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=-18.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=unavailable 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 188F1C56202 for ; Tue, 17 Nov 2020 16:02:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ABC462468E for ; Tue, 17 Nov 2020 16:02:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726949AbgKQQCf convert rfc822-to-8bit (ORCPT ); Tue, 17 Nov 2020 11:02:35 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:2123 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726803AbgKQQCe (ORCPT ); Tue, 17 Nov 2020 11:02:34 -0500 Received: from fraeml736-chm.china.huawei.com (unknown [172.18.147.207]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Cb9dy45Ndz67FMm; Wed, 18 Nov 2020 00:00:54 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml736-chm.china.huawei.com (10.206.15.217) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Tue, 17 Nov 2020 17:02:27 +0100 Received: from localhost (10.47.31.177) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1913.5; Tue, 17 Nov 2020 16:02:27 +0000 Date: Tue, 17 Nov 2020 16:02:18 +0000 From: Jonathan Cameron To: Alexandru Ardelean CC: Alexandru Ardelean , linux-iio , , LKML , Jonathan Cameron , "Rob Herring" , Vaishnav M A , "Andy Shevchenko" Subject: Re: [PATCH 2/3] iio: adc: ad7887: convert driver to full DT probing Message-ID: <20201117160218.0000274b@Huawei.com> In-Reply-To: References: <20201117075254.4861-1-alexandru.ardelean@analog.com> <20201117075254.4861-2-alexandru.ardelean@analog.com> <20201117110111.0000468a@Huawei.com> <20201117110447.0000393c@Huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT X-Originating-IP: [10.47.31.177] X-ClientProxiedBy: lhreml736-chm.china.huawei.com (10.201.108.87) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 17 Nov 2020 17:03:06 +0200 Alexandru Ardelean wrote: > On Tue, Nov 17, 2020 at 1:06 PM Jonathan Cameron > wrote: > > > > On Tue, 17 Nov 2020 11:01:11 +0000 > > Jonathan Cameron wrote: > > > > > On Tue, 17 Nov 2020 09:52:53 +0200 > > > Alexandru Ardelean wrote: > > > > > > > This change removes the SPI device table, adds an OF device table instead. > > > > This should also be usable for ACPI via PRP0001. > > > > > > > > This device is usually probed via device-tree, so it makes more sense to > > > > use the OF device table. > > > > > > > > Signed-off-by: Alexandru Ardelean > > > So, we've had a few cases of having to put the device_id table > > > back again recently. > > > https://lore.kernel.org/linux-iio/20201101152613.2c37581a@archlinux/ > > > > > > They tend to be due to greybus doing it's probing in yet another fashion. > > > So far they've been all i2c devices, but I kind of assume it does the same for spi. > > > https://elixir.bootlin.com/linux/latest/source/drivers/staging/greybus/spilib.c#L437 > > > > > > How device_get_match_data() plays with that I'm not sure. It probably > > > doesn't right now given swnode doesn't have a device_get_match_data() callback. > > > > > > https://elixir.bootlin.com/linux/latest/source/drivers/base/swnode.c#L539 > > > > > > So after all that I think I've argued myself around to thinking what you have > > > here is fine. If someone wants to support this via a swnode then they can > > > figure out how to make that work. > > > > > > +CC Vaishnav and Andy for their input. > > > > > > Otherwise looks fine to me. > > > > Having said that.... Why are we going through this dance for driver with > > only one compatible? Are there other parts on their way? > > If not, perhaps we should just rip out the matching code entirely in > > the interests of simplicity. > > So, this one has a bit of a funny story. > There's an AD7888 which is similar in terms of registers but with more channels. > Lars did a patch to support it on top of AD7887: > https://github.com/analogdevicesinc/linux/commits/iio-ad7888 > > We tried to order a part for this to test the changes, but we got a > reply that it's obsolete. > The website says it is still in production. > So, I was confused about the answer we got. ¯\_(ツ)_/¯ > > In the meantime, I thought I'd take some of the cleanup value of Lars' > work and do the cleanup only. > We may still find that part somewhere and maybe add it, or maybe > another one would come along. > I don't know at this point. I'm mostly looking at some of my backlog > stuff and trying to cleanup old stuff. > > I'm fine to simplify the driver now and add the matching bits later. Sounds good to me. > > > > > Jonathan > > > > > > > > Thanks, > > > > > > Jonathan > > > > > > > > > > --- > > > > drivers/iio/adc/ad7887.c | 23 +++++++++++++++-------- > > > > 1 file changed, 15 insertions(+), 8 deletions(-) > > > > > > > > diff --git a/drivers/iio/adc/ad7887.c b/drivers/iio/adc/ad7887.c > > > > index 06f684c053a0..4f68a1b17ec8 100644 > > > > --- a/drivers/iio/adc/ad7887.c > > > > +++ b/drivers/iio/adc/ad7887.c > > > > @@ -40,6 +40,7 @@ enum ad7887_channels { > > > > > > > > /** > > > > * struct ad7887_chip_info - chip specifc information > > > > + * @name: the name of the part > > > > * @int_vref_mv: the internal reference voltage > > > > * @channels: channels specification > > > > * @num_channels: number of channels > > > > @@ -47,6 +48,7 @@ enum ad7887_channels { > > > > * @num_dual_channels: number of channels in dual mode > > > > */ > > > > struct ad7887_chip_info { > > > > + const char *name; > > > > u16 int_vref_mv; > > > > const struct iio_chan_spec *channels; > > > > unsigned int num_channels; > > > > @@ -218,6 +220,7 @@ static const struct ad7887_chip_info ad7887_chip_info_tbl[] = { > > > > * More devices added in future > > > > */ > > > > [ID_AD7887] = { > > > > + .name = "ad7887", > > > > .channels = ad7887_channels, > > > > .num_channels = ARRAY_SIZE(ad7887_channels), > > > > .dual_channels = ad7887_dual_channels, > > > > @@ -239,12 +242,17 @@ static void ad7887_reg_disable(void *data) > > > > > > > > static int ad7887_probe(struct spi_device *spi) > > > > { > > > > + const struct ad7887_chip_info *info; > > > > struct ad7887_state *st; > > > > struct iio_dev *indio_dev; > > > > bool dual_mode; > > > > uint8_t mode; > > > > int ret; > > > > > > > > + info = device_get_match_data(&spi->dev); > > > > + if (!info) > > > > + return -ENODEV; > > > > + > > > > indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); > > > > if (indio_dev == NULL) > > > > return -ENOMEM; > > > > @@ -269,13 +277,12 @@ static int ad7887_probe(struct spi_device *spi) > > > > return ret; > > > > } > > > > > > > > - st->chip_info = > > > > - &ad7887_chip_info_tbl[spi_get_device_id(spi)->driver_data]; > > > > + st->chip_info = info; > > > > > > > > spi_set_drvdata(spi, indio_dev); > > > > st->spi = spi; > > > > > > > > - indio_dev->name = spi_get_device_id(spi)->name; > > > > + indio_dev->name = st->chip_info->name; > > > > indio_dev->info = &ad7887_info; > > > > indio_dev->modes = INDIO_DIRECT_MODE; > > > > > > > > @@ -336,18 +343,18 @@ static int ad7887_probe(struct spi_device *spi) > > > > return devm_iio_device_register(&spi->dev, indio_dev); > > > > } > > > > > > > > -static const struct spi_device_id ad7887_id[] = { > > > > - {"ad7887", ID_AD7887}, > > > > - {} > > > > +static const struct of_device_id ad7887_of_match[] = { > > > > + { .compatible = "adi,ad7887", .data = &ad7887_chip_info_tbl[ID_AD7887] }, > > > > + { } > > > > }; > > > > -MODULE_DEVICE_TABLE(spi, ad7887_id); > > > > +MODULE_DEVICE_TABLE(of, ad7887_of_match); > > > > > > > > static struct spi_driver ad7887_driver = { > > > > .driver = { > > > > .name = "ad7887", > > > > + .of_match_table = ad7887_of_match, > > > > }, > > > > .probe = ad7887_probe, > > > > - .id_table = ad7887_id, > > > > }; > > > > module_spi_driver(ad7887_driver); > > > > > > > > >