diff mbox series

[v2,08/10] xhci: Clean up ERST_PTR_MASK inversion

Message ID e81751a0fae84fc042ab422ab47da11ad4e33cdd.1692892942.git.lukas@wunner.de
State New
Headers show
Series Multi-segment Event Ring support for XHCI | expand

Commit Message

Lukas Wunner Aug. 24, 2023, 4:15 p.m. UTC
Mathias notes that the ERST_PTR_MASK macro is named as if it's masking
the Event Ring Dequeue Pointer in the ERDP register, but in actuality
it's masking the inverse.

Invert the macro's value for clarity.

Migrate it to the modern GENMASK_ULL() syntax to avoid u64 casts.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
---
 drivers/usb/host/xhci-mem.c  | 3 +--
 drivers/usb/host/xhci-ring.c | 5 ++---
 drivers/usb/host/xhci.c      | 2 +-
 drivers/usb/host/xhci.h      | 2 +-
 4 files changed, 5 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index d4123e6f2549..b133817ad180 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1952,8 +1952,7 @@  static void xhci_set_hc_event_deq(struct xhci_hcd *xhci, struct xhci_interrupter
 	 */
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 		       "// Write event ring dequeue pointer, preserving EHB bit");
-	xhci_write_64(xhci, ((u64) deq & (u64) ~ERST_PTR_MASK),
-			&ir->ir_set->erst_dequeue);
+	xhci_write_64(xhci, deq & ERST_PTR_MASK, &ir->ir_set->erst_dequeue);
 }
 
 static void xhci_add_in_port(struct xhci_hcd *xhci, unsigned int num_ports,
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index ca8b84816e41..c6a89c483663 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3013,13 +3013,12 @@  static void xhci_update_erst_dequeue(struct xhci_hcd *xhci,
 		 * Per 4.9.4, Software writes to the ERDP register shall
 		 * always advance the Event Ring Dequeue Pointer value.
 		 */
-		if ((temp_64 & (u64) ~ERST_PTR_MASK) ==
-				((u64) deq & (u64) ~ERST_PTR_MASK))
+		if ((temp_64 & ERST_PTR_MASK) == (deq & ERST_PTR_MASK))
 			return;
 
 		/* Update HC event ring dequeue pointer */
 		temp_64 = ir->event_ring->deq_seg->num & ERST_DESI_MASK;
-		temp_64 |= ((u64) deq & (u64) ~ERST_PTR_MASK);
+		temp_64 |= deq & ERST_PTR_MASK;
 	}
 
 	/* Clear the event handler busy flag (RW1C) */
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index e1b1b64a0723..68920cb96044 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -520,7 +520,7 @@  int xhci_run(struct usb_hcd *hcd)
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "xhci_run");
 
 	temp_64 = xhci_read_64(xhci, &ir->ir_set->erst_dequeue);
-	temp_64 &= ~ERST_PTR_MASK;
+	temp_64 &= ERST_PTR_MASK;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"ERST deq = 64'h%0lx", (long unsigned int) temp_64);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index a2ca5e4e0b9f..20744e41e385 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -525,7 +525,7 @@  struct xhci_intr_reg {
  * a work queue (or delayed service routine)?
  */
 #define ERST_EHB		(1 << 3)
-#define ERST_PTR_MASK		(0xf)
+#define ERST_PTR_MASK		(GENMASK_ULL(63, 4))
 
 /**
  * struct xhci_run_regs