From: Šerif Rami Date: Thu, 14 Aug 2025 17:22:17 +0000 (+0200) Subject: ALSA: usb-audio: us144mkii: Add PCM core infrastructure X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=5c8c10796e274d1b5bb48756a45a6f2e865b30f2;p=users%2Fhch%2Fmisc.git ALSA: usb-audio: us144mkii: Add PCM core infrastructure This patch adds the ALSA PCM device infrastructure. It creates a new PCM device with one playback and one capture stream. The hardware capabilities (formats, rates, channels) are defined in `tascam_pcm_hw`. The core PCM operations (`snd_pcm_ops`) for both playback and capture are implemented, including open, close, hw_params, prepare, and pointer callbacks. The trigger callback is a stub for now. This commit allows user-space applications to interact with the ALSA device, but no audio will be streamed yet. Signed-off-by: Šerif Rami Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250814172222.9448-3-ramiserifpersia@gmail.com --- diff --git a/sound/usb/usx2y/us144mkii.c b/sound/usb/usx2y/us144mkii.c index 00d13b039589..a41f48fe2bee 100644 --- a/sound/usb/usx2y/us144mkii.c +++ b/sound/usb/usx2y/us144mkii.c @@ -22,7 +22,7 @@ MODULE_LICENSE("GPL"); * Defaults to "US144MKII". * @param enable: Array of booleans to enable or disable each device. * Defaults to {1, 0, ..., 0} (first device enabled). - * @param dev_idx: Internal counter for probed TASCAM devices. + * @param dev_idx: Internal counter for the number of TASCAM devices probed. */ static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX; static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR; @@ -36,7 +36,7 @@ static int tascam_suspend(struct usb_interface *intf, pm_message_t message); static int tascam_resume(struct usb_interface *intf); /** - * tascam_card_private_free() - Frees private data for the sound card. + * tascam_card_private_free() - Frees private data associated with the sound * card. * @card: Pointer to the ALSA sound card instance. * @@ -58,12 +58,12 @@ static void tascam_card_private_free(struct snd_card *card) * @intf: The USB interface being probed. * @usb_id: The USB device ID. * - * This function is the entry point for the USB driver on device match. + * This function is the entry point for the USB driver when a matching device * is found. It performs initial device setup, including: * - Checking for the second interface (MIDI) and associating it. * - Performing a vendor-specific handshake with the device. * - Setting alternate settings for USB interfaces. - * - Creating and registering the ALSA sound card. + * - Creating and registering the ALSA sound card and PCM device. * * Return: 0 on success, or a negative error code on failure. */ @@ -154,6 +154,18 @@ static int tascam_probe(struct usb_interface *intf, tascam->digital_out_source = 1; tascam->capture_34_source = 1; + spin_lock_init(&tascam->lock); + + err = snd_pcm_new(card, "US144MKII PCM", 0, 1, 1, &tascam->pcm); + if (err < 0) + goto free_card; + tascam->pcm->private_data = tascam; + strscpy(tascam->pcm->name, "US144MKII PCM", sizeof(tascam->pcm->name)); + + err = tascam_init_pcm(tascam->pcm); + if (err < 0) + goto free_card; + strscpy(card->driver, DRIVER_NAME, sizeof(card->driver)); if (dev->descriptor.idProduct == USB_PID_TASCAM_US144) { strscpy(card->shortname, "TASCAM US-144", diff --git a/sound/usb/usx2y/us144mkii.h b/sound/usb/usx2y/us144mkii.h index 9f59863fab57..44f3b44bbf3b 100644 --- a/sound/usb/usx2y/us144mkii.h +++ b/sound/usb/usx2y/us144mkii.h @@ -21,18 +21,60 @@ #define MODE_VAL_HANDSHAKE_READ 0x0000 #define USB_CTRL_TIMEOUT_MS 1000 +/* --- Audio Format Configuration --- */ +#define BYTES_PER_SAMPLE 3 +#define NUM_CHANNELS 4 +#define BYTES_PER_FRAME (NUM_CHANNELS * BYTES_PER_SAMPLE) + +/* --- USB Control Message Protocol --- */ +#define RT_D2H_VENDOR_DEV (USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE) +#define VENDOR_REQ_MODE_CONTROL 0x49 +#define MODE_VAL_HANDSHAKE_READ 0x0000 +#define USB_CTRL_TIMEOUT_MS 1000 + +struct tascam_card; + +#include "us144mkii_pcm.h" + /** - * struct tascam_card - Driver data structure for TASCAM US-144MKII. + * struct tascam_card - Main driver data structure for the TASCAM US-144MKII. * @dev: Pointer to the USB device. * @iface0: Pointer to USB interface 0 (audio). * @iface1: Pointer to USB interface 1 (MIDI). * @card: Pointer to the ALSA sound card instance. + * @pcm: Pointer to the ALSA PCM device. + * @playback_substream: Pointer to the active playback PCM substream. + * @capture_substream: Pointer to the active capture PCM substream. + * @playback_active: Atomic flag indicating if playback is active. + * @capture_active: Atomic flag indicating if capture is active. + * @driver_playback_pos: Current position in the ALSA playback buffer (frames). + * @driver_capture_pos: Current position in the ALSA capture buffer (frames). + * @playback_frames_consumed: Total frames consumed by playback. + * @capture_frames_processed: Total frames processed for capture. + * @current_rate: Currently configured sample rate of the device. + * @lock: Main spinlock for protecting shared driver state. */ struct tascam_card { struct usb_device *dev; struct usb_interface *iface0; struct usb_interface *iface1; struct snd_card *card; + struct snd_pcm *pcm; + + struct snd_pcm_substream *playback_substream; + struct snd_pcm_substream *capture_substream; + + atomic_t playback_active; + atomic_t capture_active; + + snd_pcm_uframes_t driver_playback_pos; + snd_pcm_uframes_t driver_capture_pos; + + u64 playback_frames_consumed; + u64 capture_frames_processed; + + int current_rate; + spinlock_t lock; }; - #endif /* __US144MKII_H */ +#endif /* __US144MKII_H */ diff --git a/sound/usb/usx2y/us144mkii_capture.c b/sound/usb/usx2y/us144mkii_capture.c new file mode 100644 index 000000000000..f258198ec94b --- /dev/null +++ b/sound/usb/usx2y/us144mkii_capture.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2025 Å erif Rami + +#include "us144mkii.h" + +/** + * tascam_capture_open() - Opens the PCM capture substream. + * @substream: The ALSA PCM substream to open. + * + * This function sets the hardware parameters for the capture substream + * and stores a reference to the substream in the driver's private data. + * + * Return: 0 on success. + */ +static int tascam_capture_open(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + substream->runtime->hw = tascam_pcm_hw; + tascam->capture_substream = substream; + atomic_set(&tascam->capture_active, 0); + + return 0; +} + +/** + * tascam_capture_close() - Closes the PCM capture substream. + * @substream: The ALSA PCM substream to close. + * + * This function clears the reference to the capture substream in the + * driver's private data. + * + * Return: 0 on success. + */ +static int tascam_capture_close(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + tascam->capture_substream = NULL; + + return 0; +} + +/** + * tascam_capture_prepare() - Prepares the PCM capture substream for use. + * @substream: The ALSA PCM substream to prepare. + * + * This function initializes capture-related counters. + * + * Return: 0 on success. + */ +static int tascam_capture_prepare(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + tascam->driver_capture_pos = 0; + tascam->capture_frames_processed = 0; + + return 0; +} + +/** + * tascam_capture_pointer() - Returns the current capture pointer position. + * @substream: The ALSA PCM substream. + * + * This function returns the current position of the capture pointer within + * the ALSA ring buffer, in frames. + * + * Return: The current capture pointer position in frames. + */ +static snd_pcm_uframes_t +tascam_capture_pointer(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + u64 pos; + + if (!atomic_read(&tascam->capture_active)) + return 0; + + scoped_guard(spinlock_irqsave, &tascam->lock) { + pos = tascam->capture_frames_processed; + } + + if (runtime->buffer_size == 0) + return 0; + + return do_div(pos, runtime->buffer_size); +} + +/** + * tascam_capture_ops - ALSA PCM operations for capture. + * + * This structure defines the callback functions for capture stream operations, + * including open, close, ioctl, hardware parameters, hardware free, prepare, + * trigger, and pointer. + */ +const struct snd_pcm_ops tascam_capture_ops = { + .open = tascam_capture_open, + .close = tascam_capture_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = tascam_pcm_hw_params, + .hw_free = tascam_pcm_hw_free, + .prepare = tascam_capture_prepare, + .trigger = tascam_pcm_trigger, + .pointer = tascam_capture_pointer, +}; diff --git a/sound/usb/usx2y/us144mkii_pcm.c b/sound/usb/usx2y/us144mkii_pcm.c new file mode 100644 index 000000000000..944b4d0ee2ec --- /dev/null +++ b/sound/usb/usx2y/us144mkii_pcm.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2025 Å erif Rami + +#include "us144mkii.h" + +const struct snd_pcm_hardware tascam_pcm_hw = { + .info = (SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_INTERLEAVED | + SNDRV_PCM_INFO_BLOCK_TRANSFER | SNDRV_PCM_INFO_MMAP_VALID | + SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME), + .formats = SNDRV_PCM_FMTBIT_S24_3LE, + .rates = (SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 | + SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000), + .rate_min = 44100, + .rate_max = 96000, + .channels_min = NUM_CHANNELS, + .channels_max = NUM_CHANNELS, + .buffer_bytes_max = 1024 * 1024, + .period_bytes_min = 48 * BYTES_PER_FRAME, + .period_bytes_max = 1024 * BYTES_PER_FRAME, + .periods_min = 2, + .periods_max = 1024, +}; + +int tascam_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params) +{ + return 0; +} + +int tascam_pcm_hw_free(struct snd_pcm_substream *substream) +{ + return 0; +} + +int tascam_pcm_trigger(struct snd_pcm_substream *substream, int cmd) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + int err = 0; + + scoped_guard(spinlock_irqsave, &tascam->lock) { + switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_RESUME: + if (!atomic_read(&tascam->playback_active)) { + atomic_set(&tascam->playback_active, 1); + atomic_set(&tascam->capture_active, 1); + } + break; + case SNDRV_PCM_TRIGGER_STOP: + case SNDRV_PCM_TRIGGER_SUSPEND: + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: + if (atomic_read(&tascam->playback_active)) { + atomic_set(&tascam->playback_active, 0); + atomic_set(&tascam->capture_active, 0); + } + break; + default: + err = -EINVAL; + break; + } + } + + return err; +} + +int tascam_init_pcm(struct snd_pcm *pcm) +{ + struct tascam_card *tascam = pcm->private_data; + + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &tascam_playback_ops); + snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &tascam_capture_ops); + + snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS, + tascam->dev->dev.parent, 64 * 1024, + tascam_pcm_hw.buffer_bytes_max); + + return 0; +} diff --git a/sound/usb/usx2y/us144mkii_pcm.h b/sound/usb/usx2y/us144mkii_pcm.h new file mode 100644 index 000000000000..bb8b51f9b6fb --- /dev/null +++ b/sound/usb/usx2y/us144mkii_pcm.h @@ -0,0 +1,76 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +// Copyright (c) 2025 Å erif Rami + +#ifndef __US144MKII_PCM_H +#define __US144MKII_PCM_H + +#include "us144mkii.h" + +/** + * tascam_pcm_hw - Hardware capabilities for TASCAM US-144MKII PCM. + * + * Defines the supported PCM formats, rates, channels, and buffer/period sizes + * for the TASCAM US-144MKII audio interface. + */ +extern const struct snd_pcm_hardware tascam_pcm_hw; + +/** + * tascam_playback_ops - ALSA PCM operations for playback. + * + * This structure defines the callback functions for playback stream operations. + */ +extern const struct snd_pcm_ops tascam_playback_ops; + +/** + * tascam_capture_ops - ALSA PCM operations for capture. + * + * This structure defines the callback functions for capture stream operations. + */ +extern const struct snd_pcm_ops tascam_capture_ops; + +/** + * tascam_init_pcm() - Initializes the ALSA PCM device. + * @pcm: Pointer to the ALSA PCM device to initialize. + * + * This function sets up the PCM operations and preallocates pages for the + * PCM buffer. + * + * Return: 0 on success, or a negative error code on failure. + */ +int tascam_init_pcm(struct snd_pcm *pcm); + +/** + * tascam_pcm_hw_params() - Configures hardware parameters for PCM streams. + * @substream: The ALSA PCM substream. + * @params: The hardware parameters to apply. + * + * This function is a stub for handling hardware parameter configuration. + * + * Return: 0 on success. + */ +int tascam_pcm_hw_params(struct snd_pcm_substream *substream, + struct snd_pcm_hw_params *params); + +/** + * tascam_pcm_hw_free() - Frees hardware parameters for PCM streams. + * @substream: The ALSA PCM substream. + * + * This function is a stub for freeing hardware-related resources. + * + * Return: 0 on success. + */ +int tascam_pcm_hw_free(struct snd_pcm_substream *substream); + +/** + * tascam_pcm_trigger() - Triggers the start or stop of PCM streams. + * @substream: The ALSA PCM substream. + * @cmd: The trigger command (e.g., SNDRV_PCM_TRIGGER_START). + * + * This function handles starting and stopping of playback and capture streams + * by setting atomic flags. + * + * Return: 0 on success, or a negative error code on failure. + */ +int tascam_pcm_trigger(struct snd_pcm_substream *substream, int cmd); + +#endif /* __US144MKII_PCM_H */ diff --git a/sound/usb/usx2y/us144mkii_playback.c b/sound/usb/usx2y/us144mkii_playback.c new file mode 100644 index 000000000000..0785c58f1197 --- /dev/null +++ b/sound/usb/usx2y/us144mkii_playback.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (c) 2025 Å erif Rami + +#include "us144mkii.h" + +/** + * tascam_playback_open() - Opens the PCM playback substream. + * @substream: The ALSA PCM substream to open. + * + * This function sets the hardware parameters for the playback substream + * and stores a reference to the substream in the driver's private data. + * + * Return: 0 on success. + */ +static int tascam_playback_open(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + substream->runtime->hw = tascam_pcm_hw; + tascam->playback_substream = substream; + atomic_set(&tascam->playback_active, 0); + + return 0; +} + +/** + * tascam_playback_close() - Closes the PCM playback substream. + * @substream: The ALSA PCM substream to close. + * + * This function clears the reference to the playback substream in the + * driver's private data. + * + * Return: 0 on success. + */ +static int tascam_playback_close(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + tascam->playback_substream = NULL; + + return 0; +} + +/** + * tascam_playback_prepare() - Prepares the PCM playback substream for use. + * @substream: The ALSA PCM substream to prepare. + * + * This function initializes playback-related counters. + * + * Return: 0 on success. + */ +static int tascam_playback_prepare(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + + tascam->driver_playback_pos = 0; + tascam->playback_frames_consumed = 0; + + return 0; +} + +/** + * tascam_playback_pointer() - Returns the current playback pointer position. + * @substream: The ALSA PCM substream. + * + * This function returns the current position of the playback pointer within + * the ALSA ring buffer, in frames. + * + * Return: The current playback pointer position in frames. + */ +static snd_pcm_uframes_t +tascam_playback_pointer(struct snd_pcm_substream *substream) +{ + struct tascam_card *tascam = snd_pcm_substream_chip(substream); + struct snd_pcm_runtime *runtime = substream->runtime; + u64 pos; + + if (!atomic_read(&tascam->playback_active)) + return 0; + + scoped_guard(spinlock_irqsave, &tascam->lock) { + pos = tascam->playback_frames_consumed; + } + + if (runtime->buffer_size == 0) + return 0; + + return do_div(pos, runtime->buffer_size); +} + +/** + * tascam_playback_ops - ALSA PCM operations for playback. + * + * This structure defines the callback functions for playback stream operations, + * including open, close, ioctl, hardware parameters, hardware free, prepare, + * trigger, and pointer. + */ +const struct snd_pcm_ops tascam_playback_ops = { + .open = tascam_playback_open, + .close = tascam_playback_close, + .ioctl = snd_pcm_lib_ioctl, + .hw_params = tascam_pcm_hw_params, + .hw_free = tascam_pcm_hw_free, + .prepare = tascam_playback_prepare, + .trigger = tascam_pcm_trigger, + .pointer = tascam_playback_pointer, +};