linux/drivers/soundwire/cadence_master.h
Ranjani Sridharan 8ddeafb957
soundwire: intel: improve suspend flows
This patch provides both a simplification of the suspend flows and a
better balanced operation during suspend/resume transition, as part of
the transition of Sound Open Firmware (SOF) to dynamic pipelines: the
DSP resources are only enabled when required instead of enabled on
startup.

The exiting code relies on a convoluted way of dealing with suspend
signals. Since there is no .suspend DAI callback, we used the
component .suspend and marked all the component DAI dmas as
'suspended'. The information was used in the .prepare stage to
differentiate resume operations from xrun handling, and only
reinitialize SHIM registers and DMA in the former case.

While this solution has been working reliably for about 2 years, there
is a much better solution consisting in trapping the TRIGGER_SUSPEND
in the .trigger DAI ops. The DMA is still marked in the same way for
the .prepare op to run, but in addition the callbacks sent to DSP
firmware are now balanced.

Normal operation:
hw_params -> intel_params_stream
hw_free   -> intel_free_stream

suspend    -> intel_free_stream
prepare    -> intel_params_stream

This balanced operation was not required with existing SOF firmware
relying on static pipelines instantiated at every boot. With the
on-going transition to dynamic pipelines, it's however a requirement
to keep the use count for the DAI widget balanced across all
transitions.

The component suspend is not removed but instead modified to deal with
a corner case: when a substream is PAUSED, the ALSA core does not
throw the TRIGGER_SUSPEND. This is problematic since the refcount for
all pipelines and widgets is not balanced, leading to issues on
resume. The trigger callback keeps track of the 'paused' state with a
new flag, which is tested during the component suspend called later to
release the remaining DSP resources. These resources will be
re-enabled in the .prepare step.

The IPC used in the TRIGGER_SUSPEND to release DSP resources is not a
problem since the BE dailink is already marked as non-atomic.

Co-developed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20211224021034.26635-4-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2021-12-24 14:06:46 +00:00

197 lines
5.1 KiB
C

/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */
/* Copyright(c) 2015-17 Intel Corporation. */
#include <sound/soc.h>
#ifndef __SDW_CADENCE_H
#define __SDW_CADENCE_H
#define SDW_CADENCE_GSYNC_KHZ 4 /* 4 kHz */
#define SDW_CADENCE_GSYNC_HZ (SDW_CADENCE_GSYNC_KHZ * 1000)
/**
* struct sdw_cdns_pdi: PDI (Physical Data Interface) instance
*
* @num: pdi number
* @intel_alh_id: link identifier
* @l_ch_num: low channel for PDI
* @h_ch_num: high channel for PDI
* @ch_count: total channel count for PDI
* @dir: data direction
* @type: stream type, PDM or PCM
*/
struct sdw_cdns_pdi {
int num;
int intel_alh_id;
int l_ch_num;
int h_ch_num;
int ch_count;
enum sdw_data_direction dir;
enum sdw_stream_type type;
};
/**
* struct sdw_cdns_streams: Cadence stream data structure
*
* @num_bd: number of bidirectional streams
* @num_in: number of input streams
* @num_out: number of output streams
* @num_ch_bd: number of bidirectional stream channels
* @num_ch_bd: number of input stream channels
* @num_ch_bd: number of output stream channels
* @num_pdi: total number of PDIs
* @bd: bidirectional streams
* @in: input streams
* @out: output streams
*/
struct sdw_cdns_streams {
unsigned int num_bd;
unsigned int num_in;
unsigned int num_out;
unsigned int num_ch_bd;
unsigned int num_ch_in;
unsigned int num_ch_out;
unsigned int num_pdi;
struct sdw_cdns_pdi *bd;
struct sdw_cdns_pdi *in;
struct sdw_cdns_pdi *out;
};
/**
* struct sdw_cdns_stream_config: stream configuration
*
* @pcm_bd: number of bidirectional PCM streams supported
* @pcm_in: number of input PCM streams supported
* @pcm_out: number of output PCM streams supported
* @pdm_bd: number of bidirectional PDM streams supported
* @pdm_in: number of input PDM streams supported
* @pdm_out: number of output PDM streams supported
*/
struct sdw_cdns_stream_config {
unsigned int pcm_bd;
unsigned int pcm_in;
unsigned int pcm_out;
unsigned int pdm_bd;
unsigned int pdm_in;
unsigned int pdm_out;
};
/**
* struct sdw_cdns_dma_data: Cadence DMA data
*
* @name: SoundWire stream name
* @stream: stream runtime
* @pdi: PDI used for this dai
* @bus: Bus handle
* @stream_type: Stream type
* @link_id: Master link id
* @hw_params: hw_params to be applied in .prepare step
* @suspended: status set when suspended, to be used in .prepare
* @paused: status set in .trigger, to be used in suspend
*/
struct sdw_cdns_dma_data {
char *name;
struct sdw_stream_runtime *stream;
struct sdw_cdns_pdi *pdi;
struct sdw_bus *bus;
enum sdw_stream_type stream_type;
int link_id;
struct snd_pcm_hw_params *hw_params;
bool suspended;
bool paused;
};
/**
* struct sdw_cdns - Cadence driver context
* @dev: Linux device
* @bus: Bus handle
* @instance: instance number
* @response_buf: SoundWire response buffer
* @tx_complete: Tx completion
* @defer: Defer pointer
* @ports: Data ports
* @num_ports: Total number of data ports
* @pcm: PCM streams
* @pdm: PDM streams
* @registers: Cadence registers
* @link_up: Link status
* @msg_count: Messages sent on bus
*/
struct sdw_cdns {
struct device *dev;
struct sdw_bus bus;
unsigned int instance;
u32 response_buf[0x80];
struct completion tx_complete;
struct sdw_defer *defer;
struct sdw_cdns_port *ports;
int num_ports;
struct sdw_cdns_streams pcm;
struct sdw_cdns_streams pdm;
int pdi_loopback_source;
int pdi_loopback_target;
void __iomem *registers;
bool link_up;
unsigned int msg_count;
bool interrupt_enabled;
struct work_struct work;
struct list_head list;
};
#define bus_to_cdns(_bus) container_of(_bus, struct sdw_cdns, bus)
/* Exported symbols */
int sdw_cdns_probe(struct sdw_cdns *cdns);
extern struct sdw_master_ops sdw_cdns_master_ops;
irqreturn_t sdw_cdns_irq(int irq, void *dev_id);
irqreturn_t sdw_cdns_thread(int irq, void *dev_id);
int sdw_cdns_init(struct sdw_cdns *cdns);
int sdw_cdns_pdi_init(struct sdw_cdns *cdns,
struct sdw_cdns_stream_config config);
int sdw_cdns_exit_reset(struct sdw_cdns *cdns);
int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns, bool state);
bool sdw_cdns_is_clock_stop(struct sdw_cdns *cdns);
int sdw_cdns_clock_stop(struct sdw_cdns *cdns, bool block_wake);
int sdw_cdns_clock_restart(struct sdw_cdns *cdns, bool bus_reset);
#ifdef CONFIG_DEBUG_FS
void sdw_cdns_debugfs_init(struct sdw_cdns *cdns, struct dentry *root);
#endif
struct sdw_cdns_pdi *sdw_cdns_alloc_pdi(struct sdw_cdns *cdns,
struct sdw_cdns_streams *stream,
u32 ch, u32 dir, int dai_id);
void sdw_cdns_config_stream(struct sdw_cdns *cdns,
u32 ch, u32 dir, struct sdw_cdns_pdi *pdi);
enum sdw_command_response
cdns_reset_page_addr(struct sdw_bus *bus, unsigned int dev_num);
enum sdw_command_response
cdns_xfer_msg(struct sdw_bus *bus, struct sdw_msg *msg);
enum sdw_command_response
cdns_xfer_msg_defer(struct sdw_bus *bus,
struct sdw_msg *msg, struct sdw_defer *defer);
int cdns_bus_conf(struct sdw_bus *bus, struct sdw_bus_params *params);
int cdns_set_sdw_stream(struct snd_soc_dai *dai,
void *stream, bool pcm, int direction);
void sdw_cdns_check_self_clearing_bits(struct sdw_cdns *cdns, const char *string,
bool initial_delay, int reset_iterations);
#endif /* __SDW_CADENCE_H */