[U-Boot] [PATCH v2] usbh/ehci: Increase timeout for enumeration

The current logic reads the port status just once after usb_hub_power_on and expects the portstatus and portchange to report the connection status immediately and correctly.
Few pen drives are not able to report both of them immediately ie. those pens report the connection change but not the connected state after the first read. This opportunity once lost is gone for ever because the u-boot, unlike linux or any other OS, works in polling mode.
This patch modifies the logic to read the port status continuously until the portstatus and portchange both report a connection change as well as a connected state or no connection change and no connection. This logic is placed in a timeout of 10 sec. At the end of it, the pen drive would have either reported a ONE or a ZERO in bit 1 of portstatus as well as portchange.
It enhances the set of pen drives which can eventually be detected by u-boot
Signed-off-by: Vipin Kumar vipin.kumar@st.com --- Hello Marek, Igor,
I found another way to handle it. Please let me know if it is OK from the USB stack poit of view. The fact is that a few pens do not report a connected status in portstatus while they report a connection change in portchange after a usb_hub_power_on.
In this patch, I have tried to compare the connection bit from portstatus and portchange for a timeout of 10 seconds. The situation is asumed to be stable once both of them report the same. This seems to have increased the set of pens supported by u-boot without any apparent side effect
Please let me know if this is OK from your side
Regards Vipin
common/usb_hub.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c index e4a1201..3a66b0e 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -396,14 +396,29 @@ static int usb_hub_configure(struct usb_device *dev) for (i = 0; i < dev->maxchild; i++) { ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1); unsigned short portstatus, portchange; + int ret; + ulong start = get_timer(0); + + do { + ret = usb_get_port_status(dev, i + 1, portsts); + if (ret < 0) { + USB_HUB_PRINTF("get_port_status failed\n"); + break; + } + + portstatus = le16_to_cpu(portsts->wPortStatus); + portchange = le16_to_cpu(portsts->wPortChange); + + if ((portchange & USB_PORT_STAT_C_CONNECTION) == + (portstatus & USB_PORT_STAT_CONNECTION)) + break; + + mdelay(100); + } while (get_timer(start) < CONFIG_SYS_HZ * 10);
- if (usb_get_port_status(dev, i + 1, portsts) < 0) { - USB_HUB_PRINTF("get_port_status failed\n"); + if (ret < 0) continue; - }
- portstatus = le16_to_cpu(portsts->wPortStatus); - portchange = le16_to_cpu(portsts->wPortChange); USB_HUB_PRINTF("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);

On 12/07/12 10:58, Vipin Kumar wrote:
The current logic reads the port status just once after usb_hub_power_on and expects the portstatus and portchange to report the connection status immediately and correctly.
Few pen drives are not able to report both of them immediately ie. those pens report the connection change but not the connected state after the first read. This opportunity once lost is gone for ever because the u-boot, unlike linux or any other OS, works in polling mode.
This patch modifies the logic to read the port status continuously until the portstatus and portchange both report a connection change as well as a connected state or no connection change and no connection. This logic is placed in a timeout of 10 sec. At the end of it, the pen drive would have either reported a ONE or a ZERO in bit 1 of portstatus as well as portchange.
It enhances the set of pen drives which can eventually be detected by u-boot
Signed-off-by: Vipin Kumar vipin.kumar@st.com
Hello Marek, Igor,
I found another way to handle it. Please let me know if it is OK from the USB stack poit of view. The fact is that a few pens do not report a connected status in portstatus while they report a connection change in portchange after a usb_hub_power_on.
In this patch, I have tried to compare the connection bit from portstatus and portchange for a timeout of 10 seconds. The situation is asumed to be stable once both of them report the same. This seems to have increased the set of pens supported by u-boot without any apparent side effect
Please let me know if this is OK from your side
Basically, this one looks fine, although I have two minor concerns below.
Regards Vipin
common/usb_hub.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c index e4a1201..3a66b0e 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -396,14 +396,29 @@ static int usb_hub_configure(struct usb_device *dev) for (i = 0; i < dev->maxchild; i++) { ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1); unsigned short portstatus, portchange;
int ret;
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret < 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange & USB_PORT_STAT_C_CONNECTION) ==
(portstatus & USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start) < CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
if (usb_get_port_status(dev, i + 1, portsts) < 0) {
USB_HUB_PRINTF("get_port_status failed\n");
if (ret < 0) continue;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
USB_HUB_PRINTF("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);

On 12/07/12 12:03, Igor Grinberg wrote:
On 12/07/12 10:58, Vipin Kumar wrote:
The current logic reads the port status just once after usb_hub_power_on and expects the portstatus and portchange to report the connection status immediately and correctly.
Few pen drives are not able to report both of them immediately ie. those pens report the connection change but not the connected state after the first read. This opportunity once lost is gone for ever because the u-boot, unlike linux or any other OS, works in polling mode.
This patch modifies the logic to read the port status continuously until the portstatus and portchange both report a connection change as well as a connected state or no connection change and no connection. This logic is placed in a timeout of 10 sec. At the end of it, the pen drive would have either reported a ONE or a ZERO in bit 1 of portstatus as well as portchange.
It enhances the set of pen drives which can eventually be detected by u-boot
Signed-off-by: Vipin Kumar vipin.kumar@st.com
Hello Marek, Igor,
I found another way to handle it. Please let me know if it is OK from the USB stack poit of view. The fact is that a few pens do not report a connected status in portstatus while they report a connection change in portchange after a usb_hub_power_on.
In this patch, I have tried to compare the connection bit from portstatus and portchange for a timeout of 10 seconds. The situation is asumed to be stable once both of them report the same. This seems to have increased the set of pens supported by u-boot without any apparent side effect
Please let me know if this is OK from your side
Basically, this one looks fine, although I have two minor concerns below.
Regards Vipin
common/usb_hub.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c index e4a1201..3a66b0e 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -396,14 +396,29 @@ static int usb_hub_configure(struct usb_device *dev) for (i = 0; i < dev->maxchild; i++) { ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1); unsigned short portstatus, portchange;
int ret;
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret < 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange & USB_PORT_STAT_C_CONNECTION) ==
(portstatus & USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
Never mind, my mistake, USB_PORT_STAT_C_CONNECTION and USB_PORT_STAT_CONNECTION are the same bit in the register.
break;
mdelay(100);
} while (get_timer(start) < CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Once you address this one, feel free to add: Acked-by: Igor Grinberg grinberg@compulab.co.il
if (usb_get_port_status(dev, i + 1, portsts) < 0) {
USB_HUB_PRINTF("get_port_status failed\n");
if (ret < 0) continue;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
USB_HUB_PRINTF("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);

On 12/7/2012 3:48 PM, Igor Grinberg wrote:
On 12/07/12 12:03, Igor Grinberg wrote:
On 12/07/12 10:58, Vipin Kumar wrote:
The current logic reads the port status just once after usb_hub_power_on and expects the portstatus and portchange to report the connection status immediately and correctly.
Few pen drives are not able to report both of them immediately ie. those pens report the connection change but not the connected state after the first read. This opportunity once lost is gone for ever because the u-boot, unlike linux or any other OS, works in polling mode.
This patch modifies the logic to read the port status continuously until the portstatus and portchange both report a connection change as well as a connected state or no connection change and no connection. This logic is placed in a timeout of 10 sec. At the end of it, the pen drive would have either reported a ONE or a ZERO in bit 1 of portstatus as well as portchange.
It enhances the set of pen drives which can eventually be detected by u-boot
Signed-off-by: Vipin Kumarvipin.kumar@st.com
Hello Marek, Igor,
I found another way to handle it. Please let me know if it is OK from the USB stack poit of view. The fact is that a few pens do not report a connected status in portstatus while they report a connection change in portchange after a usb_hub_power_on.
In this patch, I have tried to compare the connection bit from portstatus and portchange for a timeout of 10 seconds. The situation is asumed to be stable once both of them report the same. This seems to have increased the set of pens supported by u-boot without any apparent side effect
Please let me know if this is OK from your side
Basically, this one looks fine, although I have two minor concerns below.
Regards Vipin
common/usb_hub.c | 25 ++++++++++++++++++++----- 1 file changed, 20 insertions(+), 5 deletions(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c index e4a1201..3a66b0e 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -396,14 +396,29 @@ static int usb_hub_configure(struct usb_device *dev) for (i = 0; i< dev->maxchild; i++) { ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1); unsigned short portstatus, portchange;
int ret;
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
Never mind, my mistake, USB_PORT_STAT_C_CONNECTION and USB_PORT_STAT_CONNECTION are the same bit in the register.
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Once you address this one, feel free to add: Acked-by: Igor Grinberggrinberg@compulab.co.il
Thanks Igor, let me wait for Marek's comments also
if (usb_get_port_status(dev, i + 1, portsts)< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
if (ret< 0) continue;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
USB_HUB_PRINTF("Port %d Status %X Change %X\n", i + 1, portstatus, portchange);

ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Not really. Just a practical test. Marek, can I have comments from you as well
Thanks Vipin

Dear Vipin Kumar,
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Not really. Just a practical test. Marek, can I have comments from you as well
Sorry, I'm really busy these days. I went through it and I see Igor still has some comment. Just fix that one and I'm good.
Best regards, Marek Vasut

On 12/12/2012 4:55 PM, Marek Vasut wrote:
Dear Vipin Kumar,
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Not really. Just a practical test. Marek, can I have comments from you as well
Sorry, I'm really busy these days. I went through it and I see Igor still has some comment. Just fix that one and I'm good.
Thanks marek, I would send a v3 soon
Best regards, Marek Vasut .

On 12/12/12 11:54, Vipin Kumar wrote:
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Not really. Just a practical test.
Ok. good. can we please have a comment saying that this value is based on observations? Thanks! You can add my ack along with the comment in v3.
Thanks for the patch!

On 12/12/2012 5:10 PM, Igor Grinberg wrote:
On 12/12/12 11:54, Vipin Kumar wrote:
ulong start = get_timer(0);
do {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret< 0) {
USB_HUB_PRINTF("get_port_status failed\n");
break;
}
portstatus = le16_to_cpu(portsts->wPortStatus);
portchange = le16_to_cpu(portsts->wPortChange);
if ((portchange& USB_PORT_STAT_C_CONNECTION) ==
(portstatus& USB_PORT_STAT_CONNECTION))
I don't know if there is any corner case when the above check will always fail and so it will always wait a maximal delay time. Are those registers that identical, or can there be differences?
break;
mdelay(100);
} while (get_timer(start)< CONFIG_SYS_HZ * 10);
Is there any justification for the CONFIG_SYS_HZ * 10? I would be much more fine with this patch if there were any (even just test based * 2) reason for that number.
Not really. Just a practical test.
Ok. good. can we please have a comment saying that this value is based on observations? Thanks! You can add my ack along with the comment in v3.
Thanks for the patch!
Thanks Igor Marek, I am waiting for your comments now, if any
-Vipin
participants (3)
-
Igor Grinberg
-
Marek Vasut
-
Vipin Kumar