[PATCH v4] usb: ehci: handshake CMD_RUN instead of STS_HALT

From: Neal Liu
Date: Fri Sep 10 2021 - 03:36:59 EST


For Aspeed, HCHalted status depends on not only Run/Stop but also
ASS/PSS status.
Handshake CMD_RUN on startup instead.

Signed-off-by: Neal Liu <neal_liu@xxxxxxxxxxxxxx>
Acked-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Tao Ren <rentao.bupt@xxxxxxxxx>
Tested-by: Tao Ren <rentao.bupt@xxxxxxxxx>
---
drivers/usb/host/ehci-hcd.c | 11 ++++++++++-
drivers/usb/host/ehci-platform.c | 6 ++++++
drivers/usb/host/ehci.h | 1 +
3 files changed, 17 insertions(+), 1 deletion(-)

---
Fix STS_HALT handshake failure for Aspeed 2500/2600 platform.

Change since v3:
- Add more description.

Change since v2:
- Use my "real" name for both the Signed-off-by: line and the From: line.

Change since v1:
- Handshake CMD_RUN status on startup instead of easily skip it.
---

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 6bdc6d6bf74d..55f92d25336b 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -634,7 +634,16 @@ static int ehci_run (struct usb_hcd *hcd)
/* Wait until HC become operational */
ehci_readl(ehci, &ehci->regs->command); /* unblock posted writes */
msleep(5);
- rc = ehci_handshake(ehci, &ehci->regs->status, STS_HALT, 0, 100 * 1000);
+
+ /* For Aspeed, STS_HALT also depends on ASS/PSS status.
+ * Check CMD_RUN instead.
+ */
+ if (ehci->is_aspeed)
+ rc = ehci_handshake(ehci, &ehci->regs->command, CMD_RUN,
+ 1, 100 * 1000);
+ else
+ rc = ehci_handshake(ehci, &ehci->regs->status, STS_HALT,
+ 0, 100 * 1000);

up_write(&ehci_cf_port_reset_rwsem);

diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c
index c70f2d0b4aaf..c3dc906274d9 100644
--- a/drivers/usb/host/ehci-platform.c
+++ b/drivers/usb/host/ehci-platform.c
@@ -297,6 +297,12 @@ static int ehci_platform_probe(struct platform_device *dev)
"has-transaction-translator"))
hcd->has_tt = 1;

+ if (of_device_is_compatible(dev->dev.of_node,
+ "aspeed,ast2500-ehci") ||
+ of_device_is_compatible(dev->dev.of_node,
+ "aspeed,ast2600-ehci"))
+ ehci->is_aspeed = 1;
+
if (soc_device_match(quirk_poll_match))
priv->quirk_poll = true;

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 80bb823aa9fe..fdd073cc053b 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -219,6 +219,7 @@ struct ehci_hcd { /* one per controller */
unsigned need_oc_pp_cycle:1; /* MPC834X port power */
unsigned imx28_write_fix:1; /* For Freescale i.MX28 */
unsigned spurious_oc:1;
+ unsigned is_aspeed:1;

/* required for usb32 quirk */
#define OHCI_CTRL_HCFS (3 << 6)
--
2.25.1