usb: gadget: s3c-hsotg: add isochronous transfers support

This patch adds isochronous transfer support. It adds few modifications:
- Modify s3c_hsotg_epint() function. Some interrupts are ignored for
  isochronous endpoints, (e.g. INTknTXFEmpMsk) becouse isochronous request is
  always transfered in single transaction, which ends with XferCompl interrupt.
- Add Odd/Even microframe toggle to allow data transfering in each microframe
  in s3c_hsotg_epint() function.
- Fix s3c_hsotg_ep_enable() function by supporting isochronous endpoint type.

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

diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index 424b2ad..961abcd 100644 (file)
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -83,9 +83,11 @@ struct s3c_hsotg_req;
  * @dir_in: Set to true if this endpoint is of the IN direction, which
  *         means that it is sending data to the Host.
  * @index: The index for the endpoint registers.
+ * @interval - Interval for periodic endpoints
  * @name: The name array passed to the USB core.
  * @halted: Set if the endpoint has been halted.
  * @periodic: Set if this is a periodic ep, such as Interrupt
+ * @isochronous: Set if this is a isochronous ep
  * @sent_zlp: Set if we've sent a zero-length packet.
  * @total_data: The total number of data bytes done.
  * @fifo_size: The size of the FIFO (for periodic IN endpoints)
@@ -121,9 +123,11 @@ struct s3c_hsotg_ep {
 
        unsigned char           dir_in;
        unsigned char           index;
+       unsigned char           interval;
 
        unsigned int            halted:1;
        unsigned int            periodic:1;
+       unsigned int            isochronous:1;
        unsigned int            sent_zlp:1;
 
        char                    name[10];
@@ -1886,8 +1890,10 @@ static void s3c_hsotg_epint(struct s3c_hsotg *hsotg, unsigned int idx,
        u32 epctl_reg = dir_in ? DIEPCTL(idx) : DOEPCTL(idx);
        u32 epsiz_reg = dir_in ? DIEPTSIZ(idx) : DOEPTSIZ(idx);
        u32 ints;
+       u32 ctrl;
 
        ints = readl(hsotg->regs + epint_reg);
+       ctrl = readl(hsotg->regs + epctl_reg);
 
        /* Clear endpoint interrupts */
        writel(ints, hsotg->regs + epint_reg);
@@ -1896,6 +1902,14 @@ static void s3c_hsotg_epint(struct s3c_hsotg *hsotg, unsigned int idx,
                __func__, idx, dir_in ? "in" : "out", ints);
 
        if (ints & DxEPINT_XferCompl) {
+               if (hs_ep->isochronous && hs_ep->interval == 1) {
+                       if (ctrl & DxEPCTL_EOFrNum)
+                               ctrl |= DxEPCTL_SetEvenFr;
+                       else
+                               ctrl |= DxEPCTL_SetOddFr;
+                       writel(ctrl, hsotg->regs + epctl_reg);
+               }
+
                dev_dbg(hsotg->dev,
                        "%s: XferCompl: DxEPCTL=0x%08x, DxEPTSIZ=%08x\n",
                        __func__, readl(hsotg->regs + epctl_reg),
@@ -1962,7 +1976,7 @@ static void s3c_hsotg_epint(struct s3c_hsotg *hsotg, unsigned int idx,
        if (ints & DxEPINT_Back2BackSetup)
                dev_dbg(hsotg->dev, "%s: B2BSetup/INEPNakEff\n", __func__);
 
-       if (dir_in) {
+       if (dir_in && !hs_ep->isochronous) {
                /* not sure if this is important, but we'll clear it anyway */
                if (ints & DIEPMSK_INTknTXFEmpMsk) {
                        dev_dbg(hsotg->dev, "%s: ep%d: INTknTXFEmpMsk\n",
@@ -2581,13 +2595,18 @@ static int s3c_hsotg_ep_enable(struct usb_ep *ep,
        s3c_hsotg_set_ep_maxpacket(hsotg, hs_ep->index, mps);
 
        /* default, set to non-periodic */
+       hs_ep->isochronous = 0;
        hs_ep->periodic = 0;
+       hs_ep->interval = desc->bInterval;
 
        switch (desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) {
        case USB_ENDPOINT_XFER_ISOC:
-               dev_err(hsotg->dev, "no current ISOC support\n");
-               ret = -EINVAL;
-               goto out;
+               epctrl |= DxEPCTL_EPType_Iso;
+               epctrl |= DxEPCTL_SetEvenFr;
+               hs_ep->isochronous = 1;
+               if (dir_in)
+                       hs_ep->periodic = 1;
+               break;
 
        case USB_ENDPOINT_XFER_BULK:
                epctrl |= DxEPCTL_EPType_Bulk;