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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 B8667C433ED for ; Fri, 23 Apr 2021 16:07:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7DA6261163 for ; Fri, 23 Apr 2021 16:07:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232024AbhDWQHb (ORCPT ); Fri, 23 Apr 2021 12:07:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229691AbhDWQH3 (ORCPT ); Fri, 23 Apr 2021 12:07:29 -0400 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23157C061574; Fri, 23 Apr 2021 09:06:52 -0700 (PDT) Received: by mail-pj1-x1034.google.com with SMTP id g1-20020a17090adac1b0290150d07f9402so1422485pjx.5; Fri, 23 Apr 2021 09:06:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=IogqCPyvEvuM6GWvpXpHl19+M+Wj9F934eJ8mKManQw=; b=k2KvuTXUaJRxSWSbxOHfmPWor1BH2QRGJTkOflXnvKePtPb2rFZVAnV+MN3p4+VBYe zqL//K4qzi9xpVeQ27cexC+jwQ/ch6vrLSOfCy+5068m/S7jQ/IIBy3F7XHM89stpaQC 5yJgpQs4Mnr1aEsnzaPEtQ+9jQe/OwsvpEY6Ixpxwro+3+0ouzUJJ0iSK5E6348mTBUX VF0LYVKjKY2kxfKpNz0rpjIBGUlLpNDH0nUU4eyxUQVyHAex+/tzHtMY0JJyywMJZbmI q9ZMPZIuenE05lKaPeFwyWP+K0Z0oGZjIk1DkSAy1d8b4eZIAkCPxdStzMDoGFREKBA8 6Nig== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=IogqCPyvEvuM6GWvpXpHl19+M+Wj9F934eJ8mKManQw=; b=g3HF3dGunErDdOgt/deLUe4+fZybL+7VlA0onvRXnrIly0hJhiYyLkIGWceVP6gN/V AFmZw3oTONGf02Fdw6bOadoz8SRAWAEaH1/kb7H37eHVzZxGiILaCGs8fF2d8ownsq+p i0UV0BdU/G0e+lTH2UPBK8yDCLND+cX4jG35p2rTAH3tlxDEYrph4ULQmrHh0bGt0XxI uZ5hAG5K1aAoqgpNEdFDvz3xpLIaAur0gBnfW+oQpJBrieMIXCuWo4Lt9hgde8XfrCRt 437gPpoya+DBOSKkDhCqM3XatReKguPSnmFXaJOHUKABuBJZZNZzFfO7TTfcR/AAyl0K K9ag== X-Gm-Message-State: AOAM533CzlOwDzKXuchMp9C51Mx6UFj9BY9Qhu8yM6C8CuPyXdgfZC+D w7wskyzU5CYaBvueNZ4EcsKjYD4TOY02UudxNJ0= X-Google-Smtp-Source: ABdhPJyCF5pfkqJvfI/SycPE59PP6Rrzx1x/SiXt/11eiyE8YcxxM3KPBfePw+OrmXFGq3h+2xVTOOJevU9KJV3Hpic= X-Received: by 2002:a17:90a:bd13:: with SMTP id y19mr6859715pjr.181.1619194006820; Fri, 23 Apr 2021 09:06:46 -0700 (PDT) MIME-Version: 1.0 References: <20210420132333.99886-1-tomas.melin@vaisala.com> <20210420132333.99886-3-tomas.melin@vaisala.com> In-Reply-To: <20210420132333.99886-3-tomas.melin@vaisala.com> From: Andy Shevchenko Date: Fri, 23 Apr 2021 19:06:30 +0300 Message-ID: Subject: Re: [PATCH v4 2/2] iio: accel: Add driver for Murata SCA3300 accelerometer To: Tomas Melin Cc: Jonathan Cameron , devicetree , linux-iio , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 20, 2021 at 4:24 PM Tomas Melin wrote: > > Add initial support for Murata SCA3300 3-axis industrial > accelerometer with digital SPI interface. This device also > provides a temperature measurement. Thanks for an update, my comments below. They can be addressed as followups, but I think regmap API can be considered right now. ... > +static int sca3300_read_reg(struct sca3300_data *sca_data, u8 reg, int *val) > +{ > + int ret; > + > + mutex_lock(&sca_data->lock); > + sca_data->txbuf[0] = reg << 2; > + ret = sca3300_transfer(sca_data, val); > + mutex_unlock(&sca_data->lock); > + if (ret != -EINVAL) > + return ret; > + > + return sca3300_error_handler(sca_data); > +} > + > +static int sca3300_write_reg(struct sca3300_data *sca_data, u8 reg, int val) > +{ > + int reg_val = 0; > + int ret; > + > + mutex_lock(&sca_data->lock); > + /* BIT(7) for write operation */ > + sca_data->txbuf[0] = BIT(7) | (reg << 2); > + put_unaligned_be16(val, &sca_data->txbuf[1]); > + ret = sca3300_transfer(sca_data, ®_val); > + mutex_unlock(&sca_data->lock); > + if (ret != -EINVAL) > + return ret; > + > + return sca3300_error_handler(sca_data); > +} Okay, BIT(7) for write/read is pretty much standard stuff for such sensors. If you transform your driver to use REGMAP_SPI, you will get it thru regmap configuration. Also, you will get a locking there, in case you don't need to have several I/O in a row atomically. .. > + for_each_set_bit(bit, indio_dev->active_scan_mask, > + indio_dev->masklength) { One line? > + ret = sca3300_read_reg(data, sca3300_channels[bit].address, > + &val); > + if (ret) { > + dev_err_ratelimited(&data->spi->dev, > + "failed to read register, error: %d\n", ret); > + /* handled, but bailing out due to errors */ > + goto out; > + } > + data->scan.channels[i++] = val; > + } ... > + int ret; > + int value = 0; Reversed xmas tree ordering? ... > + /* > + * Wait 1ms after SW-reset command. > + * Wait 15ms for settling of signal paths. > + */ > + usleep_range(16e3, 50e3); Hmm... Perhaps re-use msleep_range() https://elixir.bootlin.com/linux/latest/source/drivers/media/i2c/imx274.c#L601? ... > + .debugfs_reg_access = &sca3300_debugfs_reg_access, Reading of the registers you will get as a bonus when switching over to regmap SPI API. -- With Best Regards, Andy Shevchenko