| Message ID | 201103241415.45115.arnd@arndb.de |
|---|---|
| State | New |
| Headers | show |
On 03/24/2011 01:15 PM, Somebody in the thread at some point said: > The documentation for the USB ethernet devices suggests that > only some devices are supposed to use usb0 as the network interface > name instead of eth0. The logic used there, and documented in > Kconfig for CDC is that eth0 will be used when the mac address > is a globally assigned one, but usb0 is used for the locally > managed range that is typically used on point-to-point links. > > Unfortunately, this has caused a lot of pain on the smsc95xx > device that is used on the popular pandaboard without an > EEPROM to store the MAC address, which causes the driver to > call random_ether_address(). > > Obviously, there should be a proper MAC addressed assigned to > the device, and discussions are ongoing about how to solve > this, but this patch at least makes sure that the default > interface naming gets a little saner and matches what the > user can expect based on the documentation, including for > new devices. > > The approach taken here is to flag whether a device might be a > point-to-point link with the new FLAG_PTP setting in the usbnet > driver_info. A driver can set both FLAG_PTP and FLAG_ETHER if > it is not sure (e.g. cdc_ether), or just one of the two. > The usbnet framework only looks at the MAC address for device > naming if both flags are set, otherwise it trusts the flag. > > Signed-off-by: Arnd Bergmann<arnd.bergmann@linaro.org> > Cc: Andy Green<andy.green@linaro.org> > Cc: patches@linaro.org For Panda case at least, Tested-by: Andy Green <andy.green@linaro.org> -Andy
On Thu, 24 Mar 2011, Arnd Bergmann wrote: > The documentation for the USB ethernet devices suggests that > only some devices are supposed to use usb0 as the network interface > name instead of eth0. The logic used there, and documented in > Kconfig for CDC is that eth0 will be used when the mac address > is a globally assigned one, but usb0 is used for the locally > managed range that is typically used on point-to-point links. > > Unfortunately, this has caused a lot of pain on the smsc95xx > device that is used on the popular pandaboard without an > EEPROM to store the MAC address, which causes the driver to > call random_ether_address(). > > Obviously, there should be a proper MAC addressed assigned to > the device, and discussions are ongoing about how to solve > this, but this patch at least makes sure that the default > interface naming gets a little saner and matches what the > user can expect based on the documentation, including for > new devices. > > The approach taken here is to flag whether a device might be a > point-to-point link with the new FLAG_PTP setting in the usbnet > driver_info. A driver can set both FLAG_PTP and FLAG_ETHER if You updated the flag name in the patch but not in the description. > it is not sure (e.g. cdc_ether), or just one of the two. > The usbnet framework only looks at the MAC address for device > naming if both flags are set, otherwise it trusts the flag. Alan Stern
On Thu, Mar 24, 2011 at 2:15 PM, Arnd Bergmann <arnd@arndb.de> wrote: > > The approach taken here is to flag whether a device might be a > point-to-point link with the new FLAG_PTP setting in the usbnet > driver_info. A driver can set both FLAG_PTP and FLAG_ETHER if > it is not sure (e.g. cdc_ether), or just one of the two. > The usbnet framework only looks at the MAC address for device > naming if both flags are set, otherwise it trusts the flag. Should this paragraph above be a clue for the flag name? Sorry for late comment, but having flag called FLAG_POINTTOPOINT is really confusing. ptp, p2p terms are heavily used and will mislead folks. Would it be better to call it something like IGNORE_MAC_ADDRESS if this is the feature you are targeting? /Alexey
On Thursday 24 March 2011, Alexey Orishko wrote: > On Thu, Mar 24, 2011 at 2:15 PM, Arnd Bergmann <arnd@arndb.de> wrote: > > > > > The approach taken here is to flag whether a device might be a > > point-to-point link with the new FLAG_PTP setting in the usbnet > > driver_info. A driver can set both FLAG_PTP and FLAG_ETHER if > > it is not sure (e.g. cdc_ether), or just one of the two. > > > The usbnet framework only looks at the MAC address for device > > naming if both flags are set, otherwise it trusts the flag. > > Should this paragraph above be a clue for the flag name? > Sorry for late comment, but having flag called FLAG_POINTTOPOINT is really > confusing. ptp, p2p terms are heavily used and will mislead folks. > > Would it be better to call it something like IGNORE_MAC_ADDRESS if this is the > feature you are targeting? That would be a different way of looking at it. FLAG_POINTTOPOINT describes what the device is (a USB cable connecting two hosts), and that flag can be used for various things, where the only thing we currently do is the netif naming. FLAG_IGNORE_MAC_ADDRESS as you suggest describes the implementation of the device naming, not why that is done. The intent here was to some something that makes sense next to FLAG_ETHER, FLAG_WWAN and FLAG_WLAN. I think FLAG_POINTTOPOINT describes this best, although I'd also be happy with FLAG_PTP, FLAG_P2P, FLAG_CABLE or FLAG_USBCABLE. Arnd
On Fri, Mar 25, 2011 at 12:57 PM, Arnd Bergmann <arnd@arndb.de> wrote: > > That would be a different way of looking at it. FLAG_POINTTOPOINT > describes what the device is (a USB cable connecting two hosts), and > that flag can be used for various things, where the only thing > we currently do is the netif naming. > For example, cdc_ether and cdc-ncm drivers can be used in different use cases: a) when device terminates the IP traffic or b) where device is a wireless router. In both cases ethernet frames are sent over usb cable and terminated in device (eth header stripped), so it is point-to-point link for ethernet, but looking from IP layer is not p2p link for case b). Please, explain, based on your idea, do we set this flag in both cases or not? Do you want to use the same netif name for both use cases described above? /alexey
On Friday 25 March 2011, Alexey Orishko wrote: > On Fri, Mar 25, 2011 at 12:57 PM, Arnd Bergmann <arnd@arndb.de> wrote: > > > > That would be a different way of looking at it. FLAG_POINTTOPOINT > > describes what the device is (a USB cable connecting two hosts), and > > that flag can be used for various things, where the only thing > > we currently do is the netif naming. > > > > For example, cdc_ether and cdc-ncm drivers can be used in different use cases: > a) when device terminates the IP traffic > or > b) where device is a wireless router. > > In both cases ethernet frames are sent over usb cable and terminated > in device (eth header stripped), so it is point-to-point link for ethernet, but > looking from IP layer is not p2p link for case b). > > Please, explain, based on your idea, do we set this flag in both cases or not? > Do you want to use the same netif name for both use cases described above? > Most importantly, I want to keep the current rules, so that nothing breaks for existing users. For cdc_ether and cdc-ncm devices, my patch always sets both FLAG_ETHER and FLAG_POINTTOPOINT, because the driver has no way to find out which of the two is actually there. The usb-net core driver interprets this as meaning that it has to decide for the name based on something else, and that happens to be the presence of a globally assigned MAC address. I don't think that keying off the MAC address here is a particularly good idea, but that's what the driver has always done. Arnd
diff --git a/drivers/net/usb/cdc_eem.c b/drivers/net/usb/cdc_eem.c index 5f3b976..8f12854 100644 --- a/drivers/net/usb/cdc_eem.c +++ b/drivers/net/usb/cdc_eem.c @@ -340,7 +340,7 @@ next: static const struct driver_info eem_info = { .description = "CDC EEM Device", - .flags = FLAG_ETHER, + .flags = FLAG_ETHER | FLAG_POINTTOPOINT, .bind = eem_bind, .rx_fixup = eem_rx_fixup, .tx_fixup = eem_tx_fixup, diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c index 9a60e41..98b2bbd 100644 --- a/drivers/net/usb/cdc_ether.c +++ b/drivers/net/usb/cdc_ether.c @@ -450,7 +450,7 @@ static int cdc_manage_power(struct usbnet *dev, int on) static const struct driver_info cdc_info = { .description = "CDC Ethernet Device", - .flags = FLAG_ETHER, + .flags = FLAG_ETHER | FLAG_POINTTOPOINT, // .check_connect = cdc_check_connect, .bind = cdc_bind, .unbind = usbnet_cdc_unbind, diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index 7113168..967371f 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -1237,7 +1237,7 @@ static int cdc_ncm_manage_power(struct usbnet *dev, int status) static const struct driver_info cdc_ncm_info = { .description = "CDC NCM", - .flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET, + .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT | FLAG_MULTI_PACKET, .bind = cdc_ncm_bind, .unbind = cdc_ncm_unbind, .check_connect = cdc_ncm_check_connect, diff --git a/drivers/net/usb/cdc_subset.c b/drivers/net/usb/cdc_subset.c index ca39ace..fc5f13d 100644 --- a/drivers/net/usb/cdc_subset.c +++ b/drivers/net/usb/cdc_subset.c @@ -89,6 +89,7 @@ static int always_connected (struct usbnet *dev) static const struct driver_info ali_m5632_info = { .description = "ALi M5632", + .flags = FLAG_POINTTOPOINT, }; #endif @@ -110,6 +111,7 @@ static const struct driver_info ali_m5632_info = { static const struct driver_info an2720_info = { .description = "AnchorChips/Cypress 2720", + .flags = FLAG_POINTTOPOINT, // no reset available! // no check_connect available! @@ -132,6 +134,7 @@ static const struct driver_info an2720_info = { static const struct driver_info belkin_info = { .description = "Belkin, eTEK, or compatible", + .flags = FLAG_POINTTOPOINT, }; #endif /* CONFIG_USB_BELKIN */ @@ -157,6 +160,7 @@ static const struct driver_info belkin_info = { static const struct driver_info epson2888_info = { .description = "Epson USB Device", .check_connect = always_connected, + .flags = FLAG_POINTTOPOINT, .in = 4, .out = 3, }; @@ -173,6 +177,7 @@ static const struct driver_info epson2888_info = { #define HAVE_HARDWARE static const struct driver_info kc2190_info = { .description = "KC Technology KC-190", + .flags = FLAG_POINTTOPOINT, }; #endif /* CONFIG_USB_KC2190 */ @@ -200,16 +205,19 @@ static const struct driver_info kc2190_info = { static const struct driver_info linuxdev_info = { .description = "Linux Device", .check_connect = always_connected, + .flags = FLAG_POINTTOPOINT, }; static const struct driver_info yopy_info = { .description = "Yopy", .check_connect = always_connected, + .flags = FLAG_POINTTOPOINT, }; static const struct driver_info blob_info = { .description = "Boot Loader OBject", .check_connect = always_connected, + .flags = FLAG_POINTTOPOINT, }; #endif /* CONFIG_USB_ARMLINUX */ diff --git a/drivers/net/usb/gl620a.c b/drivers/net/usb/gl620a.c index dcd57c3..c4cfd1d 100644 --- a/drivers/net/usb/gl620a.c +++ b/drivers/net/usb/gl620a.c @@ -193,7 +193,7 @@ static int genelink_bind(struct usbnet *dev, struct usb_interface *intf) static const struct driver_info genelink_info = { .description = "Genesys GeneLink", - .flags = FLAG_FRAMING_GL | FLAG_NO_SETINT, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_GL | FLAG_NO_SETINT, .bind = genelink_bind, .rx_fixup = genelink_rx_fixup, .tx_fixup = genelink_tx_fixup, diff --git a/drivers/net/usb/net1080.c b/drivers/net/usb/net1080.c index ba72a72..01db460 100644 --- a/drivers/net/usb/net1080.c +++ b/drivers/net/usb/net1080.c @@ -560,7 +560,7 @@ static int net1080_bind(struct usbnet *dev, struct usb_interface *intf) static const struct driver_info net1080_info = { .description = "NetChip TurboCONNECT", - .flags = FLAG_FRAMING_NC, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_NC, .bind = net1080_bind, .reset = net1080_reset, .check_connect = net1080_check_connect, diff --git a/drivers/net/usb/plusb.c b/drivers/net/usb/plusb.c index 08ad269..823c537 100644 --- a/drivers/net/usb/plusb.c +++ b/drivers/net/usb/plusb.c @@ -96,7 +96,7 @@ static int pl_reset(struct usbnet *dev) static const struct driver_info prolific_info = { .description = "Prolific PL-2301/PL-2302", - .flags = FLAG_NO_SETINT, + .flags = FLAG_POINTTOPOINT | FLAG_NO_SETINT, /* some PL-2302 versions seem to fail usb_set_interface() */ .reset = pl_reset, }; diff --git a/drivers/net/usb/rndis_host.c b/drivers/net/usb/rndis_host.c index dd8a4ad..5994a25 100644 --- a/drivers/net/usb/rndis_host.c +++ b/drivers/net/usb/rndis_host.c @@ -573,7 +573,7 @@ EXPORT_SYMBOL_GPL(rndis_tx_fixup); static const struct driver_info rndis_info = { .description = "RNDIS device", - .flags = FLAG_ETHER | FLAG_FRAMING_RN | FLAG_NO_SETINT, + .flags = FLAG_ETHER | FLAG_POINTTOPOINT | FLAG_FRAMING_RN | FLAG_NO_SETINT, .bind = rndis_bind, .unbind = rndis_unbind, .status = rndis_status, diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 95c41d5..c5b6cfb 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1376,7 +1376,8 @@ usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod) // else "eth%d" when there's reasonable doubt. userspace // can rename the link if it knows better. if ((dev->driver_info->flags & FLAG_ETHER) != 0 && - (net->dev_addr [0] & 0x02) == 0) + ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 || + (net->dev_addr [0] & 0x02) == 0)) strcpy (net->name, "eth%d"); /* WLAN devices should always be named "wlan%d" */ if ((dev->driver_info->flags & FLAG_WLAN) != 0) diff --git a/drivers/net/usb/zaurus.c b/drivers/net/usb/zaurus.c index 3eb0b16..241756e 100644 --- a/drivers/net/usb/zaurus.c +++ b/drivers/net/usb/zaurus.c @@ -102,7 +102,7 @@ static int always_connected (struct usbnet *dev) static const struct driver_info zaurus_sl5x00_info = { .description = "Sharp Zaurus SL-5x00", - .flags = FLAG_FRAMING_Z, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_Z, .check_connect = always_connected, .bind = zaurus_bind, .unbind = usbnet_cdc_unbind, @@ -112,7 +112,7 @@ static const struct driver_info zaurus_sl5x00_info = { static const struct driver_info zaurus_pxa_info = { .description = "Sharp Zaurus, PXA-2xx based", - .flags = FLAG_FRAMING_Z, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_Z, .check_connect = always_connected, .bind = zaurus_bind, .unbind = usbnet_cdc_unbind, @@ -122,7 +122,7 @@ static const struct driver_info zaurus_pxa_info = { static const struct driver_info olympus_mxl_info = { .description = "Olympus R1000", - .flags = FLAG_FRAMING_Z, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_Z, .check_connect = always_connected, .bind = zaurus_bind, .unbind = usbnet_cdc_unbind, @@ -258,7 +258,7 @@ bad_desc: static const struct driver_info bogus_mdlm_info = { .description = "pseudo-MDLM (BLAN) device", - .flags = FLAG_FRAMING_Z, + .flags = FLAG_POINTTOPOINT | FLAG_FRAMING_Z, .check_connect = always_connected, .tx_fixup = zaurus_tx_fixup, .bind = blan_mdlm_bind, diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h index 44842c8..1ef9aa0 100644 --- a/include/linux/usb/usbnet.h +++ b/include/linux/usb/usbnet.h @@ -97,6 +97,8 @@ struct driver_info { #define FLAG_LINK_INTR 0x0800 /* updates link (carrier) status */ +#define FLAG_POINTTOPOINT 0x1000 /* possibly use "usb%d" names */ + /* * Indicates to usbnet, that USB driver accumulates multiple IP packets. * Affects statistic (counters) and short packet handling.
The documentation for the USB ethernet devices suggests that only some devices are supposed to use usb0 as the network interface name instead of eth0. The logic used there, and documented in Kconfig for CDC is that eth0 will be used when the mac address is a globally assigned one, but usb0 is used for the locally managed range that is typically used on point-to-point links. Unfortunately, this has caused a lot of pain on the smsc95xx device that is used on the popular pandaboard without an EEPROM to store the MAC address, which causes the driver to call random_ether_address(). Obviously, there should be a proper MAC addressed assigned to the device, and discussions are ongoing about how to solve this, but this patch at least makes sure that the default interface naming gets a little saner and matches what the user can expect based on the documentation, including for new devices. The approach taken here is to flag whether a device might be a point-to-point link with the new FLAG_PTP setting in the usbnet driver_info. A driver can set both FLAG_PTP and FLAG_ETHER if it is not sure (e.g. cdc_ether), or just one of the two. The usbnet framework only looks at the MAC address for device naming if both flags are set, otherwise it trusts the flag. Signed-off-by: Arnd Bergmann <arnd.bergmann@linaro.org> Cc: Andy Green <andy.green@linaro.org> Cc: patches@linaro.org --- drivers/net/usb/cdc_eem.c | 2 +- drivers/net/usb/cdc_ether.c | 2 +- drivers/net/usb/cdc_ncm.c | 2 +- drivers/net/usb/cdc_subset.c | 8 ++++++++ drivers/net/usb/gl620a.c | 2 +- drivers/net/usb/net1080.c | 2 +- drivers/net/usb/plusb.c | 2 +- drivers/net/usb/rndis_host.c | 2 +- drivers/net/usb/usbnet.c | 3 ++- drivers/net/usb/zaurus.c | 8 ++++---- include/linux/usb/usbnet.h | 2 ++ 11 files changed, 23 insertions(+), 12 deletions(-)