diff options
| -rw-r--r-- | drivers/staging/pi433/rf69.c | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/drivers/staging/pi433/rf69.c b/drivers/staging/pi433/rf69.c index e62e61ef4d27..d64df072d8e8 100644 --- a/drivers/staging/pi433/rf69.c +++ b/drivers/staging/pi433/rf69.c @@ -255,13 +255,25 @@ int rf69_set_deviation(struct spi_device *spi, u32 deviation) int retval; u64 f_reg; u64 f_step; + u32 bit_rate_reg; + u32 bit_rate; u8 msb; u8 lsb; u64 factor = 1000000; // to improve precision of calculation - // TODO: Dependency to bitrate - if (deviation < 600 || deviation > 500000) { - dev_dbg(&spi->dev, "set_deviation: illegal input param"); + // calculate bit rate + bit_rate_reg = rf69_read_reg(spi, REG_BITRATE_MSB) << 8; + bit_rate_reg |= rf69_read_reg(spi, REG_BITRATE_LSB); + bit_rate = F_OSC / bit_rate_reg; + + /* + * frequency deviation must exceed 600 Hz but not exceed + * 500kHz when taking bitrate dependency into consideration + * to ensure proper modulation + */ + if (deviation < 600 || (deviation + (bit_rate / 2)) > 500000) { + dev_dbg(&spi->dev, + "set_deviation: illegal input param: %u", deviation); return -EINVAL; } |