diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c index 325cbc9c35d8..b1298f093f13 100644 --- a/drivers/usb/core/config.c +++ b/drivers/usb/core/config.c @@ -949,6 +949,14 @@ int usb_get_bos_descriptor(struct usb_device *dev) dev->bos->ss_id = (struct usb_ss_container_id_descriptor *)buffer; break; + case USB_CAP_TYPE_CONFIG_SUMMARY: + /* one such desc per configuration */ + if (!dev->bos->num_config_summary_desc) + dev->bos->config_summary = + (struct usb_config_summary_descriptor *)buffer; + + dev->bos->num_config_summary_desc++; + break; default: break; } diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c index 358ca8dd784f..72d1109f13eb 100644 --- a/drivers/usb/core/generic.c +++ b/drivers/usb/core/generic.c @@ -19,6 +19,8 @@ #include #include +#include +#include #include "usb.h" static inline const char *plural(int n) @@ -40,6 +42,36 @@ static int is_activesync(struct usb_interface_descriptor *desc) && desc->bInterfaceProtocol == 1; } +static int usb_audio_max_rev_config(struct usb_host_bos *bos) +{ + int desc_cnt, func_cnt, numfunc; + int num_cfg_desc; + struct usb_config_summary_descriptor *conf_summary; + + if (!bos || !bos->config_summary) + goto done; + + conf_summary = bos->config_summary; + num_cfg_desc = bos->num_config_summary_desc; + + for (desc_cnt = 0; desc_cnt < num_cfg_desc; desc_cnt++) { + numfunc = conf_summary->bNumFunctions; + for (func_cnt = 0; func_cnt < numfunc; func_cnt++) { + /* look for BADD 3.0 */ + if (conf_summary->cs_info[func_cnt].bClass == + USB_CLASS_AUDIO && + conf_summary->cs_info[func_cnt].bProtocol == + UAC_VERSION_3 && + conf_summary->cs_info[func_cnt].bSubClass != + FULL_ADC_PROFILE) + return conf_summary->bConfigurationValue; + } + } + +done: + return -EINVAL; +} + int usb_choose_configuration(struct usb_device *udev) { int i; @@ -130,7 +162,6 @@ int usb_choose_configuration(struct usb_device *udev) best = c; break; } - /* If all the remaining configs are vendor-specific, * choose the first one. */ else if (!best) @@ -143,7 +174,10 @@ int usb_choose_configuration(struct usb_device *udev) insufficient_power, plural(insufficient_power)); if (best) { - i = best->desc.bConfigurationValue; + /* choose usb audio class preferred config if available */ + i = usb_audio_max_rev_config(udev->bos); + if (i < 0) + i = best->desc.bConfigurationValue; dev_dbg(&udev->dev, "configuration #%d chosen from %d choice%s\n", i, num_configs, plural(num_configs)); diff --git a/include/linux/usb.h b/include/linux/usb.h index a55f127d6836..e8b2ed4ad851 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -330,6 +330,8 @@ struct usb_host_bos { struct usb_ss_cap_descriptor *ss_cap; struct usb_ssp_cap_descriptor *ssp_cap; struct usb_ss_container_id_descriptor *ss_id; + struct usb_config_summary_descriptor *config_summary; + unsigned int num_config_summary_desc; }; int __usb_get_extra_descriptor(char *buffer, unsigned size, diff --git a/include/uapi/linux/usb/ch9.h b/include/uapi/linux/usb/ch9.h index 779a62aafafe..d3ab3f57aa9f 100644 --- a/include/uapi/linux/usb/ch9.h +++ b/include/uapi/linux/usb/ch9.h @@ -894,6 +894,29 @@ struct usb_ssp_cap_descriptor { #define USB_SSP_SUBLINK_SPEED_LSM (0xff << 16) /* Lanespeed mantissa */ } __attribute__((packed)); +/* + * Configuration Summary descriptors: Defines a list of functions in the + * configuration. This descriptor may be used by Host software to decide + * which Configuration to use to obtain the desired functionality. + */ +#define USB_CAP_TYPE_CONFIG_SUMMARY 0x10 + +struct function_class_info { + __u8 bClass; + __u8 bSubClass; + __u8 bProtocol; +}; + +struct usb_config_summary_descriptor { + __u8 bLength; + __u8 bDescriptorType; + __u8 bDevCapabilityType; + __u16 bcdVersion; + __u8 bConfigurationValue; + __u8 bMaxPower; + __u8 bNumFunctions; + struct function_class_info cs_info[]; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/