Re: [PATCH v4 2/3] usb: gadget: f_uac2: split out audio core
From: Jassi Brar
Date: Fri Jun 02 2017 - 07:47:45 EST
On Tue, May 30, 2017 at 5:13 AM, Ruslan Bilovol
<ruslan.bilovol@xxxxxxxxx> wrote:
> On Mon, May 22, 2017 at 6:58 PM, Jassi Brar <jassisinghbrar@xxxxxxxxx> wrote:
>> On Thu, May 18, 2017 at 4:07 AM, Ruslan Bilovol
>> <ruslan.bilovol@xxxxxxxxx> wrote:
>>> Abstract the peripheral side ALSA sound card code from
>>> the f_uac2 function into a component that can be called
>>> by various functions, so the various flavors can be split
>>> apart and selectively reused.
>>>
>>> Visible changes:
>>> - add uac_params structure to pass audio paramteres for
>>> g_audio_setup
>>> - make ALSA sound card's name configurable
>>> - add [in/out]_ep_maxpsize
>>> - allocate snd_uac_chip structure during g_audio_setup
>>> - add u_audio_[start/stop]_[capture/playback] functions
>>>
>>> Signed-off-by: Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx>
>>> ---
>>> drivers/usb/gadget/Kconfig | 4 +
>>> drivers/usb/gadget/function/Makefile | 1 +
>>> drivers/usb/gadget/function/f_uac2.c | 721 ++++------------------------------
>>> drivers/usb/gadget/function/u_audio.c | 661 +++++++++++++++++++++++++++++++
>>> drivers/usb/gadget/function/u_audio.h | 95 +++++
>>> drivers/usb/gadget/legacy/Kconfig | 1 +
>>> 6 files changed, 846 insertions(+), 637 deletions(-)
>>> create mode 100644 drivers/usb/gadget/function/u_audio.c
>>> create mode 100644 drivers/usb/gadget/function/u_audio.h
>>>
>>> diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
>>> index c164d6b..2ba0ace 100644
>>> --- a/drivers/usb/gadget/Kconfig
>>> +++ b/drivers/usb/gadget/Kconfig
>>> @@ -158,6 +158,9 @@ config USB_U_SERIAL
>>> config USB_U_ETHER
>>> tristate
>>>
>>> +config USB_U_AUDIO
>>> + tristate
>>> +
>>> config USB_F_SERIAL
>>> tristate
>>>
>>> @@ -381,6 +384,7 @@ config USB_CONFIGFS_F_UAC2
>>> depends on SND
>>> select USB_LIBCOMPOSITE
>>> select SND_PCM
>>> + select USB_U_AUDIO
>>> select USB_F_UAC2
>>> help
>>> This Audio function is compatible with USB Audio Class
>>> diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
>>> index cb8c225..b29f2ae 100644
>>> --- a/drivers/usb/gadget/function/Makefile
>>> +++ b/drivers/usb/gadget/function/Makefile
>>> @@ -32,6 +32,7 @@ usb_f_mass_storage-y := f_mass_storage.o storage_common.o
>>> obj-$(CONFIG_USB_F_MASS_STORAGE)+= usb_f_mass_storage.o
>>> usb_f_fs-y := f_fs.o
>>> obj-$(CONFIG_USB_F_FS) += usb_f_fs.o
>>> +obj-$(CONFIG_USB_U_AUDIO) += u_audio.o
>>> usb_f_uac1-y := f_uac1.o u_uac1.o
>>> obj-$(CONFIG_USB_F_UAC1) += usb_f_uac1.o
>>> usb_f_uac2-y := f_uac2.o
>>> diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
>>> index d4565b5..059a14a 100644
>>> --- a/drivers/usb/gadget/function/f_uac2.c
>>> +++ b/drivers/usb/gadget/function/f_uac2.c
>>> @@ -15,10 +15,7 @@
>>> #include <linux/usb/audio-v2.h>
>>> #include <linux/module.h>
>>>
>>> -#include <sound/core.h>
>>> -#include <sound/pcm.h>
>>> -#include <sound/pcm_params.h>
>>> -
>>> +#include "u_audio.h"
>>> #include "u_uac2.h"
>>>
>>> /*
>>> @@ -50,455 +47,23 @@
>>> #define UNFLW_CTRL 8
>>> #define OVFLW_CTRL 10
>>>
>>> -struct uac2_req {
>>> - struct uac2_rtd_params *pp; /* parent param */
>>> - struct usb_request *req;
>>> -};
>>> -
>>> -struct uac2_rtd_params {
>>> - struct snd_uac2_chip *uac2; /* parent chip */
>>> - bool ep_enabled; /* if the ep is enabled */
>>> - /* Size of the ring buffer */
>>> - size_t dma_bytes;
>>> - unsigned char *dma_area;
>>> -
>>> - struct snd_pcm_substream *ss;
>>> -
>>> - /* Ring buffer */
>>> - ssize_t hw_ptr;
>>> -
>>> - void *rbuf;
>>> -
>>> - size_t period_size;
>>> -
>>> - unsigned max_psize;
>>> - struct uac2_req *ureq;
>>> -
>>> - spinlock_t lock;
>>> -};
>>> -
>>> -struct snd_uac2_chip {
>>> - struct uac2_rtd_params p_prm;
>>> - struct uac2_rtd_params c_prm;
>>> -
>>> - struct snd_card *card;
>>> - struct snd_pcm *pcm;
>>> -
>>> - /* timekeeping for the playback endpoint */
>>> - unsigned int p_interval;
>>> - unsigned int p_residue;
>>> -
>>> - /* pre-calculated values for playback iso completion */
>>> - unsigned int p_pktsize;
>>> - unsigned int p_pktsize_residue;
>>> - unsigned int p_framesize;
>>> +struct f_uac2 {
>>> + struct g_audio g_audio;
>>> + u8 ac_intf, as_in_intf, as_out_intf;
>>> + u8 ac_alt, as_in_alt, as_out_alt; /* needed for get_alt() */
>>> };
>>>
>>> -#define BUFF_SIZE_MAX (PAGE_SIZE * 16)
>>> -#define PRD_SIZE_MAX PAGE_SIZE
>>> -#define MIN_PERIODS 4
>>> -
>>> -static struct snd_pcm_hardware uac2_pcm_hardware = {
>>> - .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER
>>> - | SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID
>>> - | SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
>>> - .rates = SNDRV_PCM_RATE_CONTINUOUS,
>>> - .periods_max = BUFF_SIZE_MAX / PRD_SIZE_MAX,
>>> - .buffer_bytes_max = BUFF_SIZE_MAX,
>>> - .period_bytes_max = PRD_SIZE_MAX,
>>> - .periods_min = MIN_PERIODS,
>>> -};
>>> -
>>> -struct audio_dev {
>>> - u8 ac_intf, ac_alt;
>>> - u8 as_out_intf, as_out_alt;
>>> - u8 as_in_intf, as_in_alt;
>>> -
>>> - struct usb_ep *in_ep, *out_ep;
>>> - struct usb_function func;
>>> - struct usb_gadget *gadget;
>>> -
>>> - /* The ALSA Sound Card it represents on the USB-Client side */
>>> - struct snd_uac2_chip uac2;
>>> -};
>>> -
>>> -static inline
>>> -struct audio_dev *func_to_agdev(struct usb_function *f)
>>> +static inline struct f_uac2 *func_to_uac2(struct usb_function *f)
>>> {
>>> - return container_of(f, struct audio_dev, func);
>>> + return container_of(f, struct f_uac2, g_audio.func);
>>> }
>>>
>>> static inline
>>> -struct audio_dev *uac2_to_agdev(struct snd_uac2_chip *u)
>>> -{
>>> - return container_of(u, struct audio_dev, uac2);
>>> -}
>>> -
>>> -static inline
>>> -struct f_uac2_opts *agdev_to_uac2_opts(struct audio_dev *agdev)
>>> +struct f_uac2_opts *g_audio_to_uac2_opts(struct g_audio *agdev)
>>> {
>>> return container_of(agdev->func.fi, struct f_uac2_opts, func_inst);
>>> }
>>>
>>> -static inline
>>> -uint num_channels(uint chanmask)
>>> -{
>>> - uint num = 0;
>>> -
>>> - while (chanmask) {
>>> - num += (chanmask & 1);
>>> - chanmask >>= 1;
>>> - }
>>> -
>>> - return num;
>>> -}
>>> -
>>> -static void
>>> -agdev_iso_complete(struct usb_ep *ep, struct usb_request *req)
>>> -{
>>> - unsigned pending;
>>> - unsigned long flags;
>>> - unsigned int hw_ptr;
>>> - bool update_alsa = false;
>>> - int status = req->status;
>>> - struct uac2_req *ur = req->context;
>>> - struct snd_pcm_substream *substream;
>>> - struct uac2_rtd_params *prm = ur->pp;
>>> - struct snd_uac2_chip *uac2 = prm->uac2;
>>> -
>>> - /* i/f shutting down */
>>> - if (!prm->ep_enabled || req->status == -ESHUTDOWN)
>>> - return;
>>> -
>>> - /*
>>> - * We can't really do much about bad xfers.
>>> - * Afterall, the ISOCH xfers could fail legitimately.
>>> - */
>>> - if (status)
>>> - pr_debug("%s: iso_complete status(%d) %d/%d\n",
>>> - __func__, status, req->actual, req->length);
>>> -
>>> - substream = prm->ss;
>>> -
>>> - /* Do nothing if ALSA isn't active */
>>> - if (!substream)
>>> - goto exit;
>>> -
>>> - spin_lock_irqsave(&prm->lock, flags);
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
>>> - /*
>>> - * For each IN packet, take the quotient of the current data
>>> - * rate and the endpoint's interval as the base packet size.
>>> - * If there is a residue from this division, add it to the
>>> - * residue accumulator.
>>> - */
>>> - req->length = uac2->p_pktsize;
>>> - uac2->p_residue += uac2->p_pktsize_residue;
>>> -
>>> - /*
>>> - * Whenever there are more bytes in the accumulator than we
>>> - * need to add one more sample frame, increase this packet's
>>> - * size and decrease the accumulator.
>>> - */
>>> - if (uac2->p_residue / uac2->p_interval >= uac2->p_framesize) {
>>> - req->length += uac2->p_framesize;
>>> - uac2->p_residue -= uac2->p_framesize *
>>> - uac2->p_interval;
>>> - }
>>> -
>>> - req->actual = req->length;
>>> - }
>>> -
>>> - pending = prm->hw_ptr % prm->period_size;
>>> - pending += req->actual;
>>> - if (pending >= prm->period_size)
>>> - update_alsa = true;
>>> -
>>> - hw_ptr = prm->hw_ptr;
>>> - prm->hw_ptr = (prm->hw_ptr + req->actual) % prm->dma_bytes;
>>> -
>>> - spin_unlock_irqrestore(&prm->lock, flags);
>>> -
>>> - /* Pack USB load in ALSA ring buffer */
>>> - pending = prm->dma_bytes - hw_ptr;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
>>> - if (unlikely(pending < req->actual)) {
>>> - memcpy(req->buf, prm->dma_area + hw_ptr, pending);
>>> - memcpy(req->buf + pending, prm->dma_area,
>>> - req->actual - pending);
>>> - } else {
>>> - memcpy(req->buf, prm->dma_area + hw_ptr, req->actual);
>>> - }
>>> - } else {
>>> - if (unlikely(pending < req->actual)) {
>>> - memcpy(prm->dma_area + hw_ptr, req->buf, pending);
>>> - memcpy(prm->dma_area, req->buf + pending,
>>> - req->actual - pending);
>>> - } else {
>>> - memcpy(prm->dma_area + hw_ptr, req->buf, req->actual);
>>> - }
>>> - }
>>> -
>>> -exit:
>>> - if (usb_ep_queue(ep, req, GFP_ATOMIC))
>>> - dev_err(uac2->card->dev, "%d Error!\n", __LINE__);
>>> -
>>> - if (update_alsa)
>>> - snd_pcm_period_elapsed(substream);
>>> -
>>> - return;
>>> -}
>>> -
>>> -static int
>>> -uac2_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
>>> -{
>>> - struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
>>> - struct audio_dev *agdev = uac2_to_agdev(uac2);
>>> - struct f_uac2_opts *uac2_opts = agdev_to_uac2_opts(agdev);
>>> - struct uac2_rtd_params *prm;
>>> - unsigned long flags;
>>> - int err = 0;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>>> - prm = &uac2->p_prm;
>>> - else
>>> - prm = &uac2->c_prm;
>>> -
>>> - spin_lock_irqsave(&prm->lock, flags);
>>> -
>>> - /* Reset */
>>> - prm->hw_ptr = 0;
>>> -
>>> - switch (cmd) {
>>> - case SNDRV_PCM_TRIGGER_START:
>>> - case SNDRV_PCM_TRIGGER_RESUME:
>>> - prm->ss = substream;
>>> - break;
>>> - case SNDRV_PCM_TRIGGER_STOP:
>>> - case SNDRV_PCM_TRIGGER_SUSPEND:
>>> - prm->ss = NULL;
>>> - break;
>>> - default:
>>> - err = -EINVAL;
>>> - }
>>> -
>>> - spin_unlock_irqrestore(&prm->lock, flags);
>>> -
>>> - /* Clear buffer after Play stops */
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && !prm->ss)
>>> - memset(prm->rbuf, 0, prm->max_psize * uac2_opts->req_number);
>>> -
>>> - return err;
>>> -}
>>> -
>>> -static snd_pcm_uframes_t uac2_pcm_pointer(struct snd_pcm_substream *substream)
>>> -{
>>> - struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
>>> - struct uac2_rtd_params *prm;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>>> - prm = &uac2->p_prm;
>>> - else
>>> - prm = &uac2->c_prm;
>>> -
>>> - return bytes_to_frames(substream->runtime, prm->hw_ptr);
>>> -}
>>> -
>>> -static int uac2_pcm_hw_params(struct snd_pcm_substream *substream,
>>> - struct snd_pcm_hw_params *hw_params)
>>> -{
>>> - struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
>>> - struct uac2_rtd_params *prm;
>>> - int err;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>>> - prm = &uac2->p_prm;
>>> - else
>>> - prm = &uac2->c_prm;
>>> -
>>> - err = snd_pcm_lib_malloc_pages(substream,
>>> - params_buffer_bytes(hw_params));
>>> - if (err >= 0) {
>>> - prm->dma_bytes = substream->runtime->dma_bytes;
>>> - prm->dma_area = substream->runtime->dma_area;
>>> - prm->period_size = params_period_bytes(hw_params);
>>> - }
>>> -
>>> - return err;
>>> -}
>>> -
>>> -static int uac2_pcm_hw_free(struct snd_pcm_substream *substream)
>>> -{
>>> - struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
>>> - struct uac2_rtd_params *prm;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
>>> - prm = &uac2->p_prm;
>>> - else
>>> - prm = &uac2->c_prm;
>>> -
>>> - prm->dma_area = NULL;
>>> - prm->dma_bytes = 0;
>>> - prm->period_size = 0;
>>> -
>>> - return snd_pcm_lib_free_pages(substream);
>>> -}
>>> -
>>> -static int uac2_pcm_open(struct snd_pcm_substream *substream)
>>> -{
>>> - struct snd_uac2_chip *uac2 = snd_pcm_substream_chip(substream);
>>> - struct snd_pcm_runtime *runtime = substream->runtime;
>>> - struct audio_dev *audio_dev;
>>> - struct f_uac2_opts *opts;
>>> - int p_ssize, c_ssize;
>>> - int p_srate, c_srate;
>>> - int p_chmask, c_chmask;
>>> -
>>> - audio_dev = uac2_to_agdev(uac2);
>>> - opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
>>> - p_ssize = opts->p_ssize;
>>> - c_ssize = opts->c_ssize;
>>> - p_srate = opts->p_srate;
>>> - c_srate = opts->c_srate;
>>> - p_chmask = opts->p_chmask;
>>> - c_chmask = opts->c_chmask;
>>> - uac2->p_residue = 0;
>>> -
>>> - runtime->hw = uac2_pcm_hardware;
>>> -
>>> - if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
>>> - spin_lock_init(&uac2->p_prm.lock);
>>> - runtime->hw.rate_min = p_srate;
>>> - switch (p_ssize) {
>>> - case 3:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
>>> - break;
>>> - case 4:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
>>> - break;
>>> - default:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
>>> - break;
>>> - }
>>> - runtime->hw.channels_min = num_channels(p_chmask);
>>> - runtime->hw.period_bytes_min = 2 * uac2->p_prm.max_psize
>>> - / runtime->hw.periods_min;
>>> - } else {
>>> - spin_lock_init(&uac2->c_prm.lock);
>>> - runtime->hw.rate_min = c_srate;
>>> - switch (c_ssize) {
>>> - case 3:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S24_3LE;
>>> - break;
>>> - case 4:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S32_LE;
>>> - break;
>>> - default:
>>> - runtime->hw.formats = SNDRV_PCM_FMTBIT_S16_LE;
>>> - break;
>>> - }
>>> - runtime->hw.channels_min = num_channels(c_chmask);
>>> - runtime->hw.period_bytes_min = 2 * uac2->c_prm.max_psize
>>> - / runtime->hw.periods_min;
>>> - }
>>> -
>>> - runtime->hw.rate_max = runtime->hw.rate_min;
>>> - runtime->hw.channels_max = runtime->hw.channels_min;
>>> -
>>> - snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
>>> -
>>> - return 0;
>>> -}
>>> -
>>> -/* ALSA cries without these function pointers */
>>> -static int uac2_pcm_null(struct snd_pcm_substream *substream)
>>> -{
>>> - return 0;
>>> -}
>>> -
>>> -static struct snd_pcm_ops uac2_pcm_ops = {
>>> - .open = uac2_pcm_open,
>>> - .close = uac2_pcm_null,
>>> - .ioctl = snd_pcm_lib_ioctl,
>>> - .hw_params = uac2_pcm_hw_params,
>>> - .hw_free = uac2_pcm_hw_free,
>>> - .trigger = uac2_pcm_trigger,
>>> - .pointer = uac2_pcm_pointer,
>>> - .prepare = uac2_pcm_null,
>>> -};
>>> -
>>> -static int snd_uac2_probe(struct audio_dev *audio_dev)
>>> -{
>>> - struct snd_uac2_chip *uac2 = &audio_dev->uac2;
>>> - struct snd_card *card;
>>> - struct snd_pcm *pcm;
>>> - struct f_uac2_opts *opts;
>>> - int err;
>>> - int p_chmask, c_chmask;
>>> -
>>> - opts = container_of(audio_dev->func.fi, struct f_uac2_opts, func_inst);
>>> - p_chmask = opts->p_chmask;
>>> - c_chmask = opts->c_chmask;
>>> -
>>> - /* Choose any slot, with no id */
>>> - err = snd_card_new(&audio_dev->gadget->dev,
>>> - -1, NULL, THIS_MODULE, 0, &card);
>>> - if (err < 0)
>>> - return err;
>>> -
>>> - uac2->card = card;
>>> -
>>> - /*
>>> - * Create first PCM device
>>> - * Create a substream only for non-zero channel streams
>>> - */
>>> - err = snd_pcm_new(uac2->card, "UAC2 PCM", 0,
>>> - p_chmask ? 1 : 0, c_chmask ? 1 : 0, &pcm);
>>> - if (err < 0)
>>> - goto snd_fail;
>>> -
>>> - strcpy(pcm->name, "UAC2 PCM");
>>> - pcm->private_data = uac2;
>>> -
>>> - uac2->pcm = pcm;
>>> -
>>> - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &uac2_pcm_ops);
>>> - snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &uac2_pcm_ops);
>>> -
>>> - strcpy(card->driver, "UAC2_Gadget");
>>> - strcpy(card->shortname, "UAC2_Gadget");
>>> - sprintf(card->longname, "UAC2_Gadget %i", card->dev->id);
>>> -
>>> - snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
>>> - snd_dma_continuous_data(GFP_KERNEL), 0, BUFF_SIZE_MAX);
>>> -
>>> - err = snd_card_register(card);
>>> -
>>> - if (!err)
>>> - return 0;
>>> -
>>> -snd_fail:
>>> - snd_card_free(card);
>>> -
>>> - uac2->pcm = NULL;
>>> - uac2->card = NULL;
>>> -
>>> - return err;
>>> -}
>>> -
>>> -static int snd_uac2_remove(struct audio_dev *audio_dev)
>>> -{
>>> - struct snd_card *card = audio_dev->uac2.card;
>>> -
>>> - if (card)
>>> - return snd_card_free(card);
>>> -
>>> - return 0;
>>> -}
>>> -
>>> -
>>> /* --------- USB Function Interface ------------- */
>>>
>>> enum {
>>> @@ -886,32 +451,6 @@ struct cntrl_range_lay3 {
>>> __u32 dRES;
>>> } __packed;
>>>
>>> -static inline void
>>> -free_ep(struct uac2_rtd_params *prm, struct usb_ep *ep)
>>> -{
>>> - struct snd_uac2_chip *uac2 = prm->uac2;
>>> - struct audio_dev *agdev = uac2_to_agdev(uac2);
>>> - struct f_uac2_opts *uac2_opts = agdev_to_uac2_opts(agdev);
>>> - int i;
>>> -
>>> - if (!prm->ep_enabled)
>>> - return;
>>> -
>>> - prm->ep_enabled = false;
>>> -
>>> - for (i = 0; i < uac2_opts->req_number; i++) {
>>> - if (prm->ureq[i].req) {
>>> - usb_ep_dequeue(ep, prm->ureq[i].req);
>>> - usb_ep_free_request(ep, prm->ureq[i].req);
>>> - prm->ureq[i].req = NULL;
>>> - }
>>> - }
>>> -
>>> - if (usb_ep_disable(ep))
>>> - dev_err(uac2->card->dev,
>>> - "%s:%d Error!\n", __func__, __LINE__);
>>> -}
>>> -
>>> static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> struct usb_endpoint_descriptor *ep_desc,
>>> unsigned int factor, bool is_playback)
>>> @@ -938,12 +477,11 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> static int
>>> afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
>>> {
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> - struct snd_uac2_chip *uac2 = &agdev->uac2;
>>> + struct f_uac2 *uac2 = func_to_uac2(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> struct usb_composite_dev *cdev = cfg->cdev;
>>> struct usb_gadget *gadget = cdev->gadget;
>>> struct device *dev = &gadget->dev;
>>> - struct uac2_rtd_params *prm;
>>> struct f_uac2_opts *uac2_opts;
>>> struct usb_string *us;
>>> int ret;
>>> @@ -990,8 +528,8 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> return ret;
>>> }
>>> std_ac_if_desc.bInterfaceNumber = ret;
>>> - agdev->ac_intf = ret;
>>> - agdev->ac_alt = 0;
>>> + uac2->ac_intf = ret;
>>> + uac2->ac_alt = 0;
>>>
>>> ret = usb_interface_id(cfg, fn);
>>> if (ret < 0) {
>>> @@ -1000,8 +538,8 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> }
>>> std_as_out_if0_desc.bInterfaceNumber = ret;
>>> std_as_out_if1_desc.bInterfaceNumber = ret;
>>> - agdev->as_out_intf = ret;
>>> - agdev->as_out_alt = 0;
>>> + uac2->as_out_intf = ret;
>>> + uac2->as_out_alt = 0;
>>>
>>> ret = usb_interface_id(cfg, fn);
>>> if (ret < 0) {
>>> @@ -1010,8 +548,8 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> }
>>> std_as_in_if0_desc.bInterfaceNumber = ret;
>>> std_as_in_if1_desc.bInterfaceNumber = ret;
>>> - agdev->as_in_intf = ret;
>>> - agdev->as_in_alt = 0;
>>> + uac2->as_in_intf = ret;
>>> + uac2->as_in_alt = 0;
>>>
>>> agdev->out_ep = usb_ep_autoconfig(gadget, &fs_epout_desc);
>>> if (!agdev->out_ep) {
>>> @@ -1025,15 +563,17 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> return ret;
>>> }
>>>
>>> - uac2->p_prm.uac2 = uac2;
>>> - uac2->c_prm.uac2 = uac2;
>>> -
>>> /* Calculate wMaxPacketSize according to audio bandwidth */
>>> set_ep_max_packet_size(uac2_opts, &fs_epin_desc, 1000, true);
>>> set_ep_max_packet_size(uac2_opts, &fs_epout_desc, 1000, false);
>>> set_ep_max_packet_size(uac2_opts, &hs_epin_desc, 8000, true);
>>> set_ep_max_packet_size(uac2_opts, &hs_epout_desc, 8000, false);
>>>
>>> + agdev->in_ep_maxpsize = max(fs_epin_desc.wMaxPacketSize,
>>> + hs_epin_desc.wMaxPacketSize);
>>> + agdev->out_ep_maxpsize = max(fs_epout_desc.wMaxPacketSize,
>>> + hs_epout_desc.wMaxPacketSize);
>>> +
>>> hs_epout_desc.bEndpointAddress = fs_epout_desc.bEndpointAddress;
>>> hs_epin_desc.bEndpointAddress = fs_epin_desc.bEndpointAddress;
>>>
>>> @@ -1044,46 +584,18 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>>
>>> agdev->gadget = gadget;
>>>
>>> - prm = &agdev->uac2.c_prm;
>>> - prm->max_psize = hs_epout_desc.wMaxPacketSize;
>>> - prm->ureq = kcalloc(uac2_opts->req_number, sizeof(struct uac2_req),
>>> - GFP_KERNEL);
>>> - if (!prm->ureq) {
>>> - ret = -ENOMEM;
>>> - goto err_free_descs;
>>> - }
>>> - prm->rbuf = kcalloc(uac2_opts->req_number, prm->max_psize, GFP_KERNEL);
>>> - if (!prm->rbuf) {
>>> - prm->max_psize = 0;
>>> - ret = -ENOMEM;
>>> - goto err_free_descs;
>>> - }
>>> -
>>> - prm = &agdev->uac2.p_prm;
>>> - prm->max_psize = hs_epin_desc.wMaxPacketSize;
>>> - prm->ureq = kcalloc(uac2_opts->req_number, sizeof(struct uac2_req),
>>> - GFP_KERNEL);
>>> - if (!prm->ureq) {
>>> - ret = -ENOMEM;
>>> - goto err_free_descs;
>>> - }
>>> - prm->rbuf = kcalloc(uac2_opts->req_number, prm->max_psize, GFP_KERNEL);
>>> - if (!prm->rbuf) {
>>> - prm->max_psize = 0;
>>> - ret = -ENOMEM;
>>> - goto err_no_memory;
>>> - }
>>> -
>>> - ret = snd_uac2_probe(agdev);
>>> + agdev->params.p_chmask = uac2_opts->p_chmask;
>>> + agdev->params.p_srate = uac2_opts->p_srate;
>>> + agdev->params.p_ssize = uac2_opts->p_ssize;
>>> + agdev->params.c_chmask = uac2_opts->c_chmask;
>>> + agdev->params.c_srate = uac2_opts->c_srate;
>>> + agdev->params.c_ssize = uac2_opts->c_ssize;
>>> + agdev->params.req_number = uac2_opts->req_number;
>>> + ret = g_audio_setup(agdev, "UAC2 PCM", "UAC2_Gadget");
>>> if (ret)
>>> - goto err_no_memory;
>>> + goto err_free_descs;
>>> return 0;
>>>
>>> -err_no_memory:
>>> - kfree(agdev->uac2.p_prm.ureq);
>>> - kfree(agdev->uac2.c_prm.ureq);
>>> - kfree(agdev->uac2.p_prm.rbuf);
>>> - kfree(agdev->uac2.c_prm.rbuf);
>>> err_free_descs:
>>> usb_free_all_descriptors(fn);
>>> agdev->gadget = NULL;
>>> @@ -1094,15 +606,10 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt)
>>> {
>>> struct usb_composite_dev *cdev = fn->config->cdev;
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> - struct f_uac2_opts *opts = agdev_to_uac2_opts(agdev);
>>> - struct snd_uac2_chip *uac2 = &agdev->uac2;
>>> + struct f_uac2 *uac2 = func_to_uac2(fn);
>>> struct usb_gadget *gadget = cdev->gadget;
>>> struct device *dev = &gadget->dev;
>>> - struct usb_request *req;
>>> - struct usb_ep *ep;
>>> - struct uac2_rtd_params *prm;
>>> - int req_len, i;
>>> + int ret = 0;
>>>
>>> /* No i/f has more than 2 alt settings */
>>> if (alt > 1) {
>>> @@ -1110,7 +617,7 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> return -EINVAL;
>>> }
>>>
>>> - if (intf == agdev->ac_intf) {
>>> + if (intf == uac2->ac_intf) {
>>> /* Control I/f has only 1 AltSetting - 0 */
>>> if (alt) {
>>> dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
>>> @@ -1119,92 +626,40 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> return 0;
>>> }
>>>
>>> - if (intf == agdev->as_out_intf) {
>>> - ep = agdev->out_ep;
>>> - prm = &uac2->c_prm;
>>> - config_ep_by_speed(gadget, fn, ep);
>>> - agdev->as_out_alt = alt;
>>> - req_len = prm->max_psize;
>>> - } else if (intf == agdev->as_in_intf) {
>>> - unsigned int factor, rate;
>>> - struct usb_endpoint_descriptor *ep_desc;
>>> -
>>> - ep = agdev->in_ep;
>>> - prm = &uac2->p_prm;
>>> - config_ep_by_speed(gadget, fn, ep);
>>> - agdev->as_in_alt = alt;
>>> -
>>> - /* pre-calculate the playback endpoint's interval */
>>> - if (gadget->speed == USB_SPEED_FULL) {
>>> - ep_desc = &fs_epin_desc;
>>> - factor = 1000;
>>> - } else {
>>> - ep_desc = &hs_epin_desc;
>>> - factor = 8000;
>>> - }
>>> -
>>> - /* pre-compute some values for iso_complete() */
>>> - uac2->p_framesize = opts->p_ssize *
>>> - num_channels(opts->p_chmask);
>>> - rate = opts->p_srate * uac2->p_framesize;
>>> - uac2->p_interval = factor / (1 << (ep_desc->bInterval - 1));
>>> - uac2->p_pktsize = min_t(unsigned int, rate / uac2->p_interval,
>>> - prm->max_psize);
>>> + if (intf == uac2->as_out_intf) {
>>> + uac2->as_out_alt = alt;
>>>
>>> - if (uac2->p_pktsize < prm->max_psize)
>>> - uac2->p_pktsize_residue = rate % uac2->p_interval;
>>> + if (alt)
>>> + ret = u_audio_start_capture(&uac2->g_audio);
>>> else
>>> - uac2->p_pktsize_residue = 0;
>>> + u_audio_stop_capture(&uac2->g_audio);
>>> + } else if (intf == uac2->as_in_intf) {
>>> + uac2->as_in_alt = alt;
>>>
>>> - req_len = uac2->p_pktsize;
>>> - uac2->p_residue = 0;
>>> + if (alt)
>>> + ret = u_audio_start_playback(&uac2->g_audio);
>>> + else
>>> + u_audio_stop_playback(&uac2->g_audio);
>>> } else {
>>> dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
>>> return -EINVAL;
>>> }
>>>
>>> - if (alt == 0) {
>>> - free_ep(prm, ep);
>>> - return 0;
>>> - }
>>> -
>>> - prm->ep_enabled = true;
>>> - usb_ep_enable(ep);
>>> -
>>> - for (i = 0; i < opts->req_number; i++) {
>>> - if (!prm->ureq[i].req) {
>>> - req = usb_ep_alloc_request(ep, GFP_ATOMIC);
>>> - if (req == NULL)
>>> - return -ENOMEM;
>>> -
>>> - prm->ureq[i].req = req;
>>> - prm->ureq[i].pp = prm;
>>> -
>>> - req->zero = 0;
>>> - req->context = &prm->ureq[i];
>>> - req->length = req_len;
>>> - req->complete = agdev_iso_complete;
>>> - req->buf = prm->rbuf + i * prm->max_psize;
>>> - }
>>> -
>>> - if (usb_ep_queue(ep, prm->ureq[i].req, GFP_ATOMIC))
>>> - dev_err(dev, "%s:%d Error!\n", __func__, __LINE__);
>>> - }
>>> -
>>> - return 0;
>>> + return ret;
>>> }
>>>
>>> static int
>>> afunc_get_alt(struct usb_function *fn, unsigned intf)
>>> {
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> -
>>> - if (intf == agdev->ac_intf)
>>> - return agdev->ac_alt;
>>> - else if (intf == agdev->as_out_intf)
>>> - return agdev->as_out_alt;
>>> - else if (intf == agdev->as_in_intf)
>>> - return agdev->as_in_alt;
>>> + struct f_uac2 *uac2 = func_to_uac2(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> +
>>> + if (intf == uac2->ac_intf)
>>> + return uac2->ac_alt;
>>> + else if (intf == uac2->as_out_intf)
>>> + return uac2->as_out_alt;
>>> + else if (intf == uac2->as_in_intf)
>>> + return uac2->as_in_alt;
>>> else
>>> dev_err(&agdev->gadget->dev,
>>> "%s:%d Invalid Interface %d!\n",
>>> @@ -1216,21 +671,19 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> static void
>>> afunc_disable(struct usb_function *fn)
>>> {
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> - struct snd_uac2_chip *uac2 = &agdev->uac2;
>>> -
>>> - free_ep(&uac2->p_prm, agdev->in_ep);
>>> - agdev->as_in_alt = 0;
>>> + struct f_uac2 *uac2 = func_to_uac2(fn);
>>>
>>> - free_ep(&uac2->c_prm, agdev->out_ep);
>>> - agdev->as_out_alt = 0;
>>> + uac2->as_in_alt = 0;
>>> + uac2->as_out_alt = 0;
>>> + u_audio_stop_capture(&uac2->g_audio);
>>> + u_audio_stop_playback(&uac2->g_audio);
>>> }
>>>
>>> static int
>>> in_rq_cur(struct usb_function *fn, const struct usb_ctrlrequest *cr)
>>> {
>>> struct usb_request *req = fn->config->cdev->req;
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> struct f_uac2_opts *opts;
>>> u16 w_length = le16_to_cpu(cr->wLength);
>>> u16 w_index = le16_to_cpu(cr->wIndex);
>>> @@ -1240,7 +693,7 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> int value = -EOPNOTSUPP;
>>> int p_srate, c_srate;
>>>
>>> - opts = agdev_to_uac2_opts(agdev);
>>> + opts = g_audio_to_uac2_opts(agdev);
>>> p_srate = opts->p_srate;
>>> c_srate = opts->c_srate;
>>>
>>> @@ -1271,7 +724,7 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> in_rq_range(struct usb_function *fn, const struct usb_ctrlrequest *cr)
>>> {
>>> struct usb_request *req = fn->config->cdev->req;
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> struct f_uac2_opts *opts;
>>> u16 w_length = le16_to_cpu(cr->wLength);
>>> u16 w_index = le16_to_cpu(cr->wIndex);
>>> @@ -1282,7 +735,7 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> int value = -EOPNOTSUPP;
>>> int p_srate, c_srate;
>>>
>>> - opts = agdev_to_uac2_opts(agdev);
>>> + opts = g_audio_to_uac2_opts(agdev);
>>> p_srate = opts->p_srate;
>>> c_srate = opts->c_srate;
>>>
>>> @@ -1336,11 +789,12 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> static int
>>> setup_rq_inf(struct usb_function *fn, const struct usb_ctrlrequest *cr)
>>> {
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> + struct f_uac2 *uac2 = func_to_uac2(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> u16 w_index = le16_to_cpu(cr->wIndex);
>>> u8 intf = w_index & 0xff;
>>>
>>> - if (intf != agdev->ac_intf) {
>>> + if (intf != uac2->ac_intf) {
>>> dev_err(&agdev->gadget->dev,
>>> "%s:%d Error!\n", __func__, __LINE__);
>>> return -EOPNOTSUPP;
>>> @@ -1358,7 +812,7 @@ static void set_ep_max_packet_size(const struct f_uac2_opts *uac2_opts,
>>> afunc_setup(struct usb_function *fn, const struct usb_ctrlrequest *cr)
>>> {
>>> struct usb_composite_dev *cdev = fn->config->cdev;
>>> - struct audio_dev *agdev = func_to_agdev(fn);
>>> + struct g_audio *agdev = func_to_g_audio(fn);
>>> struct usb_request *req = cdev->req;
>>> u16 w_length = le16_to_cpu(cr->wLength);
>>> int value = -EOPNOTSUPP;
>>> @@ -1504,10 +958,10 @@ static struct usb_function_instance *afunc_alloc_inst(void)
>>>
>>> static void afunc_free(struct usb_function *f)
>>> {
>>> - struct audio_dev *agdev;
>>> + struct g_audio *agdev;
>>> struct f_uac2_opts *opts;
>>>
>>> - agdev = func_to_agdev(f);
>>> + agdev = func_to_g_audio(f);
>>> opts = container_of(f->fi, struct f_uac2_opts, func_inst);
>>> kfree(agdev);
>>> mutex_lock(&opts->lock);
>>> @@ -1517,17 +971,9 @@ static void afunc_free(struct usb_function *f)
>>>
>>> static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
>>> {
>>> - struct audio_dev *agdev = func_to_agdev(f);
>>> - struct uac2_rtd_params *prm;
>>> -
>>> - snd_uac2_remove(agdev);
>>> -
>>> - prm = &agdev->uac2.p_prm;
>>> - kfree(prm->rbuf);
>>> + struct g_audio *agdev = func_to_g_audio(f);
>>>
>>> - prm = &agdev->uac2.c_prm;
>>> - kfree(prm->rbuf);
>>> - kfree(prm->ureq);
>>> + g_audio_cleanup(agdev);
>>> usb_free_all_descriptors(f);
>>>
>>> agdev->gadget = NULL;
>>> @@ -1535,11 +981,11 @@ static void afunc_unbind(struct usb_configuration *c, struct usb_function *f)
>>>
>>> static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
>>> {
>>> - struct audio_dev *agdev;
>>> + struct f_uac2 *uac2;
>>> struct f_uac2_opts *opts;
>>>
>>> - agdev = kzalloc(sizeof(*agdev), GFP_KERNEL);
>>> - if (agdev == NULL)
>>> + uac2 = kzalloc(sizeof(*uac2), GFP_KERNEL);
>>> + if (uac2 == NULL)
>>> return ERR_PTR(-ENOMEM);
>>>
>>> opts = container_of(fi, struct f_uac2_opts, func_inst);
>>> @@ -1547,19 +993,20 @@ static struct usb_function *afunc_alloc(struct usb_function_instance *fi)
>>> ++opts->refcnt;
>>> mutex_unlock(&opts->lock);
>>>
>>> - agdev->func.name = "uac2_func";
>>> - agdev->func.bind = afunc_bind;
>>> - agdev->func.unbind = afunc_unbind;
>>> - agdev->func.set_alt = afunc_set_alt;
>>> - agdev->func.get_alt = afunc_get_alt;
>>> - agdev->func.disable = afunc_disable;
>>> - agdev->func.setup = afunc_setup;
>>> - agdev->func.free_func = afunc_free;
>>> + uac2->g_audio.func.name = "uac2_func";
>>> + uac2->g_audio.func.bind = afunc_bind;
>>> + uac2->g_audio.func.unbind = afunc_unbind;
>>> + uac2->g_audio.func.set_alt = afunc_set_alt;
>>> + uac2->g_audio.func.get_alt = afunc_get_alt;
>>> + uac2->g_audio.func.disable = afunc_disable;
>>> + uac2->g_audio.func.setup = afunc_setup;
>>> + uac2->g_audio.func.free_func = afunc_free;
>>>
>>> - return &agdev->func;
>>> + return &uac2->g_audio.func;
>>> }
>>>
>>> DECLARE_USB_FUNCTION_INIT(uac2, afunc_alloc_inst, afunc_alloc);
>>> MODULE_LICENSE("GPL");
>>> MODULE_AUTHOR("Yadwinder Singh");
>>> MODULE_AUTHOR("Jaswinder Singh");
>>> +MODULE_AUTHOR("Ruslan Bilovol");
>>>
>> drivers/usb/gadget/function/f_uac2.c | 721 ++++------------------------------
>>
>> Basically you move out ALSA sound card implementation and %s/agdev/uac2/
>> I am not sure churn warrants a MODULE_AUTHOR. People have made far
>> more important contribution to the UAC2,
>
> Yes, I added it after cumulative effect of this patch and patch 1/3
> where I removed platform driver/device creation from f_uac2.
> I haven't find any rules on this and just counted changed lines,
> however in this particular case it's better to use something
> like MODULE_CLEANER(). Just joking :)
>
> I'll remove this line then.
>
Thanks, that will be fair to all.
>>
>>
>>> diff --git a/drivers/usb/gadget/function/u_audio.c b/drivers/usb/gadget/function/u_audio.c
>>> new file mode 100644
>>> index 0000000..8ee65b8
>>> --- /dev/null
>>> +++ b/drivers/usb/gadget/function/u_audio.c
>>> @@ -0,0 +1,661 @@
>>> +/*
>>> + * u_audio.c -- interface to USB gadget "ALSA sound card" utilities
>>> + *
>>> + * Copyright (C) 2016
>>> + * Author: Ruslan Bilovol <ruslan.bilovol@xxxxxxxxx>
>>> + *
>>> + * Based on f_uac2.c which is:
>>> + * Copyright (C) 2011
>>> + * Yadwinder Singh (yadi.brar01@xxxxxxxxx)
>>> + * Jaswinder Singh (jaswinder.singh@xxxxxxxxxx)
>>> + *
>> Again this is not "based on", rather where you paste the code you cut
>> from f_uac2.c
>> Of course you also pad it with minor changes to make it useful to your
>> uac1 code. I am not happy with losing copyright on the sound card
>> implementation for the UAC drivers.
>
> I don't remember why I wrote it as "based on" back in 2016,
> probably looking into another patches as example. As per my
> understanding, "based on" + your name in Copyright means
> that you still continue to hold copyright on the sound card
> implementation (otherwise why mention it?).
>
I don't think copyright spreads by inspiration :)
But seriously, we have to be careful if we set a precedence here. You
write some important piece of code and assert copyright over it.
Sometime later someone finds a reason to move that code to a new file
and adds his/her copyright while relegating you to just "inspiration".
You can contest the code was your copyright originally but is surely
tougher than having the code clearly state that fact.
> However I'm not a lawyer so can't say for sure.
> Will change this description in next patchset to make it clear,
> so you won't loose your copyright.
>
Thank you.