From: Kevin Cernekee <cernekee@chromium.org> To: Mark Brown <broonie@kernel.org> Cc: lgirdwood@gmail.com, dgreid@chromium.org, Andrew Bresticker <abrestic@chromium.org>, Olof Johansson <olofj@chromium.org>, alsa-devel@alsa-project.org, devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org> Subject: Re: [PATCH 2/3] ASoC: tas571x: New driver for TI TAS571x power amplifiers Date: Sat, 18 Apr 2015 09:16:36 -0700 [thread overview] Message-ID: <CAJzqFtYVd+jHesoNnG47ftoK9SWYUmXwDXpf2==s3Rv1ewpsYg@mail.gmail.com> (raw) In-Reply-To: <20150418113632.GE26185@sirena.org.uk> On Sat, Apr 18, 2015 at 4:36 AM, Mark Brown <broonie@kernel.org> wrote: > On Wed, Apr 15, 2015 at 02:42:20PM -0700, Kevin Cernekee wrote: >> +static int tas571x_set_sysclk(struct snd_soc_dai *dai, >> + int clk_id, unsigned int freq, int dir) >> +{ >> + /* >> + * TAS5717 datasheet pg 21: "The DAP can autodetect and set the >> + * internal clock-control logic to the appropriate settings for all >> + * supported clock rates as defined in the clock control register." >> + */ >> + return 0; >> +} > > Remove empty functions, at best they waste space at worst they break > things. Without the empty function, we run into problems with drivers that abort when they get -ENOTSUPP here: sound/soc/atmel/atmel_wm8904.c: ret = snd_soc_dai_set_sysclk(codec_dai, WM8904_CLK_FLL, sound/soc/atmel/atmel_wm8904.c- 0, SND_SOC_CLOCK_IN); sound/soc/atmel/atmel_wm8904.c- if (ret < 0) { sound/soc/atmel/atmel_wm8904.c- pr_err("%s -failed to set wm8904 SYSCLK\n", __func__); sound/soc/atmel/atmel_wm8904.c- return ret; sound/soc/atmel/atmel_wm8904.c- } Is there a stub version that I can use instead? Nothing jumped out at me when looking at the other codec drivers. >> +static int tas571x_set_shutdown(struct tas571x_private *priv, bool is_shutdown) >> +{ >> + return regmap_update_bits(priv->regmap, TAS571X_SYS_CTRL_2_REG, >> + TAS571X_SYS_CTRL_2_SDN_MASK, >> + is_shutdown ? TAS571X_SYS_CTRL_2_SDN_MASK : 0); >> +} > >> + ret = tas571x_set_shutdown(priv, false); >> + if (ret) >> + return ret; >> + break; >> + case SND_SOC_BIAS_STANDBY: >> + ret = tas571x_set_shutdown(priv, true); >> + if (ret) >> + return ret; > > This looks like it'd be clearer just as direct register updates, I'm not > sure a function to set a single bit is addinng much. It might be useful if another tas571x variant put the bit somewhere else, but that hasn't happened yet so I can nuke the helper function for now. >> + case SND_SOC_BIAS_OFF: >> + /* Note that this kills I2C accesses. */ >> + assert_pdn = 1; > > No, the GPIO set associated with it kills I2C access. I'd also expect > to see the regmap being marked cache only before we do this and a resync > of the register map when we power back up (assuming that is actually a > power down). Hmm, not sure if this actually resets the registers back to power-on defaults, but I'll check. >> + /* >> + * The master volume defaults to 0x3ff (mute), but we ignore >> + * (zero) the LSB because the hardware step size is 0.125 dB >> + * and TLV_DB_SCALE_ITEM has a resolution of 0.01 dB. >> + */ >> + if (regmap_write(priv->regmap, TAS571X_MVOL_REG, 0x3fe)) >> + return -EIO; > > I don't understand this - is the LSB a mute bit or sommething? The 10-bit master volume field on 5717/5719 works like: 0x3ff: MUTE (power-on default) 0x3fe: -103.750 dB 0x3fd: -103.625 dB [lots more options, in 0.125 dB increments] 0x001: 23.875 dB 0x000: 24.000 dB Since we only have a resolution of 0.01 dB, the driver forces the LSB to 0 and uses 0.25 dB increments instead of 0.125 dB. Mute is handled through the dedicated per-channel soft mute register bits instead of the 0x3ff volume setting.
WARNING: multiple messages have this Message-ID (diff)
From: Kevin Cernekee <cernekee-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org> To: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Cc: lgirdwood-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, dgreid-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, Andrew Bresticker <abrestic-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, Olof Johansson <olofj-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>, alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" <linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org> Subject: Re: [PATCH 2/3] ASoC: tas571x: New driver for TI TAS571x power amplifiers Date: Sat, 18 Apr 2015 09:16:36 -0700 [thread overview] Message-ID: <CAJzqFtYVd+jHesoNnG47ftoK9SWYUmXwDXpf2==s3Rv1ewpsYg@mail.gmail.com> (raw) In-Reply-To: <20150418113632.GE26185-GFdadSzt00ze9xe1eoZjHA@public.gmane.org> On Sat, Apr 18, 2015 at 4:36 AM, Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote: > On Wed, Apr 15, 2015 at 02:42:20PM -0700, Kevin Cernekee wrote: >> +static int tas571x_set_sysclk(struct snd_soc_dai *dai, >> + int clk_id, unsigned int freq, int dir) >> +{ >> + /* >> + * TAS5717 datasheet pg 21: "The DAP can autodetect and set the >> + * internal clock-control logic to the appropriate settings for all >> + * supported clock rates as defined in the clock control register." >> + */ >> + return 0; >> +} > > Remove empty functions, at best they waste space at worst they break > things. Without the empty function, we run into problems with drivers that abort when they get -ENOTSUPP here: sound/soc/atmel/atmel_wm8904.c: ret = snd_soc_dai_set_sysclk(codec_dai, WM8904_CLK_FLL, sound/soc/atmel/atmel_wm8904.c- 0, SND_SOC_CLOCK_IN); sound/soc/atmel/atmel_wm8904.c- if (ret < 0) { sound/soc/atmel/atmel_wm8904.c- pr_err("%s -failed to set wm8904 SYSCLK\n", __func__); sound/soc/atmel/atmel_wm8904.c- return ret; sound/soc/atmel/atmel_wm8904.c- } Is there a stub version that I can use instead? Nothing jumped out at me when looking at the other codec drivers. >> +static int tas571x_set_shutdown(struct tas571x_private *priv, bool is_shutdown) >> +{ >> + return regmap_update_bits(priv->regmap, TAS571X_SYS_CTRL_2_REG, >> + TAS571X_SYS_CTRL_2_SDN_MASK, >> + is_shutdown ? TAS571X_SYS_CTRL_2_SDN_MASK : 0); >> +} > >> + ret = tas571x_set_shutdown(priv, false); >> + if (ret) >> + return ret; >> + break; >> + case SND_SOC_BIAS_STANDBY: >> + ret = tas571x_set_shutdown(priv, true); >> + if (ret) >> + return ret; > > This looks like it'd be clearer just as direct register updates, I'm not > sure a function to set a single bit is addinng much. It might be useful if another tas571x variant put the bit somewhere else, but that hasn't happened yet so I can nuke the helper function for now. >> + case SND_SOC_BIAS_OFF: >> + /* Note that this kills I2C accesses. */ >> + assert_pdn = 1; > > No, the GPIO set associated with it kills I2C access. I'd also expect > to see the regmap being marked cache only before we do this and a resync > of the register map when we power back up (assuming that is actually a > power down). Hmm, not sure if this actually resets the registers back to power-on defaults, but I'll check. >> + /* >> + * The master volume defaults to 0x3ff (mute), but we ignore >> + * (zero) the LSB because the hardware step size is 0.125 dB >> + * and TLV_DB_SCALE_ITEM has a resolution of 0.01 dB. >> + */ >> + if (regmap_write(priv->regmap, TAS571X_MVOL_REG, 0x3fe)) >> + return -EIO; > > I don't understand this - is the LSB a mute bit or sommething? The 10-bit master volume field on 5717/5719 works like: 0x3ff: MUTE (power-on default) 0x3fe: -103.750 dB 0x3fd: -103.625 dB [lots more options, in 0.125 dB increments] 0x001: 23.875 dB 0x000: 24.000 dB Since we only have a resolution of 0.01 dB, the driver forces the LSB to 0 and uses 0.25 dB increments instead of 0.125 dB. Mute is handled through the dedicated per-channel soft mute register bits instead of the 0x3ff volume setting. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2015-04-18 16:17 UTC|newest] Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-04-15 21:42 [PATCH 1/3] ASoC: tas571x: Add DT binding document Kevin Cernekee 2015-04-15 21:42 ` Kevin Cernekee 2015-04-15 21:42 ` [PATCH 2/3] ASoC: tas571x: New driver for TI TAS571x power amplifiers Kevin Cernekee 2015-04-16 12:57 ` [alsa-devel] " Lars-Peter Clausen 2015-04-16 12:57 ` Lars-Peter Clausen 2015-04-18 11:39 ` Mark Brown 2015-04-18 11:39 ` Mark Brown 2015-04-20 20:56 ` Kevin Cernekee 2015-04-20 21:14 ` Mark Brown 2015-04-18 11:36 ` Mark Brown 2015-04-18 16:16 ` Kevin Cernekee [this message] 2015-04-18 16:16 ` Kevin Cernekee 2015-04-18 17:11 ` Mark Brown 2015-04-18 20:07 ` Kevin Cernekee 2015-04-20 12:21 ` Mark Brown 2015-04-20 12:21 ` Mark Brown 2015-04-20 15:12 ` Kevin Cernekee 2015-04-20 15:12 ` Kevin Cernekee 2015-04-20 16:05 ` Andrew Bresticker 2015-04-20 20:14 ` Mark Brown 2015-04-20 20:14 ` Mark Brown 2015-04-24 0:47 ` Kevin Cernekee 2015-04-24 0:47 ` Kevin Cernekee 2015-04-24 9:28 ` Mark Brown 2015-04-24 13:52 ` Kevin Cernekee 2015-04-24 16:50 ` Mark Brown 2015-04-15 21:42 ` [PATCH 3/3] MAINTAINERS: Add entry for tas571x ASoC codec driver Kevin Cernekee 2015-04-15 21:42 ` Kevin Cernekee 2015-04-18 11:16 ` [PATCH 1/3] ASoC: tas571x: Add DT binding document Mark Brown 2015-04-20 21:16 ` Kevin Cernekee 2015-04-20 21:16 ` Kevin Cernekee 2015-04-20 21:18 ` Kevin Cernekee 2015-04-20 22:03 ` Mark Brown 2015-04-20 22:48 ` Kevin Cernekee 2015-04-21 16:45 ` Mark Brown 2015-04-21 16:45 ` Mark Brown
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to='CAJzqFtYVd+jHesoNnG47ftoK9SWYUmXwDXpf2==s3Rv1ewpsYg@mail.gmail.com' \ --to=cernekee@chromium.org \ --cc=abrestic@chromium.org \ --cc=alsa-devel@alsa-project.org \ --cc=broonie@kernel.org \ --cc=devicetree@vger.kernel.org \ --cc=dgreid@chromium.org \ --cc=lgirdwood@gmail.com \ --cc=linux-kernel@vger.kernel.org \ --cc=olofj@chromium.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.