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diff --git a/Documentation/video4linux/si4713.txt b/Documentation/video4linux/si4713.txt deleted file mode 100644 index 2ddc6b095..000000000 --- a/Documentation/video4linux/si4713.txt +++ /dev/null @@ -1,176 +0,0 @@ -Driver for I2C radios for the Silicon Labs Si4713 FM Radio Transmitters - -Copyright (c) 2009 Nokia Corporation -Contact: Eduardo Valentin <eduardo.valentin@nokia.com> - - -Information about the Device -============================ -This chip is a Silicon Labs product. It is a I2C device, currently on 0x63 address. -Basically, it has transmission and signal noise level measurement features. - -The Si4713 integrates transmit functions for FM broadcast stereo transmission. -The chip also allows integrated receive power scanning to identify low signal -power FM channels. - -The chip is programmed using commands and responses. There are also several -properties which can change the behavior of this chip. - -Users must comply with local regulations on radio frequency (RF) transmission. - -Device driver description -========================= -There are two modules to handle this device. One is a I2C device driver -and the other is a platform driver. - -The I2C device driver exports a v4l2-subdev interface to the kernel. -All properties can also be accessed by v4l2 extended controls interface, by -using the v4l2-subdev calls (g_ext_ctrls, s_ext_ctrls). - -The platform device driver exports a v4l2 radio device interface to user land. -So, it uses the I2C device driver as a sub device in order to send the user -commands to the actual device. Basically it is a wrapper to the I2C device driver. - -Applications can use v4l2 radio API to specify frequency of operation, mute state, -etc. But mostly of its properties will be present in the extended controls. - -When the v4l2 mute property is set to 1 (true), the driver will turn the chip off. - -Properties description -====================== - -The properties can be accessed using v4l2 extended controls. -Here is an output from v4l2-ctl util: -/ # v4l2-ctl -d /dev/radio0 --all -L -Driver Info: - Driver name : radio-si4713 - Card type : Silicon Labs Si4713 Modulator - Bus info : - Driver version: 0 - Capabilities : 0x00080800 - RDS Output - Modulator -Audio output: 0 (FM Modulator Audio Out) -Frequency: 1408000 (88.000000 MHz) -Video Standard = 0x00000000 -Modulator: - Name : FM Modulator - Capabilities : 62.5 Hz stereo rds - Frequency range : 76.0 MHz - 108.0 MHz - Subchannel modulation: stereo+rds - -User Controls - - mute (bool) : default=1 value=0 - -FM Radio Modulator Controls - - rds_signal_deviation (int) : min=0 max=90000 step=10 default=200 value=200 flags=slider - rds_program_id (int) : min=0 max=65535 step=1 default=0 value=0 - rds_program_type (int) : min=0 max=31 step=1 default=0 value=0 - rds_ps_name (str) : min=0 max=96 step=8 value='si4713 ' - rds_radio_text (str) : min=0 max=384 step=32 value='' - audio_limiter_feature_enabled (bool) : default=1 value=1 - audio_limiter_release_time (int) : min=250 max=102390 step=50 default=5010 value=5010 flags=slider - audio_limiter_deviation (int) : min=0 max=90000 step=10 default=66250 value=66250 flags=slider -audio_compression_feature_enabl (bool) : default=1 value=1 - audio_compression_gain (int) : min=0 max=20 step=1 default=15 value=15 flags=slider - audio_compression_threshold (int) : min=-40 max=0 step=1 default=-40 value=-40 flags=slider - audio_compression_attack_time (int) : min=0 max=5000 step=500 default=0 value=0 flags=slider - audio_compression_release_time (int) : min=100000 max=1000000 step=100000 default=1000000 value=1000000 flags=slider - pilot_tone_feature_enabled (bool) : default=1 value=1 - pilot_tone_deviation (int) : min=0 max=90000 step=10 default=6750 value=6750 flags=slider - pilot_tone_frequency (int) : min=0 max=19000 step=1 default=19000 value=19000 flags=slider - pre_emphasis_settings (menu) : min=0 max=2 default=1 value=1 - tune_power_level (int) : min=0 max=120 step=1 default=88 value=88 flags=slider - tune_antenna_capacitor (int) : min=0 max=191 step=1 default=0 value=110 flags=slider -/ # - -Here is a summary of them: - -* Pilot is an audible tone sent by the device. - -pilot_frequency - Configures the frequency of the stereo pilot tone. -pilot_deviation - Configures pilot tone frequency deviation level. -pilot_enabled - Enables or disables the pilot tone feature. - -* The si4713 device is capable of applying audio compression to the transmitted signal. - -acomp_enabled - Enables or disables the audio dynamic range control feature. -acomp_gain - Sets the gain for audio dynamic range control. -acomp_threshold - Sets the threshold level for audio dynamic range control. -acomp_attack_time - Sets the attack time for audio dynamic range control. -acomp_release_time - Sets the release time for audio dynamic range control. - -* Limiter setups audio deviation limiter feature. Once a over deviation occurs, -it is possible to adjust the front-end gain of the audio input and always -prevent over deviation. - -limiter_enabled - Enables or disables the limiter feature. -limiter_deviation - Configures audio frequency deviation level. -limiter_release_time - Sets the limiter release time. - -* Tuning power - -power_level - Sets the output power level for signal transmission. -antenna_capacitor - This selects the value of antenna tuning capacitor manually -or automatically if set to zero. - -* RDS related - -rds_ps_name - Sets the RDS ps name field for transmission. -rds_radio_text - Sets the RDS radio text for transmission. -rds_pi - Sets the RDS PI field for transmission. -rds_pty - Sets the RDS PTY field for transmission. - -* Region related - -preemphasis - sets the preemphasis to be applied for transmission. - -RNL -=== - -This device also has an interface to measure received noise level. To do that, you should -ioctl the device node. Here is an code of example: - -int main (int argc, char *argv[]) -{ - struct si4713_rnl rnl; - int fd = open("/dev/radio0", O_RDWR); - int rval; - - if (argc < 2) - return -EINVAL; - - if (fd < 0) - return fd; - - sscanf(argv[1], "%d", &rnl.frequency); - - rval = ioctl(fd, SI4713_IOC_MEASURE_RNL, &rnl); - if (rval < 0) - return rval; - - printf("received noise level: %d\n", rnl.rnl); - - close(fd); -} - -The struct si4713_rnl and SI4713_IOC_MEASURE_RNL are defined under -include/linux/platform_data/media/si4713.h. - -Stereo/Mono and RDS subchannels -=============================== - -The device can also be configured using the available sub channels for -transmission. To do that use S/G_MODULATOR ioctl and configure txsubchans properly. -Refer to the V4L2 API specification for proper use of this ioctl. - -Testing -======= -Testing is usually done with v4l2-ctl utility for managing FM tuner cards. -The tool can be found in v4l-dvb repository under v4l2-apps/util directory. - -Example for setting rds ps name: -# v4l2-ctl -d /dev/radio0 --set-ctrl=rds_ps_name="Dummy" - |