| Message ID | YnqKAXKyp9Vq/pbn@rowland.harvard.edu (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | f9d76d15072caf1ec5558fa7cc6d93c7b9d33488 |
| Headers | show |
| Series | USB: gadget: Add ID numbers to gadget names | expand |
On Tue, May 10, 2022 at 11:51:29AM -0400, Alan Stern wrote: > Putting USB gadgets on a new bus of their own encounters a problem > when multiple gadgets are present: They all have the same name! The > driver core fails with a "sys: cannot create duplicate filename" error > when creating any of the /sys/bus/gadget/devices/<gadget-name> > symbolic links after the first. > > This patch fixes the problem by adding a ".N" suffix to each gadget's > name when the gadget is registered (where N is a unique ID number), > thus making the names distinct. > > Reported-and-tested-by: Geert Uytterhoeven <geert+renesas@glider.be> > Signed-off-by: Alan Stern <stern@rowland.harvard.edu> > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> > Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets") > > --- > > > [as1980] Thanks, let me run this through the Android test suite first. You can see the results here: https://android-review.googlesource.com/c/kernel/common/+/2095109 I'll let you know how it goes as I do not know if you are not logged in if you can see the test results or not, gerrit is odd... thanks, greg k-h
On Wed, May 11, 2022 at 05:17:48PM +0200, Greg KH wrote: > On Tue, May 10, 2022 at 11:51:29AM -0400, Alan Stern wrote: > > Putting USB gadgets on a new bus of their own encounters a problem > > when multiple gadgets are present: They all have the same name! The > > driver core fails with a "sys: cannot create duplicate filename" error > > when creating any of the /sys/bus/gadget/devices/<gadget-name> > > symbolic links after the first. > > > > This patch fixes the problem by adding a ".N" suffix to each gadget's > > name when the gadget is registered (where N is a unique ID number), > > thus making the names distinct. > > > > Reported-and-tested-by: Geert Uytterhoeven <geert+renesas@glider.be> > > Signed-off-by: Alan Stern <stern@rowland.harvard.edu> > > Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> > > Fixes: fc274c1e9973 ("USB: gadget: Add a new bus for gadgets") > > > > --- > > > > > > [as1980] > > Thanks, let me run this through the Android test suite first. You can > see the results here: > https://android-review.googlesource.com/c/kernel/common/+/2095109 > > I'll let you know how it goes as I do not know if you are not logged in > if you can see the test results or not, gerrit is odd... All passed, so I'll go queue this up now, thanks! greg k-h
Index: usb-devel/drivers/usb/gadget/udc/core.c =================================================================== --- usb-devel.orig/drivers/usb/gadget/udc/core.c +++ usb-devel/drivers/usb/gadget/udc/core.c @@ -12,6 +12,7 @@ #include <linux/module.h> #include <linux/device.h> #include <linux/list.h> +#include <linux/idr.h> #include <linux/err.h> #include <linux/dma-mapping.h> #include <linux/sched/task_stack.h> @@ -23,6 +24,8 @@ #include "trace.h" +static DEFINE_IDA(gadget_id_numbers); + static struct bus_type gadget_bus_type; /** @@ -1248,7 +1251,6 @@ static void usb_udc_nop_release(struct d void usb_initialize_gadget(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)) { - dev_set_name(&gadget->dev, "gadget"); INIT_WORK(&gadget->work, usb_gadget_state_work); gadget->dev.parent = parent; @@ -1304,12 +1306,21 @@ int usb_add_gadget(struct usb_gadget *ga usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); udc->vbus = true; + ret = ida_alloc(&gadget_id_numbers, GFP_KERNEL); + if (ret < 0) + goto err_del_udc; + gadget->id_number = ret; + dev_set_name(&gadget->dev, "gadget.%d", ret); + ret = device_add(&gadget->dev); if (ret) - goto err_del_udc; + goto err_free_id; return 0; + err_free_id: + ida_free(&gadget_id_numbers, gadget->id_number); + err_del_udc: flush_work(&gadget->work); device_del(&udc->dev); @@ -1417,6 +1428,7 @@ void usb_del_gadget(struct usb_gadget *g kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); flush_work(&gadget->work); device_del(&gadget->dev); + ida_free(&gadget_id_numbers, gadget->id_number); device_unregister(&udc->dev); } EXPORT_SYMBOL_GPL(usb_del_gadget); Index: usb-devel/include/linux/usb/gadget.h =================================================================== --- usb-devel.orig/include/linux/usb/gadget.h +++ usb-devel/include/linux/usb/gadget.h @@ -386,6 +386,7 @@ struct usb_gadget_ops { * @lpm_capable: If the gadget max_speed is FULL or HIGH, this flag * indicates that it supports LPM as per the LPM ECN & errata. * @irq: the interrupt number for device controller. + * @id_number: a unique ID number for ensuring that gadget names are distinct * * Gadgets have a mostly-portable "gadget driver" implementing device * functions, handling all usb configurations and interfaces. Gadget @@ -446,6 +447,7 @@ struct usb_gadget { unsigned connected:1; unsigned lpm_capable:1; int irq; + int id_number; }; #define work_to_gadget(w) (container_of((w), struct usb_gadget, work))