usb: gadget: s3c-hsotg: stall ep0 in set_halt function

When s3c_hsotg_ep_sethalt() function is called for ep0 it should be stalled
in the same way that it is in s3c_hsotg_process_control() function, because
SET_HALT for ep0 is delayed response for setup request. Endpoint 0, if
halted, it doesn't need CLEAR_HALT because it clears "stalled" state
automatically when next setup request is received.

For this reason this patch moves code setting ep0 to "stalled" state to new
function named s3c_hsotg_stall_ep0() which is called in
s3c_hsotg_process_control() function as an immediate response for setup
request, and in s3c_hsotg_ep_sethalt() function as a delayed response for
setup request.

Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 46 insertions, 32 deletions

diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index 930c490dd83b..99c8e3ca6a3c 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -1186,6 +1186,41 @@ static void s3c_hsotg_enqueue_setup(struct s3c_hsotg *hsotg);
 static void s3c_hsotg_disconnect(struct s3c_hsotg *hsotg);
 
 /**
+ * s3c_hsotg_stall_ep0 - stall ep0
+ * @hsotg: The device state
+ *
+ * Set stall for ep0 as response for setup request.
+ */
+static void s3c_hsotg_stall_ep0(struct s3c_hsotg *hsotg) {
+        struct s3c_hsotg_ep *ep0 = &hsotg->eps[0];
+        u32 reg;
+        u32 ctrl;
+
+        dev_dbg(hsotg->dev, "ep0 stall (dir=%d)\n", ep0->dir_in);
+        reg = (ep0->dir_in) ? DIEPCTL0 : DOEPCTL0;
+
+        /*
+         * DxEPCTL_Stall will be cleared by EP once it has
+         * taken effect, so no need to clear later.
+         */
+
+        ctrl = readl(hsotg->regs + reg);
+        ctrl |= DxEPCTL_Stall;
+        ctrl |= DxEPCTL_CNAK;
+        writel(ctrl, hsotg->regs + reg);
+
+        dev_dbg(hsotg->dev,
+                "written DxEPCTL=0x%08x to %08x (DxEPCTL=0x%08x)\n",
+                ctrl, reg, readl(hsotg->regs + reg));
+
+         /*
+          * complete won't be called, so we enqueue
+          * setup request here
+          */
+         s3c_hsotg_enqueue_setup(hsotg);
+}
+
+/**
  * s3c_hsotg_process_control - process a control request
  * @hsotg: The device state
  * @ctrl: The control request received
@@ -1262,38 +1297,8 @@ static void s3c_hsotg_process_control(struct s3c_hsotg *hsotg,
          * so respond with a STALL for the status stage to indicate failure.
          */
 
-        if (ret < 0) {
-                u32 reg;
-                u32 ctrl;
-
-                dev_dbg(hsotg->dev, "ep0 stall (dir=%d)\n", ep0->dir_in);
-                reg = (ep0->dir_in) ? DIEPCTL0 : DOEPCTL0;
-
-                /*
-                 * DxEPCTL_Stall will be cleared by EP once it has
-                 * taken effect, so no need to clear later.
-                 */
-
-                ctrl = readl(hsotg->regs + reg);
-                ctrl |= DxEPCTL_Stall;
-                ctrl |= DxEPCTL_CNAK;
-                writel(ctrl, hsotg->regs + reg);
-
-                dev_dbg(hsotg->dev,
-                        "written DxEPCTL=0x%08x to %08x (DxEPCTL=0x%08x)\n",
-                        ctrl, reg, readl(hsotg->regs + reg));
-
-                /*
-                 * don't believe we need to anything more to get the EP
-                 * to reply with a STALL packet
-                 */
-
-                 /*
-                  * complete won't be called, so we enqueue
-                  * setup request here
-                  */
-                 s3c_hsotg_enqueue_setup(hsotg);
-        }
+        if (ret < 0)
+                s3c_hsotg_stall_ep0(hsotg);
 }
 
 /**
@@ -2832,6 +2837,15 @@ static int s3c_hsotg_ep_sethalt(struct usb_ep *ep, int value)
 
         dev_info(hs->dev, "%s(ep %p %s, %d)\n", __func__, ep, ep->name, value);
 
+        if (index == 0) {
+                if (value)
+                        s3c_hsotg_stall_ep0(hs);
+                else
+                        dev_warn(hs->dev,
+                                 "%s: can't clear halt on ep0\n", __func__);
+                return 0;
+        }
+
         /* write both IN and OUT control registers */
 
         epreg = DIEPCTL(index);