usb: dwc2: host: add function to compare frame index

This function allow comparing frame index used for
descriptor list which has 64 entries.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gregory Herrero <gregory.herrero@intel.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/dwc2/hcd.h b/drivers/usb/dwc2/hcd.h
index f105bada2fd13bddb7005a3a36936bd21a4cf5a5..a19837f655c97ef189d7d95f65c93b5cfd32f86a 100644 (file)
--- a/drivers/usb/dwc2/hcd.h
+++ b/drivers/usb/dwc2/hcd.h
@@ -534,6 +534,19 @@ static inline bool dbg_perio(void) { return false; }
 /* Packet size for any kind of endpoint descriptor */
 #define dwc2_max_packet(wmaxpacketsize) ((wmaxpacketsize) & 0x07ff)
 
+/*
+ * Returns true if frame1 index is greater than frame2 index. The comparison
+ * is done modulo FRLISTEN_64_SIZE. This accounts for the rollover of the
+ * frame number when the max index frame number is reached.
+ */
+static inline bool dwc2_frame_idx_num_gt(u16 fr_idx1, u16 fr_idx2)
+{
+       u16 diff = fr_idx1 - fr_idx2;
+       u16 sign = diff & (FRLISTEN_64_SIZE >> 1);
+
+       return diff && !sign;
+}
+
 /*
  * Returns true if frame1 is less than or equal to frame2. The comparison is
  * done modulo HFNUM_MAX_FRNUM. This accounts for the rollover of the