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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /sound/core/pcm_dmaengine.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to '')
-rw-r--r--sound/core/pcm_dmaengine.c473
1 files changed, 473 insertions, 0 deletions
diff --git a/sound/core/pcm_dmaengine.c b/sound/core/pcm_dmaengine.c
new file mode 100644
index 000000000..494ec0c20
--- /dev/null
+++ b/sound/core/pcm_dmaengine.c
@@ -0,0 +1,473 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2012, Analog Devices Inc.
+ * Author: Lars-Peter Clausen <lars@metafoo.de>
+ *
+ * Based on:
+ * imx-pcm-dma-mx2.c, Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
+ * mxs-pcm.c, Copyright (C) 2011 Freescale Semiconductor, Inc.
+ * ep93xx-pcm.c, Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ * Copyright (C) 2006 Applied Data Systems
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/dmaengine.h>
+#include <linux/slab.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+
+#include <sound/dmaengine_pcm.h>
+
+struct dmaengine_pcm_runtime_data {
+ struct dma_chan *dma_chan;
+ dma_cookie_t cookie;
+
+ unsigned int pos;
+};
+
+static inline struct dmaengine_pcm_runtime_data *substream_to_prtd(
+ const struct snd_pcm_substream *substream)
+{
+ return substream->runtime->private_data;
+}
+
+struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+
+ return prtd->dma_chan;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_get_chan);
+
+/**
+ * snd_hwparams_to_dma_slave_config - Convert hw_params to dma_slave_config
+ * @substream: PCM substream
+ * @params: hw_params
+ * @slave_config: DMA slave config
+ *
+ * This function can be used to initialize a dma_slave_config from a substream
+ * and hw_params in a dmaengine based PCM driver implementation.
+ *
+ * Return: zero if successful, or a negative error code
+ */
+int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
+ const struct snd_pcm_hw_params *params,
+ struct dma_slave_config *slave_config)
+{
+ enum dma_slave_buswidth buswidth;
+ int bits;
+
+ bits = params_physical_width(params);
+ if (bits < 8 || bits > 64)
+ return -EINVAL;
+ else if (bits == 8)
+ buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ else if (bits == 16)
+ buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ else if (bits == 24)
+ buswidth = DMA_SLAVE_BUSWIDTH_3_BYTES;
+ else if (bits <= 32)
+ buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ else
+ buswidth = DMA_SLAVE_BUSWIDTH_8_BYTES;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ slave_config->direction = DMA_MEM_TO_DEV;
+ slave_config->dst_addr_width = buswidth;
+ } else {
+ slave_config->direction = DMA_DEV_TO_MEM;
+ slave_config->src_addr_width = buswidth;
+ }
+
+ slave_config->device_fc = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_hwparams_to_dma_slave_config);
+
+/**
+ * snd_dmaengine_pcm_set_config_from_dai_data() - Initializes a dma slave config
+ * using DAI DMA data.
+ * @substream: PCM substream
+ * @dma_data: DAI DMA data
+ * @slave_config: DMA slave configuration
+ *
+ * Initializes the {dst,src}_addr, {dst,src}_maxburst, {dst,src}_addr_width
+ * fields of the DMA slave config from the same fields of the DAI DMA
+ * data struct. The src and dst fields will be initialized depending on the
+ * direction of the substream. If the substream is a playback stream the dst
+ * fields will be initialized, if it is a capture stream the src fields will be
+ * initialized. The {dst,src}_addr_width field will only be initialized if the
+ * SND_DMAENGINE_PCM_DAI_FLAG_PACK flag is set or if the addr_width field of
+ * the DAI DMA data struct is not equal to DMA_SLAVE_BUSWIDTH_UNDEFINED. If
+ * both conditions are met the latter takes priority.
+ */
+void snd_dmaengine_pcm_set_config_from_dai_data(
+ const struct snd_pcm_substream *substream,
+ const struct snd_dmaengine_dai_dma_data *dma_data,
+ struct dma_slave_config *slave_config)
+{
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+ slave_config->dst_addr = dma_data->addr;
+ slave_config->dst_maxburst = dma_data->maxburst;
+ if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
+ slave_config->dst_addr_width =
+ DMA_SLAVE_BUSWIDTH_UNDEFINED;
+ if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
+ slave_config->dst_addr_width = dma_data->addr_width;
+ } else {
+ slave_config->src_addr = dma_data->addr;
+ slave_config->src_maxburst = dma_data->maxburst;
+ if (dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK)
+ slave_config->src_addr_width =
+ DMA_SLAVE_BUSWIDTH_UNDEFINED;
+ if (dma_data->addr_width != DMA_SLAVE_BUSWIDTH_UNDEFINED)
+ slave_config->src_addr_width = dma_data->addr_width;
+ }
+
+ slave_config->peripheral_config = dma_data->peripheral_config;
+ slave_config->peripheral_size = dma_data->peripheral_size;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_set_config_from_dai_data);
+
+static void dmaengine_pcm_dma_complete(void *arg)
+{
+ unsigned int new_pos;
+ struct snd_pcm_substream *substream = arg;
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+
+ new_pos = prtd->pos + snd_pcm_lib_period_bytes(substream);
+ if (new_pos >= snd_pcm_lib_buffer_bytes(substream))
+ new_pos = 0;
+ prtd->pos = new_pos;
+
+ snd_pcm_period_elapsed(substream);
+}
+
+static int dmaengine_pcm_prepare_and_submit(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ struct dma_chan *chan = prtd->dma_chan;
+ struct dma_async_tx_descriptor *desc;
+ enum dma_transfer_direction direction;
+ unsigned long flags = DMA_CTRL_ACK;
+
+ direction = snd_pcm_substream_to_dma_direction(substream);
+
+ if (!substream->runtime->no_period_wakeup)
+ flags |= DMA_PREP_INTERRUPT;
+
+ prtd->pos = 0;
+ desc = dmaengine_prep_dma_cyclic(chan,
+ substream->runtime->dma_addr,
+ snd_pcm_lib_buffer_bytes(substream),
+ snd_pcm_lib_period_bytes(substream), direction, flags);
+
+ if (!desc)
+ return -ENOMEM;
+
+ desc->callback = dmaengine_pcm_dma_complete;
+ desc->callback_param = substream;
+ prtd->cookie = dmaengine_submit(desc);
+
+ return 0;
+}
+
+/**
+ * snd_dmaengine_pcm_trigger - dmaengine based PCM trigger implementation
+ * @substream: PCM substream
+ * @cmd: Trigger command
+ *
+ * This function can be used as the PCM trigger callback for dmaengine based PCM
+ * driver implementations.
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ int ret;
+
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ ret = dmaengine_pcm_prepare_and_submit(substream);
+ if (ret)
+ return ret;
+ dma_async_issue_pending(prtd->dma_chan);
+ break;
+ case SNDRV_PCM_TRIGGER_RESUME:
+ case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+ dmaengine_resume(prtd->dma_chan);
+ break;
+ case SNDRV_PCM_TRIGGER_SUSPEND:
+ if (runtime->info & SNDRV_PCM_INFO_PAUSE)
+ dmaengine_pause(prtd->dma_chan);
+ else
+ dmaengine_terminate_async(prtd->dma_chan);
+ break;
+ case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+ dmaengine_pause(prtd->dma_chan);
+ break;
+ case SNDRV_PCM_TRIGGER_STOP:
+ dmaengine_terminate_async(prtd->dma_chan);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_trigger);
+
+/**
+ * snd_dmaengine_pcm_pointer_no_residue - dmaengine based PCM pointer implementation
+ * @substream: PCM substream
+ *
+ * This function is deprecated and should not be used by new drivers, as its
+ * results may be unreliable.
+ *
+ * Return: PCM position in frames
+ */
+snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ return bytes_to_frames(substream->runtime, prtd->pos);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer_no_residue);
+
+/**
+ * snd_dmaengine_pcm_pointer - dmaengine based PCM pointer implementation
+ * @substream: PCM substream
+ *
+ * This function can be used as the PCM pointer callback for dmaengine based PCM
+ * driver implementations.
+ *
+ * Return: PCM position in frames
+ */
+snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+ struct snd_pcm_runtime *runtime = substream->runtime;
+ struct dma_tx_state state;
+ enum dma_status status;
+ unsigned int buf_size;
+ unsigned int pos = 0;
+
+ status = dmaengine_tx_status(prtd->dma_chan, prtd->cookie, &state);
+ if (status == DMA_IN_PROGRESS || status == DMA_PAUSED) {
+ buf_size = snd_pcm_lib_buffer_bytes(substream);
+ if (state.residue > 0 && state.residue <= buf_size)
+ pos = buf_size - state.residue;
+
+ runtime->delay = bytes_to_frames(runtime,
+ state.in_flight_bytes);
+ }
+
+ return bytes_to_frames(runtime, pos);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_pointer);
+
+/**
+ * snd_dmaengine_pcm_request_channel - Request channel for the dmaengine PCM
+ * @filter_fn: Filter function used to request the DMA channel
+ * @filter_data: Data passed to the DMA filter function
+ *
+ * This function request a DMA channel for usage with dmaengine PCM.
+ *
+ * Return: NULL or the requested DMA channel
+ */
+struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
+ void *filter_data)
+{
+ dma_cap_mask_t mask;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ dma_cap_set(DMA_CYCLIC, mask);
+
+ return dma_request_channel(mask, filter_fn, filter_data);
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_request_channel);
+
+/**
+ * snd_dmaengine_pcm_open - Open a dmaengine based PCM substream
+ * @substream: PCM substream
+ * @chan: DMA channel to use for data transfers
+ *
+ * The function should usually be called from the pcm open callback. Note that
+ * this function will use private_data field of the substream's runtime. So it
+ * is not available to your pcm driver implementation.
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,
+ struct dma_chan *chan)
+{
+ struct dmaengine_pcm_runtime_data *prtd;
+ int ret;
+
+ if (!chan)
+ return -ENXIO;
+
+ ret = snd_pcm_hw_constraint_integer(substream->runtime,
+ SNDRV_PCM_HW_PARAM_PERIODS);
+ if (ret < 0)
+ return ret;
+
+ prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
+ if (!prtd)
+ return -ENOMEM;
+
+ prtd->dma_chan = chan;
+
+ substream->runtime->private_data = prtd;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open);
+
+/**
+ * snd_dmaengine_pcm_open_request_chan - Open a dmaengine based PCM substream and request channel
+ * @substream: PCM substream
+ * @filter_fn: Filter function used to request the DMA channel
+ * @filter_data: Data passed to the DMA filter function
+ *
+ * This function will request a DMA channel using the passed filter function and
+ * data. The function should usually be called from the pcm open callback. Note
+ * that this function will use private_data field of the substream's runtime. So
+ * it is not available to your pcm driver implementation.
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
+ dma_filter_fn filter_fn, void *filter_data)
+{
+ return snd_dmaengine_pcm_open(substream,
+ snd_dmaengine_pcm_request_channel(filter_fn, filter_data));
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_open_request_chan);
+
+/**
+ * snd_dmaengine_pcm_close - Close a dmaengine based PCM substream
+ * @substream: PCM substream
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+
+ dmaengine_synchronize(prtd->dma_chan);
+ kfree(prtd);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close);
+
+/**
+ * snd_dmaengine_pcm_close_release_chan - Close a dmaengine based PCM
+ * substream and release channel
+ * @substream: PCM substream
+ *
+ * Releases the DMA channel associated with the PCM substream.
+ *
+ * Return: zero if successful, or a negative error code
+ */
+int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream)
+{
+ struct dmaengine_pcm_runtime_data *prtd = substream_to_prtd(substream);
+
+ dmaengine_synchronize(prtd->dma_chan);
+ dma_release_channel(prtd->dma_chan);
+ kfree(prtd);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_close_release_chan);
+
+/**
+ * snd_dmaengine_pcm_refine_runtime_hwparams - Refine runtime hw params
+ * @substream: PCM substream
+ * @dma_data: DAI DMA data
+ * @hw: PCM hw params
+ * @chan: DMA channel to use for data transfers
+ *
+ * This function will query DMA capability, then refine the pcm hardware
+ * parameters.
+ *
+ * Return: 0 on success, a negative error code otherwise
+ */
+int snd_dmaengine_pcm_refine_runtime_hwparams(
+ struct snd_pcm_substream *substream,
+ struct snd_dmaengine_dai_dma_data *dma_data,
+ struct snd_pcm_hardware *hw,
+ struct dma_chan *chan)
+{
+ struct dma_slave_caps dma_caps;
+ u32 addr_widths = BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) |
+ BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) |
+ BIT(DMA_SLAVE_BUSWIDTH_4_BYTES);
+ snd_pcm_format_t i;
+ int ret = 0;
+
+ if (!hw || !chan || !dma_data)
+ return -EINVAL;
+
+ ret = dma_get_slave_caps(chan, &dma_caps);
+ if (ret == 0) {
+ if (dma_caps.cmd_pause && dma_caps.cmd_resume)
+ hw->info |= SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME;
+ if (dma_caps.residue_granularity <= DMA_RESIDUE_GRANULARITY_SEGMENT)
+ hw->info |= SNDRV_PCM_INFO_BATCH;
+
+ if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+ addr_widths = dma_caps.dst_addr_widths;
+ else
+ addr_widths = dma_caps.src_addr_widths;
+ }
+
+ /*
+ * If SND_DMAENGINE_PCM_DAI_FLAG_PACK is set keep
+ * hw.formats set to 0, meaning no restrictions are in place.
+ * In this case it's the responsibility of the DAI driver to
+ * provide the supported format information.
+ */
+ if (!(dma_data->flags & SND_DMAENGINE_PCM_DAI_FLAG_PACK))
+ /*
+ * Prepare formats mask for valid/allowed sample types. If the
+ * dma does not have support for the given physical word size,
+ * it needs to be masked out so user space can not use the
+ * format which produces corrupted audio.
+ * In case the dma driver does not implement the slave_caps the
+ * default assumption is that it supports 1, 2 and 4 bytes
+ * widths.
+ */
+ pcm_for_each_format(i) {
+ int bits = snd_pcm_format_physical_width(i);
+
+ /*
+ * Enable only samples with DMA supported physical
+ * widths
+ */
+ switch (bits) {
+ case 8:
+ case 16:
+ case 24:
+ case 32:
+ case 64:
+ if (addr_widths & (1 << (bits / 8)))
+ hw->formats |= pcm_format_to_bits(i);
+ break;
+ default:
+ /* Unsupported types */
+ break;
+ }
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(snd_dmaengine_pcm_refine_runtime_hwparams);
+
+MODULE_LICENSE("GPL");