From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ABE27C4345F for ; Sat, 20 Apr 2024 13:05:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZZrQY6OFfK6XpERCDCr5gwB8g89tFfsJj+6aJnYkwh4=; b=P1k+gi7PxqKAE8 fZVssoruoTHL1n0cUlv7880v5258259vYe10L2eB2yS8+ot8bODI3VqcdR4h8nJ3F0EvzmMAGJSQK tIyXKBbxsk8Qq4bxs0buflPwC3MT22zk7pYvYL4OFoom5/XlgRqQf4ccPOOrnZfM55/sk2T5e6EMp k0WdNe9zCfqVsC8o+tJyOEu7u01iZVsIecnCKLsBsxwBaXO61zB6BjDEK9C9pxGYxmnfTHjHIptLv /QOVoT3IsBQZO9gXZki+msqdC4+JNq/E4QlEH+nBGvfZULle0D8f2jmeEg6sWjYQK9726l8QKh4Q8 9psLzaj1QbTfAQkq9Zyg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1ryAOd-00000008WLk-2RXE; Sat, 20 Apr 2024 13:04:47 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1ryAOa-00000008WJL-1p6d for linux-arm-kernel@lists.infradead.org; Sat, 20 Apr 2024 13:04:45 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id B153A601D9; Sat, 20 Apr 2024 13:04:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3140C072AA; Sat, 20 Apr 2024 13:04:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1713618273; bh=QamFW/4GCuEWWHNTHqdv7yga8qrR6HqDWk864yMcmsI=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=GvXFrpqTxvJU9pbwvOH+OWJN9vrBF+HIDsJyoxBlEjr7n5b9KRbBQ2gDNNY1hb9so QWSBXudL2KsSBVYN3shgXfLMtqxXDyt3mIRHdAJfOGmH6ME5KUAigMkLGXOwyibBVX k4iMGwES8g/Wyp+Jg29aifJzbysH55a7d0zb5w06fY1QB6v372uYO3ZWi1zz1Sp/yF SZCutEls/IQ+he8fuEawxOG2odfeufK+HFaJQF7GAgFebAot6WfaT9LoMpRtxK+DzH OLaE9pWjWpDQFKD6U6MQDcAmzhdi/zxybx/sapU7mG6UynmQQUEuWSomzjuvvLiVnZ oFSdCRVVkOxgg== Date: Sat, 20 Apr 2024 14:04:17 +0100 From: Jonathan Cameron To: Aren Moynihan Cc: Lars-Peter Clausen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , Liam Girdwood , Mark Brown , Andy Shevchenko , Ondrej Jirman , Uwe =?UTF-8?B?S2xlaW5lLUvDtm5pZw==?= , linux-iio@vger.kernel.org, phone-devel@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev, Willow Barraco Subject: Re: [PATCH 2/4] iio: light: stk3310: Implement vdd supply and power it off during suspend Message-ID: <20240420140417.12b2bf8e@jic23-huawei> In-Reply-To: <20240414175716.958831-2-aren@peacevolution.org> References: <20240414175300.956243-1-aren@peacevolution.org> <20240414175716.958831-1-aren@peacevolution.org> <20240414175716.958831-2-aren@peacevolution.org> X-Mailer: Claws Mail 4.2.0 (GTK 3.24.41; x86_64-pc-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240420_060444_700704_4EF04350 X-CRM114-Status: GOOD ( 27.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, 14 Apr 2024 13:57:14 -0400 Aren Moynihan wrote: > From: Ondrej Jirman > > VDD power input can be used to completely power off the chip during > system suspend. Do so if available. I'd make this non optional (relying on regulator framework providing us a stub for old DT etc) and pay the minor cost of potentially restoring registers when it was never powered down. Simpler code and likely anyone who is doing suspend / resume will have power control anyway. Jonathan > > Signed-off-by: Ondrej Jirman > Signed-off-by: Aren Moynihan > --- > drivers/iio/light/stk3310.c | 56 +++++++++++++++++++++++++++++++++++-- > 1 file changed, 53 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c > index 7b71ad71d78d..bfa090538df7 100644 > --- a/drivers/iio/light/stk3310.c > +++ b/drivers/iio/light/stk3310.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > > #define STK3310_REG_STATE 0x00 > #define STK3310_REG_PSCTRL 0x01 > @@ -117,6 +118,7 @@ struct stk3310_data { > struct regmap_field *reg_int_ps; > struct regmap_field *reg_flag_psint; > struct regmap_field *reg_flag_nf; > + struct regulator *vdd_reg; > }; > > static const struct iio_event_spec stk3310_events[] = { > @@ -607,6 +609,16 @@ static int stk3310_probe(struct i2c_client *client) > > mutex_init(&data->lock); > > + data->vdd_reg = devm_regulator_get_optional(&client->dev, "vdd"); This needs a comment on why it is optional. Generally power supply regulators are not, but I think the point here is to avoid restoring the registers if the chip wasn't powered down? This feels like an interesting gap in the regulator framework. For most cases we can rely on stub / fake regulator being created for always on supplies, but that doesn't let us elide the register writes. My gut feeling is do them unconditionally. Suspend / resume isn't that common that it will matter much. That would allow you to have this as devm_regulator_get() and drop handling of it not being provided. > + if (IS_ERR(data->vdd_reg)) { > + ret = PTR_ERR(data->vdd_reg); > + if (ret == -ENODEV) > + data->vdd_reg = NULL; > + else > + return dev_err_probe(&client->dev, ret, > + "get regulator vdd failed\n"); > + } > + > ret = stk3310_regmap_init(data); > if (ret < 0) > return ret; > @@ -617,9 +629,18 @@ static int stk3310_probe(struct i2c_client *client) > indio_dev->channels = stk3310_channels; > indio_dev->num_channels = ARRAY_SIZE(stk3310_channels); > > + if (data->vdd_reg) { > + ret = regulator_enable(data->vdd_reg); > + if (ret) > + return dev_err_probe(&client->dev, ret, > + "regulator vdd enable failed\n"); > + > + usleep_range(1000, 2000); > + } > + > ret = stk3310_init(indio_dev); > if (ret < 0) > - return ret; > + goto err_vdd_disable; > > if (client->irq > 0) { > ret = devm_request_threaded_irq(&client->dev, client->irq, > @@ -645,32 +666,61 @@ static int stk3310_probe(struct i2c_client *client) > > err_standby: > stk3310_set_state(data, STK3310_STATE_STANDBY); > +err_vdd_disable: > + if (data->vdd_reg) > + regulator_disable(data->vdd_reg); > return ret; > } > > static void stk3310_remove(struct i2c_client *client) > { > struct iio_dev *indio_dev = i2c_get_clientdata(client); > + struct stk3310_data *data = iio_priv(indio_dev); > > iio_device_unregister(indio_dev); > stk3310_set_state(iio_priv(indio_dev), STK3310_STATE_STANDBY); > + if (data->vdd_reg) > + regulator_disable(data->vdd_reg); > } > > static int stk3310_suspend(struct device *dev) > { > struct stk3310_data *data; > + int ret; > > data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > > - return stk3310_set_state(data, STK3310_STATE_STANDBY); > + ret = stk3310_set_state(data, STK3310_STATE_STANDBY); > + if (ret) > + return ret; > + > + if (data->vdd_reg) { As above, I don't think we care enough about overhead on boards where there isn't a vdd regulator. Just do this unconditionally. > + regcache_mark_dirty(data->regmap); > + regulator_disable(data->vdd_reg); > + } > + > + return 0; > } > > static int stk3310_resume(struct device *dev) > { > - u8 state = 0; > struct stk3310_data *data; > + u8 state = 0; > + int ret; > > data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); > + > + if (data->vdd_reg) { > + ret = regulator_enable(data->vdd_reg); > + if (ret) { > + dev_err(dev, "Failed to re-enable regulator vdd\n"); > + return ret; > + } > + > + usleep_range(1000, 2000); > + regcache_sync(data->regmap); > + } > + > if (data->ps_enabled) > state |= STK3310_STATE_EN_PS; > if (data->als_enabled) _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel