On 21-11-01 09:57:57, Qihang Hu wrote:
> In the config_ep_by_speed_and_alt function, select the corresponding
> descriptor through g->speed, but the interface driver
function driver
> may not
> support the corresponding speed. So, we need to check whether the
> interface driver provides the corresponding speed descriptor when
> selecting the descriptor.
>
> [ 237.708146] android_work: sent uevent USB_STATE=CONNECTED
> [ 237.712464] kconfigfs-gadget gadget: super-speed config #1: b
> [ 237.712487] kUnable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> [ 237.712493] kMem abort info:
> [ 237.712498] k ESR = 0x96000006
> [ 237.712504] k EC = 0x25: DABT (current EL), IL = 32 bits
> [ 237.712510] k SET = 0, FnV = 0
> [ 237.712515] k EA = 0, S1PTW = 0
> [ 237.712520] kData abort info:
> [ 237.712525] k ISV = 0, ISS = 0x00000006
> [ 237.712530] k CM = 0, WnR = 0
> [ 237.712536] kuser pgtable: 4k pages, 39-bit VAs, pgdp=000000020ef29000
> [ 237.712541] k[0000000000000000] pgd=000000020ef2a003, pud=000000020ef2a003, pmd=0000000000000000
> [ 237.712554] kInternal error: Oops: 96000006 [#1] PREEMPT SMP
> [ 237.722067] kSkip md ftrace buffer dump for: 0x1609e0
> [ 237.787037] kWorkqueue: dwc_wq dwc3_bh_work.cfi_jt
> [ 237.854922] kpstate: 60c00085 (nZCv daIf +PAN +UAO)
> [ 237.863165] kpc : config_ep_by_speed_and_alt+0x90/0x308
> [ 237.871766] klr : audio_set_alt+0x54/0x78
> [ 237.879108] ksp : ffffffc0104839e0
>
> Signed-off-by: Qihang Hu <huqihang@xxxxxxxx>
> ---
> drivers/usb/gadget/composite.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
> index 72a9797dbbae..443a65af98af 100644
> --- a/drivers/usb/gadget/composite.c
> +++ b/drivers/usb/gadget/composite.c
> @@ -166,21 +166,21 @@ int config_ep_by_speed_and_alt(struct usb_gadget *g,
> /* select desired speed */
> switch (g->speed) {
> case USB_SPEED_SUPER_PLUS:
> - if (gadget_is_superspeed_plus(g)) {
> + if (gadget_is_superspeed_plus(g) && f->ssp_descriptors) {
> speed_desc = f->ssp_descriptors;
> want_comp_desc = 1;
> break;
> }
> fallthrough;
> case USB_SPEED_SUPER:
> - if (gadget_is_superspeed(g)) {
> + if (gadget_is_superspeed(g) && f->ss_descriptors) {
> speed_desc = f->ss_descriptors;
> want_comp_desc = 1;
> break;
> }
> fallthrough;
> case USB_SPEED_HIGH:
> - if (gadget_is_dualspeed(g)) {
> + if (gadget_is_dualspeed(g) && f->hs_descriptors) {
> speed_desc = f->hs_descriptors;
> break;
> }
> --
> 2.25.1
>
Besides your fix, you may show an warning that said "the function
doesn't hold the descriptors for supported speed, using the default (FS)
descriptors". See below kernel doc for detail.
/**
* config_ep_by_speed_and_alt() - configures the given endpoint
*
* ....
* Note: the supplied function should hold all the descriptors
* for supported speeds
*/
What's more, you may fix android f_audio_source.c, and let it support
super speed and super speed plus.
--
Thanks,
Peter Chen
