1.. SPDX-License-Identifier: GPL-2.0-only
2
3========================================================================
4Audio drivers for Cirrus Logic CS35L54/56/57/63 Boosted Smart Amplifiers
5========================================================================
6:Copyright: 2025 Cirrus Logic, Inc. and
7                 Cirrus Logic International Semiconductor Ltd.
8
9Contact: patches@opensource.cirrus.com
10
11Summary
12=======
13
14The high-level summary of this document is:
15
16**If you have a laptop that uses CS35L54/56/57/63 amplifiers but audio is not
17working, DO NOT ATTEMPT TO USE FIRMWARE AND SETTINGS FROM ANOTHER LAPTOP,
18EVEN IF THAT LAPTOP SEEMS SIMILAR.**
19
20The CS35L54/56/57/63 amplifiers must be correctly configured for the power
21supply voltage, speaker impedance, maximum speaker voltage/current, and
22other external hardware connections.
23
24The amplifiers feature advanced boost technology that increases the voltage
25used to drive the speakers, while proprietary speaker protection algorithms
26allow these boosted amplifiers to push the limits of the speakers without
27causing damage. These **must** be configured correctly.
28
29Supported Cirrus Logic amplifiers
30---------------------------------
31
32The cs35l56 drivers support:
33
34* CS35L54
35* CS35L56
36* CS35L57
37* CS35L63
38
39There are two drivers in the kernel
40
41*For systems using SoundWire*: sound/soc/codecs/cs35l56.c and associated files
42
43*For systems using HDA*: sound/pci/hda/cs35l56_hda.c
44
45Firmware
46========
47
48The amplifier is controlled and managed by firmware running on the internal
49DSP. Firmware files are essential to enable the full capabilities of the
50amplifier.
51
52Firmware is distributed in the linux-firmware repository:
53https://gitlab.com/kernel-firmware/linux-firmware.git
54
55On most SoundWire systems the amplifier has a default minimum capability to
56produce audio. However this will be
57
58* at low volume, to protect the speakers, since the speaker specifications
59  and power supply voltages are unknown.
60* a mono mix of left and right channels.
61
62On some SoundWire systems that have both CS42L43 and CS35L56/57 the CS35L56/57
63receive their audio from the CS42L43 instead of directly from the host
64SoundWire interface. These systems can be identified by the CS42L43 showing
65in dmesg as a SoundWire device, but the CS35L56/57 as SPI. On these systems
66the firmware is *mandatory* to enable receiving the audio from the CS42L43.
67
68On HDA systems the firmware is *mandatory* to enable HDA bridge mode. There
69will not be any audio from the amplifiers without firmware.
70
71Cirrus Logic firmware files
72---------------------------
73
74Each amplifier requires two firmware files. One file has a .wmfw suffix, the
75other has a .bin suffix.
76
77The firmware is customized by the OEM to match the hardware of each laptop,
78and the firmware is specific to that laptop. Because of this, there are many
79firmware files in linux-firmware for these amplifiers. Firmware files are
80**not interchangeable between laptops**.
81
82Cirrus Logic submits files for known laptops to the upstream linux-firmware
83repository. Providing Cirrus Logic is aware of a particular laptop and has
84permission from the manufacturer to publish the firmware, it will be pushed
85to linux-firmware. You may need to upgrade to a newer release of
86linux-firmware to obtain the firmware for your laptop.
87
88**Important:** the Makefile for linux-firmware creates symlinks that are listed
89in the WHENCE file. These symlinks are required for the CS35L56 driver to be
90able to load the firmware.
91
92How do I know which firmware file I should have?
93~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
94All firmware file names are qualified with a unique "system ID". On normal
95x86 PCs with PCI audio this is the Vendor Subsystem ID (SSID) of the host
96PCI audio interface.
97
98The SSID can be viewed using the lspci tool::
99
100  lspci -v -nn | grep -A2 -i audio
101  0000:00:1f.3 Audio device [0403]: Intel Corporation Meteor Lake-P HD Audio Controller [8086:7e28]
102  Subsystem: Dell Meteor Lake-P HD Audio Controller [1028:0c63]
103
104In this example the SSID is 10280c63.
105
106The format of the firmware file names is:
107
108SoundWire (except CS35L56 Rev B0):
109    cs35lxx-b0-dsp1-misc-SSID[-spkidX]-l?u?
110
111SoundWire CS35L56 Rev B0:
112    cs35lxx-b0-dsp1-misc-SSID[-spkidX]-ampN
113
114Non-SoundWire (HDA and I2S):
115    cs35lxx-b0-dsp1-misc-SSID[-spkidX]-ampN
116
117Where:
118
119  * cs35lxx-b0 is the amplifier model and silicon revision. This information
120    is logged by the driver during initialization.
121  * SSID is the 8-digit hexadecimal SSID value.
122  * l?u? is the physical address on the SoundWire bus of the amp this
123    file applies to.
124  * ampN is the amplifier number (for example amp1). This is the same as
125    the prefix on the ALSA control names except that it is always lower-case
126    in the file name.
127  * spkidX is an optional part, used for laptops that have firmware
128    configurations for different makes and models of internal speakers.
129
130The CS35L56 Rev B0 continues to use the old filename scheme because a
131large number of firmware files have already been published with these
132names.
133
134Sound Open Firmware and ALSA topology files
135-------------------------------------------
136
137All SoundWire systems will require a Sound Open Firmware (SOF) for the
138host CPU audio DSP, together with an ALSA topology file (.tplg).
139
140The SOF firmware will usually be provided by the manufacturer of the host
141CPU (i.e. Intel or AMD). The .tplg file is normally part of the SOF firmware
142release.
143
144SOF binary builds are available from: https://github.com/thesofproject/sof-bin/releases
145
146The main SOF source is here: https://github.com/thesofproject
147
148ALSA-ucm configurations
149-----------------------
150Typically an appropriate ALSA-ucm configuration file is needed for
151use-case managers and audio servers such as PipeWire.
152
153Configuration files are available from the alsa-ucm-conf repository:
154https://git.alsa-project.org/?p=alsa-ucm-conf.git
155
156Kernel log messages
157===================
158
159SoundWire
160---------
161A successful initialization will look like this (this will be repeated for
162each amplifier)::
163
164  [ 7.568374] cs35l56 sdw:0:0:01fa:3556:01:0: supply VDD_P not found, using dummy regulator
165  [ 7.605208] cs35l56 sdw:0:0:01fa:3556:01:0: supply VDD_IO not found, using dummy regulator
166  [ 7.605313] cs35l56 sdw:0:0:01fa:3556:01:0: supply VDD_A not found, using dummy regulator
167  [ 7.939279] cs35l56 sdw:0:0:01fa:3556:01:0: Cirrus Logic CS35L56 Rev B0 OTP3 fw:3.4.4 (patched=0)
168  [ 7.947844] cs35l56 sdw:0:0:01fa:3556:01:0: Slave 4 state check1: UNATTACHED, status was 1
169  [ 8.740280] cs35l56 sdw:0:0:01fa:3556:01:0: supply VDD_B not found, using dummy regulator
170  [ 8.740552] cs35l56 sdw:0:0:01fa:3556:01:0: supply VDD_AMP not found, using dummy regulator
171  [ 9.242164] cs35l56 sdw:0:0:01fa:3556:01:0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx.wmfw: format 3 timestamp 0x66b2b872
172  [ 9.242173] cs35l56 sdw:0:0:01fa:3556:01:0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx.wmfw: Tue 05 Dec 2023 21:37:21 GMT Standard Time
173  [ 9.991709] cs35l56 sdw:0:0:01fa:3556:01:0: DSP1: Firmware: 1a00d6 vendor: 0x2 v3.11.23, 41 algorithms
174  [10.039098] cs35l56 sdw:0:0:01fa:3556:01:0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx-amp1.bin: v3.11.23
175  [10.879235] cs35l56 sdw:0:0:01fa:3556:01:0: Slave 4 state check1: UNATTACHED, status was 1
176  [11.401536] cs35l56 sdw:0:0:01fa:3556:01:0: Calibration applied
177
178HDA
179---
180A successful initialization will look like this (this will be repeated for
181each amplifier)::
182
183  [ 6.306475] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: Cirrus Logic CS35L56 Rev B0 OTP3 fw:3.4.4 (patched=0)
184  [ 6.613892] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: DSP system name: 'xxxxxxxx', amp name: 'AMP1'
185  [ 8.266660] snd_hda_codec_cs8409 ehdaudio0D0: bound i2c-CSC3556:00-cs35l56-hda.0 (ops cs35l56_hda_comp_ops [snd_hda_scodec_cs35l56])
186  [ 8.287525] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx.wmfw: format 3 timestamp 0x66b2b872
187  [ 8.287528] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx.wmfw: Tue 05 Dec 2023 21:37:21 GMT Standard Time
188  [ 9.984335] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: DSP1: Firmware: 1a00d6 vendor: 0x2 v3.11.23, 41 algorithms
189  [10.085797] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx-amp1.bin: v3.11.23
190  [10.655237] cs35l56-hda i2c-CSC3556:00-cs35l56-hda.0: Calibration applied
191
192Important messages
193~~~~~~~~~~~~~~~~~~
194Cirrus Logic CS35L56 Rev B0 OTP3 fw:3.4.4 (patched=0)
195  Shows that the driver has been able to read device ID registers from the
196  amplifier.
197
198    * The actual amplifier type and silicon revision (CS35L56 B0 in this
199      example) is shown, as read from the amplifier identification registers.
200    * (patched=0) is normal, and indicates that the amplifier has been hard
201      reset and is running default ROM firmware.
202    * (patched=1) means that something has previously downloaded firmware
203      to the amplifier and the driver does not have control of the RESET
204      signal to be able to replace this preloaded firmware. This is normal
205      for systems where the BIOS downloads firmware to the amplifiers
206      before OS boot.
207      This status can also be seen if the cs35l56 kernel module is unloaded
208      and reloaded on a system where the driver does not have control of
209      RESET. SoundWire systems typically do not give the driver control of
210      RESET and only a BIOS (re)boot can reset the amplifiers.
211
212DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx.wmfw
213  Shows that a .wmfw firmware file was found and downloaded.
214
215DSP1: cirrus/cs35l56-b0-dsp1-misc-xxxxxxxx-amp1.bin
216  Shows that a .bin firmware file was found and downloaded.
217
218Calibration applied
219  Factory calibration data in EFI was written to the amplifier.
220
221Error messages
222==============
223This section explains some of the error messages that the driver can log.
224
225Algorithm coefficient version %d.%d.%d but expected %d.%d.%d
226  The version of the .bin file content does not match the loaded firmware.
227  Caused by mismatched .wmfw and .bin file, or .bin file was found but
228  .wmfw was not.
229
230No %s for algorithm %x
231  The version of the .bin file content does not match the loaded firmware.
232  Caused by mismatched .wmfw and .bin file, or .bin file was found but
233  .wmfw was not.
234
235.bin file required but not found
236  HDA driver did not find a .bin file that matches this hardware.
237
238Calibration disabled due to missing firmware controls
239  Driver was not able to write EFI calibration data to firmware registers.
240  This typically means that either:
241
242    * The driver did not find a suitable wmfw for this hardware, or
243    * The amplifier has already been patched with firmware by something
244      previously, and the driver does not have control of a hard RESET line
245      to be able to reset the amplifier and download the firmware files it
246      found. This situation is indicated by the device identification
247      string in the kernel log shows "(patched=1)"
248
249Failed to write calibration
250  Same meaning and cause as "Calibration disabled due to missing firmware
251  controls"
252
253Failed to read calibration data from EFI
254  Factory calibration data in EFI is missing, empty or corrupt.
255  This is most likely to be cause by accidentally deleting the file from
256  the EFI filesystem.
257
258No calibration for silicon ID
259  The factory calibration data in EFI does not match this hardware.
260  The most likely cause is that an amplifier has been replaced on the
261  motherboard without going through manufacturer calibration process to
262  generate calibration data for the new amplifier.
263
264Did not find any buses for CSCxxxx
265  Only on HDA systems. The HDA codec driver found an ACPI entry for
266  Cirrus Logic companion amps, but could not enumerate the ACPI entries for
267  the I2C/SPI buses. The most likely cause of this is that:
268
269    * The relevant bus driver (I2C or SPI) is not part of the kernel.
270    * The HDA codec driver was built-in to the kernel but the I2C/SPI
271      bus driver is a module and so the HDA codec driver cannot call the
272      bus driver functions.
273
274init_completion timed out
275  The SoundWire bus controller (host end) did not enumerate the amplifier.
276  In other words, the ACPI says there is an amplifier but for some reason
277  it was not detected on the bus.
278
279No AF01 node
280  Indicates an error in ACPI. A SoundWire system should have a Device()
281  node named "AF01" but it was not found.
282
283Failed to get spk-id-gpios
284  ACPI says that the driver should request a GPIO but the driver was not
285  able to get that GPIO. The most likely cause is that the kernel does not
286  include the correct GPIO or PINCTRL driver for this system.
287
288Failed to read spk-id
289  ACPI says that the driver should request a GPIO but the driver was not
290  able to read that GPIO.
291
292Unexpected spk-id element count
293  AF01 contains more speaker ID GPIO entries than the driver supports
294
295Overtemp error
296  Amplifier overheat protection was triggered and the amplifier shut down
297  to protect itself.
298
299Amp short error
300  Amplifier detected a short-circuit on the speaker output pins and shut
301  down for protection. This would normally indicate a damaged speaker.
302
303Hibernate wake failed
304  The driver tried to wake the amplifier from its power-saving state but
305  did not see the expected responses from the amplifier. This can be caused
306  by using firmware that does not match the hardware.
307