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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-08 21:17:20 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-08 21:17:20 -0300
commiteccbe858ce6412b96fc7cb32eb23a3592f64e5f6 (patch)
treeed4f0e52d266bffc68a5b68afcfe69882b917efb /drivers/usb/dwc3/gadget.c
parent0c1ac6822620b9868cfad5b4c2c223c6cd6fbfd8 (diff)
Linux-libre 4.4.4-gnupck-4.4.4-gnu
Diffstat (limited to 'drivers/usb/dwc3/gadget.c')
-rw-r--r--drivers/usb/dwc3/gadget.c70
1 files changed, 52 insertions, 18 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index a58376fd6..69ffe6e8d 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -388,24 +388,66 @@ static void dwc3_free_trb_pool(struct dwc3_ep *dep)
dep->trb_pool_dma = 0;
}
+static int dwc3_gadget_set_xfer_resource(struct dwc3 *dwc, struct dwc3_ep *dep);
+
+/**
+ * dwc3_gadget_start_config - Configure EP resources
+ * @dwc: pointer to our controller context structure
+ * @dep: endpoint that is being enabled
+ *
+ * The assignment of transfer resources cannot perfectly follow the
+ * data book due to the fact that the controller driver does not have
+ * all knowledge of the configuration in advance. It is given this
+ * information piecemeal by the composite gadget framework after every
+ * SET_CONFIGURATION and SET_INTERFACE. Trying to follow the databook
+ * programming model in this scenario can cause errors. For two
+ * reasons:
+ *
+ * 1) The databook says to do DEPSTARTCFG for every SET_CONFIGURATION
+ * and SET_INTERFACE (8.1.5). This is incorrect in the scenario of
+ * multiple interfaces.
+ *
+ * 2) The databook does not mention doing more DEPXFERCFG for new
+ * endpoint on alt setting (8.1.6).
+ *
+ * The following simplified method is used instead:
+ *
+ * All hardware endpoints can be assigned a transfer resource and this
+ * setting will stay persistent until either a core reset or
+ * hibernation. So whenever we do a DEPSTARTCFG(0) we can go ahead and
+ * do DEPXFERCFG for every hardware endpoint as well. We are
+ * guaranteed that there are as many transfer resources as endpoints.
+ *
+ * This function is called for each endpoint when it is being enabled
+ * but is triggered only when called for EP0-out, which always happens
+ * first, and which should only happen in one of the above conditions.
+ */
static int dwc3_gadget_start_config(struct dwc3 *dwc, struct dwc3_ep *dep)
{
struct dwc3_gadget_ep_cmd_params params;
u32 cmd;
+ int i;
+ int ret;
+
+ if (dep->number)
+ return 0;
memset(&params, 0x00, sizeof(params));
+ cmd = DWC3_DEPCMD_DEPSTARTCFG;
- if (dep->number != 1) {
- cmd = DWC3_DEPCMD_DEPSTARTCFG;
- /* XferRscIdx == 0 for ep0 and 2 for the remaining */
- if (dep->number > 1) {
- if (dwc->start_config_issued)
- return 0;
- dwc->start_config_issued = true;
- cmd |= DWC3_DEPCMD_PARAM(2);
- }
+ ret = dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
+ if (ret)
+ return ret;
- return dwc3_send_gadget_ep_cmd(dwc, 0, cmd, &params);
+ for (i = 0; i < DWC3_ENDPOINTS_NUM; i++) {
+ struct dwc3_ep *dep = dwc->eps[i];
+
+ if (!dep)
+ continue;
+
+ ret = dwc3_gadget_set_xfer_resource(dwc, dep);
+ if (ret)
+ return ret;
}
return 0;
@@ -519,10 +561,6 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep,
struct dwc3_trb *trb_st_hw;
struct dwc3_trb *trb_link;
- ret = dwc3_gadget_set_xfer_resource(dwc, dep);
- if (ret)
- return ret;
-
dep->endpoint.desc = desc;
dep->comp_desc = comp_desc;
dep->type = usb_endpoint_type(desc);
@@ -1604,8 +1642,6 @@ static int dwc3_gadget_start(struct usb_gadget *g,
}
dwc3_writel(dwc->regs, DWC3_DCFG, reg);
- dwc->start_config_issued = false;
-
/* Start with SuperSpeed Default */
dwc3_gadget_ep0_desc.wMaxPacketSize = cpu_to_le16(512);
@@ -2202,7 +2238,6 @@ static void dwc3_gadget_disconnect_interrupt(struct dwc3 *dwc)
dwc3_writel(dwc->regs, DWC3_DCTL, reg);
dwc3_disconnect_gadget(dwc);
- dwc->start_config_issued = false;
dwc->gadget.speed = USB_SPEED_UNKNOWN;
dwc->setup_packet_pending = false;
@@ -2253,7 +2288,6 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
dwc3_stop_active_transfers(dwc);
dwc3_clear_stall_all_ep(dwc);
- dwc->start_config_issued = false;
/* Reset device address to zero */
reg = dwc3_readl(dwc->regs, DWC3_DCFG);