Hi Hans,
On 17 June 2015 at 13:33, Hans de Goede hdegoede@redhat.com wrote:
On an usb stop instead of leaving orphan usb devices behind simply remove
On a usb_stop()
or
On a 'usb stop' command
?
them. This requires CONFIG_DM_DEVICE_REMOVE to be set, so only build usb_stop() when that is set.
This seems a little unfortunate. I can see the reasoning, but do you think this is necessary? I suspect people chasing code size may remove that option and still want to use USB properly.
The result of this commit is best seen in the output of "dm tree" after plugging out an usb hub with 2 devices plugges in and plugging in a keyb. instead, before this commit the output would be:
usb [ + ] `-- sunxi-musb usb_hub [ ] |-- usb_hub usb_mass_st [ ] | |-- usb_mass_storage usb_dev_gen [ ] | `-- generic_bus_0_dev_3 usb_dev_gen [ + ] `-- generic_bus_0_dev_1
Notice the non active usb_hub child and its 2 non active children. The first child being non-active as in this example also causes usb_get_dev_index to return NULL when probing the first child, which results in the usb kbd code not binding to the keyboard.
Although I suspect that could be fixed.
With this commit in place the output after swapping and "usb reset" is:
usb [ + ] `-- sunxi-musb usb_dev_gen [ + ] `-- generic_bus_0_dev_1
As expected, and usb_get_dev_index works properly and the keyboard works.
After this commit usb_find_child() is only necessary for emulated usb devices, so make its body #ifdef CONFIG_USB_EMUL.
Signed-off-by: Hans de Goede hdegoede@redhat.com
drivers/usb/host/usb-uclass.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c index bce6cec..8f26e35 100644 --- a/drivers/usb/host/usb-uclass.c +++ b/drivers/usb/host/usb-uclass.c @@ -128,6 +128,7 @@ int usb_alloc_device(struct usb_device *udev) return ops->alloc_device(bus, udev); }
+#ifdef CONFIG_DM_DEVICE_REMOVE int usb_stop(void) { struct udevice *bus; @@ -143,6 +144,12 @@ int usb_stop(void) uc_priv = uc->priv;
uclass_foreach_dev(bus, uc) {
ret = device_chld_remove(bus);if (ret && !err)err = ret;ret = device_chld_unbind(bus);if (ret && !err)err = ret; ret = device_remove(bus); if (ret && !err) err = ret;@@ -166,6 +173,7 @@ int usb_stop(void)
return err;} +#endif
static void usb_scan_bus(struct udevice *bus, bool recurse) { @@ -491,6 +499,7 @@ static int usb_find_child(struct udevice *parent, struct usb_interface_descriptor *iface, struct udevice **devp) { +#ifdef CONFIG_USB_EMUL /* Emulated devices are explictily bound */
explicitly
Can you add a comment about this? It seems that we should rename this function to usb_find_emul_child() and have it present only when CONFIG_USB_EMUL is around?
Also, why bother with the #ifdef if this function is never called outside sandbox?
struct udevice *dev; *devp = NULL;@@ -509,6 +518,7 @@ static int usb_find_child(struct udevice *parent, return 0; } } +#endif
return -ENOENT;}
2.4.3
Regards, Simon