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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CE77C43613 for ; Sat, 22 Jun 2019 10:18:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1051C206B7 for ; Sat, 22 Jun 2019 10:18:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561198714; bh=X8hyEcMmcXqPuo+a/NbwR1P2ZlES7nFnwsZGCafU0jU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=Kmpf0U/eAvnX+WY4Rf35qAwl1HZcpv1a60xeln4yJ5VNXh494cI84DCaLMvi6JjDZ zpNTRzIwW/295Soh+rQd35QEOiPkzs/i2lYykPI6xTbzkEXidIJilksr/2+702PppP yntLUWRuJd2QSM++JTWXgmvbspXv4LwnvYz9TEoU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726121AbfFVKSd (ORCPT ); Sat, 22 Jun 2019 06:18:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:38734 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726130AbfFVKSd (ORCPT ); Sat, 22 Jun 2019 06:18:33 -0400 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DAACE20665; Sat, 22 Jun 2019 10:18:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561198712; bh=X8hyEcMmcXqPuo+a/NbwR1P2ZlES7nFnwsZGCafU0jU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ei/trMngktPgLnGPEyEvSJ9jeDMankudhU6zw2ZKrmfDLilhfRMmpfcA8xNXyyVaK ehC0wODbTNnit4Buu1rT9X4799Ys0HnMTuQs5dpHTOcn4taW6KZmwxeuAicYxysayQ tlsa3tcDsGEhdsHbZ1hnNPWsoui2ApKD/nBfmB5w= Date: Sat, 22 Jun 2019 11:18:27 +0100 From: Jonathan Cameron To: Fabien Lahoudere Cc: kernel@collabora.com, Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 7/8] iio: common: cros_ec_sensors: add sysfs attribute for frequencies Message-ID: <20190622111827.54ebe9a9@archlinux> In-Reply-To: References: X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Tue, 18 Jun 2019 11:06:38 +0200 Fabien Lahoudere wrote: > Embedded controller return minimum and maximum frequencies, unfortunately > we have no way to know the step for all available frequencies. > Even if not complete, we can return a list of known values using the > standard read_avail callback (IIO_CHAN_INFO_SAMP_FREQ) to provide them to > userland. > > Now cros_ec_* sensors provides frequencies values in sysfs like this: > "0 min max". > > 0 is always true to disable the sensor. Hmm. 0 frequency feels like a kind of non standard use of the ABI. I suppose it's fairly logical and it does no harm if userspace never uses it so I guess we can let this use in without updating the docs. I'd like some feedback from the chromeos side on whether this is a sensible way of representing things? Note that generic userspace will only pick one of those values, it won't magically decide to go for somewhere inbetween. Jonathan > > Signed-off-by: Fabien Lahoudere > --- > .../cros_ec_sensors/cros_ec_sensors_core.c | 22 +++++++++++++++++++ > .../linux/iio/common/cros_ec_sensors_core.h | 4 +++- > 2 files changed, 25 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > index 2ce077b576a4..8df82b675752 100644 > --- a/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > +++ b/drivers/iio/common/cros_ec_sensors/cros_ec_sensors_core.c > @@ -10,6 +10,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -86,6 +87,26 @@ static int cros_ec_get_host_cmd_version_mask(struct cros_ec_device *ec_dev, > return ret; > } > > +static int cros_ec_read_avail(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, > + const int **vals, > + int *type, > + int *length, > + long mask) > +{ > + struct cros_ec_sensors_core_state *state = iio_priv(indio_dev); > + > + switch (mask) { > + case IIO_CHAN_INFO_SAMP_FREQ: > + *length = 3; > + *vals = (const int *)&state->frequency_range; > + *type = IIO_VAL_INT; > + return IIO_AVAIL_LIST; > + } > + > + return -EINVAL; > +} > + > int cros_ec_sensors_core_init(struct platform_device *pdev, > int num_channels, > bool physical_device) > @@ -161,6 +182,7 @@ int cros_ec_sensors_core_init(struct platform_device *pdev, > } > } > > + state->info.read_avail = cros_ec_read_avail; > indio_dev->info = &state->info; > > /* Timestamp channel */ > diff --git a/include/linux/iio/common/cros_ec_sensors_core.h b/include/linux/iio/common/cros_ec_sensors_core.h > index 89937ad242ef..5fa9ba5332e0 100644 > --- a/include/linux/iio/common/cros_ec_sensors_core.h > +++ b/include/linux/iio/common/cros_ec_sensors_core.h > @@ -140,7 +140,9 @@ int cros_ec_sensors_core_register(struct platform_device *pdev, > channel[idx].scan_type.shift = 0;\ > channel[idx].scan_index = idx;\ > channel[idx].ext_info = cros_ec_sensors_ext_info;\ > - channel[idx].scan_type.sign = 'u'; > + channel[idx].scan_type.sign = 'u';\ > + channel[idx].info_mask_shared_by_all_available = \ > + BIT(IIO_CHAN_INFO_SAMP_FREQ); > > /** > * cros_ec_motion_send_host_cmd() - send motion sense host command