On Tue, Jul 30, 2019 at 01:09:36PM +0100, Thomas Preston wrote: > Add an I2C based codec driver for ST TDA7802 amplifier. The amplifier > supports 4 audio channels but can support up to 16 with multiple > devices. > > Signed-off-by: Thomas Preston <thomas.preston@xxxxxxxxxxxxxxx> > Cc: Patrick Glaser <pglaser@xxxxxxxxx> > Cc: Rob Duncan <rduncan@xxxxxxxxx> > Cc: Nate Case <ncase@xxxxxxxxx> > --- > Changes since v1: > - Use ALSA kcontrol interface to expose device controls to userland > - Gain > - Channel diagnostic mode > - Impedance efficiency optimiser. I decided against setting this > as a DT property since it seems like something that can be > changed on the fly. > - Add regmap default values > - Channel unmute by default is added in a downstream patch. > - I'm not sure if I should keep this since they're all zero, > although there are other drivers will all-zero reg_defaults. > - I believe the "//" style is used for SPDX headers in normal C source files. > https://lwn.net/Articles/739183/ > - Drop the "enable" sysfs device attribute. > - Don't set TDM format using magic numbers. > - Set sample rate using hw_params. > - Remove unecessary defines. > - Use DAPM to handle AMP_ON. > - Cosmetic fixups > > sound/soc/codecs/Kconfig | 6 + > sound/soc/codecs/Makefile | 2 + > sound/soc/codecs/tda7802.c | 509 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 517 insertions(+) > create mode 100644 sound/soc/codecs/tda7802.c > > +++ b/sound/soc/codecs/tda7802.c > @@ -0,0 +1,509 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * tda7802.c -- codec driver for ST TDA7802 > + * > + * Copyright (C) 2016-2019 Tesla Motors, Inc. > + */ Better to make the whole comment // see something like sound/soc/codecs/cs47l35.c for an example. > +static int tda7802_set_bias_level(struct snd_soc_component *component, > + enum snd_soc_bias_level level) > +{ > + const struct tda7802_priv *tda7802 = > + snd_soc_component_get_drvdata(component); > + struct snd_soc_dapm_context *dapm_context = > + snd_soc_component_get_dapm(component); > + const enum snd_soc_bias_level oldlevel = > + snd_soc_dapm_get_bias_level(dapm_context); > + int err = 0; > + > + dev_dbg(component->dev, "%s level %d\n", __func__, level); > + > + switch (level) { > + case SND_SOC_BIAS_ON: > + break; > + case SND_SOC_BIAS_PREPARE: > + break; > + case SND_SOC_BIAS_STANDBY: > + err = regulator_enable(tda7802->enable_reg); > + if (err < 0) { > + dev_err(component->dev, "Could not enable.\n"); > + return err; > + } > + dev_dbg(component->dev, "Regulator enabled\n"); > + msleep(ENABLE_DELAY_MS); > + > + if (oldlevel == SND_SOC_BIAS_OFF) { > + dev_dbg(component->dev, "Syncing regcache\n"); > + err = regcache_sync(component->regmap); > + if (err < 0) > + dev_err(component->dev, > + "Could not sync regcache, %d\n", err); If your doing a regcache_sync I would probably have expected to see calls to regcache_cache_only. If the device needs syncing that implies the hardware registers have lost state, so there is little point in writing to them if they are unavailable/about to loose their state. > + } > + break; > + case SND_SOC_BIAS_OFF: > + regcache_mark_dirty(component->regmap); > + err = regulator_disable(tda7802->enable_reg); > + if (err < 0) > + dev_err(component->dev, "Could not disable.\n"); > + break; > + } > + > + return err; > +} Thanks, Charles
