MLK-11340-41 usb: chipidea: add vbus glitch handling

We add vbus glitch handling for both BSV rise and drop interruptes.
If it is a vbus glitch (higher than BSV but cannot reach AVV), ignore it.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Li Jun <b47624@freescale.com>
(cherry picked from commit 827f2fe71e6222882930db7e89460087cb3bce5b)
(cherry picked from commit 4f9cefe4cf4bb093c8c1766409320dc86dd9a596)

1 files changed, 58 insertions, 1 deletions

diff --git a/drivers/usb/chipidea/otg.c b/drivers/usb/chipidea/otg.c
index 8af573d58c41..ddf2622f7425 100644
--- a/drivers/usb/chipidea/otg.c
+++ b/drivers/usb/chipidea/otg.c
@@ -94,6 +94,27 @@ enum ci_role ci_otg_role(struct ci_hdrc *ci)
 	return role;
 }
 
+#define CI_VBUS_CONNECT_TIMEOUT_MS 500
+static int ci_is_vbus_glitch(struct ci_hdrc *ci)
+{
+	/*
+	 * Handling vbus glitch
+	 *
+	 * We only need to consider glitch for without usb connection,
+	 * With usb connection, we consider it as real disconnection.
+	 *
+	 * If the vbus can't higher than AVV in timeout value, we think
+	 * it is a vbus glitch
+	 */
+	if (hw_wait_reg(ci, OP_OTGSC, OTGSC_AVV, OTGSC_AVV,
+			CI_VBUS_CONNECT_TIMEOUT_MS)) {
+		dev_warn(ci->dev, "there is a vbus glitch\n");
+		return 1;
+	}
+
+	return 0;
+}
+
 void ci_handle_vbus_connected(struct ci_hdrc *ci)
 {
 	/*
@@ -104,7 +125,7 @@ void ci_handle_vbus_connected(struct ci_hdrc *ci)
 	if (!ci->is_otg)
 		return;
 
-	if (hw_read_otgsc(ci, OTGSC_BSV))
+	if (hw_read_otgsc(ci, OTGSC_BSV) && !ci_is_vbus_glitch(ci))
 		usb_gadget_vbus_connect(&ci->gadget);
 }
 
@@ -144,6 +165,33 @@ void ci_handle_id_switch(struct ci_hdrc *ci)
 		ci_role_start(ci, role);
 	}
 }
+
+static void ci_handle_vbus_glitch(struct ci_hdrc *ci)
+{
+	bool valid_vbus_change = false;
+
+	if (hw_read_otgsc(ci, OTGSC_BSV)) {
+		if (!ci_is_vbus_glitch(ci)) {
+			if (ci_otg_is_fsm_mode(ci)) {
+				ci->fsm.b_sess_vld = 1;
+				ci->fsm.b_ssend_srp = 0;
+				otg_del_timer(&ci->fsm, B_SSEND_SRP);
+				otg_del_timer(&ci->fsm, B_SRP_FAIL);
+			}
+			valid_vbus_change = true;
+		}
+	} else {
+		if (ci->vbus_active || (ci_otg_is_fsm_mode(ci) &&
+						ci->fsm.b_sess_vld))
+			valid_vbus_change = true;
+	}
+
+	if (valid_vbus_change) {
+		ci->b_sess_valid_event = true;
+		ci_otg_queue_work(ci);
+	}
+}
+
 /**
  * ci_otg_work - perform otg (vbus/id) event handle
  * @work: work struct
@@ -152,6 +200,15 @@ static void ci_otg_work(struct work_struct *work)
 {
 	struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
 
+	if (ci->vbus_glitch_check_event) {
+		ci->vbus_glitch_check_event = false;
+		pm_runtime_get_sync(ci->dev);
+		ci_handle_vbus_glitch(ci);
+		pm_runtime_put_sync(ci->dev);
+		enable_irq(ci->irq);
+		return;
+	}
+
 	if (ci_otg_is_fsm_mode(ci) && !ci_otg_fsm_work(ci)) {
 		enable_irq(ci->irq);
 		return;