ENGR00320439-4 usb: chipidea: host: save and restore for host power lost

This patch adds interfaces in role driver to prepare and restore state
for power lost in system sleep. For host experienced power lost,
we can save required resgisters value before suspend; and restore them
after resume.

Signed-off-by: Li Jun <b47624@freescale.com>

2 files changed, 60 insertions, 0 deletions

diff --git a/drivers/usb/chipidea/ci.h b/drivers/usb/chipidea/ci.h
index 47d81a14c025..aabbc4633714 100644
--- a/drivers/usb/chipidea/ci.h
+++ b/drivers/usb/chipidea/ci.h
@@ -79,6 +79,10 @@ struct ci_role_driver {
 	int		(*start)(struct ci_hdrc *);
 	void		(*stop)(struct ci_hdrc *);
 	irqreturn_t	(*irq)(struct ci_hdrc *);
+			/* Save before suspend */
+	void		(*save)(struct ci_hdrc *);
+			/* Restore after power lost */
+	void		(*restore)(struct ci_hdrc *);
 	const char	*name;
 };
 
@@ -190,6 +194,16 @@ struct ci_hdrc {
 	bool				in_lpm;
 	bool				wakeup_int;
 	struct timer_list		timer;
+	/* register save area for suspend&resume */
+	u32				pm_command;
+	u32				pm_status;
+	u32				pm_intr_enable;
+	u32				pm_frame_index;
+	u32				pm_segment;
+	u32				pm_frame_list;
+	u32				pm_async_next;
+	u32				pm_configured_flag;
+	u32				pm_portsc;
 };
 
 static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)
diff --git a/drivers/usb/chipidea/host.c b/drivers/usb/chipidea/host.c
index e073462c487c..b14810a940f2 100644
--- a/drivers/usb/chipidea/host.c
+++ b/drivers/usb/chipidea/host.c
@@ -339,6 +339,50 @@ bool ci_hdrc_host_has_device(struct ci_hdrc *ci)
 	return false;
 }
 
+void ci_hdrc_host_save_for_power_lost(struct ci_hdrc *ci)
+{
+	struct ehci_hcd *ehci = hcd_to_ehci(ci->hcd);
+
+	/* save EHCI registers */
+	ci->pm_command = ehci_readl(ehci, &ehci->regs->command);
+	ci->pm_command &= ~CMD_RUN;
+	ci->pm_status  = ehci_readl(ehci, &ehci->regs->status);
+	ci->pm_intr_enable  = ehci_readl(ehci, &ehci->regs->intr_enable);
+	ci->pm_frame_index  = ehci_readl(ehci, &ehci->regs->frame_index);
+	ci->pm_segment  = ehci_readl(ehci, &ehci->regs->segment);
+	ci->pm_frame_list  = ehci_readl(ehci, &ehci->regs->frame_list);
+	ci->pm_async_next  = ehci_readl(ehci, &ehci->regs->async_next);
+	ci->pm_configured_flag  =
+			ehci_readl(ehci, &ehci->regs->configured_flag);
+	ci->pm_portsc = ehci_readl(ehci, &ehci->regs->port_status[0]);
+}
+
+void ci_hdrc_host_restore_from_power_lost(struct ci_hdrc *ci)
+{
+	struct ehci_hcd *ehci = hcd_to_ehci(ci->hcd);
+	unsigned long   flags;
+	u32 tmp;
+
+	hw_device_reset(ci, USBMODE_CM_HC);
+
+	spin_lock_irqsave(&ehci->lock, flags);
+	/* restore EHCI registers */
+	ehci_writel(ehci, ci->pm_portsc, &ehci->regs->port_status[0]);
+	ehci_writel(ehci, ci->pm_command, &ehci->regs->command);
+	ehci_writel(ehci, ci->pm_intr_enable, &ehci->regs->intr_enable);
+	ehci_writel(ehci, ci->pm_frame_index, &ehci->regs->frame_index);
+	ehci_writel(ehci, ci->pm_segment, &ehci->regs->segment);
+	ehci_writel(ehci, ci->pm_frame_list, &ehci->regs->frame_list);
+	ehci_writel(ehci, ci->pm_async_next, &ehci->regs->async_next);
+	ehci_writel(ehci, ci->pm_configured_flag,
+					&ehci->regs->configured_flag);
+
+	tmp = ehci_readl(ehci, &ehci->regs->command);
+	tmp |= CMD_RUN;
+	ehci_writel(ehci, tmp, &ehci->regs->command);
+	spin_unlock_irqrestore(&ehci->lock, flags);
+}
+
 void ci_hdrc_host_destroy(struct ci_hdrc *ci)
 {
 	if (ci->role == CI_ROLE_HOST && ci->hcd)
@@ -359,6 +403,8 @@ int ci_hdrc_host_init(struct ci_hdrc *ci)
 	rdrv->start	= host_start;
 	rdrv->stop	= host_stop;
 	rdrv->irq	= host_irq;
+	rdrv->save = ci_hdrc_host_save_for_power_lost;
+	rdrv->restore = ci_hdrc_host_restore_from_power_lost;
 	rdrv->name	= "host";
 	ci->roles[CI_ROLE_HOST] = rdrv;