On Mon, 2020-08-31 at 19:06 -0300, Santiago Hormazabal wrote: > This chip requires almost no support components and can used over I2C. > The driver uses the I2C bus and exposes the controls as a V4L2 radio. > Tested with a module that contains this chip (from SZZSJDZ.com, > part number ZJ-801B, even tho the company seems defunct now), and an H2+ > AllWinner SoC running a kernel built off 07d999f of the media_tree. Thanks. style trivia: [] > diff --git a/drivers/media/radio/radio-kt0913.c b/drivers/media/radio/radio-kt0913.c [] > +static const struct reg_sequence kt0913_init_regs_to_defaults[] = { > + /* Standby disabled, volume 0dB */ > + { KT0913_REG_RXCFG, 0x881f }, These might be more legible on single lines, ignoring the 80 column limits. > + /* FM Channel spacing = 50kHz, Right & Left unmuted */ > + { KT0913_REG_SEEK, 0x000b }, etc... [] > +static int __kt0913_set_fm_frequency(struct kt0913_device *radio, > + unsigned int frequency) > +{ > + return regmap_write(radio->regmap, KT0913_REG_TUNE, > + KT0913_TUNE_FMTUNE_ON | (frequency / KT0913_FMCHAN_MUL)); It might be nicer to align multi-line statements to the open parenthesis. [] > +static int __kt0913_set_au_gain(struct kt0913_device *radio, s32 gain) > +{ > + switch (gain) { > + case 6: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_6DB); > + case 3: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_3DB); > + case 0: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_0DB); > + case -3: > + return regmap_update_bits(radio->regmap, > + KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, > + KT0913_AMSYSCFG_AU_GAIN_MIN_3DB); > + default: > + return -EINVAL; > + } > +} It's generally more legible to write this with an intermediate variable holding the changed value. It's also most commonly smaller object code. static int __kt0913_set_au_gain(struct kt0913_device *radio, s32 gain) { int val; switch (gain) { case 6: val = KT0913_AMSYSCFG_AU_GAIN_6DB; break; case 3: val = KT0913_AMSYSCFG_AU_GAIN_3DB; break; case 0: val = KT0913_AMSYSCFG_AU_GAIN_0DB; break; case -3: val = KT0913_AMSYSCFG_AU_GAIN_MIN_3DB; break; default: return -EINVAL; } return regmap_update_bits(radio->regmap, KT0913_REG_AMSYSCFG, KT0913_AMSYSCFG_AU_GAIN_MASK, val); }