usb: Prevent using reserved registers on DM36x usb
The musb driver defines and uses MUSB_CSR0_H_DIS_PING, however this
bit is reserved on the DM36x. Thus this patch ensures that the
reserved bit is not accesssed.
It has been observed that some USB devices will fail to enumerate
with errors such as 'error in inquiry' without this patch.
See http://www.ti.com/litv/pdf/sprufh9a for details.
Cc: Marek Vasut <marex@denx.de>
Cc: Tom Rini <trini@ti.com>
Signed-off-by: Andrew Murray <amurray@embedded-bits.co.uk>
Acked-by: Marek Vasut <marex@denx.de>
diff --git a/drivers/usb/musb/musb_hcd.c b/drivers/usb/musb/musb_hcd.c
index 41a8126..708fa12 100644
--- a/drivers/usb/musb/musb_hcd.c
+++ b/drivers/usb/musb/musb_hcd.c
@@ -417,8 +417,12 @@
/* Set TXPKTRDY bit */
csr = readw(&musbr->txcsr);
- writew(csr | MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY,
- &musbr->txcsr);
+
+ csr |= MUSB_CSR0_TXPKTRDY;
+#if !defined(CONFIG_SOC_DM365)
+ csr |= MUSB_CSR0_H_DIS_PING;
+#endif
+ writew(csr, &musbr->txcsr);
result = wait_until_ep0_ready(dev, MUSB_CSR0_TXPKTRDY);
if (result < 0)
break;
@@ -439,8 +443,10 @@
/* Set the StatusPkt bit */
csr = readw(&musbr->txcsr);
- csr |= (MUSB_CSR0_H_DIS_PING | MUSB_CSR0_TXPKTRDY |
- MUSB_CSR0_H_STATUSPKT);
+ csr |= (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_H_STATUSPKT);
+#if !defined(CONFIG_SOC_DM365)
+ csr |= MUSB_CSR0_H_DIS_PING;
+#endif
writew(csr, &musbr->txcsr);
/* Wait until TXPKTRDY bit is cleared */
@@ -457,7 +463,10 @@
int result;
/* Set the StatusPkt bit and ReqPkt bit */
- csr = MUSB_CSR0_H_DIS_PING | MUSB_CSR0_H_REQPKT | MUSB_CSR0_H_STATUSPKT;
+ csr = MUSB_CSR0_H_REQPKT | MUSB_CSR0_H_STATUSPKT;
+#if !defined(CONFIG_SOC_DM365)
+ csr |= MUSB_CSR0_H_DIS_PING;
+#endif
writew(csr, &musbr->txcsr);
result = wait_until_ep0_ready(dev, MUSB_CSR0_H_REQPKT);