From dfb05b5dc3afd90e564b69b88ff6be6947a0f32f Mon Sep 17 00:00:00 2001 From: Yunhao Tian Date: Sat, 22 Jan 2022 19:24:40 +0800 Subject: [PATCH] usb: gadget: f_uac1: allow changing interface name via configfs This adds "function_name" configfs entry to change string value of the iInterface field. This field will be shown in Windows' audio settings panel, so being able to change it is useful. It will default to "AC Interface" just as before if unchanged. Signed-off-by: Yunhao Tian Link: https://lore.kernel.org/r/20220122112446.1415547-1-t123yh.xyz@gmail.com Signed-off-by: Greg Kroah-Hartman --- Documentation/ABI/testing/configfs-usb-gadget-uac1 | 1 + Documentation/usb/gadget-testing.rst | 1 + drivers/usb/gadget/function/f_uac1.c | 46 +++++++++++++++++++++- drivers/usb/gadget/function/u_uac1.h | 2 + 4 files changed, 49 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac1 b/Documentation/ABI/testing/configfs-usb-gadget-uac1 index 09725e2..c4ba92f 100644 --- a/Documentation/ABI/testing/configfs-usb-gadget-uac1 +++ b/Documentation/ABI/testing/configfs-usb-gadget-uac1 @@ -29,4 +29,5 @@ Description: (in 1/256 dB) req_number the number of pre-allocated requests for both capture and playback + function_name name of the interface ===================== ======================================= diff --git a/Documentation/usb/gadget-testing.rst b/Documentation/usb/gadget-testing.rst index 046842b..1792bd8 100644 --- a/Documentation/usb/gadget-testing.rst +++ b/Documentation/usb/gadget-testing.rst @@ -745,6 +745,7 @@ The uac2 function provides these attributes in its function directory: p_volume_res playback volume control resolution (in 1/256 dB) req_number the number of pre-allocated request for both capture and playback + function_name name of the interface ================ ==================================================== The attributes have sane default values. diff --git a/drivers/usb/gadget/function/f_uac1.c b/drivers/usb/gadget/function/f_uac1.c index 1484e5c..6f0e1d8 100644 --- a/drivers/usb/gadget/function/f_uac1.c +++ b/drivers/usb/gadget/function/f_uac1.c @@ -309,7 +309,7 @@ enum { }; static struct usb_string strings_uac1[] = { - [STR_AC_IF].s = "AC Interface", + /* [STR_AC_IF].s = DYNAMIC, */ [STR_USB_OUT_IT].s = "Playback Input terminal", [STR_USB_OUT_IT_CH_NAMES].s = "Playback Channels", [STR_IO_OUT_OT].s = "Playback Output terminal", @@ -1192,6 +1192,8 @@ static int f_audio_bind(struct usb_configuration *c, struct usb_function *f) audio_opts = container_of(f->fi, struct f_uac1_opts, func_inst); + strings_uac1[STR_AC_IF].s = audio_opts->function_name; + us = usb_gstrings_attach(cdev, uac1_strings, ARRAY_SIZE(strings_uac1)); if (IS_ERR(us)) return PTR_ERR(us); @@ -1551,6 +1553,42 @@ end: \ \ CONFIGFS_ATTR(f_uac1_opts_, name) +#define UAC1_ATTRIBUTE_STRING(name) \ +static ssize_t f_uac1_opts_##name##_show(struct config_item *item, \ + char *page) \ +{ \ + struct f_uac1_opts *opts = to_f_uac1_opts(item); \ + int result; \ + \ + mutex_lock(&opts->lock); \ + result = snprintf(page, sizeof(opts->name), "%s", opts->name); \ + mutex_unlock(&opts->lock); \ + \ + return result; \ +} \ + \ +static ssize_t f_uac1_opts_##name##_store(struct config_item *item, \ + const char *page, size_t len) \ +{ \ + struct f_uac1_opts *opts = to_f_uac1_opts(item); \ + int ret = 0; \ + \ + mutex_lock(&opts->lock); \ + if (opts->refcnt) { \ + ret = -EBUSY; \ + goto end; \ + } \ + \ + ret = snprintf(opts->name, min(sizeof(opts->name), len), \ + "%s", page); \ + \ +end: \ + mutex_unlock(&opts->lock); \ + return ret; \ +} \ + \ +CONFIGFS_ATTR(f_uac1_opts_, name) + UAC1_ATTRIBUTE(u32, c_chmask); UAC1_RATE_ATTRIBUTE(c_srate); UAC1_ATTRIBUTE(u32, c_ssize); @@ -1570,6 +1608,7 @@ UAC1_ATTRIBUTE(bool, c_volume_present); UAC1_ATTRIBUTE(s16, c_volume_min); UAC1_ATTRIBUTE(s16, c_volume_max); UAC1_ATTRIBUTE(s16, c_volume_res); +UAC1_ATTRIBUTE_STRING(function_name); static struct configfs_attribute *f_uac1_attrs[] = { &f_uac1_opts_attr_c_chmask, @@ -1592,6 +1631,8 @@ static struct configfs_attribute *f_uac1_attrs[] = { &f_uac1_opts_attr_c_volume_max, &f_uac1_opts_attr_c_volume_res, + &f_uac1_opts_attr_function_name, + NULL, }; @@ -1643,6 +1684,9 @@ static struct usb_function_instance *f_audio_alloc_inst(void) opts->c_volume_res = UAC1_DEF_RES_DB; opts->req_number = UAC1_DEF_REQ_NUM; + + snprintf(opts->function_name, sizeof(opts->function_name), "AC Interface"); + return &opts->func_inst; } diff --git a/drivers/usb/gadget/function/u_uac1.h b/drivers/usb/gadget/function/u_uac1.h index b6cd617..f7a6167 100644 --- a/drivers/usb/gadget/function/u_uac1.h +++ b/drivers/usb/gadget/function/u_uac1.h @@ -52,6 +52,8 @@ struct f_uac1_opts { int req_number; unsigned bound:1; + char function_name[32]; + struct mutex lock; int refcnt; }; -- 2.7.4