usb: musb: Perform only write access on MUSB_INTRTXE
This is part of the workaround for AM35x advisory Advisory 1.1.20.
The advisory says that the IPSS bridge can't handle 8 & 16 bit read
access. An 16bit read access to MUSB_INTRTXE results in an 32bit read
access which also reads INTRRX and therefore may lose interrupts.
This patch uses a shadow register of MUSB_INTRTXE so we only perform
write access to it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 3df6a76..e9f0fd9 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -740,7 +740,7 @@
csr = musb_readw(epio, MUSB_TXCSR);
/* disable interrupt in case we flush */
- int_txe = musb_readw(mbase, MUSB_INTRTXE);
+ int_txe = musb->intrtxe;
musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
/* general endpoint setup */