usb: dwc3: Support EBC feature of DWC_usb31

Support configuration and use of bulk endpoints in the so-called EBC
mode described in the DBC_usb31 databook (appendix E)

Added a bit fifo_mode to usb_ep to indicate to the UDC driver that a
specific endpoint is to operate in the EBC (or equivalent) mode when
enabled

Added macros for bits 15 and 14 of DEPCFG parameter 1 to indicate EBC
mode and write back behaviour. These bits will be set to 1 when
configuring an EBC endpoint as described in the programming guide

Signed-off-by: Manan Aurora <maurora@google.com>
Link: https://lore.kernel.org/r/20231031034641.660606-1-maurora@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index e120611a5174f7589ac124641a7b279654babff6..e3eea965e57bfd3d32fa6b1cb52fd4072734a30d 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -376,6 +376,7 @@
 /* Global HWPARAMS4 Register */
 #define DWC3_GHWPARAMS4_HIBER_SCRATCHBUFS(n)   (((n) & (0x0f << 13)) >> 13)
 #define DWC3_MAX_HIBER_SCRATCHBUFS             15
+#define DWC3_EXT_BUFF_CONTROL          BIT(21)
 
 /* Global HWPARAMS6 Register */
 #define DWC3_GHWPARAMS6_BCSUPPORT              BIT(14)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 88d8d589f01484b296a47dfcacca88e71921e8e8..c15e965ea95a5d34d2983150917421c49d3b1327 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -673,6 +673,12 @@ static int dwc3_gadget_set_ep_config(struct dwc3_ep *dep, unsigned int action)
                params.param1 |= DWC3_DEPCFG_BINTERVAL_M1(bInterval_m1);
        }
 
+       if (dep->endpoint.fifo_mode) {
+               if (!(dwc->hwparams.hwparams4 & DWC3_EXT_BUFF_CONTROL))
+                       return -EINVAL;
+               params.param1 |= DWC3_DEPCFG_EBC_HWO_NOWB | DWC3_DEPCFG_USE_EBC;
+       }
+
        return dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_SETEPCONFIG, &params);
 }
 

diff --git a/drivers/usb/dwc3/gadget.h b/drivers/usb/dwc3/gadget.h
index 55a56cf67d7364998f9f4a42fd95e5d856cd105c..fd7a4e94397e64ccc74e362e5d73319918fdbae6 100644 (file)
--- a/drivers/usb/dwc3/gadget.h
+++ b/drivers/usb/dwc3/gadget.h
@@ -26,6 +26,8 @@ struct dwc3;
 #define DWC3_DEPCFG_XFER_NOT_READY_EN  BIT(10)
 #define DWC3_DEPCFG_FIFO_ERROR_EN      BIT(11)
 #define DWC3_DEPCFG_STREAM_EVENT_EN    BIT(13)
+#define DWC3_DEPCFG_EBC_HWO_NOWB       BIT(14)
+#define DWC3_DEPCFG_USE_EBC            BIT(15)
 #define DWC3_DEPCFG_BINTERVAL_M1(n)    (((n) & 0xff) << 16)
 #define DWC3_DEPCFG_STREAM_CAPABLE     BIT(24)
 #define DWC3_DEPCFG_EP_NUMBER(n)       (((n) & 0x1f) << 25)

diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 6532beb587b1978e09bc5b17dc088daf91f9f88c..a771ccc038ac949f2b4a835e28d720735e17ee22 100644 (file)
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -236,6 +236,7 @@ struct usb_ep {
        unsigned                max_streams:16;
        unsigned                mult:2;
        unsigned                maxburst:5;
+       unsigned                fifo_mode:1;
        u8                      address;
        const struct usb_endpoint_descriptor    *desc;
        const struct usb_ss_ep_comp_descriptor  *comp_desc;