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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT 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 BF9A3C43144 for ; Tue, 26 Jun 2018 00:05:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 75172262BB for ; Tue, 26 Jun 2018 00:05:34 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Dgn+sf59" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 75172262BB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755781AbeFZAFd (ORCPT ); Mon, 25 Jun 2018 20:05:33 -0400 Received: from mail-pl0-f67.google.com ([209.85.160.67]:45945 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754980AbeFZAFb (ORCPT ); Mon, 25 Jun 2018 20:05:31 -0400 Received: by mail-pl0-f67.google.com with SMTP id o18-v6so6906224pll.12 for ; Mon, 25 Jun 2018 17:05:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=9Ezy/Lem0rIEKXNibWSZX7yYpcuQTIvqQqWys6W340k=; b=Dgn+sf59t0ximuB0zH8r3Dv/Oj+K2ln8bwohe/7pJaJ0VTkCWXejBZiuAYk0B8wIkR pxC0FJAZwxkzkW0Jcnl8TJabGnVEGhuJeKgTvheen/lk7vqaL7qWlzSfrYqByQq/4Gbq fgsMaWyR6lkXf3fC1zjZ5vNZQ5hL/z80y/kng= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=9Ezy/Lem0rIEKXNibWSZX7yYpcuQTIvqQqWys6W340k=; b=mu+uV8OWG0mM7qba1n9crds6sKugDkY6pRKNyfSFZW5wCDqYUzaQlJQHVD3/x9PScw MQViLFBYR3IBnthN7GOhNl69HXEf0wP1djH6FtD7CQcI0YBV6VJxumzUEhjrNQsk4ScG JQ5EC49Civ6nIVhe9dTHh5+/YOCaPzcJ69bJp3Kbvm2udm7szdBJuuRQUosrSokrmD3c HUWm5c/O6tCTbnKtAkiitZw928EnEcJlxVRdiAUGFUpg3KLj2vCzRcMJOuvEgUyFaHi6 Y5PX/lhc33DiWxoFGQ8AxQhTw+mzhY0ckl6wOV49+7SGCjUDKLWOZaUUyb9MVRB8hP4g JoRw== X-Gm-Message-State: APt69E0Lbek4hXxzxe4jSHsaUXyWKwkSH/UAylbqozDUt+va39ujlzg2 bJmi0i8Be3Gm1Rn497B0u3RfFw== X-Google-Smtp-Source: ADUXVKKtSbCPSHDV9h8u7RoV5iSyayFfwgkGg5Dq/32TDfgDZZK7UsCsZ3tVEeERZCVSfYPCGK52eA== X-Received: by 2002:a17:902:8b8c:: with SMTP id ay12-v6mr14382186plb.74.1529971530572; Mon, 25 Jun 2018 17:05:30 -0700 (PDT) Received: from localhost ([2620:0:1000:1501:8e2d:4727:1211:622]) by smtp.gmail.com with ESMTPSA id x2-v6sm176345pgq.33.2018.06.25.17.05.29 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 25 Jun 2018 17:05:29 -0700 (PDT) Date: Mon, 25 Jun 2018 17:05:29 -0700 From: Matthias Kaehlcke To: Balakrishna Godavarthi Cc: marcel@holtmann.org, johan.hedberg@gmail.com, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-bluetooth@vger.kernel.org, rtatiya@codeaurora.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v8 4/7] Bluetooth: hci_qca: Add wrapper functions for setting UART speed Message-ID: <20180626000529.GJ129942@google.com> References: <20180625134013.19684-1-bgodavar@codeaurora.org> <20180625134013.19684-5-bgodavar@codeaurora.org> <20180625234354.GI129942@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180625234354.GI129942@google.com> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 25, 2018 at 04:43:54PM -0700, Matthias Kaehlcke wrote: > This is a nice improvement, a few remaining questions inline. > > On Mon, Jun 25, 2018 at 07:10:10PM +0530, Balakrishna Godavarthi wrote: > > In function qca_setup, we set initial and operating speeds for Qualcomm > > Bluetooth SoC's. This block of code is common across different > > Qualcomm Bluetooth SoC's. Instead of duplicating the code, created > > a wrapper function to set the speeds. So that future coming SoC's > > can use these wrapper functions to set speeds. > > > > Signed-off-by: Balakrishna Godavarthi > > --- > > Changes in v8: > > * common function to set INIT and operating speeds. > > * moved hardware flow control to qca_set_speed(). > > > > Changes in v7: > > * initial patch > > * created wrapper functions for init and operating speeds. > > --- > > drivers/bluetooth/hci_qca.c | 89 +++++++++++++++++++++++++++---------- > > 1 file changed, 65 insertions(+), 24 deletions(-) > > > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > > index fe62420ef838..38b7dbe6c897 100644 > > --- a/drivers/bluetooth/hci_qca.c > > +++ b/drivers/bluetooth/hci_qca.c > > @@ -119,6 +119,11 @@ struct qca_data { > > u64 votes_off; > > }; > > > > +enum qca_speed_type { > > + QCA_INIT_SPEED = 1, > > + QCA_OPER_SPEED > > +}; > > + > > struct qca_serdev { > > struct hci_uart serdev_hu; > > struct gpio_desc *bt_en; > > @@ -923,6 +928,60 @@ static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed) > > hci_uart_set_baudrate(hu, speed); > > } > > > > +static unsigned int qca_get_speed(struct hci_uart *hu, > > + enum qca_speed_type speed_type) > > +{ > > + unsigned int speed = 0; > > + > > + if (speed_type == QCA_INIT_SPEED) { > > + if (hu->init_speed) > > + speed = hu->init_speed; > > + else if (hu->proto->init_speed) > > + speed = hu->proto->init_speed; > > + } else { > > + if (hu->oper_speed) > > + speed = hu->oper_speed; > > + else if (hu->proto->oper_speed) > > + speed = hu->proto->oper_speed; > > + } > > + > > + return speed; > > +} > > + > > +static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type) > > +{ > > + unsigned int speed, qca_baudrate; > > + int ret; > > + > > + if (speed_type == QCA_INIT_SPEED) { > > + speed = qca_get_speed(hu, QCA_INIT_SPEED); > > + if (speed) > > + host_set_baudrate(hu, speed); > > + else > > + bt_dev_err(hu->hdev, "Init speed should be non zero"); > > The check for 'speed == 0' is done in multiple places. From this > code I deduce that it is expected that both INIT and OPER speed are > set to non-zero values. What happens if either of them is zero? Is the > driver still operational? > > > + return 0; > > + } > > + > > + speed = qca_get_speed(hu, QCA_OPER_SPEED); > > + if (!speed) { > > + bt_dev_err(hu->hdev, "operating speed should be non zero"); > > + return 0; > > + } > > + > > + qca_baudrate = qca_get_baudrate_value(speed); > > + bt_dev_info(hu->hdev, "Set UART speed to %d", speed); > > + ret = qca_set_baudrate(hu->hdev, qca_baudrate); > > + if (ret) { > > + bt_dev_err(hu->hdev, "Failed to change the baudrate (%d)", ret); > > + return ret; > > + } > > + > > + host_set_baudrate(hu, speed); > > + > > + return ret; > > +} > > In the discussion on "[v7,8/8] Bluetooth: hci_qca: Add support for > Qualcomm Bluetooth chip wcn3990" you mentioned the possbility to move > the hci_uart_set_flow_control() calls into _set_speed(). This seemed > interesting but finally it isn't done in this series. Did you > encounter that it is not feasible/desirable for some reason? I got that half wrong. "[v8,7/7] Bluetooth: hci_qca: Add support for Qualcomm Bluetooth chip wcn3990" adds the flow control calls to _set_speed() however there are still_set_flow_control() calls in qca_setup(), which confused/s me. Could you provide a brief summary on the situations (relevant for this driver) in which flow controls needs to be enabled/disabled?