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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 2A0D2C43387 for ; Wed, 16 Jan 2019 20:23:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E232020840 for ; Wed, 16 Jan 2019 20:23:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Ys6yE7gB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731741AbfAPUW4 (ORCPT ); Wed, 16 Jan 2019 15:22:56 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:43119 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730050AbfAPUW4 (ORCPT ); Wed, 16 Jan 2019 15:22:56 -0500 Received: by mail-pl1-f194.google.com with SMTP id gn14so3533878plb.10 for ; Wed, 16 Jan 2019 12:22:55 -0800 (PST) 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=ATF5Lt37lZd4XR74weI4YdFP5xD4fmjGIe3UjfXgJs0=; b=Ys6yE7gBUdham7sCbDYYl11kLIa783zCix6NZY6wSopEKMswotxOPX72RIau9tLorw DgXo9dA18KrdLiTuLCrCzThRVMww1nd7ysfTAsrLJ3tXtBAr/J6uIcr9KElWzXcQX7ga M+et3ytePBaFUe9nNwLd7/EeOUuZoWsWvTPs0= 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=ATF5Lt37lZd4XR74weI4YdFP5xD4fmjGIe3UjfXgJs0=; b=fsCdXcoEc+zlGCI3RbRi3UskK5p9w4HfWAoaG6SWVPUXiU/eibhA8Oi2VO2q0bVFmt j/ZvuVXsJ5IdMLDlI+q+jG2/j4DDZgcQSFxFxD1ZVf9XJbbHHghP/3T0Drr7i07E6h8y fh0z2Z7BlUilaJGgbsATVfmXuR32YdeyOp8KVkvh4CPCQG1xkqNYfsum/fDSoCPWJNI+ kNpn5b+VJLvfeGwUNxJAljDIsfx6CoJKhI2XeSenJz1lJFpC4rV2tySdm3WTc37r6Wng b8ugrWo59unBifMnx1rbeUpAybL+CZMUxWqrz3zshj4Ieq1/cMqANncbtHzrzMXOCKsd 2vvw== X-Gm-Message-State: AJcUukdE2gBuAn47fUE1A4zT4O8dTmNcraQinJn4Ac2PFo1TbYyY409z LAgjW9CQNY+J+4RXWlwUTv9b9g== X-Google-Smtp-Source: ALg8bN4pJ040ecnF/7FzaQXtnqodtpti32I7WuYPl7fiovVlgvXoKdQZPcjhefmCzNbqbTt7h/CBNQ== X-Received: by 2002:a17:902:b03:: with SMTP id 3mr11614360plq.91.1547670175228; Wed, 16 Jan 2019 12:22:55 -0800 (PST) Received: from localhost ([2620:15c:202:1:75a:3f6e:21d:9374]) by smtp.gmail.com with ESMTPSA id i184sm9684698pfc.41.2019.01.16.12.22.53 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 16 Jan 2019 12:22:54 -0800 (PST) Date: Wed, 16 Jan 2019 12:22:53 -0800 From: Matthias Kaehlcke To: Balakrishna Godavarthi Cc: marcel@holtmann.org, johan.hedberg@gmail.com, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCH v8 1/3] Bluetooth: hci_qca: use wait_until_sent() for power pulses Message-ID: <20190116202253.GS261387@google.com> References: <20190116114603.500-1-bgodavar@codeaurora.org> <20190116114603.500-2-bgodavar@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190116114603.500-2-bgodavar@codeaurora.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-bluetooth-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org On Wed, Jan 16, 2019 at 05:16:01PM +0530, Balakrishna Godavarthi wrote: > wcn3990 requires a power pulse to turn ON/OFF along with > regulators. Sometimes we are observing the power pulses are sent > out with some time delay, due to queuing these commands. This is > causing synchronization issues with chip, which intern delay the > chip setup or may end up with communication issues. > > Signed-off-by: Balakrishna Godavarthi > --- > Changes in v8: > * Updated 1 second timeout instead of indefinite wait. > > Changes in v7: > * updated the wait time to 5 ms after sending power pulses. > > Changes in v6: > * added serdev_device_write_flush() in qca_send_power_pulse > instead during the power off pulse. > > Changes in v5: > * added serdev_device_write_flush() in qca_power_off(). > --- > drivers/bluetooth/hci_qca.c | 46 ++++++++++++++++--------------------- > 1 file changed, 20 insertions(+), 26 deletions(-) > > diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c > index f036c8f98ea3..681bfa30467e 100644 > --- a/drivers/bluetooth/hci_qca.c > +++ b/drivers/bluetooth/hci_qca.c > @@ -60,6 +60,7 @@ > #define IBS_WAKE_RETRANS_TIMEOUT_MS 100 > #define IBS_TX_IDLE_TIMEOUT_MS 2000 > #define BAUDRATE_SETTLE_TIMEOUT_MS 300 > +#define POWER_PULSE_TRANS_TIMEOUT_MS 1000 nit: Not that it should make a different in normal operation, but 1s seems extreme. Is there really any chance that the byte hasn't been sent after say 100ms (which is still an eternity for a single byte)? > /* susclk rate */ > #define SUSCLK_RATE_32KHZ 32768 > @@ -1013,11 +1014,10 @@ static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed) > hci_uart_set_baudrate(hu, speed); > } > > -static int qca_send_power_pulse(struct hci_dev *hdev, u8 cmd) > +static int qca_send_power_pulse(struct hci_uart *hu, u8 cmd) > { > - struct hci_uart *hu = hci_get_drvdata(hdev); > - struct qca_data *qca = hu->priv; > - struct sk_buff *skb; > + int ret; > + int timeout = __msecs_to_jiffies(POWER_PULSE_TRANS_TIMEOUT_MS); use msecs_to_jiffies() > /* These power pulses are single byte command which are sent > * at required baudrate to wcn3990. On wcn3990, we have an external > @@ -1029,22 +1029,22 @@ static int qca_send_power_pulse(struct hci_dev *hdev, u8 cmd) > * save power. Disabling hardware flow control is mandatory while > * sending power pulses to SoC. > */ > - bt_dev_dbg(hdev, "sending power pulse %02x to SoC", cmd); > - > - skb = bt_skb_alloc(sizeof(cmd), GFP_KERNEL); > - if (!skb) > - return -ENOMEM; > + bt_dev_dbg(hu->hdev, "sending power pulse %02x to controller", cmd); > > + serdev_device_write_flush(hu->serdev); > hci_uart_set_flow_control(hu, true); > + ret = serdev_device_write_buf(hu->serdev, &cmd, sizeof(cmd)); > + if (ret < 0) { > + bt_dev_err(hu->hdev, "failed to send power pulse %02x", cmd); > + return ret; > + } > > - skb_put_u8(skb, cmd); > - hci_skb_pkt_type(skb) = HCI_COMMAND_PKT; > - > - skb_queue_tail(&qca->txq, skb); > - hci_uart_tx_wakeup(hu); > - > - /* Wait for 100 uS for SoC to settle down */ > - usleep_range(100, 200); > + serdev_device_wait_until_sent(hu->serdev, timeout); > + /* Wait of 5ms is required for assuring to send the byte on the Tx > + * line and also for the controller to settle down for the received > + * byte. > + */ > + usleep_range(5000, 6000); I incorrectly claimed that there might be still bytes sitting in the UART FIFO when serdev_device_wait_until_sent() returns, Johan corrected me on that (thanks!). So if it takes the SoC 100us to settle down we should be good with the original code. Cheers Matthias