ENGR00134056-2 usb: add low power mode and wakeup support for mx28 otg port

Add low power mode and wakeup support for mx28 otg port,
and the host1 and otg port are fully verified for low power mode and wakeup
function.

Signed-off-by: Peter Chen <peter.chen@freescale.com>

4 files changed, 36 insertions, 7 deletions

diff --git a/drivers/usb/gadget/arcotg_udc.c b/drivers/usb/gadget/arcotg_udc.c
index 987110bc8702..2539c3eb6495 100644
--- a/drivers/usb/gadget/arcotg_udc.c
+++ b/drivers/usb/gadget/arcotg_udc.c
@@ -21,6 +21,7 @@
 #include <linux/errno.h>
 #include <linux/delay.h>
 #include <linux/sched.h>
+#include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/timer.h>
@@ -78,6 +79,7 @@ volatile static struct usb_sys_interface *usb_sys_regs;
 
 /* it is initialized in probe()  */
 static struct fsl_udc *udc_controller;
+static struct workqueue_struct *usb_gadget_queue;
 
 #ifdef POSTPONE_FREE_LAST_DTD
 static struct ep_td_struct *last_free_td;
@@ -109,7 +111,7 @@ extern struct resource *otg_get_resources(void);
 extern void fsl_platform_set_test_mode(struct fsl_usb2_platform_data *pdata, enum usb_test_mode mode);
 
 #ifdef CONFIG_WORKAROUND_ARCUSB_REG_RW
-static void safe_writel(u32 val32, void *addr)
+static void safe_writel(u32 val32, volatile u32 *addr)
 {
 	__asm__ ("swp %0, %0, [%1]" : : "r"(val32), "r"(addr));
 }
@@ -489,6 +491,8 @@ static void dr_controller_run(struct fsl_udc *udc)
 
 	/* enable BSV irq */
 	temp = fsl_readl(&dr_regs->otgsc);
+	/* do not clear otgsc interrupt status */
+	temp &= (~(OTGSC_ID_CHANGE_IRQ_STS | OTGSC_B_SESSION_VALID_IRQ_STS));
 	temp |= OTGSC_B_SESSION_VALID_IRQ_EN;
 	fsl_writel(temp, &dr_regs->otgsc);
 
@@ -496,10 +500,10 @@ static void dr_controller_run(struct fsl_udc *udc)
 	if (!(temp & OTGSC_B_SESSION_VALID)) {
 		/* Set stopped before low power mode */
 		udc->stopped = 1;
-		/* enter lower power mode */
-		dr_phy_low_power_mode(udc, true);
 		/* enable wake up */
 		dr_wake_up_enable(udc, true);
+		/* enter lower power mode */
+		dr_phy_low_power_mode(udc, true);
 		printk(KERN_DEBUG "%s: udc enter low power mode \n", __func__);
 	} else {
 #ifdef CONFIG_ARCH_MX37
@@ -2105,6 +2109,11 @@ static void reset_irq(struct fsl_udc *udc)
 	udc->usb_state = USB_STATE_DEFAULT;
 }
 
+static void fsl_gadget_clk_off_event(struct work_struct *work)
+{
+	dr_clk_gate(false);
+}
+
 /* if wakup udc, return true; else return false*/
 bool try_wake_up_udc(struct fsl_udc *udc)
 {
@@ -2126,6 +2135,10 @@ bool try_wake_up_udc(struct fsl_udc *udc)
 	if (irq_src & OTGSC_B_SESSION_VALID_IRQ_STS) {
 		u32 tmp;
 		fsl_writel(irq_src, &dr_regs->otgsc);
+		/* only handle device interrupt event */
+		if (!(fsl_readl(&dr_regs->otgsc) & OTGSC_STS_USB_ID)) {
+			return false;
+		}
 		tmp = fsl_readl(&dr_regs->usbcmd);
 		/* check BSV bit to see if fall or rise */
 		if (irq_src & OTGSC_B_SESSION_VALID) {
@@ -2143,7 +2156,7 @@ bool try_wake_up_udc(struct fsl_udc *udc)
 			dr_wake_up_enable(udc, true);
 			/* close USB PHY clock */
 			dr_phy_low_power_mode(udc, true);
-			dr_clk_gate(false);
+			queue_work(usb_gadget_queue, &udc->usb_gadget_work);
 			printk(KERN_DEBUG "%s: udc enter low power mode \n", __func__);
 			return false;
 		}
@@ -2931,6 +2944,13 @@ static int __init fsl_udc_probe(struct platform_device *pdev)
 				g_iram_addr + i * g_iram_size;
 		}
 	}
+
+	usb_gadget_queue = create_workqueue("usb_gadget_workqueue");
+	if (usb_gadget_queue == NULL) {
+		printk(KERN_ERR "Coulndn't create usb gadget work queue\n");
+		return -ENOMEM;
+	}
+	INIT_WORK(&udc_controller->usb_gadget_work, fsl_gadget_clk_off_event);
 #ifdef POSTPONE_FREE_LAST_DTD
 	last_free_td = NULL;
 #endif
diff --git a/drivers/usb/gadget/arcotg_udc.h b/drivers/usb/gadget/arcotg_udc.h
index 6f0282b90938..a823a910292d 100644
--- a/drivers/usb/gadget/arcotg_udc.h
+++ b/drivers/usb/gadget/arcotg_udc.h
@@ -623,6 +623,7 @@ struct fsl_udc {
 	struct completion *done;	/* to make sure release() is done */
 	u32 iram_buffer[IRAM_PPH_NTD];
 	void *iram_buffer_v[IRAM_PPH_NTD];
+	struct work_struct 		usb_gadget_work;
 };
 
 /*-------------------------------------------------------------------------*/
diff --git a/drivers/usb/host/ehci-arc.c b/drivers/usb/host/ehci-arc.c
index 81583a09ad51..20416da6d75f 100644
--- a/drivers/usb/host/ehci-arc.c
+++ b/drivers/usb/host/ehci-arc.c
@@ -425,7 +425,8 @@ static int ehci_fsl_bus_resume(struct usb_hcd *hcd)
 			   but the clock opens at wakeup routine
 			 */
 			fsl_usb_clk_gate(hcd->self.controller->platform_data, true);
-		}
+		} else
+			pdata->wakeup_event = 0;
 		usb_host_set_wakeup(hcd->self.controller, false);
 		fsl_usb_lowpower_mode(pdata, false);
 	}
diff --git a/drivers/usb/otg/fsl_otg.c b/drivers/usb/otg/fsl_otg.c
index 2567b042417a..eccd173b33e4 100644
--- a/drivers/usb/otg/fsl_otg.c
+++ b/drivers/usb/otg/fsl_otg.c
@@ -446,12 +446,11 @@ static void fsl_otg_loading_monitor(unsigned long data)
 static void b_session_irq_enable(bool enable)
 {
 	int osc = le32_to_cpu(usb_dr_regs->otgsc);
-	printk(KERN_DEBUG "%s:enable is %d\n", __func__, enable);
+	pr_debug("%s:enable=%d", __func__, enable);
 	/* The other interrupts' status should not be cleared */
 	osc &= ~(OTGSC_INTSTS_USB_ID | OTGSC_INTSTS_A_VBUS_VALID
 		| OTGSC_INTSTS_A_SESSION_VALID | OTGSC_INTSTS_B_SESSION_VALID);
 	osc |= OTGSC_INTSTS_B_SESSION_VALID;
-
 	if (enable)
 		osc |= OTGSC_INTR_B_SESSION_VALID_EN;
 	else
@@ -667,6 +666,14 @@ static int fsl_otg_set_peripheral(struct otg_transceiver *otg_p,
 	if (otg_dev->fsm.id == 1) {
 		fsl_otg_start_host(&otg_dev->fsm, 0);
 		otg_drv_vbus(&otg_dev->fsm, 0);
+		/* Clear OTGSC_INTSTS_B_SESSION_VALID
+		 * When the host driver loads, the vbus may change to 5v for some
+		 * SoC's. But when there is no usb device at host port, the vbus
+		 * will be off, in that case, vbus changes status will be set.
+		 */
+		fsl_otg_clk_gate(true);
+		b_session_irq_enable(false);
+		fsl_otg_clk_gate(false);
 		fsl_otg_start_gadget(&otg_dev->fsm, 1);
 	}