/* * amdtp-tascam.c - a part of driver for TASCAM FireWire series * * Copyright (c) 2015 Takashi Sakamoto * * Licensed under the terms of the GNU General Public License, version 2. */ #include #include "tascam.h" #define AMDTP_FMT_TSCM_TX 0x1e #define AMDTP_FMT_TSCM_RX 0x3e struct amdtp_tscm { unsigned int pcm_channels; void (*transfer_samples)(struct amdtp_stream *s, struct snd_pcm_substream *pcm, __be32 *buffer, unsigned int frames); }; int amdtp_tscm_set_parameters(struct amdtp_stream *s, unsigned int rate) { struct amdtp_tscm *p = s->protocol; unsigned int data_channels; if (amdtp_stream_running(s)) return -EBUSY; data_channels = p->pcm_channels; /* Packets in in-stream have extra 2 data channels. */ if (s->direction == AMDTP_IN_STREAM) data_channels += 2; return amdtp_stream_set_parameters(s, rate, data_channels); } static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm, __be32 *buffer, unsigned int frames) { struct amdtp_tscm *p = s->protocol; struct snd_pcm_runtime *runtime = pcm->runtime; unsigned int channels, remaining_frames, i, c; const u32 *src; channels = p->pcm_channels; src = (void *)runtime->dma_area + frames_to_bytes(runtime, s->pcm_buffer_pointer); remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer; for (i = 0; i < frames; ++i) { for (c = 0; c < channels; ++c) { buffer[c] = cpu_to_be32(*src); src++; } buffer += s->data_block_quadlets; if (--remaining_frames == 0) src = (void *)runtime->dma_area; } } static void write_pcm_s16(struct amdtp_stream *s, struct snd_pcm_substream *pcm, __be32 *buffer, unsigned int frames) { struct amdtp_tscm *p = s->protocol; struct snd_pcm_runtime *runtime = pcm->runtime; unsigned int channels, remaining_frames, i, c; const u16 *src; channels = p->pcm_channels; src = (void *)runtime->dma_area + frames_to_bytes(runtime, s->pcm_buffer_pointer); remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer; for (i = 0; i < frames; ++i) { for (c = 0; c < channels; ++c) { buffer[c] = cpu_to_be32(*src << 16); src++; } buffer += s->data_block_quadlets; if (--remaining_frames == 0) src = (void *)runtime->dma_area; } } static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm, __be32 *buffer, unsigned int frames) { struct amdtp_tscm *p = s->protocol; struct snd_pcm_runtime *runtime = pcm->runtime; unsigned int channels, remaining_frames, i, c; u32 *dst; channels = p->pcm_channels; dst = (void *)runtime->dma_area + frames_to_bytes(runtime, s->pcm_buffer_pointer); remaining_frames = runtime->buffer_size - s->pcm_buffer_pointer; /* The first data channel is for event counter. */ buffer += 1; for (i = 0; i < frames; ++i) { for (c = 0; c < channels; ++c) { *dst = be32_to_cpu(buffer[c]); dst++; } buffer += s->data_block_quadlets; if (--remaining_frames == 0) dst = (void *)runtime->dma_area; } } static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer, unsigned int data_blocks) { struct amdtp_tscm *p = s->protocol; unsigned int channels, i, c; channels = p->pcm_channels; for (i = 0; i < data_blocks; ++i) { for (c = 0; c < channels; ++c) buffer[c] = 0x00000000; buffer += s->data_block_quadlets; } } int amdtp_tscm_add_pcm_hw_constraints(struct amdtp_stream *s, struct snd_pcm_runtime *runtime) { int err; /* * Our implementation allows this protocol to deliver 24 bit sample in * 32bit data channel. */ err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24); if (err < 0) return err; return amdtp_stream_add_pcm_hw_constraints(s, runtime); } void amdtp_tscm_set_pcm_format(struct amdtp_stream *s, snd_pcm_format_t format) { struct amdtp_tscm *p = s->protocol; if (WARN_ON(amdtp_stream_pcm_running(s))) return; switch (format) { default: WARN_ON(1); /* fall through */ case SNDRV_PCM_FORMAT_S16: if (s->direction == AMDTP_OUT_STREAM) { p->transfer_samples = write_pcm_s16; break; } WARN_ON(1); /* fall through */ case SNDRV_PCM_FORMAT_S32: if (s->direction == AMDTP_OUT_STREAM) p->transfer_samples = write_pcm_s32; else p->transfer_samples = read_pcm_s32; break; } } static unsigned int process_tx_data_blocks(struct amdtp_stream *s, __be32 *buffer, unsigned int data_blocks, unsigned int *syt) { struct amdtp_tscm *p = (struct amdtp_tscm *)s->protocol; struct snd_pcm_substream *pcm; pcm = ACCESS_ONCE(s->pcm); if (data_blocks > 0 && pcm) p->transfer_samples(s, pcm, buffer, data_blocks); /* A place holder for control messages. */ return data_blocks; } static unsigned int process_rx_data_blocks(struct amdtp_stream *s, __be32 *buffer, unsigned int data_blocks, unsigned int *syt) { struct amdtp_tscm *p = (struct amdtp_tscm *)s->protocol; struct snd_pcm_substream *pcm; /* This field is not used. */ *syt = 0x0000; pcm = ACCESS_ONCE(s->pcm); if (pcm) p->transfer_samples(s, pcm, buffer, data_blocks); else write_pcm_silence(s, buffer, data_blocks); return data_blocks; } int amdtp_tscm_init(struct amdtp_stream *s, struct fw_unit *unit, enum amdtp_stream_direction dir, unsigned int pcm_channels) { amdtp_stream_process_data_blocks_t process_data_blocks; struct amdtp_tscm *p; unsigned int fmt; int err; if (dir == AMDTP_IN_STREAM) { fmt = AMDTP_FMT_TSCM_TX; process_data_blocks = process_tx_data_blocks; } else { fmt = AMDTP_FMT_TSCM_RX; process_data_blocks = process_rx_data_blocks; } err = amdtp_stream_init(s, unit, dir, CIP_NONBLOCKING | CIP_SKIP_DBC_ZERO_CHECK, fmt, process_data_blocks, sizeof(struct amdtp_tscm)); if (err < 0) return 0; /* Use fixed value for FDF field. */ s->fdf = 0x00; /* This protocol uses fixed number of data channels for PCM samples. */ p = s->protocol; p->pcm_channels = pcm_channels; return 0; } 26199 (diff)
dmaengine: pl330: fix double lock
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'include/dt-bindings/clock/hi3620-clock.h')