SR_PRIV int cv_set_samplerate(const struct sr_dev_inst *sdi, uint64_t samplerate)
{
struct dev_context *devc;
/* Note: Caller checked that sdi and sdi->priv != NULL. */
devc = sdi->priv;
sr_spew("Trying to set samplerate to %" PRIu64 "Hz.", samplerate);
cv_fill_samplerates_if_needed(sdi);
/* Check if this is a samplerate supported by the hardware. */
if (!is_valid_samplerate(sdi, samplerate)) {
sr_dbg("Failed to set invalid samplerate (%" PRIu64 "Hz).",
samplerate);
return SR_ERR;
}
devc->cur_samplerate = samplerate;
sr_dbg("Samplerate set to %" PRIu64 "Hz.", devc->cur_samplerate);
return SR_OK;
}
/**
* Convert a samplerate (in Hz) to the 'divcount' value the LA8 wants.
*
* LA8 hardware: sample period = (divcount + 1) * 10ns.
* Min. value for divcount: 0x00 (10ns sample period, 100MHz samplerate).
* Max. value for divcount: 0xfe (2550ns sample period, 392.15kHz samplerate).
*
* @param samplerate The samplerate in Hz.
* @return The divcount value as needed by the hardware, or 0xff upon errors.
*/
SR_PRIV uint8_t samplerate_to_divcount(uint64_t samplerate)
{
if (samplerate == 0) {
sr_err("%s: samplerate was 0.", __func__);
return 0xff;
}
if (!is_valid_samplerate(samplerate)) {
sr_err("%s: Can't get divcount, samplerate invalid.", __func__);
return 0xff;
}
return (SR_MHZ(100) / samplerate) - 1;
}
/**
* Convert a samplerate (in Hz) to the 'divcount' value the device wants.
*
* The divcount value can be 0x00 - 0xfe (0xff is not valid).
*
* LA8:
* sample period = (divcount + 1) * 10ns.
* divcount = 0x00: 10ns period, 100MHz samplerate.
* divcount = 0xfe: 2550ns period, 392.15kHz samplerate.
*
* LA16:
* sample period = (divcount + 1) * 5ns.
* divcount = 0x00: 5ns period, 200MHz samplerate.
* divcount = 0xfe: 1275ns period, ~784.31kHz samplerate.
*
* @param sdi Device instance.
* @param samplerate The samplerate in Hz.
*
* @return The divcount value as needed by the hardware, or 0xff upon errors.
*/
SR_PRIV uint8_t cv_samplerate_to_divcount(const struct sr_dev_inst *sdi,
uint64_t samplerate)
{
struct dev_context *devc;
devc = sdi->priv;
if (samplerate == 0) {
sr_err("Can't convert invalid samplerate of 0 Hz.");
return 0xff;
}
if (!is_valid_samplerate(sdi, samplerate)) {
sr_err("Can't get divcount, samplerate invalid.");
return 0xff;
}
return (devc->prof->max_samplerate / samplerate) - 1;
}
