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 15FD2C43142 for ; Mon, 25 Jun 2018 23:44:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2324262D0 for ; Mon, 25 Jun 2018 23:44:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="cCwKAqYo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B2324262D0 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 S933659AbeFYXoA (ORCPT ); Mon, 25 Jun 2018 19:44:00 -0400 Received: from mail-pl0-f65.google.com ([209.85.160.65]:33367 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754781AbeFYXn4 (ORCPT ); Mon, 25 Jun 2018 19:43:56 -0400 Received: by mail-pl0-f65.google.com with SMTP id 6-v6so7581152plb.0 for ; Mon, 25 Jun 2018 16:43:56 -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=asj2qQcV72Hx4n3Mpezs5s9gXKNvNC3eYxQiPgPnN30=; b=cCwKAqYokJL5a2O9XFBY9jXggUeofb11XYL+PI+kdBZ89DH7A4wOHx/7txle+wUljT x9z//uve7hDZKmfVWVb9Lx1aDeo5bVhxsy8Lh8Dx7h8FV4907brTrWSjjd/848RhCMaq vxnjD0l1r0rVF5eJsVMiggQUIVIRl1O+Ec6gw= 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=asj2qQcV72Hx4n3Mpezs5s9gXKNvNC3eYxQiPgPnN30=; b=Y3cqv3QoWXTJw9Vw8zDg8xa9uMpYk5kBFCgIs1Irz/jhJNnf5YolQ+rHt6oadTyMOt hmTSgQRkzoLy2WPo8HR6kVQ+q+kbRIC928NXVFHlt/sOn6lMoIfO55crMrYgToQHd9u0 c1cKGEWPlP+pDgMouUROx/s62DPFaH1H1GxiRkAsjieCgrgMG74HR0uEOH8t2Mrnkzbc g3hkolDsS5TYYe4dcEJkQgywBGoI4UX6QSJP3Ed0TJfynyA8OdVkeafb9Xw88qhzlOun lZwQUcOCeg4+lohsinMMH7cNVPIHV5FP4PbgmAGXtXEeXwMjZuvhxEDQynC2gJEP0lYQ GD+g== X-Gm-Message-State: APt69E3EFAaDD5LO4ErWcMhmkstfL+OzjMHmb1nJIT//bmJsColHTr2C nfK9nly1Xa8ne3FZBb8XZhT9WA== X-Google-Smtp-Source: ADUXVKKm3CjiZurBHnTzSxk2AvATZaTZa6WwFqMEwUZaEpKcMrAcnWZWyM7Hv5zqEHMu3XYpE7i08w== X-Received: by 2002:a17:902:b28:: with SMTP id 37-v6mr14013889plq.201.1529970235899; Mon, 25 Jun 2018 16:43:55 -0700 (PDT) Received: from localhost ([2620:0:1000:1501:8e2d:4727:1211:622]) by smtp.gmail.com with ESMTPSA id z3-v6sm186752pfn.36.2018.06.25.16.43.55 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 25 Jun 2018 16:43:55 -0700 (PDT) Date: Mon, 25 Jun 2018 16:43:54 -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: <20180625234354.GI129942@google.com> References: <20180625134013.19684-1-bgodavar@codeaurora.org> <20180625134013.19684-5-bgodavar@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180625134013.19684-5-bgodavar@codeaurora.org> 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 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? > + > static int qca_setup(struct hci_uart *hu) > { > struct hci_dev *hdev = hu->hdev; > @@ -937,35 +996,17 @@ static int qca_setup(struct hci_uart *hu) > clear_bit(STATE_IN_BAND_SLEEP_ENABLED, &qca->flags); > > /* Setup initial baudrate */ > - speed = 0; > - if (hu->init_speed) > - speed = hu->init_speed; > - else if (hu->proto->init_speed) > - speed = hu->proto->init_speed; > - > - if (speed) > - host_set_baudrate(hu, speed); > + qca_set_speed(hu, QCA_INIT_SPEED); > > /* Setup user speed if needed */ > - speed = 0; > - if (hu->oper_speed) > - speed = hu->oper_speed; > - else if (hu->proto->oper_speed) > - speed = hu->proto->oper_speed; > + ret = qca_set_speed(hu, QCA_OPER_SPEED); > + if (ret) > + return ret; > > - if (speed) { > + speed = qca_get_speed(hu, QCA_OPER_SPEED); > + if (speed) > qca_baudrate = qca_get_baudrate_value(speed); Is the check here necessary? qca_get_baudrate_value() returns QCA_BAUDRATE_115200 for a zero speed.