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-rw-r--r--Documentation/ABI/stable/sysfs-bus-usb8
-rw-r--r--Documentation/ABI/testing/sysfs-devices-power32
-rw-r--r--Documentation/ABI/testing/sysfs-power22
-rw-r--r--Documentation/acpi/dsdt-override.txt2
-rw-r--r--Documentation/connector/ucon.c2
-rw-r--r--Documentation/devicetree/bindings/memory.txt168
-rw-r--r--Documentation/devicetree/bindings/sound/cs42l73.txt22
-rw-r--r--Documentation/devicetree/bindings/sound/davinci-evm-audio.txt42
-rw-r--r--Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt41
-rw-r--r--Documentation/sound/alsa/soc/DPCM.txt380
-rw-r--r--Documentation/sound/alsa/soc/codec.txt46
-rw-r--r--Documentation/sound/alsa/soc/dapm.txt71
-rw-r--r--Documentation/sound/alsa/soc/machine.txt6
-rw-r--r--Documentation/sound/alsa/soc/platform.txt19
14 files changed, 580 insertions, 281 deletions
diff --git a/Documentation/ABI/stable/sysfs-bus-usb b/Documentation/ABI/stable/sysfs-bus-usb
index 2be603c52a24..a6b685724740 100644
--- a/Documentation/ABI/stable/sysfs-bus-usb
+++ b/Documentation/ABI/stable/sysfs-bus-usb
@@ -37,8 +37,8 @@ Description:
that the USB device has been connected to the machine. This
file is read-only.
Users:
- PowerTOP <power@bughost.org>
- http://www.lesswatts.org/projects/powertop/
+ PowerTOP <powertop@lists.01.org>
+ https://01.org/powertop/
What: /sys/bus/usb/device/.../power/active_duration
Date: January 2008
@@ -57,8 +57,8 @@ Description:
will give an integer percentage. Note that this does not
account for counter wrap.
Users:
- PowerTOP <power@bughost.org>
- http://www.lesswatts.org/projects/powertop/
+ PowerTOP <powertop@lists.01.org>
+ https://01.org/powertop/
What: /sys/bus/usb/devices/<busnum>-<port[.port]>...:<config num>-<interface num>/supports_autosuspend
Date: January 2008
diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power
index 9d43e7670841..efe449bdf811 100644
--- a/Documentation/ABI/testing/sysfs-devices-power
+++ b/Documentation/ABI/testing/sysfs-devices-power
@@ -1,6 +1,6 @@
What: /sys/devices/.../power/
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power directory contains attributes
allowing the user space to check and modify some power
@@ -8,7 +8,7 @@ Description:
What: /sys/devices/.../power/wakeup
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power/wakeup attribute allows the user
space to check if the device is enabled to wake up the system
@@ -34,7 +34,7 @@ Description:
What: /sys/devices/.../power/control
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power/control attribute allows the user
space to control the run-time power management of the device.
@@ -53,7 +53,7 @@ Description:
What: /sys/devices/.../power/async
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../async attribute allows the user space to
enable or diasble the device's suspend and resume callbacks to
@@ -79,7 +79,7 @@ Description:
What: /sys/devices/.../power/wakeup_count
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_count attribute contains the number
of signaled wakeup events associated with the device. This
@@ -88,7 +88,7 @@ Description:
What: /sys/devices/.../power/wakeup_active_count
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_active_count attribute contains the
number of times the processing of wakeup events associated with
@@ -98,7 +98,7 @@ Description:
What: /sys/devices/.../power/wakeup_abort_count
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_abort_count attribute contains the
number of times the processing of a wakeup event associated with
@@ -109,7 +109,7 @@ Description:
What: /sys/devices/.../power/wakeup_expire_count
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_expire_count attribute contains the
number of times a wakeup event associated with the device has
@@ -119,7 +119,7 @@ Description:
What: /sys/devices/.../power/wakeup_active
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_active attribute contains either 1,
or 0, depending on whether or not a wakeup event associated with
@@ -129,7 +129,7 @@ Description:
What: /sys/devices/.../power/wakeup_total_time_ms
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_total_time_ms attribute contains
the total time of processing wakeup events associated with the
@@ -139,7 +139,7 @@ Description:
What: /sys/devices/.../power/wakeup_max_time_ms
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_max_time_ms attribute contains
the maximum time of processing a single wakeup event associated
@@ -149,7 +149,7 @@ Description:
What: /sys/devices/.../power/wakeup_last_time_ms
Date: September 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_last_time_ms attribute contains
the value of the monotonic clock corresponding to the time of
@@ -160,7 +160,7 @@ Description:
What: /sys/devices/.../power/wakeup_prevent_sleep_time_ms
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../wakeup_prevent_sleep_time_ms attribute
contains the total time the device has been preventing
@@ -189,7 +189,7 @@ Description:
What: /sys/devices/.../power/pm_qos_latency_us
Date: March 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power/pm_qos_resume_latency_us attribute
contains the PM QoS resume latency limit for the given device,
@@ -207,7 +207,7 @@ Description:
What: /sys/devices/.../power/pm_qos_no_power_off
Date: September 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power/pm_qos_no_power_off attribute
is used for manipulating the PM QoS "no power off" flag. If
@@ -222,7 +222,7 @@ Description:
What: /sys/devices/.../power/pm_qos_remote_wakeup
Date: September 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/devices/.../power/pm_qos_remote_wakeup attribute
is used for manipulating the PM QoS "remote wakeup required"
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power
index 217772615d02..205a73878441 100644
--- a/Documentation/ABI/testing/sysfs-power
+++ b/Documentation/ABI/testing/sysfs-power
@@ -1,6 +1,6 @@
What: /sys/power/
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power directory will contain files that will
provide a unified interface to the power management
@@ -8,7 +8,7 @@ Description:
What: /sys/power/state
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/state file controls the system power state.
Reading from this file returns what states are supported,
@@ -22,7 +22,7 @@ Description:
What: /sys/power/disk
Date: September 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/disk file controls the operating mode of the
suspend-to-disk mechanism. Reading from this file returns
@@ -67,7 +67,7 @@ Description:
What: /sys/power/image_size
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/image_size file controls the size of the image
created by the suspend-to-disk mechanism. It can be written a
@@ -84,7 +84,7 @@ Description:
What: /sys/power/pm_trace
Date: August 2006
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/pm_trace file controls the code which saves the
last PM event point in the RTC across reboots, so that you can
@@ -133,7 +133,7 @@ Description:
What: /sys/power/pm_async
Date: January 2009
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/pm_async file controls the switch allowing the
user space to enable or disable asynchronous suspend and resume
@@ -146,7 +146,7 @@ Description:
What: /sys/power/wakeup_count
Date: July 2010
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wakeup_count file allows user space to put the
system into a sleep state while taking into account the
@@ -161,7 +161,7 @@ Description:
What: /sys/power/reserved_size
Date: May 2011
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/reserved_size file allows user space to control
the amount of memory reserved for allocations made by device
@@ -175,7 +175,7 @@ Description:
What: /sys/power/autosleep
Date: April 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/autosleep file can be written one of the strings
returned by reads from /sys/power/state. If that happens, a
@@ -192,7 +192,7 @@ Description:
What: /sys/power/wake_lock
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wake_lock file allows user space to create
wakeup source objects and activate them on demand (if one of
@@ -219,7 +219,7 @@ Description:
What: /sys/power/wake_unlock
Date: February 2012
-Contact: Rafael J. Wysocki <rjw@sisk.pl>
+Contact: Rafael J. Wysocki <rjw@rjwysocki.net>
Description:
The /sys/power/wake_unlock file allows user space to deactivate
wakeup sources created with the help of /sys/power/wake_lock.
diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/acpi/dsdt-override.txt
index febbb1ba4d23..784841caa6e6 100644
--- a/Documentation/acpi/dsdt-override.txt
+++ b/Documentation/acpi/dsdt-override.txt
@@ -4,4 +4,4 @@ CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel.
When to use this method is described in detail on the
Linux/ACPI home page:
-http://www.lesswatts.org/projects/acpi/overridingDSDT.php
+https://01.org/linux-acpi/documentation/overriding-dsdt
diff --git a/Documentation/connector/ucon.c b/Documentation/connector/ucon.c
index 4848db8c71ff..8a4da64e02a8 100644
--- a/Documentation/connector/ucon.c
+++ b/Documentation/connector/ucon.c
@@ -71,7 +71,7 @@ static int netlink_send(int s, struct cn_msg *msg)
nlh->nlmsg_seq = seq++;
nlh->nlmsg_pid = getpid();
nlh->nlmsg_type = NLMSG_DONE;
- nlh->nlmsg_len = NLMSG_LENGTH(size - sizeof(*nlh));
+ nlh->nlmsg_len = size;
nlh->nlmsg_flags = 0;
m = NLMSG_DATA(nlh);
diff --git a/Documentation/devicetree/bindings/memory.txt b/Documentation/devicetree/bindings/memory.txt
deleted file mode 100644
index eb2469365593..000000000000
--- a/Documentation/devicetree/bindings/memory.txt
+++ /dev/null
@@ -1,168 +0,0 @@
-*** Memory binding ***
-
-The /memory node provides basic information about the address and size
-of the physical memory. This node is usually filled or updated by the
-bootloader, depending on the actual memory configuration of the given
-hardware.
-
-The memory layout is described by the following node:
-
-/ {
- #address-cells = <(n)>;
- #size-cells = <(m)>;
- memory {
- device_type = "memory";
- reg = <(baseaddr1) (size1)
- (baseaddr2) (size2)
- ...
- (baseaddrN) (sizeN)>;
- };
- ...
-};
-
-A memory node follows the typical device tree rules for "reg" property:
-n: number of cells used to store base address value
-m: number of cells used to store size value
-baseaddrX: defines a base address of the defined memory bank
-sizeX: the size of the defined memory bank
-
-
-More than one memory bank can be defined.
-
-
-*** Reserved memory regions ***
-
-In /memory/reserved-memory node one can create child nodes describing
-particular reserved (excluded from normal use) memory regions. Such
-memory regions are usually designed for the special usage by various
-device drivers. A good example are contiguous memory allocations or
-memory sharing with other operating system on the same hardware board.
-Those special memory regions might depend on the board configuration and
-devices used on the target system.
-
-Parameters for each memory region can be encoded into the device tree
-with the following convention:
-
-[(label):] (name) {
- compatible = "linux,contiguous-memory-region", "reserved-memory-region";
- reg = <(address) (size)>;
- (linux,default-contiguous-region);
-};
-
-compatible: one or more of:
- - "linux,contiguous-memory-region" - enables binding of this
- region to Contiguous Memory Allocator (special region for
- contiguous memory allocations, shared with movable system
- memory, Linux kernel-specific).
- - "reserved-memory-region" - compatibility is defined, given
- region is assigned for exclusive usage for by the respective
- devices.
-
-reg: standard property defining the base address and size of
- the memory region
-
-linux,default-contiguous-region: property indicating that the region
- is the default region for all contiguous memory
- allocations, Linux specific (optional)
-
-It is optional to specify the base address, so if one wants to use
-autoconfiguration of the base address, '0' can be specified as a base
-address in the 'reg' property.
-
-The /memory/reserved-memory node must contain the same #address-cells
-and #size-cells value as the root node.
-
-
-*** Device node's properties ***
-
-Once regions in the /memory/reserved-memory node have been defined, they
-may be referenced by other device nodes. Bindings that wish to reference
-memory regions should explicitly document their use of the following
-property:
-
-memory-region = <&phandle_to_defined_region>;
-
-This property indicates that the device driver should use the memory
-region pointed by the given phandle.
-
-
-*** Example ***
-
-This example defines a memory consisting of 4 memory banks. 3 contiguous
-regions are defined for Linux kernel, one default of all device drivers
-(named contig_mem, placed at 0x72000000, 64MiB), one dedicated to the
-framebuffer device (labelled display_mem, placed at 0x78000000, 8MiB)
-and one for multimedia processing (labelled multimedia_mem, placed at
-0x77000000, 64MiB). 'display_mem' region is then assigned to fb@12300000
-device for DMA memory allocations (Linux kernel drivers will use CMA is
-available or dma-exclusive usage otherwise). 'multimedia_mem' is
-assigned to scaler@12500000 and codec@12600000 devices for contiguous
-memory allocations when CMA driver is enabled.
-
-The reason for creating a separate region for framebuffer device is to
-match the framebuffer base address to the one configured by bootloader,
-so once Linux kernel drivers starts no glitches on the displayed boot
-logo appears. Scaller and codec drivers should share the memory
-allocations.
-
-/ {
- #address-cells = <1>;
- #size-cells = <1>;
-
- /* ... */
-
- memory {
- reg = <0x40000000 0x10000000
- 0x50000000 0x10000000
- 0x60000000 0x10000000
- 0x70000000 0x10000000>;
-
- reserved-memory {
- #address-cells = <1>;
- #size-cells = <1>;
-
- /*
- * global autoconfigured region for contiguous allocations
- * (used only with Contiguous Memory Allocator)
- */
- contig_region@0 {
- compatible = "linux,contiguous-memory-region";
- reg = <0x0 0x4000000>;
- linux,default-contiguous-region;
- };
-
- /*
- * special region for framebuffer
- */
- display_region: region@78000000 {
- compatible = "linux,contiguous-memory-region", "reserved-memory-region";
- reg = <0x78000000 0x800000>;
- };
-
- /*
- * special region for multimedia processing devices
- */
- multimedia_region: region@77000000 {
- compatible = "linux,contiguous-memory-region";
- reg = <0x77000000 0x4000000>;
- };
- };
- };
-
- /* ... */
-
- fb0: fb@12300000 {
- status = "okay";
- memory-region = <&display_region>;
- };
-
- scaler: scaler@12500000 {
- status = "okay";
- memory-region = <&multimedia_region>;
- };
-
- codec: codec@12600000 {
- status = "okay";
- memory-region = <&multimedia_region>;
- };
-};
diff --git a/Documentation/devicetree/bindings/sound/cs42l73.txt b/Documentation/devicetree/bindings/sound/cs42l73.txt
new file mode 100644
index 000000000000..80ae910dbf6c
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/cs42l73.txt
@@ -0,0 +1,22 @@
+CS42L73 audio CODEC
+
+Required properties:
+
+ - compatible : "cirrus,cs42l73"
+
+ - reg : the I2C address of the device for I2C
+
+Optional properties:
+
+ - reset_gpio : a GPIO spec for the reset pin.
+ - chgfreq : Charge Pump Frequency values 0x00-0x0F
+
+
+Example:
+
+codec: cs42l73@4a {
+ compatible = "cirrus,cs42l73";
+ reg = <0x4a>;
+ reset_gpio = <&gpio 10 0>;
+ chgfreq = <0x05>;
+}; \ No newline at end of file
diff --git a/Documentation/devicetree/bindings/sound/davinci-evm-audio.txt b/Documentation/devicetree/bindings/sound/davinci-evm-audio.txt
new file mode 100644
index 000000000000..865178d5cdf3
--- /dev/null
+++ b/Documentation/devicetree/bindings/sound/davinci-evm-audio.txt
@@ -0,0 +1,42 @@
+* Texas Instruments SoC audio setups with TLV320AIC3X Codec
+
+Required properties:
+- compatible : "ti,da830-evm-audio" : forDM365/DA8xx/OMAPL1x/AM33xx
+- ti,model : The user-visible name of this sound complex.
+- ti,audio-codec : The phandle of the TLV320AIC3x audio codec
+- ti,mcasp-controller : The phandle of the McASP controller
+- ti,codec-clock-rate : The Codec Clock rate (in Hz) applied to the Codec
+- ti,audio-routing : A list of the connections between audio components.
+ Each entry is a pair of strings, the first being the connection's sink,
+ the second being the connection's source. Valid names for sources and
+ sinks are the codec's pins, and the jacks on the board:
+
+ Board connectors:
+
+ * Headphone Jack
+ * Line Out
+ * Mic Jack
+ * Line In
+
+
+Example:
+
+sound {
+ compatible = "ti,da830-evm-audio";
+ ti,model = "DA830 EVM";
+ ti,audio-codec = <&tlv320aic3x>;
+ ti,mcasp-controller = <&mcasp1>;
+ ti,codec-clock-rate = <12000000>;
+ ti,audio-routing =
+ "Headphone Jack", "HPLOUT",
+ "Headphone Jack", "HPROUT",
+ "Line Out", "LLOUT",
+ "Line Out", "RLOUT",
+ "MIC3L", "Mic Bias 2V",
+ "MIC3R", "Mic Bias 2V",
+ "Mic Bias 2V", "Mic Jack",
+ "LINE1L", "Line In",
+ "LINE2L", "Line In",
+ "LINE1R", "Line In",
+ "LINE2R", "Line In";
+};
diff --git a/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt b/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt
index 374e145c2ef1..ed785b3f67be 100644
--- a/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt
+++ b/Documentation/devicetree/bindings/sound/davinci-mcasp-audio.txt
@@ -4,17 +4,25 @@ Required properties:
- compatible :
"ti,dm646x-mcasp-audio" : for DM646x platforms
"ti,da830-mcasp-audio" : for both DA830 & DA850 platforms
- "ti,omap2-mcasp-audio" : for OMAP2 platforms (TI81xx, AM33xx)
-
-- reg : Should contain McASP registers offset and length
-- interrupts : Interrupt number for McASP
-- op-mode : I2S/DIT ops mode.
-- tdm-slots : Slots for TDM operation.
-- num-serializer : Serializers used by McASP.
-- serial-dir : A list of serializer pin mode. The list number should be equal
- to "num-serializer" parameter. Each entry is a number indication
- serializer pin direction. (0 - INACTIVE, 1 - TX, 2 - RX)
+ "ti,am33xx-mcasp-audio" : for AM33xx platforms (AM33xx, TI81xx)
+- reg : Should contain reg specifiers for the entries in the reg-names property.
+- reg-names : Should contain:
+ * "mpu" for the main registers (required). For compatibility with
+ existing software, it is recommended this is the first entry.
+ * "dat" for separate data port register access (optional).
+- op-mode : I2S/DIT ops mode. 0 for I2S mode. 1 for DIT mode used for S/PDIF,
+ IEC60958-1, and AES-3 formats.
+- tdm-slots : Slots for TDM operation. Indicates number of channels transmitted
+ or received over one serializer.
+- serial-dir : A list of serializer configuration. Each entry is a number
+ indication for serializer pin direction.
+ (0 - INACTIVE, 1 - TX, 2 - RX)
+- dmas: two element list of DMA controller phandles and DMA request line
+ ordered pairs.
+- dma-names: identifier string for each DMA request line in the dmas property.
+ These strings correspond 1:1 with the ordered pairs in dmas. The dma
+ identifiers must be "rx" and "tx".
Optional properties:
@@ -23,18 +31,23 @@ Optional properties:
- rx-num-evt : FIFO levels.
- sram-size-playback : size of sram to be allocated during playback
- sram-size-capture : size of sram to be allocated during capture
+- interrupts : Interrupt numbers for McASP, currently not used by the driver
+- interrupt-names : Known interrupt names are "tx" and "rx"
+- pinctrl-0: Should specify pin control group used for this controller.
+- pinctrl-names: Should contain only one value - "default", for more details
+ please refer to pinctrl-bindings.txt
+
Example:
mcasp0: mcasp0@1d00000 {
compatible = "ti,da830-mcasp-audio";
- #address-cells = <1>;
- #size-cells = <0>;
reg = <0x100000 0x3000>;
- interrupts = <82 83>;
+ reg-names "mpu";
+ interrupts = <82>, <83>;
+ interrupts-names = "tx", "rx";
op-mode = <0>; /* MCASP_IIS_MODE */
tdm-slots = <2>;
- num-serializer = <16>;
serial-dir = <
0 0 0 0 /* 0: INACTIVE, 1: TX, 2: RX */
0 0 0 0
diff --git a/Documentation/sound/alsa/soc/DPCM.txt b/Documentation/sound/alsa/soc/DPCM.txt
new file mode 100644
index 000000000000..aa8546f2d144
--- /dev/null
+++ b/Documentation/sound/alsa/soc/DPCM.txt
@@ -0,0 +1,380 @@
+Dynamic PCM
+===========
+
+1. Description
+==============
+
+Dynamic PCM allows an ALSA PCM device to digitally route its PCM audio to
+various digital endpoints during the PCM stream runtime. e.g. PCM0 can route
+digital audio to I2S DAI0, I2S DAI1 or PDM DAI2. This is useful for on SoC DSP
+drivers that expose several ALSA PCMs and can route to multiple DAIs.
+
+The DPCM runtime routing is determined by the ALSA mixer settings in the same
+way as the analog signal is routed in an ASoC codec driver. DPCM uses a DAPM
+graph representing the DSP internal audio paths and uses the mixer settings to
+determine the patch used by each ALSA PCM.
+
+DPCM re-uses all the existing component codec, platform and DAI drivers without
+any modifications.
+
+
+Phone Audio System with SoC based DSP
+-------------------------------------
+
+Consider the following phone audio subsystem. This will be used in this
+document for all examples :-
+
+| Front End PCMs | SoC DSP | Back End DAIs | Audio devices |
+
+ *************
+PCM0 <------------> * * <----DAI0-----> Codec Headset
+ * *
+PCM1 <------------> * * <----DAI1-----> Codec Speakers
+ * DSP *
+PCM2 <------------> * * <----DAI2-----> MODEM
+ * *
+PCM3 <------------> * * <----DAI3-----> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+This diagram shows a simple smart phone audio subsystem. It supports Bluetooth,
+FM digital radio, Speakers, Headset Jack, digital microphones and cellular
+modem. This sound card exposes 4 DSP front end (FE) ALSA PCM devices and
+supports 6 back end (BE) DAIs. Each FE PCM can digitally route audio data to any
+of the BE DAIs. The FE PCM devices can also route audio to more than 1 BE DAI.
+
+
+
+Example - DPCM Switching playback from DAI0 to DAI1
+---------------------------------------------------
+
+Audio is being played to the Headset. After a while the user removes the headset
+and audio continues playing on the speakers.
+
+Playback on PCM0 to Headset would look like :-
+
+ *************
+PCM0 <============> * * <====DAI0=====> Codec Headset
+ * *
+PCM1 <------------> * * <----DAI1-----> Codec Speakers
+ * DSP *
+PCM2 <------------> * * <----DAI2-----> MODEM
+ * *
+PCM3 <------------> * * <----DAI3-----> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+The headset is removed from the jack by user so the speakers must now be used :-
+
+ *************
+PCM0 <============> * * <----DAI0-----> Codec Headset
+ * *
+PCM1 <------------> * * <====DAI1=====> Codec Speakers
+ * DSP *
+PCM2 <------------> * * <----DAI2-----> MODEM
+ * *
+PCM3 <------------> * * <----DAI3-----> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+The audio driver processes this as follows :-
+
+ 1) Machine driver receives Jack removal event.
+
+ 2) Machine driver OR audio HAL disables the Headset path.
+
+ 3) DPCM runs the PCM trigger(stop), hw_free(), shutdown() operations on DAI0
+ for headset since the path is now disabled.
+
+ 4) Machine driver or audio HAL enables the speaker path.
+
+ 5) DPCM runs the PCM ops for startup(), hw_params(), prepapre() and
+ trigger(start) for DAI1 Speakers since the path is enabled.
+
+In this example, the machine driver or userspace audio HAL can alter the routing
+and then DPCM will take care of managing the DAI PCM operations to either bring
+the link up or down. Audio playback does not stop during this transition.
+
+
+
+DPCM machine driver
+===================
+
+The DPCM enabled ASoC machine driver is similar to normal machine drivers
+except that we also have to :-
+
+ 1) Define the FE and BE DAI links.
+
+ 2) Define any FE/BE PCM operations.
+
+ 3) Define widget graph connections.
+
+
+1 FE and BE DAI links
+---------------------
+
+| Front End PCMs | SoC DSP | Back End DAIs | Audio devices |
+
+ *************
+PCM0 <------------> * * <----DAI0-----> Codec Headset
+ * *
+PCM1 <------------> * * <----DAI1-----> Codec Speakers
+ * DSP *
+PCM2 <------------> * * <----DAI2-----> MODEM
+ * *
+PCM3 <------------> * * <----DAI3-----> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+For the example above we have to define 4 FE DAI links and 6 BE DAI links. The
+FE DAI links are defined as follows :-
+
+static struct snd_soc_dai_link machine_dais[] = {
+ {
+ .name = "PCM0 System",
+ .stream_name = "System Playback",
+ .cpu_dai_name = "System Pin",
+ .platform_name = "dsp-audio",
+ .codec_name = "snd-soc-dummy",
+ .codec_dai_name = "snd-soc-dummy-dai",
+ .dynamic = 1,
+ .trigger = {SND_SOC_DPCM_TRIGGER_POST, SND_SOC_DPCM_TRIGGER_POST},
+ .dpcm_playback = 1,
+ },
+ .....< other FE and BE DAI links here >
+};
+
+This FE DAI link is pretty similar to a regular DAI link except that we also
+set the DAI link to a DPCM FE with the "dynamic = 1". The supported FE stream
+directions should also be set with the "dpcm_playback" and "dpcm_capture"
+flags. There is also an option to specify the ordering of the trigger call for
+each FE. This allows the ASoC core to trigger the DSP before or after the other
+components (as some DSPs have strong requirements for the ordering DAI/DSP
+start and stop sequences).
+
+The FE DAI above sets the codec and code DAIs to dummy devices since the BE is
+dynamic and will change depending on runtime config.
+
+The BE DAIs are configured as follows :-
+
+static struct snd_soc_dai_link machine_dais[] = {
+ .....< FE DAI links here >
+ {
+ .name = "Codec Headset",
+ .cpu_dai_name = "ssp-dai.0",
+ .platform_name = "snd-soc-dummy",
+ .no_pcm = 1,
+ .codec_name = "rt5640.0-001c",
+ .codec_dai_name = "rt5640-aif1",
+ .ignore_suspend = 1,
+ .ignore_pmdown_time = 1,
+ .be_hw_params_fixup = hswult_ssp0_fixup,
+ .ops = &haswell_ops,
+ .dpcm_playback = 1,
+ .dpcm_capture = 1,
+ },
+ .....< other BE DAI links here >
+};
+
+This BE DAI link connects DAI0 to the codec (in this case RT5460 AIF1). It sets
+the "no_pcm" flag to mark it has a BE and sets flags for supported stream
+directions using "dpcm_playback" and "dpcm_capture" above.
+
+The BE has also flags set for ignoreing suspend and PM down time. This allows
+the BE to work in a hostless mode where the host CPU is not transferring data
+like a BT phone call :-
+
+ *************
+PCM0 <------------> * * <----DAI0-----> Codec Headset
+ * *
+PCM1 <------------> * * <----DAI1-----> Codec Speakers
+ * DSP *
+PCM2 <------------> * * <====DAI2=====> MODEM
+ * *
+PCM3 <------------> * * <====DAI3=====> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+This allows the host CPU to sleep whilst the DSP, MODEM DAI and the BT DAI are
+still in operation.
+
+A BE DAI link can also set the codec to a dummy device if the code is a device
+that is managed externally.
+
+Likewise a BE DAI can also set a dummy cpu DAI if the CPU DAI is managed by the
+DSP firmware.
+
+
+2 FE/BE PCM operations
+----------------------
+
+The BE above also exports some PCM operations and a "fixup" callback. The fixup
+callback is used by the machine driver to (re)configure the DAI based upon the
+FE hw params. i.e. the DSP may perform SRC or ASRC from the FE to BE.
+
+e.g. DSP converts all FE hw params to run at fixed rate of 48k, 16bit, stereo for
+DAI0. This means all FE hw_params have to be fixed in the machine driver for
+DAI0 so that the DAI is running at desired configuration regardless of the FE
+configuration.
+
+static int dai0_fixup(struct snd_soc_pcm_runtime *rtd,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_interval *rate = hw_param_interval(params,
+ SNDRV_PCM_HW_PARAM_RATE);
+ struct snd_interval *channels = hw_param_interval(params,
+ SNDRV_PCM_HW_PARAM_CHANNELS);
+
+ /* The DSP will covert the FE rate to 48k, stereo */
+ rate->min = rate->max = 48000;
+ channels->min = channels->max = 2;
+
+ /* set DAI0 to 16 bit */
+ snd_mask_set(&params->masks[SNDRV_PCM_HW_PARAM_FORMAT -
+ SNDRV_PCM_HW_PARAM_FIRST_MASK],
+ SNDRV_PCM_FORMAT_S16_LE);
+ return 0;
+}
+
+The other PCM operation are the same as for regular DAI links. Use as necessary.
+
+
+3 Widget graph connections
+--------------------------
+
+The BE DAI links will normally be connected to the graph at initialisation time
+by the ASoC DAPM core. However, if the BE codec or BE DAI is a dummy then this
+has to be set explicitly in the driver :-
+
+/* BE for codec Headset - DAI0 is dummy and managed by DSP FW */
+{"DAI0 CODEC IN", NULL, "AIF1 Capture"},
+{"AIF1 Playback", NULL, "DAI0 CODEC OUT"},
+
+
+Writing a DPCM DSP driver
+=========================
+
+The DPCM DSP driver looks much like a standard platform class ASoC driver
+combined with elements from a codec class driver. A DSP platform driver must
+implement :-
+
+ 1) Front End PCM DAIs - i.e. struct snd_soc_dai_driver.
+
+ 2) DAPM graph showing DSP audio routing from FE DAIs to BEs.
+
+ 3) DAPM widgets from DSP graph.
+
+ 4) Mixers for gains, routing, etc.
+
+ 5) DMA configuration.
+
+ 6) BE AIF widgets.
+
+Items 6 is important for routing the audio outside of the DSP. AIF need to be
+defined for each BE and each stream direction. e.g for BE DAI0 above we would
+have :-
+
+SND_SOC_DAPM_AIF_IN("DAI0 RX", NULL, 0, SND_SOC_NOPM, 0, 0),
+SND_SOC_DAPM_AIF_OUT("DAI0 TX", NULL, 0, SND_SOC_NOPM, 0, 0),
+
+The BE AIF are used to connect the DSP graph to the graphs for the other
+component drivers (e.g. codec graph).
+
+
+Hostless PCM streams
+====================
+
+A hostless PCM stream is a stream that is not routed through the host CPU. An
+example of this would be a phone call from handset to modem.
+
+
+ *************
+PCM0 <------------> * * <----DAI0-----> Codec Headset
+ * *
+PCM1 <------------> * * <====DAI1=====> Codec Speakers/Mic
+ * DSP *
+PCM2 <------------> * * <====DAI2=====> MODEM
+ * *
+PCM3 <------------> * * <----DAI3-----> BT
+ * *
+ * * <----DAI4-----> DMIC
+ * *
+ * * <----DAI5-----> FM
+ *************
+
+In this case the PCM data is routed via the DSP. The host CPU in this use case
+is only used for control and can sleep during the runtime of the stream.
+
+The host can control the hostless link either by :-
+
+ 1) Configuring the link as a CODEC <-> CODEC style link. In this case the link
+ is enabled or disabled by the state of the DAPM graph. This usually means
+ there is a mixer control that can be used to connect or disconnect the path
+ between both DAIs.
+
+ 2) Hostless FE. This FE has a virtual connection to the BE DAI links on the DAPM
+ graph. Control is then carried out by the FE as regualar PCM operations.
+ This method gives more control over the DAI links, but requires much more
+ userspace code to control the link. Its recommended to use CODEC<->CODEC
+ unless your HW needs more fine grained sequencing of the PCM ops.
+
+
+CODEC <-> CODEC link
+--------------------
+
+This DAI link is enabled when DAPM detects a valid path within the DAPM graph.
+The machine driver sets some additional parameters to the DAI link i.e.
+
+static const struct snd_soc_pcm_stream dai_params = {
+ .formats = SNDRV_PCM_FMTBIT_S32_LE,
+ .rate_min = 8000,
+ .rate_max = 8000,
+ .channels_min = 2,
+ .channels_max = 2,
+};
+
+static struct snd_soc_dai_link dais[] = {
+ < ... more DAI links above ... >
+ {
+ .name = "MODEM",
+ .stream_name = "MODEM",
+ .cpu_dai_name = "dai2",
+ .codec_dai_name = "modem-aif1",
+ .codec_name = "modem",
+ .dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF
+ | SND_SOC_DAIFMT_CBM_CFM,
+ .params = &dai_params,
+ }
+ < ... more DAI links here ... >
+
+These parameters are used to configure the DAI hw_params() when DAPM detects a
+valid path and then calls the PCM operations to start the link. DAPM will also
+call the appropriate PCM operations to disable the DAI when the path is no
+longer valid.
+
+
+Hostless FE
+-----------
+
+The DAI link(s) are enabled by a FE that does not read or write any PCM data.
+This means creating a new FE that is connected with a virtual path to both
+DAI links. The DAI links will be started when the FE PCM is started and stopped
+when the FE PCM is stopped. Note that the FE PCM cannot read or write data in
+this configuration.
+
+
diff --git a/Documentation/sound/alsa/soc/codec.txt b/Documentation/sound/alsa/soc/codec.txt
index bce23a4a7875..db5f9c9ae149 100644
--- a/Documentation/sound/alsa/soc/codec.txt
+++ b/Documentation/sound/alsa/soc/codec.txt
@@ -1,22 +1,23 @@
-ASoC Codec Driver
-=================
+ASoC Codec Class Driver
+=======================
-The codec driver is generic and hardware independent code that configures the
-codec to provide audio capture and playback. It should contain no code that is
-specific to the target platform or machine. All platform and machine specific
-code should be added to the platform and machine drivers respectively.
+The codec class driver is generic and hardware independent code that configures
+the codec, FM, MODEM, BT or external DSP to provide audio capture and playback.
+It should contain no code that is specific to the target platform or machine.
+All platform and machine specific code should be added to the platform and
+machine drivers respectively.
-Each codec driver *must* provide the following features:-
+Each codec class driver *must* provide the following features:-
1) Codec DAI and PCM configuration
- 2) Codec control IO - using I2C, 3 Wire(SPI) or both APIs
+ 2) Codec control IO - using RegMap API
3) Mixers and audio controls
4) Codec audio operations
+ 5) DAPM description.
+ 6) DAPM event handler.
Optionally, codec drivers can also provide:-
- 5) DAPM description.
- 6) DAPM event handler.
7) DAC Digital mute control.
Its probably best to use this guide in conjunction with the existing codec
@@ -64,26 +65,9 @@ struct snd_soc_dai_driver wm8731_dai = {
2 - Codec control IO
--------------------
The codec can usually be controlled via an I2C or SPI style interface
-(AC97 combines control with data in the DAI). The codec drivers provide
-functions to read and write the codec registers along with supplying a
-register cache:-
-
- /* IO control data and register cache */
- void *control_data; /* codec control (i2c/3wire) data */
- void *reg_cache;
-
-Codec read/write should do any data formatting and call the hardware
-read write below to perform the IO. These functions are called by the
-core and ALSA when performing DAPM or changing the mixer:-
-
- unsigned int (*read)(struct snd_soc_codec *, unsigned int);
- int (*write)(struct snd_soc_codec *, unsigned int, unsigned int);
-
-Codec hardware IO functions - usually points to either the I2C, SPI or AC97
-read/write:-
-
- hw_write_t hw_write;
- hw_read_t hw_read;
+(AC97 combines control with data in the DAI). The codec driver should use the
+Regmap API for all codec IO. Please see include/linux/regmap.h and existing
+codec drivers for example regmap usage.
3 - Mixers and audio controls
@@ -127,7 +111,7 @@ Defines a stereo enumerated control
4 - Codec Audio Operations
--------------------------
-The codec driver also supports the following ALSA operations:-
+The codec driver also supports the following ALSA PCM operations:-
/* SoC audio ops */
struct snd_soc_ops {
diff --git a/Documentation/sound/alsa/soc/dapm.txt b/Documentation/sound/alsa/soc/dapm.txt
index 05bf5a0eee41..7dfd88ce31ac 100644
--- a/Documentation/sound/alsa/soc/dapm.txt
+++ b/Documentation/sound/alsa/soc/dapm.txt
@@ -21,7 +21,7 @@ level power systems.
There are 4 power domains within DAPM
- 1. Codec domain - VREF, VMID (core codec and audio power)
+ 1. Codec bias domain - VREF, VMID (core codec and audio power)
Usually controlled at codec probe/remove and suspend/resume, although
can be set at stream time if power is not needed for sidetone, etc.
@@ -63,14 +63,22 @@ Audio DAPM widgets fall into a number of types:-
o Line - Line Input/Output (and optional Jack)
o Speaker - Speaker
o Supply - Power or clock supply widget used by other widgets.
+ o Regulator - External regulator that supplies power to audio components.
+ o Clock - External clock that supplies clock to audio componnents.
+ o AIF IN - Audio Interface Input (with TDM slot mask).
+ o AIF OUT - Audio Interface Output (with TDM slot mask).
+ o Siggen - Signal Generator.
+ o DAI IN - Digital Audio Interface Input.
+ o DAI OUT - Digital Audio Interface Output.
+ o DAI Link - DAI Link between two DAI structures */
o Pre - Special PRE widget (exec before all others)
o Post - Special POST widget (exec after all others)
(Widgets are defined in include/sound/soc-dapm.h)
-Widgets are usually added in the codec driver and the machine driver. There are
-convenience macros defined in soc-dapm.h that can be used to quickly build a
-list of widgets of the codecs and machines DAPM widgets.
+Widgets can be added to the sound card by any of the component driver types.
+There are convenience macros defined in soc-dapm.h that can be used to quickly
+build a list of widgets of the codecs and machines DAPM widgets.
Most widgets have a name, register, shift and invert. Some widgets have extra
parameters for stream name and kcontrols.
@@ -80,11 +88,13 @@ parameters for stream name and kcontrols.
-------------------------
Stream Widgets relate to the stream power domain and only consist of ADCs
-(analog to digital converters) and DACs (digital to analog converters).
+(analog to digital converters), DACs (digital to analog converters),
+AIF IN and AIF OUT.
Stream widgets have the following format:-
SND_SOC_DAPM_DAC(name, stream name, reg, shift, invert),
+SND_SOC_DAPM_AIF_IN(name, stream, slot, reg, shift, invert)
NOTE: the stream name must match the corresponding stream name in your codec
snd_soc_codec_dai.
@@ -94,6 +104,11 @@ e.g. stream widgets for HiFi playback and capture
SND_SOC_DAPM_DAC("HiFi DAC", "HiFi Playback", REG, 3, 1),
SND_SOC_DAPM_ADC("HiFi ADC", "HiFi Capture", REG, 2, 1),
+e.g. stream widgets for AIF
+
+SND_SOC_DAPM_AIF_IN("AIF1RX", "AIF1 Playback", 0, SND_SOC_NOPM, 0, 0),
+SND_SOC_DAPM_AIF_OUT("AIF1TX", "AIF1 Capture", 0, SND_SOC_NOPM, 0, 0),
+
2.2 Path Domain Widgets
-----------------------
@@ -121,12 +136,14 @@ If you dont want the mixer elements prefixed with the name of the mixer widget,
you can use SND_SOC_DAPM_MIXER_NAMED_CTL instead. the parameters are the same
as for SND_SOC_DAPM_MIXER.
-2.3 Platform/Machine domain Widgets
------------------------------------
+
+2.3 Machine domain Widgets
+--------------------------
Machine widgets are different from codec widgets in that they don't have a
codec register bit associated with them. A machine widget is assigned to each
-machine audio component (non codec) that can be independently powered. e.g.
+machine audio component (non codec or DSP) that can be independently
+powered. e.g.
o Speaker Amp
o Microphone Bias
@@ -146,12 +163,12 @@ static int spitz_mic_bias(struct snd_soc_dapm_widget* w, int event)
SND_SOC_DAPM_MIC("Mic Jack", spitz_mic_bias),
-2.4 Codec Domain
-----------------
+2.4 Codec (BIAS) Domain
+-----------------------
-The codec power domain has no widgets and is handled by the codecs DAPM event
-handler. This handler is called when the codec powerstate is changed wrt to any
-stream event or by kernel PM events.
+The codec bias power domain has no widgets and is handled by the codecs DAPM
+event handler. This handler is called when the codec powerstate is changed wrt
+to any stream event or by kernel PM events.
2.5 Virtual Widgets
@@ -169,15 +186,16 @@ After all the widgets have been defined, they can then be added to the DAPM
subsystem individually with a call to snd_soc_dapm_new_control().
-3. Codec Widget Interconnections
-================================
+3. Codec/DSP Widget Interconnections
+====================================
-Widgets are connected to each other within the codec and machine by audio paths
-(called interconnections). Each interconnection must be defined in order to
-create a map of all audio paths between widgets.
+Widgets are connected to each other within the codec, platform and machine by
+audio paths (called interconnections). Each interconnection must be defined in
+order to create a map of all audio paths between widgets.
-This is easiest with a diagram of the codec (and schematic of the machine audio
-system), as it requires joining widgets together via their audio signal paths.
+This is easiest with a diagram of the codec or DSP (and schematic of the machine
+audio system), as it requires joining widgets together via their audio signal
+paths.
e.g., from the WM8731 output mixer (wm8731.c)
@@ -247,16 +265,9 @@ machine and includes the codec. e.g.
o Mic Jack
o Codec Pins
-When a codec pin is NC it can be marked as not used with a call to
-
-snd_soc_dapm_set_endpoint(codec, "Widget Name", 0);
-
-The last argument is 0 for inactive and 1 for active. This way the pin and its
-input widget will never be powered up and consume power.
-
-This also applies to machine widgets. e.g. if a headphone is connected to a
-jack then the jack can be marked active. If the headphone is removed, then
-the headphone jack can be marked inactive.
+Endpoints are added to the DAPM graph so that their usage can be determined in
+order to save power. e.g. NC codecs pins will be switched OFF, unconnected
+jacks can also be switched OFF.
5 DAPM Widget Events
diff --git a/Documentation/sound/alsa/soc/machine.txt b/Documentation/sound/alsa/soc/machine.txt
index d50c14df3411..74056dba52be 100644
--- a/Documentation/sound/alsa/soc/machine.txt
+++ b/Documentation/sound/alsa/soc/machine.txt
@@ -1,8 +1,10 @@
ASoC Machine Driver
===================
-The ASoC machine (or board) driver is the code that glues together the platform
-and codec drivers.
+The ASoC machine (or board) driver is the code that glues together all the
+component drivers (e.g. codecs, platforms and DAIs). It also describes the
+relationships between each componnent which include audio paths, GPIOs,
+interrupts, clocking, jacks and voltage regulators.
The machine driver can contain codec and platform specific code. It registers
the audio subsystem with the kernel as a platform device and is represented by
diff --git a/Documentation/sound/alsa/soc/platform.txt b/Documentation/sound/alsa/soc/platform.txt
index d57efad37e0a..3a08a2c9150c 100644
--- a/Documentation/sound/alsa/soc/platform.txt
+++ b/Documentation/sound/alsa/soc/platform.txt
@@ -1,9 +1,9 @@
ASoC Platform Driver
====================
-An ASoC platform driver can be divided into audio DMA and SoC DAI configuration
-and control. The platform drivers only target the SoC CPU and must have no board
-specific code.
+An ASoC platform driver class can be divided into audio DMA drivers, SoC DAI
+drivers and DSP drivers. The platform drivers only target the SoC CPU and must
+have no board specific code.
Audio DMA
=========
@@ -64,3 +64,16 @@ Each SoC DAI driver must provide the following features:-
5) Suspend and resume (optional)
Please see codec.txt for a description of items 1 - 4.
+
+
+SoC DSP Drivers
+===============
+
+Each SoC DSP driver usually supplies the following features :-
+
+ 1) DAPM graph
+ 2) Mixer controls
+ 3) DMA IO to/from DSP buffers (if applicable)
+ 4) Definition of DSP front end (FE) PCM devices.
+
+Please see DPCM.txt for a description of item 4.