Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | |
| 2 | Documentation for the Cirrus Logic/Crystal SoundFusion cs46xx/cs4280 audio |
| 3 | controller chips (2001/05/11) |
| 4 | |
| 5 | The cs46xx audio driver supports the DSP line of Cirrus controllers. |
| 6 | Specifically, the cs4610, cs4612, cs4614, cs4622, cs4624, cs4630 and the cs4280 |
| 7 | products. This driver uses the generic ac97_codec driver for AC97 codec |
| 8 | support. |
| 9 | |
| 10 | |
| 11 | Features: |
| 12 | |
| 13 | Full Duplex Playback/Capture supported from 8k-48k. |
| 14 | 16Bit Signed LE & 8Bit Unsigned, with Mono or Stereo supported. |
| 15 | |
| 16 | APM/PM - 2.2.x PM is enabled and functional. APM can also |
| 17 | be enabled for 2.4.x by modifying the CS46XX_ACPI_SUPPORT macro |
| 18 | definition. |
| 19 | |
| 20 | DMA playback buffer size is configurable from 16k (defaultorder=2) up to 2Meg |
| 21 | (defaultorder=11). DMA capture buffer size is fixed at a single 4k page as |
| 22 | two 2k fragments. |
| 23 | |
| 24 | MMAP seems to work well with QuakeIII, and test XMMS plugin. |
| 25 | |
| 26 | Myth2 works, but the polling logic is not fully correct, but is functional. |
| 27 | |
| 28 | The 2.4.4-ac6 gameport code in the cs461x joystick driver has been tested |
| 29 | with a Microsoft Sidewinder joystick (cs461x.o and sidewinder.o). This |
| 30 | audio driver must be loaded prior to the joystick driver to enable the |
| 31 | DSP task image supporting the joystick device. |
| 32 | |
| 33 | |
| 34 | Limitations: |
| 35 | |
| 36 | SPDIF is currently not supported. |
| 37 | |
| 38 | Primary codec support only. No secondary codec support is implemented. |
| 39 | |
| 40 | |
| 41 | |
| 42 | NOTES: |
| 43 | |
| 44 | Hercules Game Theatre XP - the EGPIO2 pin controls the external Amp, |
| 45 | and has been tested. |
| 46 | Module parameter hercules_egpio_disable set to 1, will force a 0 to EGPIODR |
| 47 | to disable the external amplifier. |
| 48 | |
| 49 | VTB Santa Cruz - the GPIO7/GPIO8 on the Secondary Codec control |
| 50 | the external amplifier for the "back" speakers, since we do not |
| 51 | support the secondary codec then this external amp is not |
| 52 | turned on. The primary codec external amplifier is supported but |
| 53 | note that the AC97 EAPD bit is inverted logic (amp_voyetra()). |
| 54 | |
| 55 | DMA buffer size - there are issues with many of the Linux applications |
| 56 | concerning the optimal buffer size. Several applications request a |
| 57 | certain fragment size and number and then do not verify that the driver |
| 58 | has the ability to support the requested configuration. |
| 59 | SNDCTL_DSP_SETFRAGMENT ioctl is used to request a fragment size and |
| 60 | number of fragments. Some applications exit if an error is returned |
| 61 | on this particular ioctl. Therefore, in alignment with the other OSS audio |
| 62 | drivers, no error is returned when a SETFRAGs IOCTL is received, but the |
| 63 | values passed from the app are not used in any buffer calculation |
| 64 | (ossfragshift/ossmaxfrags are not used). |
| 65 | Use the "defaultorder=N" module parameter to change the buffer size if |
| 66 | you have an application that requires a specific number of fragments |
| 67 | or a specific buffer size (see below). |
| 68 | |
| 69 | Debug Interface |
| 70 | --------------- |
| 71 | There is an ioctl debug interface to allow runtime modification of the |
| 72 | debug print levels. This debug interface code can be disabled from the |
| 73 | compilation process with commenting the following define: |
| 74 | #define CSDEBUG_INTERFACE 1 |
| 75 | There is also a debug print methodolgy to select printf statements from |
| 76 | different areas of the driver. A debug print level is also used to allow |
| 77 | additional printfs to be active. Comment out the following line in the |
| 78 | driver to disable compilation of the CS_DBGOUT print statements: |
| 79 | #define CSDEBUG 1 |
| 80 | |
| 81 | Please see the definitions for cs_debuglevel and cs_debugmask for additional |
| 82 | information on the debug levels and sections. |
| 83 | |
| 84 | There is also a csdbg executable to allow runtime manipulation of these |
| 85 | parameters. for a copy email: twoller@crystal.cirrus.com |
| 86 | |
| 87 | |
| 88 | |
| 89 | MODULE_PARMS definitions |
| 90 | ------------------------ |
| 91 | MODULE_PARM(defaultorder, "i"); |
| 92 | defaultorder=N |
| 93 | where N is a value from 1 to 12 |
| 94 | The buffer order determines the size of the dma buffer for the driver. |
| 95 | under Linux, a smaller buffer allows more responsiveness from many of the |
| 96 | applications (e.g. games). A larger buffer allows some of the apps (esound) |
| 97 | to not underrun the dma buffer as easily. As default, use 32k (order=3) |
| 98 | rather than 64k as some of the games work more responsively. |
| 99 | (2^N) * PAGE_SIZE = allocated buffer size |
| 100 | |
| 101 | MODULE_PARM(cs_debuglevel, "i"); |
| 102 | MODULE_PARM(cs_debugmask, "i"); |
| 103 | cs_debuglevel=N |
| 104 | cs_debugmask=0xMMMMMMMM |
| 105 | where N is a value from 0 (no debug printfs), to 9 (maximum) |
| 106 | 0xMMMMMMMM is a debug mask corresponding to the CS_xxx bits (see driver source). |
| 107 | |
| 108 | MODULE_PARM(hercules_egpio_disable, "i"); |
| 109 | hercules_egpio_disable=N |
| 110 | where N is a 0 (enable egpio), or a 1 (disable egpio support) |
| 111 | |
| 112 | MODULE_PARM(initdelay, "i"); |
| 113 | initdelay=N |
| 114 | This value is used to determine the millescond delay during the initialization |
| 115 | code prior to powering up the PLL. On laptops this value can be used to |
| 116 | assist with errors on resume, mostly with IBM laptops. Basically, if the |
| 117 | system is booted under battery power then the mdelay()/udelay() functions fail to |
| 118 | properly delay the required time. Also, if the system is booted under AC power |
| 119 | and then the power removed, the mdelay()/udelay() functions will not delay properly. |
| 120 | |
| 121 | MODULE_PARM(powerdown, "i"); |
| 122 | powerdown=N |
| 123 | where N is 0 (disable any powerdown of the internal blocks) or 1 (enable powerdown) |
| 124 | |
| 125 | |
| 126 | MODULE_PARM(external_amp, "i"); |
| 127 | external_amp=1 |
| 128 | if N is set to 1, then force enabling the EAPD support in the primary AC97 codec. |
| 129 | override the detection logic and force the external amp bit in the AC97 0x26 register |
| 130 | to be reset (0). EAPD should be 0 for powerup, and 1 for powerdown. The VTB Santa Cruz |
| 131 | card has inverted logic, so there is a special function for these cards. |
| 132 | |
| 133 | MODULE_PARM(thinkpad, "i"); |
| 134 | thinkpad=1 |
| 135 | if N is set to 1, then force enabling the clkrun functionality. |
| 136 | Currently, when the part is being used, then clkrun is disabled for the entire system, |
| 137 | but re-enabled when the driver is released or there is no outstanding open count. |
| 138 | |