	at91_udp_write(udc, AT91_UDP_IDR, ~0);

	pullup(udc, 0);

	local_irq_enable();

	spin_unlock_irqrestore(&udc->lock, flags);



	driver->unbind(&udc->gadget);

	udc->gadget.dev.driver = NULL;
@@ -1641,8 +1672,13 @@ EXPORT_SYMBOL (usb_gadget_unregister_driver); 


static void at91udc_shutdown(struct platform_device *dev)

{

	struct at91_udc *udc = platform_get_drvdata(dev);

	unsigned long	flags;



	/* force disconnect on reboot */

	spin_lock_irqsave(&udc->lock, flags);

	pullup(platform_get_drvdata(dev), 0);

	spin_unlock_irqrestore(&udc->lock, flags);

}



static int __init at91udc_probe(struct platform_device *pdev)
@@ -1683,6 +1719,7 @@ static int __init at91udc_probe(struct platform_device *pdev) 
	udc->board = *(struct at91_udc_data *) dev->platform_data;

	udc->pdev = pdev;

	udc->enabled = 0;

	spin_lock_init(&udc->lock);



	/* rm9200 needs manual D+ pullup; off by default */

	if (cpu_is_at91rm9200()) {
@@ -1804,13 +1841,16 @@ static int __exit at91udc_remove(struct platform_device *pdev) 
{

	struct at91_udc *udc = platform_get_drvdata(pdev);

	struct resource *res;

	unsigned long	flags;



	DBG("remove\n");



	if (udc->driver)

		return -EBUSY;



	spin_lock_irqsave(&udc->lock, flags);

	pullup(udc, 0);

	spin_unlock_irqrestore(&udc->lock, flags);



	device_init_wakeup(&pdev->dev, 0);

	remove_debug_file(udc);
@@ -1840,6 +1880,7 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg) 
{

	struct at91_udc *udc = platform_get_drvdata(pdev);

	int		wake = udc->driver && device_may_wakeup(&pdev->dev);

	unsigned long	flags;



	/* Unless we can act normally to the host (letting it wake us up

	 * whenever it has work for us) force disconnect.  Wakeup requires
@@ -1849,8 +1890,10 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg) 
	if ((!udc->suspended && udc->addr)

			|| !wake

			|| at91_suspend_entering_slow_clock()) {

		spin_lock_irqsave(&udc->lock, flags);

		pullup(udc, 0);

		wake = 0;

		spin_unlock_irqrestore(&udc->lock, flags);

	} else

		enable_irq_wake(udc->udp_irq);
@@ -1863,6 +1906,7 @@ static int at91udc_suspend(struct platform_device *pdev, pm_message_t mesg) 
static int at91udc_resume(struct platform_device *pdev)

{

	struct at91_udc *udc = platform_get_drvdata(pdev);

	unsigned long	flags;



	if (udc->board.vbus_pin > 0 && udc->active_suspend)

		disable_irq_wake(udc->board.vbus_pin);
@@ -1870,8 +1914,11 @@ static int at91udc_resume(struct platform_device *pdev) 
	/* maybe reconnect to host; if so, clocks on */

	if (udc->active_suspend)

		disable_irq_wake(udc->udp_irq);

	else

	else {

		spin_lock_irqsave(&udc->lock, flags);

		pullup(udc, 1);

		spin_unlock_irqrestore(&udc->lock, flags);

	}

	return 0;

}

#else

drivers/usb/gadget/at91_udc.h

+1 −0
Original line number Diff line number Diff line
@@ -144,6 +144,7 @@ struct at91_udc { 
	struct proc_dir_entry		*pde;

	void __iomem			*udp_baseaddr;

	int				udp_irq;

	spinlock_t			lock;

};



static inline struct at91_udc *to_udc(struct usb_gadget *g)

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