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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, 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 37BE5C04AAF for ; Thu, 16 May 2019 18:02:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 040EB20657 for ; Thu, 16 May 2019 18:02:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728991AbfEPSCJ (ORCPT ); Thu, 16 May 2019 14:02:09 -0400 Received: from foss.arm.com ([217.140.101.70]:53688 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726520AbfEPSCJ (ORCPT ); Thu, 16 May 2019 14:02:09 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 340FA19BF; Thu, 16 May 2019 11:02:09 -0700 (PDT) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 692343F5AF; Thu, 16 May 2019 11:02:07 -0700 (PDT) Subject: Re: [PATCH v2] gnss: get serial speed from subdrivers To: Loys Ollivier , Johan Hovold , Matthias Brugger Cc: baylibre-upstreaming@groups.io, linux-kernel@vger.kernel.org, Corentin Labbe , linux-mediatek@lists.infradead.org, Colin Ian King , linux-arm-kernel@lists.infradead.org References: <1558024626-19395-1-git-send-email-lollivier@baylibre.com> From: Robin Murphy Message-ID: <69b5e90c-c1c3-9f2e-57a8-64741182a96e@arm.com> Date: Thu, 16 May 2019 19:02:05 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <1558024626-19395-1-git-send-email-lollivier@baylibre.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16/05/2019 17:37, Loys Ollivier wrote: > The default serial speed was hardcoded in the code. > Rename current-speed to default-speed. > Add a function parameter that lets the subdrivers specify their > default speed. > If not specified fallback to the device-tree default-speed. > > Signed-off-by: Loys Ollivier > --- > Hello, > > This patch moves the currently hardcoded, default serial speed > to the subdrivers. > If the default speed is not specified by the subdriver then it is read > from the device tree. > > Changes since v1[0] > - Use u32 data types instead of uint > > [0]: https://lore.kernel.org/lkml/1557322788-10403-1-git-send-email-lollivier@baylibre.com/ > > Cheers, > Loys > > drivers/gnss/mtk.c | 7 ++++++- > drivers/gnss/serial.c | 21 +++++++++++++-------- > drivers/gnss/serial.h | 3 ++- > drivers/gnss/ubx.c | 3 ++- > 4 files changed, 23 insertions(+), 11 deletions(-) > > diff --git a/drivers/gnss/mtk.c b/drivers/gnss/mtk.c > index d1fc55560daf..1d35bcb52072 100644 > --- a/drivers/gnss/mtk.c > +++ b/drivers/gnss/mtk.c > @@ -16,6 +16,10 @@ > > #include "serial.h" > > +static uint serial_speed = 9600; /* Serial speed (baud rate) */ > +module_param(serial_speed, uint, 0644); > +MODULE_PARM_DESC(serial_speed, "Serial baud rate (bit/s), (default = 9600)"); > + > struct mtk_data { > struct regulator *vbackup; > struct regulator *vcc; > @@ -69,7 +73,8 @@ static int mtk_probe(struct serdev_device *serdev) > struct mtk_data *data; > int ret; > > - gserial = gnss_serial_allocate(serdev, sizeof(*data)); > + gserial = gnss_serial_allocate(serdev, sizeof(*data), > + (u32)serial_speed); > if (IS_ERR(gserial)) { > ret = PTR_ERR(gserial); > return ret; > diff --git a/drivers/gnss/serial.c b/drivers/gnss/serial.c > index def64b36d994..3be799702291 100644 > --- a/drivers/gnss/serial.c > +++ b/drivers/gnss/serial.c > @@ -103,17 +103,13 @@ static int gnss_serial_set_power(struct gnss_serial *gserial, > return gserial->ops->set_power(gserial, state); > } > > -/* > - * FIXME: need to provide subdriver defaults or separate dt parsing from > - * allocation. > - */ > static int gnss_serial_parse_dt(struct serdev_device *serdev) > { > struct gnss_serial *gserial = serdev_device_get_drvdata(serdev); > struct device_node *node = serdev->dev.of_node; > - u32 speed = 4800; > + u32 speed; > > - of_property_read_u32(node, "current-speed", &speed); > + of_property_read_u32(node, "default-speed", &speed); > > gserial->speed = speed; Hmm, maybe it's a bit too convoluted for the compiler to warn about, but if a "default-speed" property is not present, gserial->speed will now be assigned an uninitialised value. I don't know what the intent is neither the driver nor the DT provides a value, but you'll either need to bring back the fallback initialisation above or propagate errors from of_property_read_u32(). Robin. > > @@ -121,7 +117,8 @@ static int gnss_serial_parse_dt(struct serdev_device *serdev) > } > > struct gnss_serial *gnss_serial_allocate(struct serdev_device *serdev, > - size_t data_size) > + size_t data_size, > + u32 serial_speed) > { > struct gnss_serial *gserial; > struct gnss_device *gdev; > @@ -146,10 +143,18 @@ struct gnss_serial *gnss_serial_allocate(struct serdev_device *serdev, > serdev_device_set_drvdata(serdev, gserial); > serdev_device_set_client_ops(serdev, &gnss_serial_serdev_ops); > > - ret = gnss_serial_parse_dt(serdev); > + /* Serial speed provided by subdriver takes precedence over dt*/ > + if (!serial_speed) > + ret = gnss_serial_parse_dt(serdev); > + else > + gserial->speed = serial_speed; > + > if (ret) > goto err_put_device; > > + if (!gserial->speed) > + return -EINVAL; > + > return gserial; > > err_put_device: > diff --git a/drivers/gnss/serial.h b/drivers/gnss/serial.h > index 980ffdc86c2a..17df61e399e6 100644 > --- a/drivers/gnss/serial.h > +++ b/drivers/gnss/serial.h > @@ -33,7 +33,8 @@ struct gnss_serial_ops { > extern const struct dev_pm_ops gnss_serial_pm_ops; > > struct gnss_serial *gnss_serial_allocate(struct serdev_device *gserial, > - size_t data_size); > + size_t data_size, > + u32 serial_speed); > void gnss_serial_free(struct gnss_serial *gserial); > > int gnss_serial_register(struct gnss_serial *gserial); > diff --git a/drivers/gnss/ubx.c b/drivers/gnss/ubx.c > index 7b05bc40532e..52ae6e4987e0 100644 > --- a/drivers/gnss/ubx.c > +++ b/drivers/gnss/ubx.c > @@ -68,8 +68,9 @@ static int ubx_probe(struct serdev_device *serdev) > struct gnss_serial *gserial; > struct ubx_data *data; > int ret; > + u32 speed = 4800; > > - gserial = gnss_serial_allocate(serdev, sizeof(*data)); > + gserial = gnss_serial_allocate(serdev, sizeof(*data), speed); > if (IS_ERR(gserial)) { > ret = PTR_ERR(gserial); > return ret; >