linux/sound/firewire/amdtp-stream.h
Takashi Iwai 2b3d2987d8 ALSA: firewire: Replace tasklet with work
The tasklet is an old API that should be deprecated, usually can be
converted to another decent API.  In FireWire driver, a tasklet is
still used for offloading the AMDTP PCM stream handling.  It can be
achieved gracefully with a work queued, too.

This patch replaces the tasklet usage in firewire-lib driver with a
simple work.  The conversion is fairly straightforward but for the
in_interrupt() checks that are replaced with the check using the
current_work().

Note that in_interrupt() in amdtp_packet tracepoint is still kept as
is.  This is the place that is probed by both softirq of 1394 OHCI and
a user task of a PCM application, and the work handling is already
filtered in amdtp_domain_stream_pcm_pointer().

Tested-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200909163659.21708-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-09-11 18:22:54 +02:00

323 lines
9.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef SOUND_FIREWIRE_AMDTP_H_INCLUDED
#define SOUND_FIREWIRE_AMDTP_H_INCLUDED
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/sched.h>
#include <sound/asound.h>
#include "packets-buffer.h"
/**
* enum cip_flags - describes details of the streaming protocol
* @CIP_NONBLOCKING: In non-blocking mode, each packet contains
* sample_rate/8000 samples, with rounding up or down to adjust
* for clock skew and left-over fractional samples. This should
* be used if supported by the device.
* @CIP_BLOCKING: In blocking mode, each packet contains either zero or
* SYT_INTERVAL samples, with these two types alternating so that
* the overall sample rate comes out right.
* @CIP_EMPTY_WITH_TAG0: Only for in-stream. Empty in-packets have TAG0.
* @CIP_DBC_IS_END_EVENT: The value of dbc in an packet corresponds to the end
* of event in the packet. Out of IEC 61883.
* @CIP_WRONG_DBS: Only for in-stream. The value of dbs is wrong in in-packets.
* The value of data_block_quadlets is used instead of reported value.
* @CIP_SKIP_DBC_ZERO_CHECK: Only for in-stream. Packets with zero in dbc is
* skipped for detecting discontinuity.
* @CIP_EMPTY_HAS_WRONG_DBC: Only for in-stream. The value of dbc in empty
* packet is wrong but the others are correct.
* @CIP_JUMBO_PAYLOAD: Only for in-stream. The number of data blocks in an
* packet is larger than IEC 61883-6 defines. Current implementation
* allows 5 times as large as IEC 61883-6 defines.
* @CIP_HEADER_WITHOUT_EOH: Only for in-stream. CIP Header doesn't include
* valid EOH.
* @CIP_NO_HEADERS: a lack of headers in packets
* @CIP_UNALIGHED_DBC: Only for in-stream. The value of dbc is not alighed to
* the value of current SYT_INTERVAL; e.g. initial value is not zero.
*/
enum cip_flags {
CIP_NONBLOCKING = 0x00,
CIP_BLOCKING = 0x01,
CIP_EMPTY_WITH_TAG0 = 0x02,
CIP_DBC_IS_END_EVENT = 0x04,
CIP_WRONG_DBS = 0x08,
CIP_SKIP_DBC_ZERO_CHECK = 0x10,
CIP_EMPTY_HAS_WRONG_DBC = 0x20,
CIP_JUMBO_PAYLOAD = 0x40,
CIP_HEADER_WITHOUT_EOH = 0x80,
CIP_NO_HEADER = 0x100,
CIP_UNALIGHED_DBC = 0x200,
};
/**
* enum cip_sfc - supported Sampling Frequency Codes (SFCs)
* @CIP_SFC_32000: 32,000 data blocks
* @CIP_SFC_44100: 44,100 data blocks
* @CIP_SFC_48000: 48,000 data blocks
* @CIP_SFC_88200: 88,200 data blocks
* @CIP_SFC_96000: 96,000 data blocks
* @CIP_SFC_176400: 176,400 data blocks
* @CIP_SFC_192000: 192,000 data blocks
* @CIP_SFC_COUNT: the number of supported SFCs
*
* These values are used to show nominal Sampling Frequency Code in
* Format Dependent Field (FDF) of AMDTP packet header. In IEC 61883-6:2002,
* this code means the number of events per second. Actually the code
* represents the number of data blocks transferred per second in an AMDTP
* stream.
*
* In IEC 61883-6:2005, some extensions were added to support more types of
* data such as 'One Bit LInear Audio', therefore the meaning of SFC became
* different depending on the types.
*
* Currently our implementation is compatible with IEC 61883-6:2002.
*/
enum cip_sfc {
CIP_SFC_32000 = 0,
CIP_SFC_44100 = 1,
CIP_SFC_48000 = 2,
CIP_SFC_88200 = 3,
CIP_SFC_96000 = 4,
CIP_SFC_176400 = 5,
CIP_SFC_192000 = 6,
CIP_SFC_COUNT
};
struct fw_unit;
struct fw_iso_context;
struct snd_pcm_substream;
struct snd_pcm_runtime;
enum amdtp_stream_direction {
AMDTP_OUT_STREAM = 0,
AMDTP_IN_STREAM
};
struct pkt_desc {
u32 cycle;
u32 syt;
unsigned int data_blocks;
unsigned int data_block_counter;
__be32 *ctx_payload;
};
struct amdtp_stream;
typedef unsigned int (*amdtp_stream_process_ctx_payloads_t)(
struct amdtp_stream *s,
const struct pkt_desc *desc,
unsigned int packets,
struct snd_pcm_substream *pcm);
struct amdtp_domain;
struct amdtp_stream {
struct fw_unit *unit;
enum cip_flags flags;
enum amdtp_stream_direction direction;
struct mutex mutex;
/* For packet processing. */
struct fw_iso_context *context;
struct iso_packets_buffer buffer;
unsigned int queue_size;
int packet_index;
struct pkt_desc *pkt_descs;
int tag;
union {
struct {
unsigned int ctx_header_size;
// limit for payload of iso packet.
unsigned int max_ctx_payload_length;
// For quirks of CIP headers.
// Fixed interval of dbc between previos/current
// packets.
unsigned int dbc_interval;
} tx;
struct {
// To calculate CIP data blocks and tstamp.
unsigned int transfer_delay;
unsigned int seq_index;
// To generate CIP header.
unsigned int fdf;
int syt_override;
// To generate constant hardware IRQ.
unsigned int event_count;
unsigned int events_per_period;
} rx;
} ctx_data;
/* For CIP headers. */
unsigned int source_node_id_field;
unsigned int data_block_quadlets;
unsigned int data_block_counter;
unsigned int sph;
unsigned int fmt;
/* Internal flags. */
enum cip_sfc sfc;
unsigned int syt_interval;
/* For a PCM substream processing. */
struct snd_pcm_substream *pcm;
struct work_struct period_work;
snd_pcm_uframes_t pcm_buffer_pointer;
unsigned int pcm_period_pointer;
/* To wait for first packet. */
bool callbacked;
wait_queue_head_t callback_wait;
u32 start_cycle;
/* For backends to process data blocks. */
void *protocol;
amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
// For domain.
int channel;
int speed;
struct list_head list;
struct amdtp_domain *domain;
};
int amdtp_stream_init(struct amdtp_stream *s, struct fw_unit *unit,
enum amdtp_stream_direction dir, enum cip_flags flags,
unsigned int fmt,
amdtp_stream_process_ctx_payloads_t process_ctx_payloads,
unsigned int protocol_size);
void amdtp_stream_destroy(struct amdtp_stream *s);
int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate,
unsigned int data_block_quadlets);
unsigned int amdtp_stream_get_max_payload(struct amdtp_stream *s);
void amdtp_stream_update(struct amdtp_stream *s);
int amdtp_stream_add_pcm_hw_constraints(struct amdtp_stream *s,
struct snd_pcm_runtime *runtime);
void amdtp_stream_pcm_prepare(struct amdtp_stream *s);
void amdtp_stream_pcm_abort(struct amdtp_stream *s);
extern const unsigned int amdtp_syt_intervals[CIP_SFC_COUNT];
extern const unsigned int amdtp_rate_table[CIP_SFC_COUNT];
/**
* amdtp_stream_running - check stream is running or not
* @s: the AMDTP stream
*
* If this function returns true, the stream is running.
*/
static inline bool amdtp_stream_running(struct amdtp_stream *s)
{
return !IS_ERR(s->context);
}
/**
* amdtp_streaming_error - check for streaming error
* @s: the AMDTP stream
*
* If this function returns true, the stream's packet queue has stopped due to
* an asynchronous error.
*/
static inline bool amdtp_streaming_error(struct amdtp_stream *s)
{
return s->packet_index < 0;
}
/**
* amdtp_stream_pcm_running - check PCM substream is running or not
* @s: the AMDTP stream
*
* If this function returns true, PCM substream in the AMDTP stream is running.
*/
static inline bool amdtp_stream_pcm_running(struct amdtp_stream *s)
{
return !!s->pcm;
}
/**
* amdtp_stream_pcm_trigger - start/stop playback from a PCM device
* @s: the AMDTP stream
* @pcm: the PCM device to be started, or %NULL to stop the current device
*
* Call this function on a running isochronous stream to enable the actual
* transmission of PCM data. This function should be called from the PCM
* device's .trigger callback.
*/
static inline void amdtp_stream_pcm_trigger(struct amdtp_stream *s,
struct snd_pcm_substream *pcm)
{
WRITE_ONCE(s->pcm, pcm);
}
static inline bool cip_sfc_is_base_44100(enum cip_sfc sfc)
{
return sfc & 1;
}
/**
* amdtp_stream_wait_callback - sleep till callbacked or timeout
* @s: the AMDTP stream
* @timeout: msec till timeout
*
* If this function return false, the AMDTP stream should be stopped.
*/
static inline bool amdtp_stream_wait_callback(struct amdtp_stream *s,
unsigned int timeout)
{
return wait_event_timeout(s->callback_wait,
s->callbacked == true,
msecs_to_jiffies(timeout)) > 0;
}
struct seq_desc {
unsigned int syt_offset;
unsigned int data_blocks;
};
struct amdtp_domain {
struct list_head streams;
unsigned int events_per_period;
unsigned int events_per_buffer;
struct amdtp_stream *irq_target;
struct seq_desc *seq_descs;
unsigned int seq_size;
unsigned int seq_tail;
unsigned int data_block_state;
unsigned int syt_offset_state;
unsigned int last_syt_offset;
};
int amdtp_domain_init(struct amdtp_domain *d);
void amdtp_domain_destroy(struct amdtp_domain *d);
int amdtp_domain_add_stream(struct amdtp_domain *d, struct amdtp_stream *s,
int channel, int speed);
int amdtp_domain_start(struct amdtp_domain *d, unsigned int ir_delay_cycle);
void amdtp_domain_stop(struct amdtp_domain *d);
static inline int amdtp_domain_set_events_per_period(struct amdtp_domain *d,
unsigned int events_per_period,
unsigned int events_per_buffer)
{
d->events_per_period = events_per_period;
d->events_per_buffer = events_per_buffer;
return 0;
}
unsigned long amdtp_domain_stream_pcm_pointer(struct amdtp_domain *d,
struct amdtp_stream *s);
int amdtp_domain_stream_pcm_ack(struct amdtp_domain *d, struct amdtp_stream *s);
#endif