From: Pawel Laszczak pawell@cadence.com
[ Upstream commit 5d363120aa548ba52d58907a295eee25f8207ed2 ]
This patch adds new config_ep_by_speed_and_alt function which extends the config_ep_by_speed about alt parameter. This additional parameter allows to find proper usb_ss_ep_comp_descriptor.
Problem has appeared during testing f_tcm (BOT/UAS) driver function.
f_tcm function for SS use array of headers for both BOT/UAS alternate setting:
static struct usb_descriptor_header *uasp_ss_function_desc[] = { (struct usb_descriptor_header *) &bot_intf_desc, (struct usb_descriptor_header *) &uasp_ss_bi_desc, (struct usb_descriptor_header *) &bot_bi_ep_comp_desc, (struct usb_descriptor_header *) &uasp_ss_bo_desc, (struct usb_descriptor_header *) &bot_bo_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_intf_desc, (struct usb_descriptor_header *) &uasp_ss_bi_desc, (struct usb_descriptor_header *) &uasp_bi_ep_comp_desc, (struct usb_descriptor_header *) &uasp_bi_pipe_desc, (struct usb_descriptor_header *) &uasp_ss_bo_desc, (struct usb_descriptor_header *) &uasp_bo_ep_comp_desc, (struct usb_descriptor_header *) &uasp_bo_pipe_desc, (struct usb_descriptor_header *) &uasp_ss_status_desc, (struct usb_descriptor_header *) &uasp_status_in_ep_comp_desc, (struct usb_descriptor_header *) &uasp_status_pipe_desc, (struct usb_descriptor_header *) &uasp_ss_cmd_desc, (struct usb_descriptor_header *) &uasp_cmd_comp_desc, (struct usb_descriptor_header *) &uasp_cmd_pipe_desc, NULL, };
The first 5 descriptors are associated with BOT alternate setting, and others are associated with UAS.
During handling UAS alternate setting f_tcm driver invokes config_ep_by_speed and this function sets incorrect companion endpoint descriptor in usb_ep object.
Instead setting ep->comp_desc to uasp_bi_ep_comp_desc function in this case set ep->comp_desc to uasp_ss_bi_desc.
This is due to the fact that it searches endpoint based on endpoint address:
for_each_ep_desc(speed_desc, d_spd) { chosen_desc = (struct usb_endpoint_descriptor *)*d_spd; if (chosen_desc->bEndpoitAddress == _ep->address) goto ep_found; }
And in result it uses the descriptor from BOT alternate setting instead UAS.
Finally, it causes that controller driver during enabling endpoints detect that just enabled endpoint for bot.
Signed-off-by: Jayshri Pawar jpawar@cadence.com Signed-off-by: Pawel Laszczak pawell@cadence.com Signed-off-by: Felipe Balbi balbi@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/usb/gadget/composite.c | 78 ++++++++++++++++++++++++++-------- include/linux/usb/composite.h | 3 ++ 2 files changed, 64 insertions(+), 17 deletions(-)
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index cb4950cf1cdc..5c1eb96a5c57 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -96,40 +96,43 @@ function_descriptors(struct usb_function *f, }
/** - * next_ep_desc() - advance to the next EP descriptor + * next_desc() - advance to the next desc_type descriptor * @t: currect pointer within descriptor array + * @desc_type: descriptor type * - * Return: next EP descriptor or NULL + * Return: next desc_type descriptor or NULL * - * Iterate over @t until either EP descriptor found or + * Iterate over @t until either desc_type descriptor found or * NULL (that indicates end of list) encountered */ static struct usb_descriptor_header** -next_ep_desc(struct usb_descriptor_header **t) +next_desc(struct usb_descriptor_header **t, u8 desc_type) { for (; *t; t++) { - if ((*t)->bDescriptorType == USB_DT_ENDPOINT) + if ((*t)->bDescriptorType == desc_type) return t; } return NULL; }
/* - * for_each_ep_desc()- iterate over endpoint descriptors in the - * descriptors list - * @start: pointer within descriptor array. - * @ep_desc: endpoint descriptor to use as the loop cursor + * for_each_desc() - iterate over desc_type descriptors in the + * descriptors list + * @start: pointer within descriptor array. + * @iter_desc: desc_type descriptor to use as the loop cursor + * @desc_type: wanted descriptr type */ -#define for_each_ep_desc(start, ep_desc) \ - for (ep_desc = next_ep_desc(start); \ - ep_desc; ep_desc = next_ep_desc(ep_desc+1)) +#define for_each_desc(start, iter_desc, desc_type) \ + for (iter_desc = next_desc(start, desc_type); \ + iter_desc; iter_desc = next_desc(iter_desc + 1, desc_type))
/** - * config_ep_by_speed() - configures the given endpoint + * config_ep_by_speed_and_alt() - configures the given endpoint * according to gadget speed. * @g: pointer to the gadget * @f: usb function * @_ep: the endpoint to configure + * @alt: alternate setting number * * Return: error code, 0 on success * @@ -142,11 +145,13 @@ next_ep_desc(struct usb_descriptor_header **t) * Note: the supplied function should hold all the descriptors * for supported speeds */ -int config_ep_by_speed(struct usb_gadget *g, - struct usb_function *f, - struct usb_ep *_ep) +int config_ep_by_speed_and_alt(struct usb_gadget *g, + struct usb_function *f, + struct usb_ep *_ep, + u8 alt) { struct usb_endpoint_descriptor *chosen_desc = NULL; + struct usb_interface_descriptor *int_desc = NULL; struct usb_descriptor_header **speed_desc = NULL;
struct usb_ss_ep_comp_descriptor *comp_desc = NULL; @@ -182,8 +187,21 @@ int config_ep_by_speed(struct usb_gadget *g, default: speed_desc = f->fs_descriptors; } + + /* find correct alternate setting descriptor */ + for_each_desc(speed_desc, d_spd, USB_DT_INTERFACE) { + int_desc = (struct usb_interface_descriptor *)*d_spd; + + if (int_desc->bAlternateSetting == alt) { + speed_desc = d_spd; + goto intf_found; + } + } + return -EIO; + +intf_found: /* find descriptors */ - for_each_ep_desc(speed_desc, d_spd) { + for_each_desc(speed_desc, d_spd, USB_DT_ENDPOINT) { chosen_desc = (struct usb_endpoint_descriptor *)*d_spd; if (chosen_desc->bEndpointAddress == _ep->address) goto ep_found; @@ -237,6 +255,32 @@ int config_ep_by_speed(struct usb_gadget *g, } return 0; } +EXPORT_SYMBOL_GPL(config_ep_by_speed_and_alt); + +/** + * config_ep_by_speed() - configures the given endpoint + * according to gadget speed. + * @g: pointer to the gadget + * @f: usb function + * @_ep: the endpoint to configure + * + * Return: error code, 0 on success + * + * This function chooses the right descriptors for a given + * endpoint according to gadget speed and saves it in the + * endpoint desc field. If the endpoint already has a descriptor + * assigned to it - overwrites it with currently corresponding + * descriptor. The endpoint maxpacket field is updated according + * to the chosen descriptor. + * Note: the supplied function should hold all the descriptors + * for supported speeds + */ +int config_ep_by_speed(struct usb_gadget *g, + struct usb_function *f, + struct usb_ep *_ep) +{ + return config_ep_by_speed_and_alt(g, f, _ep, 0); +} EXPORT_SYMBOL_GPL(config_ep_by_speed);
/** diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h index 8675e145ea8b..2040696d75b6 100644 --- a/include/linux/usb/composite.h +++ b/include/linux/usb/composite.h @@ -249,6 +249,9 @@ int usb_function_activate(struct usb_function *);
int usb_interface_id(struct usb_configuration *, struct usb_function *);
+int config_ep_by_speed_and_alt(struct usb_gadget *g, struct usb_function *f, + struct usb_ep *_ep, u8 alt); + int config_ep_by_speed(struct usb_gadget *g, struct usb_function *f, struct usb_ep *_ep);