[next, PATCH 1/6] usb: mtu3: re-enable controller to accept LPM request after LPM resume

[next, PATCH 1/6] usb: mtu3: re-enable controller to accept LPM request after LPM resume

[Chunfeng Yun]

After the controller receives a LPM request, it will reject the LPM
request, and need software to re-enable it after LPM resume if the
controller doesn't remote wakeup from L1 automatically

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3_core.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/mtu3/mtu3_core.c b/drivers/usb/mtu3/mtu3_core.c
index b1b99a8..65ff53a 100644
--- a/drivers/usb/mtu3/mtu3_core.c
+++ b/drivers/usb/mtu3/mtu3_core.c
@@ -176,7 +176,7 @@ static void mtu3_intr_enable(struct mtu3 *mtu)
 	mtu3_writel(mbase, U3D_LV1IESR, value);
 
 	/* Enable U2 common USB interrupts */
-	value = SUSPEND_INTR | RESUME_INTR | RESET_INTR;
+	value = SUSPEND_INTR | RESUME_INTR | RESET_INTR | LPM_RESUME_INTR;
 	mtu3_writel(mbase, U3D_COMMON_USB_INTR_ENABLE, value);
 
 	if (mtu->is_u3_ip) {
@@ -692,6 +692,12 @@ static irqreturn_t mtu3_u2_common_isr(struct mtu3 *mtu)
 	if (u2comm & RESET_INTR)
 		mtu3_gadget_reset(mtu);
 
+	if (u2comm & LPM_RESUME_INTR) {
+		if (!(mtu3_readl(mbase, U3D_POWER_MANAGEMENT) & LPM_HRWE))
+			mtu3_setbits(mbase, U3D_USB20_MISC_CONTROL,
+				     LPM_U3_ACK_EN);
+	}
+
 	return IRQ_HANDLED;
 }
 
-- 
1.9.1

[next, PATCH 2/6] usb: mtu3: fix uncontinuous SeqN issue after disable EP

[Chunfeng Yun]

Reset EP when disable it to reset data toggle for U2 EP, and
SeqN, flow control status etc for U3 EP, this can avoid
issue of uncontinuous SeqN

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3_core.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3_core.c b/drivers/usb/mtu3/mtu3_core.c
index 65ff53a..279f9cd 100644
--- a/drivers/usb/mtu3/mtu3_core.c
+++ b/drivers/usb/mtu3/mtu3_core.c
@@ -195,6 +195,16 @@ static void mtu3_intr_enable(struct mtu3 *mtu)
 	mtu3_writel(mbase, U3D_DEV_LINK_INTR_ENABLE, SSUSB_DEV_SPEED_CHG_INTR);
 }
 
+/* reset: u2 - data toggle, u3 - SeqN, flow control status etc */
+static void mtu3_ep_reset(struct mtu3_ep *mep)
+{
+	struct mtu3 *mtu = mep->mtu;
+	u32 rst_bit = EP_RST(mep->is_in, mep->epnum);
+
+	mtu3_setbits(mtu->mac_base, U3D_EP_RST, rst_bit);
+	mtu3_clrbits(mtu->mac_base, U3D_EP_RST, rst_bit);
+}
+
 /* set/clear the stall and toggle bits for non-ep0 */
 void mtu3_ep_stall_set(struct mtu3_ep *mep, bool set)
 {
@@ -220,8 +230,7 @@ void mtu3_ep_stall_set(struct mtu3_ep *mep, bool set)
 	}
 
 	if (!set) {
-		mtu3_setbits(mbase, U3D_EP_RST, EP_RST(mep->is_in, epnum));
-		mtu3_clrbits(mbase, U3D_EP_RST, EP_RST(mep->is_in, epnum));
+		mtu3_ep_reset(mep);
 		mep->flags &= ~MTU3_EP_STALL;
 	} else {
 		mep->flags |= MTU3_EP_STALL;
@@ -400,6 +409,7 @@ void mtu3_deconfig_ep(struct mtu3 *mtu, struct mtu3_ep *mep)
 		mtu3_setbits(mbase, U3D_QIECR0, QMU_RX_DONE_INT(epnum));
 	}
 
+	mtu3_ep_reset(mep);
 	ep_fifo_free(mep);
 
 	dev_dbg(mtu->dev, "%s: %s\n", __func__, mep->name);
-- 
1.9.1

[next, PATCH 3/6] usb: mtu3: clear test_mode flag when reset

[Chunfeng Yun]

Clear test_mode flag when the gadget is reset by host, otherwise
will affect the next test item.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3_gadget.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/mtu3/mtu3_gadget.c b/drivers/usb/mtu3/mtu3_gadget.c
index de0de01..5c60a8c 100644
--- a/drivers/usb/mtu3/mtu3_gadget.c
+++ b/drivers/usb/mtu3/mtu3_gadget.c
@@ -719,4 +719,5 @@ void mtu3_gadget_reset(struct mtu3 *mtu)
 	mtu->u1_enable = 0;
 	mtu->u2_enable = 0;
 	mtu->delayed_status = false;
+	mtu->test_mode = false;
 }
-- 
1.9.1

[next, PATCH 4/6] usb: mtu3: avoid sleep in atomic context when enter test mode

[Chunfeng Yun]

Use readl_poll_timeout_atomic() instead of readl_poll_timeout()
in atomic context

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3_gadget_ep0.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/mtu3/mtu3_gadget_ep0.c b/drivers/usb/mtu3/mtu3_gadget_ep0.c
index 0d2b1cf..25216e7 100644
--- a/drivers/usb/mtu3/mtu3_gadget_ep0.c
+++ b/drivers/usb/mtu3/mtu3_gadget_ep0.c
@@ -299,7 +299,7 @@ static int handle_test_mode(struct mtu3 *mtu, struct usb_ctrlrequest *setup)
 	mtu3_writel(mbase, U3D_EP0CSR, value | EP0_SETUPPKTRDY | EP0_DATAEND);
 
 	/* wait for ACK status sent by host */
-	readl_poll_timeout(mbase + U3D_EP0CSR, value,
+	readl_poll_timeout_atomic(mbase + U3D_EP0CSR, value,
 			!(value & EP0_DATAEND), 100, 5000);
 
 	mtu3_writel(mbase, U3D_USB2_TEST_MODE, mtu->test_mode_nr);
-- 
1.9.1

[next, PATCH 5/6] usb: mtu3: reset gadget when VBUS_FALL interrupt arises

[Chunfeng Yun]

When VBUS_FALL interrupt arises, it means U3 device is disconnected
with host, so need reset status of gadget

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3_core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/mtu3/mtu3_core.c b/drivers/usb/mtu3/mtu3_core.c
index 279f9cd..eecfd06 100644
--- a/drivers/usb/mtu3/mtu3_core.c
+++ b/drivers/usb/mtu3/mtu3_core.c
@@ -668,8 +668,10 @@ static irqreturn_t mtu3_u3_ltssm_isr(struct mtu3 *mtu)
 	if (ltssm & (HOT_RST_INTR | WARM_RST_INTR))
 		mtu3_gadget_reset(mtu);
 
-	if (ltssm & VBUS_FALL_INTR)
+	if (ltssm & VBUS_FALL_INTR) {
 		mtu3_ss_func_set(mtu, false);
+		mtu3_gadget_reset(mtu);
+	}
 
 	if (ltssm & VBUS_RISE_INTR)
 		mtu3_ss_func_set(mtu, true);
-- 
1.9.1

[next, PATCH 6/6] usb: mtu3: fix warning of sleep in atomic context in notifier callback

[Chunfeng Yun]

The notifier callbacks of extcon are called in atomic context, but the
callbacks will call regulator_enable()/regulator_disable() which may
sleep caused by mutex, so use work queue to call the sleep functions.

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
 drivers/usb/mtu3/mtu3.h    | 11 ++++++++++-
 drivers/usb/mtu3/mtu3_dr.c | 44 ++++++++++++++++++++++++++++++++++++--------
 2 files changed, 46 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3.h b/drivers/usb/mtu3/mtu3.h
index a56fee0..87823ac 100644
--- a/drivers/usb/mtu3/mtu3.h
+++ b/drivers/usb/mtu3/mtu3.h
@@ -196,7 +196,12 @@ struct mtu3_gpd_ring {
 * @vbus: vbus 5V used by host mode
 * @edev: external connector used to detect vbus and iddig changes
 * @vbus_nb: notifier for vbus detection
-* @vbus_nb: notifier for iddig(idpin) detection
+* @vbus_work : work of vbus detection notifier, used to avoid sleep in
+*		notifier callback which is atomic context
+* @vbus_event : event of vbus detecion notifier
+* @id_nb : notifier for iddig(idpin) detection
+* @id_work : work of iddig detection notifier
+* @id_event : event of iddig detecion notifier
 * @is_u3_drd: whether port0 supports usb3.0 dual-role device or not
 * @manual_drd_enabled: it's true when supports dual-role device by debugfs
 *		to switch host/device modes depending on user input.
@@ -205,7 +210,11 @@ struct otg_switch_mtk {
 	struct regulator *vbus;
 	struct extcon_dev *edev;
 	struct notifier_block vbus_nb;
+	struct work_struct vbus_work;
+	unsigned long vbus_event;
 	struct notifier_block id_nb;
+	struct work_struct id_work;
+	unsigned long id_event;
 	bool is_u3_drd;
 	bool manual_drd_enabled;
 };
diff --git a/drivers/usb/mtu3/mtu3_dr.c b/drivers/usb/mtu3/mtu3_dr.c
index 80083e0..8c3bbf7 100644
--- a/drivers/usb/mtu3/mtu3_dr.c
+++ b/drivers/usb/mtu3/mtu3_dr.c
@@ -174,16 +174,40 @@ static void ssusb_set_mailbox(struct otg_switch_mtk *otg_sx,
 	}
 }
 
-static int ssusb_id_notifier(struct notifier_block *nb,
-	unsigned long event, void *ptr)
+static void ssusb_id_work(struct work_struct *work)
 {
 	struct otg_switch_mtk *otg_sx =
-		container_of(nb, struct otg_switch_mtk, id_nb);
+		container_of(work, struct otg_switch_mtk, id_work);
 
-	if (event)
+	if (otg_sx->id_event)
 		ssusb_set_mailbox(otg_sx, MTU3_ID_GROUND);
 	else
 		ssusb_set_mailbox(otg_sx, MTU3_ID_FLOAT);
+}
+
+static void ssusb_vbus_work(struct work_struct *work)
+{
+	struct otg_switch_mtk *otg_sx =
+		container_of(work, struct otg_switch_mtk, vbus_work);
+
+	if (otg_sx->vbus_event)
+		ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID);
+	else
+		ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF);
+}
+
+/*
+ * @ssusb_id_notifier is called in atomic context, but @ssusb_set_mailbox
+ * may sleep, so use work queue here
+ */
+static int ssusb_id_notifier(struct notifier_block *nb,
+	unsigned long event, void *ptr)
+{
+	struct otg_switch_mtk *otg_sx =
+		container_of(nb, struct otg_switch_mtk, id_nb);
+
+	otg_sx->id_event = event;
+	schedule_work(&otg_sx->id_work);
 
 	return NOTIFY_DONE;
 }
@@ -194,10 +218,8 @@ static int ssusb_vbus_notifier(struct notifier_block *nb,
 	struct otg_switch_mtk *otg_sx =
 		container_of(nb, struct otg_switch_mtk, vbus_nb);
 
-	if (event)
-		ssusb_set_mailbox(otg_sx, MTU3_VBUS_VALID);
-	else
-		ssusb_set_mailbox(otg_sx, MTU3_VBUS_OFF);
+	otg_sx->vbus_event = event;
+	schedule_work(&otg_sx->vbus_work);
 
 	return NOTIFY_DONE;
 }
@@ -398,6 +420,9 @@ int ssusb_otg_switch_init(struct ssusb_mtk *ssusb)
 {
 	struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
 
+	INIT_WORK(&otg_sx->id_work, ssusb_id_work);
+	INIT_WORK(&otg_sx->vbus_work, ssusb_vbus_work);
+
 	if (otg_sx->manual_drd_enabled)
 		ssusb_debugfs_init(ssusb);
 	else
@@ -412,4 +437,7 @@ void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb)
 
 	if (otg_sx->manual_drd_enabled)
 		ssusb_debugfs_exit(ssusb);
+
+	cancel_work_sync(&otg_sx->id_work);
+	cancel_work_sync(&otg_sx->vbus_work);
 }
-- 
1.9.1