This patch adds few fixes:
- In s3c_hsotg_write_fifo function PTxFEmp/NPTxFEmp interrupts are enabled
  only in shared-fifo mode. In dedicated-fifo mode they should not be used
  (when enabled then cause interrupt storm).
- When s3c_hsotg_trytx is called for ep without enqueued request, interrupts
  for this ep are disabled, to prevent interrupt flooding. Interrupts are
  enabled when new request for this ep is starting.
- In s3c_hsotg_core_init enabled INTknTXFEmpMsk, becouse without this mask
  TxFIFOEmpty interrupt does not occur.
- In OEPInt/IEPInt interrupts handling added bitwise and of DAINT and
  DAINTMSK, because we should handle masked interrupts only.

Signed-off-by: Robert Baldyga <r.bald...@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.p...@samsung.com>
---
 drivers/usb/gadget/s3c-hsotg.c |   48 ++++++++++++++++++++++++++++------------
 1 file changed, 34 insertions(+), 14 deletions(-)

diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index c581cd7..4fb2199 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -553,9 +553,11 @@ static int s3c_hsotg_write_fifo(struct s3c_hsotg *hsotg,
        if (to_write > hs_ep->ep.maxpacket) {
                to_write = hs_ep->ep.maxpacket;
 
-               s3c_hsotg_en_gsint(hsotg,
-                                  periodic ? GINTSTS_PTxFEmp :
-                                  GINTSTS_NPTxFEmp);
+               /* it's needed only when we do not use dedicated fifos */
+               if (!hsotg->dedicated_fifos)
+                       s3c_hsotg_en_gsint(hsotg,
+                                          periodic ? GINTSTS_PTxFEmp :
+                                          GINTSTS_NPTxFEmp);
        }
 
        /* see if we can write data */
@@ -580,9 +582,11 @@ static int s3c_hsotg_write_fifo(struct s3c_hsotg *hsotg,
                 * is more room left.
                 */
 
-               s3c_hsotg_en_gsint(hsotg,
-                                  periodic ? GINTSTS_PTxFEmp :
-                                  GINTSTS_NPTxFEmp);
+               /* it's needed only when we do not use dedicated fifos */
+               if (!hsotg->dedicated_fifos)
+                       s3c_hsotg_en_gsint(hsotg,
+                                          periodic ? GINTSTS_PTxFEmp :
+                                          GINTSTS_NPTxFEmp);
        }
 
        dev_dbg(hsotg->dev, "write %d/%d, can_write %d, done %d\n",
@@ -819,6 +823,9 @@ static void s3c_hsotg_start_req(struct s3c_hsotg *hsotg,
 
        dev_dbg(hsotg->dev, "%s: DxEPCTL=0x%08x\n",
                __func__, readl(hsotg->regs + epctrl_reg));
+
+       /* enable ep interrupts */
+       s3c_hsotg_ctrl_epint(hsotg, hs_ep->index, hs_ep->dir_in, 1);
 }
 
 /**
@@ -1784,8 +1791,15 @@ static int s3c_hsotg_trytx(struct s3c_hsotg *hsotg,
 {
        struct s3c_hsotg_req *hs_req = hs_ep->req;
 
-       if (!hs_ep->dir_in || !hs_req)
+       if (!hs_ep->dir_in || !hs_req) {
+               /**
+                * if request is not enqueued, we disable interrupts for 
endpoints,
+                * excepting ep0
+                */
+               if (hs_ep->index != 0)
+                       s3c_hsotg_ctrl_epint(hsotg, hs_ep->index, 
hs_ep->dir_in, 0);
                return 0;
+       }
 
        if (hs_req->req.actual < hs_req->req.length) {
                dev_dbg(hsotg->dev, "trying to write more for ep%d\n",
@@ -2243,15 +2257,17 @@ static void s3c_hsotg_core_init(struct s3c_hsotg *hsotg)
                       GAHBCFG_HBstLen_Incr4,
                       hsotg->regs + GAHBCFG);
        else
-               writel(GAHBCFG_GlblIntrEn, hsotg->regs + GAHBCFG);
+               writel(GAHBCFG_GlblIntrEn | GAHBCFG_NPTxFEmpLvl,
+                      hsotg->regs + GAHBCFG);
 
        /*
-        * Enabling INTknTXFEmpMsk here seems to be a big mistake, we end
-        * up being flooded with interrupts if the host is polling the
-        * endpoint to try and read data.
+        * If INTknTXFEmpMsk is enabled, it's important to disable ep interrupts
+        * when we have no data to transfer. Otherwise we get being flooded by
+        * interrupts.
         */
 
-       writel(((hsotg->dedicated_fifos) ? DIEPMSK_TxFIFOEmpty : 0) |
+       writel(((hsotg->dedicated_fifos) ? DIEPMSK_TxFIFOEmpty |
+              DIEPMSK_INTknTXFEmpMsk : 0) |
               DIEPMSK_EPDisbldMsk | DIEPMSK_XferComplMsk |
               DIEPMSK_TimeOUTMsk | DIEPMSK_AHBErrMsk |
               DIEPMSK_INTknEPMisMsk,
@@ -2380,10 +2396,14 @@ irq_retry:
 
        if (gintsts & (GINTSTS_OEPInt | GINTSTS_IEPInt)) {
                u32 daint = readl(hsotg->regs + DAINT);
-               u32 daint_out = daint >> DAINT_OutEP_SHIFT;
-               u32 daint_in = daint & ~(daint_out << DAINT_OutEP_SHIFT);
+               u32 daintmsk = readl(hsotg->regs + DAINTMSK);
+               u32 daint_out, daint_in;
                int ep;
 
+               daint &= daintmsk;
+               daint_out = daint >> DAINT_OutEP_SHIFT;
+               daint_in = daint & ~(daint_out << DAINT_OutEP_SHIFT);
+
                dev_dbg(hsotg->dev, "%s: daint=%08x\n", __func__, daint);
 
                for (ep = 0; ep < 15 && daint_out; ep++, daint_out >>= 1) {
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to