Commit 3d9545cc authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

EHCI: maintain the ehci->command value properly 



The ehci-hcd driver is a little haphazard about keeping track of the
state of the USBCMD register.  The ehci->command field is supposed to
hold the register's value (apart from a few special bits) at all
times, but it isn't maintained properly.

This patch (as1543) cleans up the situation.  It keeps ehci->command
up-to-date, and uses that value rather than reading the register from
the hardware whenever possible.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 09091a4d

drivers/usb/host/ehci-dbg.c

+2 −4
Original line number Diff line number Diff line
@@ -1025,10 +1025,8 @@ static ssize_t debug_lpm_write(struct file *file, const char __user *user_buf, 
		if (strict_strtoul(buf + 5, 16, &hird))

			return -EINVAL;

		printk(KERN_INFO "setting hird %s %lu\n", buf + 6, hird);

		temp = ehci_readl(ehci, &ehci->regs->command);

		temp &= ~CMD_HIRD;

		temp |= hird << 24;

		ehci_writel(ehci, temp, &ehci->regs->command);

		ehci->command = (ehci->command & ~CMD_HIRD) | (hird << 24);

		ehci_writel(ehci, ehci->command, &ehci->regs->command);

	} else if (strncmp(buf, "disable", 7) == 0) {

		if (strict_strtoul(buf + 8, 10, &port))

			return -EINVAL;

drivers/usb/host/ehci-hcd.c

+10 −6
Original line number Diff line number Diff line
@@ -226,8 +226,13 @@ static int ehci_halt (struct ehci_hcd *ehci) 
	if ((temp & STS_HALT) != 0)

		return 0;



	/*

	 * This routine gets called during probe before ehci->command

	 * has been initialized, so we can't rely on its value.

	 */

	ehci->command &= ~CMD_RUN;

	temp = ehci_readl(ehci, &ehci->regs->command);

	temp &= ~CMD_RUN;

	temp &= ~(CMD_RUN | CMD_IAAD);

	ehci_writel(ehci, temp, &ehci->regs->command);

	return handshake (ehci, &ehci->regs->status,

			  STS_HALT, STS_HALT, 16 * 125);
@@ -347,6 +352,7 @@ static int ehci_reset (struct ehci_hcd *ehci) 
	if (ehci->debug)

		dbgp_external_startup();



	ehci->command = ehci_readl(ehci, &ehci->regs->command);

	ehci->port_c_suspend = ehci->suspended_ports =

			ehci->resuming_ports = 0;

	return retval;
@@ -363,16 +369,14 @@ static void ehci_quiesce (struct ehci_hcd *ehci) 
#endif



	/* wait for any schedule enables/disables to take effect */

	temp = ehci_readl(ehci, &ehci->regs->command) << 10;

	temp &= STS_ASS | STS_PSS;

	temp = (ehci->command << 10) & (STS_ASS | STS_PSS);

	if (handshake_on_error_set_halt(ehci, &ehci->regs->status,

					STS_ASS | STS_PSS, temp, 16 * 125))

		return;



	/* then disable anything that's still active */

	temp = ehci_readl(ehci, &ehci->regs->command);

	temp &= ~(CMD_ASE | CMD_IAAD | CMD_PSE);

	ehci_writel(ehci, temp, &ehci->regs->command);

	ehci->command &= ~(CMD_ASE | CMD_PSE);

	ehci_writel(ehci, ehci->command, &ehci->regs->command);



	/* hardware can take 16 microframes to turn off ... */

	handshake_on_error_set_halt(ehci, &ehci->regs->status,

drivers/usb/host/ehci-hub.c

+1 −1
Original line number Diff line number Diff line
@@ -233,7 +233,6 @@ static int ehci_bus_suspend (struct usb_hcd *hcd) 
	/* stop schedules, clean any completed work */

	if (ehci->rh_state == EHCI_RH_RUNNING)

		ehci_quiesce (ehci);

	ehci->command = ehci_readl(ehci, &ehci->regs->command);

	ehci_work(ehci);



	/* Unlike other USB host controller types, EHCI doesn't have
@@ -374,6 +373,7 @@ static int ehci_bus_resume (struct usb_hcd *hcd) 
	ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next);



	/* restore CMD_RUN, framelist size, and irq threshold */

	ehci->command |= CMD_RUN;

	ehci_writel(ehci, ehci->command, &ehci->regs->command);

	ehci->rh_state = EHCI_RH_RUNNING;

drivers/usb/host/ehci-q.c

+6 −10
Original line number Diff line number Diff line
@@ -981,14 +981,12 @@ static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh) 
	head = ehci->async;

	timer_action_done (ehci, TIMER_ASYNC_OFF);

	if (!head->qh_next.qh) {

		u32	cmd = ehci_readl(ehci, &ehci->regs->command);



		if (!(cmd & CMD_ASE)) {

		if (!(ehci->command & CMD_ASE)) {

			/* in case a clear of CMD_ASE didn't take yet */

			(void)handshake(ehci, &ehci->regs->status,

					STS_ASS, 0, 150);

			cmd |= CMD_ASE;

			ehci_writel(ehci, cmd, &ehci->regs->command);

			ehci->command |= CMD_ASE;

			ehci_writel(ehci, ehci->command, &ehci->regs->command);

			/* posted write need not be known to HC yet ... */

		}

	}
@@ -1204,7 +1202,6 @@ static void end_unlink_async (struct ehci_hcd *ehci) 


static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh)

{

	int		cmd = ehci_readl(ehci, &ehci->regs->command);

	struct ehci_qh	*prev;



#ifdef DEBUG
@@ -1222,8 +1219,8 @@ static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh) 
		if (ehci->rh_state != EHCI_RH_HALTED

				&& !ehci->reclaim) {

			/* ... and CMD_IAAD clear */

			ehci_writel(ehci, cmd & ~CMD_ASE,

				    &ehci->regs->command);

			ehci->command &= ~CMD_ASE;

			ehci_writel(ehci, ehci->command, &ehci->regs->command);

			wmb ();

			// handshake later, if we need to

			timer_action_done (ehci, TIMER_ASYNC_OFF);
@@ -1253,8 +1250,7 @@ static void start_unlink_async (struct ehci_hcd *ehci, struct ehci_qh *qh) 
		return;

	}



	cmd |= CMD_IAAD;

	ehci_writel(ehci, cmd, &ehci->regs->command);

	ehci_writel(ehci, ehci->command | CMD_IAAD, &ehci->regs->command);

	(void)ehci_readl(ehci, &ehci->regs->command);

	iaa_watchdog_start(ehci);

}

drivers/usb/host/ehci-sched.c

+4 −6
Original line number Diff line number Diff line
@@ -481,7 +481,6 @@ static int tt_no_collision ( 


static int enable_periodic (struct ehci_hcd *ehci)

{

	u32	cmd;

	int	status;



	if (ehci->periodic_sched++)
@@ -497,8 +496,8 @@ static int enable_periodic (struct ehci_hcd *ehci) 
		return status;

	}



	cmd = ehci_readl(ehci, &ehci->regs->command) | CMD_PSE;

	ehci_writel(ehci, cmd, &ehci->regs->command);

	ehci->command |= CMD_PSE;

	ehci_writel(ehci, ehci->command, &ehci->regs->command);

	/* posted write ... PSS happens later */



	/* make sure ehci_work scans these */
@@ -511,7 +510,6 @@ static int enable_periodic (struct ehci_hcd *ehci) 


static int disable_periodic (struct ehci_hcd *ehci)

{

	u32	cmd;

	int	status;



	if (--ehci->periodic_sched)
@@ -537,8 +535,8 @@ static int disable_periodic (struct ehci_hcd *ehci) 
		return status;

	}



	cmd = ehci_readl(ehci, &ehci->regs->command) & ~CMD_PSE;

	ehci_writel(ehci, cmd, &ehci->regs->command);

	ehci->command &= ~CMD_PSE;

	ehci_writel(ehci, ehci->command, &ehci->regs->command);

	/* posted write ... */



	free_cached_lists(ehci);

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