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=-18.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B7AE6C4338F for ; Tue, 17 Aug 2021 17:49:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94AA961029 for ; Tue, 17 Aug 2021 17:49:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232060AbhHQRt6 (ORCPT ); Tue, 17 Aug 2021 13:49:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:34178 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230311AbhHQRt5 (ORCPT ); Tue, 17 Aug 2021 13:49:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E756360FD7; Tue, 17 Aug 2021 17:49:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1629222564; bh=SS9Zq8ZnLu+g76roGFuSqAb1eGJnBA/fbxnDtB/qrU8=; h=Subject:To:From:Date:From; b=HPpbPylfi8bwpjkD2T53KiM0svX2LiSjjYXUJM7biRn7TL0AkSPgg81TjTROKzYjy 4n0glQnaK6ZtuVdN9hCrnVg6hjaW1GCHtVB0M99J2GrNZQzlBphIbfZ4fpfmn/kKMN 1i/dlgFAJz27fAL2SZgPIv5tYxFY5JtIOZT/WuxI= Subject: patch "iio: ltc2983: fix device probe" added to staging-testing To: nuno.sa@analog.com, Jonathan.Cameron@huawei.com, Stable@vger.kernel.org, andy.shevchenko@gmail.com, drew@pdp7.com From: Date: Tue, 17 Aug 2021 19:49:08 +0200 Message-ID: <16292225485621@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled iio: ltc2983: fix device probe to my staging git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git in the staging-testing branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will be merged to the staging-next branch sometime soon, after it passes testing, and the merge window is open. If you have any questions about this process, please let me know. >From b76d26d69ecc97ebb24aaf40427a13c808a4f488 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nuno=20S=C3=A1?= Date: Wed, 11 Aug 2021 15:32:20 +0200 Subject: iio: ltc2983: fix device probe MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There is no reason to assume that the IRQ rising edge (indicating that the device start up phase is done) will happen after we request the IRQ. If the device is already up by the time we request it, the call to 'wait_for_completion_timeout()' will timeout and we will fail the device probe even though there's nothing wrong. Fix it by just polling the status register until we get the indication that the device is up and running. As a side effect of this fix, requesting the IRQ is also moved to after the setup function. Fixes: f110f3188e563 ("iio: temperature: Add support for LTC2983") Reported-and-tested-by: Drew Fustini Reviewed-by: Drew Fustini Signed-off-by: Nuno Sá Reviewed-by: Andy Shevchenko Cc: Link: https://lore.kernel.org/r/20210811133220.190264-2-nuno.sa@analog.com Signed-off-by: Jonathan Cameron --- drivers/iio/temperature/ltc2983.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) diff --git a/drivers/iio/temperature/ltc2983.c b/drivers/iio/temperature/ltc2983.c index 3b5ba26d7d86..3b4a0e60e605 100644 --- a/drivers/iio/temperature/ltc2983.c +++ b/drivers/iio/temperature/ltc2983.c @@ -89,6 +89,8 @@ #define LTC2983_STATUS_START_MASK BIT(7) #define LTC2983_STATUS_START(x) FIELD_PREP(LTC2983_STATUS_START_MASK, x) +#define LTC2983_STATUS_UP_MASK GENMASK(7, 6) +#define LTC2983_STATUS_UP(reg) FIELD_GET(LTC2983_STATUS_UP_MASK, reg) #define LTC2983_STATUS_CHAN_SEL_MASK GENMASK(4, 0) #define LTC2983_STATUS_CHAN_SEL(x) \ @@ -1362,17 +1364,16 @@ static int ltc2983_parse_dt(struct ltc2983_data *st) static int ltc2983_setup(struct ltc2983_data *st, bool assign_iio) { - u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0; + u32 iio_chan_t = 0, iio_chan_v = 0, chan, iio_idx = 0, status; int ret; - unsigned long time; - - /* make sure the device is up */ - time = wait_for_completion_timeout(&st->completion, - msecs_to_jiffies(250)); - if (!time) { + /* make sure the device is up: start bit (7) is 0 and done bit (6) is 1 */ + ret = regmap_read_poll_timeout(st->regmap, LTC2983_STATUS_REG, status, + LTC2983_STATUS_UP(status) == 1, 25000, + 25000 * 10); + if (ret) { dev_err(&st->spi->dev, "Device startup timed out\n"); - return -ETIMEDOUT; + return ret; } st->iio_chan = devm_kzalloc(&st->spi->dev, @@ -1492,10 +1493,11 @@ static int ltc2983_probe(struct spi_device *spi) ret = ltc2983_parse_dt(st); if (ret) return ret; - /* - * let's request the irq now so it is used to sync the device - * startup in ltc2983_setup() - */ + + ret = ltc2983_setup(st, true); + if (ret) + return ret; + ret = devm_request_irq(&spi->dev, spi->irq, ltc2983_irq_handler, IRQF_TRIGGER_RISING, name, st); if (ret) { @@ -1503,10 +1505,6 @@ static int ltc2983_probe(struct spi_device *spi) return ret; } - ret = ltc2983_setup(st, true); - if (ret) - return ret; - indio_dev->name = name; indio_dev->num_channels = st->iio_channels; indio_dev->channels = st->iio_chan; -- 2.32.0