[PATCH 3.16 032/136] usb: renesas_usbhs: gadget: Fix usb_ep_set_{halt,wedge}() behavior

Ben Hutchings
2019-12-17T00:59:26Z

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

commit 4d599cd3a097a85a5c68a2c82b9a48cddf9953ec upstream.

According to usb_ep_set_halt()'s description,
__usbhsg_ep_set_halt_wedge() should return -EAGAIN if the IN endpoint
has any queue or data. Otherwise, this driver is possible to cause
just STALL without sending a short packet data on g_mass_storage driver,
and then a few resetting a device happens on a host side during
a usb enumaration.

Fixes: 2f98382dcdfe ("usb: renesas_usbhs: Add Renesas USBHS Gadget")
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1569924633-322-3-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/renesas_usbhs/common.h | 1 +
drivers/usb/renesas_usbhs/fifo.c | 2 +-
drivers/usb/renesas_usbhs/fifo.h | 1 +
drivers/usb/renesas_usbhs/mod_gadget.c | 16 +++++++++++++++-
drivers/usb/renesas_usbhs/pipe.c | 15 +++++++++++++++
drivers/usb/renesas_usbhs/pipe.h | 1 +
6 files changed, 34 insertions(+), 2 deletions(-)

--- a/drivers/usb/renesas_usbhs/common.h
+++ b/drivers/usb/renesas_usbhs/common.h
@@ -207,6 +207,7 @@ struct usbhs_priv;
/* DCPCTR */
#define BSTS (1 << 15) /* Buffer Status */
#define SUREQ (1 << 14) /* Sending SETUP Token */
+#define INBUFM (1 << 14) /* (PIPEnCTR) Transfer Buffer Monitor */
#define CSSTS (1 << 12) /* CSSTS Status */
#define ACLRM (1 << 9) /* Buffer Auto-Clear Mode */
#define SQCLR (1 << 8) /* Toggle Bit Clear */
--- a/drivers/usb/renesas_usbhs/fifo.c
+++ b/drivers/usb/renesas_usbhs/fifo.c
@@ -100,7 +100,7 @@ static void __usbhsf_pkt_del(struct usbh
list_del_init(&pkt->node);
}

-static struct usbhs_pkt *__usbhsf_pkt_get(struct usbhs_pipe *pipe)
+struct usbhs_pkt *__usbhsf_pkt_get(struct usbhs_pipe *pipe)
{
if (list_empty(&pipe->list))
return NULL;
--- a/drivers/usb/renesas_usbhs/fifo.h
+++ b/drivers/usb/renesas_usbhs/fifo.h
@@ -98,5 +98,6 @@ void usbhs_pkt_push(struct usbhs_pipe *p
void *buf, int len, int zero, int sequence);
struct usbhs_pkt *usbhs_pkt_pop(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt);
void usbhs_pkt_start(struct usbhs_pipe *pipe);
+struct usbhs_pkt *__usbhsf_pkt_get(struct usbhs_pipe *pipe);

#endif /* RENESAS_USB_FIFO_H */
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -704,6 +704,7 @@ static int __usbhsg_ep_set_halt_wedge(st
struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
struct device *dev = usbhsg_gpriv_to_dev(gpriv);
unsigned long flags;
+ int ret = 0;

dev_dbg(dev, "set halt %d (pipe %d)\n",
halt, usbhs_pipe_number(pipe));
@@ -711,6 +712,18 @@ static int __usbhsg_ep_set_halt_wedge(st
/******************** spin lock ********************/
usbhs_lock(priv, flags);

+ /*
+ * According to usb_ep_set_halt()'s description, this function should
+ * return -EAGAIN if the IN endpoint has any queue or data. Note
+ * that the usbhs_pipe_is_dir_in() returns false if the pipe is an
+ * IN endpoint in the gadget mode.
+ */
+ if (!usbhs_pipe_is_dir_in(pipe) && (__usbhsf_pkt_get(pipe) ||
+ usbhs_pipe_contains_transmittable_data(pipe))) {
+ ret = -EAGAIN;
+ goto out;
+ }
+
if (halt)
usbhs_pipe_stall(pipe);
else
@@ -721,10 +734,11 @@ static int __usbhsg_ep_set_halt_wedge(st
else
usbhsg_status_clr(gpriv, USBHSG_STATUS_WEDGE);

+out:
usbhs_unlock(priv, flags);
/******************** spin unlock ******************/

- return 0;
+ return ret;
}

static int usbhsg_ep_set_halt(struct usb_ep *ep, int value)
--- a/drivers/usb/renesas_usbhs/pipe.c
+++ b/drivers/usb/renesas_usbhs/pipe.c
@@ -263,6 +263,21 @@ int usbhs_pipe_is_accessible(struct usbh
return -EBUSY;
}

+bool usbhs_pipe_contains_transmittable_data(struct usbhs_pipe *pipe)
+{
+ u16 val;
+
+ /* Do not support for DCP pipe */
+ if (usbhs_pipe_is_dcp(pipe))
+ return false;
+
+ val = usbhsp_pipectrl_get(pipe);
+ if (val & INBUFM)
+ return true;
+
+ return false;
+}
+
/*
* PID ctrl
*/
--- a/drivers/usb/renesas_usbhs/pipe.h
+++ b/drivers/usb/renesas_usbhs/pipe.h
@@ -85,6 +85,7 @@ void usbhs_pipe_init(struct usbhs_priv *
int usbhs_pipe_get_maxpacket(struct usbhs_pipe *pipe);
void usbhs_pipe_clear(struct usbhs_pipe *pipe);
int usbhs_pipe_is_accessible(struct usbhs_pipe *pipe);
+bool usbhs_pipe_contains_transmittable_data(struct usbhs_pipe *pipe);
void usbhs_pipe_enable(struct usbhs_pipe *pipe);
void usbhs_pipe_disable(struct usbhs_pipe *pipe);
void usbhs_pipe_stall(struct usbhs_pipe *pipe);