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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24F00C636D6 for ; Wed, 22 Feb 2023 11:17:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231783AbjBVLRQ (ORCPT ); Wed, 22 Feb 2023 06:17:16 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229901AbjBVLRN (ORCPT ); Wed, 22 Feb 2023 06:17:13 -0500 Received: from mx0b-001ae601.pphosted.com (mx0b-001ae601.pphosted.com [67.231.152.168]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E520F14497 for ; Wed, 22 Feb 2023 03:17:11 -0800 (PST) Received: from pps.filterd (m0077474.ppops.net [127.0.0.1]) by mx0b-001ae601.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 31M4vaUV024867; Wed, 22 Feb 2023 05:17:01 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cirrus.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=PODMain02222019; bh=Lzzmlg5/HaeQtJHe5cty00x/W7yYOagmQsJTM/6i9ok=; b=RQfx00sIJsMWeZ8OoF322Y2Y2q2reOuD4maS3OQIm+bg1M7NIKsGGQKIqHjCf4LYGQAY wOJyxxm0/essHbK/OgjTLA5mOd/+jvcF78pykUJyc7e1IYuEXnNB4K9FGELDQX3HDkDz 79kt1K+klU2ZnuurSv4o+2W0Ai+kC8u9GH0Z5YyReKKkJgpc+ELRE8hNBaskNeYjqCUf SUZhgK2fi2EFX+IXaOexr8Cvf1tB3RxQjXF1E7IRfwOwJzsasIT28S4i08PktAjLyBpZ lPrbhNlRFNcNKyam24U+PuY8BOjc1Xr9WiUqbgVfkyHxBtTzhWJOYasdlKUhokw0A7Vp 2A== Received: from ediex02.ad.cirrus.com ([84.19.233.68]) by mx0b-001ae601.pphosted.com (PPS) with ESMTPS id 3nvmnqsym0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 22 Feb 2023 05:17:00 -0600 Received: from ediex02.ad.cirrus.com (198.61.84.81) by ediex02.ad.cirrus.com (198.61.84.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.21; Wed, 22 Feb 2023 05:16:59 -0600 Received: from ediswmail.ad.cirrus.com (198.61.86.93) by anon-ediex02.ad.cirrus.com (198.61.84.81) with Microsoft SMTP Server id 15.2.1118.21 via Frontend Transport; Wed, 22 Feb 2023 05:16:59 -0600 Received: from [198.90.251.127] (edi-sw-dsktp-006.ad.cirrus.com [198.90.251.127]) by ediswmail.ad.cirrus.com (Postfix) with ESMTP id 4583A475; Wed, 22 Feb 2023 11:16:59 +0000 (UTC) Message-ID: <0f42c8fa-2c83-8ad0-7668-d7ba1a7dcbe2@opensource.cirrus.com> Date: Wed, 22 Feb 2023 11:16:59 +0000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Subject: Re: [PATCH 08/10] ASoC: cs35l56: Add driver for Cirrus Logic CS35L56 Content-Language: en-US To: Pierre-Louis Bossart , , , , , CC: , , References: <20230217161410.915202-1-rf@opensource.cirrus.com> <20230217161410.915202-9-rf@opensource.cirrus.com> <2d55b8c9-e7f9-6b2e-aad8-5cc902d69000@linux.intel.com> <59866a98-077a-4645-b85b-a18fc1d65a54@opensource.cirrus.com> <3b8dd6a8-363e-2c38-b1a5-5361fb7bff85@linux.intel.com> From: Richard Fitzgerald In-Reply-To: <3b8dd6a8-363e-2c38-b1a5-5361fb7bff85@linux.intel.com> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 8bit X-Proofpoint-ORIG-GUID: Psb6m09lpi5-ZIRlFzk9I3zIWc4B3843 X-Proofpoint-GUID: Psb6m09lpi5-ZIRlFzk9I3zIWc4B3843 X-Proofpoint-Spam-Reason: safe Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/02/2023 17:58, Pierre-Louis Bossart wrote: > > > On 2/21/23 12:18, Richard Fitzgerald wrote: >> On 21/02/2023 16:45, Pierre-Louis Bossart wrote: >>> >>>> +static int cs35l56_sdw_interrupt(struct sdw_slave *peripheral, >>>> +                 struct sdw_slave_intr_status *status) >>>> +{ >>>> +    struct cs35l56_private *cs35l56 = >>>> dev_get_drvdata(&peripheral->dev); >>>> + >>>> +    /* SoundWire core holds our pm_runtime when calling this >>>> function. */ >>>> + >>>> +    dev_dbg(cs35l56->dev, "int control_port=%#x\n", >>>> status->control_port); >>>> + >>>> +    if ((status->control_port & SDW_SCP_INT1_IMPL_DEF) == 0) >>>> +        return 0; >>>> + >>>> +    /* Prevent host controller suspending before we handle the >>>> interrupt */ >>>> +    pm_runtime_get_noresume(cs35l56->dev); >>> >>> can this happen that the manager suspends in this function? >>> >>> Or is this needed because of the queued work which the manager has no >>> knowledge of? >>> >> >> Because you issue a Bus-Reset when you suspend and clock-stop, if we >> didn't take our pm_runtime there is a small window of time where we >> could be reset before we've handled the interrupt. It's unlikely to >> happen but better to be safe than to rely on autosuspend delays. > > What I meant is that the pm_runtime refcount should be increased prior > to the SoundWire core using the interrupt_callback. > > So the only window I see is in the second part of in the interrupt > handling, before the workqueue is scheduled. Yes, sorry I didn't explain well. It's because we defer the handling to a workqueue job. It's to prevent the (small) chance of runtime-suspending and clock-stopping before the work queue function has had time to process the interrupt. It only matters because the Intel controller issues a Bus-Reset when it comes out of clock stop. >> >>>> + >>>> +    /* >>>> +     * Mask and clear until it has been handled. The read of >>>> GEN_INT_STAT_1 >>>> +     * is required as per the SoundWire spec for interrupt status bits >>>> +     * to clear. GEN_INT_MASK_1 masks the _inputs_ to GEN_INT_STAT1. >>>> +     * None of the interrupts are time-critical so use the >>>> +     * power-efficient queue. >>>> +     */ >>>> +    sdw_write_no_pm(peripheral, CS35L56_SDW_GEN_INT_MASK_1, 0); >>>> +    sdw_read_no_pm(peripheral, CS35L56_SDW_GEN_INT_STAT_1); >>>> +    sdw_write_no_pm(peripheral, CS35L56_SDW_GEN_INT_STAT_1, 0xFF); >>>> +    queue_work(system_power_efficient_wq, &cs35l56->sdw_irq_work); >>>> + >>>> +    return 0; >>>> +} >>> >>>> +static int __maybe_unused cs35l56_sdw_handle_unattach(struct >>>> cs35l56_private *cs35l56) >>>> +{ >>>> +    struct sdw_slave *peripheral = cs35l56->sdw_peripheral; >>>> + >>>> +    if (peripheral->unattach_request) { >>>> +        /* Cannot access registers until master re-attaches. */ >>> >>> not sure what the comment means, the manager does not attach. did you >>> mean resume the bus? >>> >> >> If the manager has forced us to reset we can't access the registers >> until the manager has recovered its state. > > "until the manager restarted the bus and re-enumerated devices" ? > I'll re-word the comment. And also change to "manager". >> >>>> +        dev_dbg(cs35l56->dev, "Wait for initialization_complete\n"); >>>> +        if >>>> (!wait_for_completion_timeout(&peripheral->initialization_complete, >>>> +                         msecs_to_jiffies(5000))) { >>>> +            dev_err(cs35l56->dev, "initialization_complete timed >>>> out\n"); >>>> +            return -ETIMEDOUT; >>>> +        } >>>> + >>>> +        peripheral->unattach_request = 0; >>>> + >>>> +        /* >>>> +         * Don't call regcache_mark_dirty(), we can't be sure that the >>>> +         * Manager really did issue a Bus Reset. >>>> +         */ >>>> +    } >>>> + >>>> +    return 0; >>>> +} >>> ... >>> >>>> +static void cs35l56_dsp_work(struct work_struct *work) >>>> +{ >>>> +    struct cs35l56_private *cs35l56 = container_of(work, >>>> +                               struct cs35l56_private, >>>> +                               dsp_work); >>>> +    unsigned int reg; >>>> +    unsigned int val; >>>> +    int ret = 0; >>>> + >>>> +    if (!wait_for_completion_timeout(&cs35l56->init_completion, >>>> +                     msecs_to_jiffies(5000))) { >>>> +        dev_err(cs35l56->dev, "%s: init_completion timed out\n", >>>> __func__); >>>> +        goto complete; >>>> +    } >>>> + >>>> +    if (!cs35l56->init_done || cs35l56->removing) >>>> +        goto complete; >>>> + >>>> +    cs35l56->dsp.part = devm_kasprintf(cs35l56->dev, GFP_KERNEL, >>>> "cs35l56%s-%02x", >>>> +                       cs35l56->secured ? "s" : "", cs35l56->rev); >>>> + >>>> +    if (!cs35l56->dsp.part) >>>> +        goto complete; >>>> + >>>> +    pm_runtime_get_sync(cs35l56->dev); >>> >>> test that this is successful? >>> >> >> Could do. Wasn't really expecting it to fail unless the hardware is >> already broken. > > it's not supposed to happen indeed, but our CI caught a couple of issues > over the last two years. Better add a check. > No harm in checking for error. >> >>>> + >>>> +    /* >>>> +     * Disable SoundWire interrupts to prevent race with IRQ work. >>>> +     * Setting sdw_irq_no_unmask prevents the handler re-enabling >>>> +     * the SoundWire interrupt. >>>> +     */ >>>> +    if (cs35l56->sdw_peripheral) { >>>> +        cs35l56->sdw_irq_no_unmask = true; >>>> +        cancel_work_sync(&cs35l56->sdw_irq_work); >>>> +        sdw_write_no_pm(cs35l56->sdw_peripheral, >>>> CS35L56_SDW_GEN_INT_MASK_1, 0); >>>> +        sdw_read_no_pm(cs35l56->sdw_peripheral, >>>> CS35L56_SDW_GEN_INT_STAT_1); >>>> +        sdw_write_no_pm(cs35l56->sdw_peripheral, >>>> CS35L56_SDW_GEN_INT_STAT_1, 0xFF); >>>> +    } >>>> + >>>> +    ret = cs35l56_mbox_send(cs35l56, CS35L56_MBOX_CMD_SHUTDOWN); >>>> +    if (ret) { >>>> +        dev_dbg(cs35l56->dev, "%s: CS35L56_MBOX_CMD_SHUTDOWN ret >>>> %d\n", __func__, ret); >>>> +        goto err; >>>> +    } >>>> + >>>> +    if (cs35l56->rev < CS35L56_REVID_B0) >>>> +        reg = CS35L56_DSP1_PM_CUR_STATE_A1; >>>> +    else >>>> +        reg = CS35L56_DSP1_PM_CUR_STATE; >>>> + >>>> +    ret = regmap_read_poll_timeout(cs35l56->regmap, reg, >>>> +                       val, (val == CS35L56_HALO_STATE_SHUTDOWN), >>>> +                       CS35L56_HALO_STATE_POLL_US, >>>> +                       CS35L56_HALO_STATE_TIMEOUT_US); >>>> +    if (ret < 0) >>>> +        dev_err(cs35l56->dev, "Failed to poll PM_CUR_STATE to 1 is >>>> %d (ret %d)\n", >>>> +            val, ret); >>>> + >>>> +    /* Use wm_adsp to load and apply the firmware patch and >>>> coefficient files */ >>>> +    ret = wm_adsp_power_up(&cs35l56->dsp); >>>> +    if (ret) { >>>> +        dev_dbg(cs35l56->dev, "%s: wm_adsp_power_up ret %d\n", >>>> __func__, ret); >>>> +        goto err; >>>> +    } >>>> + >>>> +    if (cs35l56->removing) >>>> +        goto err; >>>> + >>>> +    mutex_lock(&cs35l56->irq_lock); >>>> + >>>> +    init_completion(&cs35l56->init_completion); >>>> + >>>> +    cs35l56_system_reset(cs35l56); >>>> + >>>> +    if (cs35l56->sdw_peripheral) { >>>> +        if (!wait_for_completion_timeout(&cs35l56->init_completion, >>>> +                         msecs_to_jiffies(5000))) { >>>> +            dev_err(cs35l56->dev, "%s: init_completion timed out >>>> (SDW)\n", __func__); >>> >>> shouldn't do the same routine as for a regular pm_runtime resume, >>> including re-synching regmaps? >>> >> >> Not sure it would help. It's not the same as runtime_resume because >> we've changed the firmware and rebooted it (the firmware is retained >> in a runtime_suspend). We need to do some of the first-time init() >> code again, which we don't need to do in runtime_resume. >> >> Also would create a circular dependency between this driver and the >> cs35l56-sdw driver. (We _could_ call our dev->pm->runtime_resume pointer >> but that's a bit ugly) > > I wasn't suggesting using a pm_runtime suspend/resume cycle but rather > use a common helper called from here and from the pm_runtime_resume. > > It's a suggestion only. > It's on my to-do list to see whether this is useful. Effectively we're re-initializing and the code we want to re-use is what cs35l56_init() does after it issues SYSTEM_RESET. So cs35l56_init() is acting as the common code. We're going to get an update_status() callback when it re-enumerates. The update_status() calls cs35l56_init() during the first enumeration. So we are re-using that same code path to call again cs35l56_init() and repeat the post-SYSTEM_RESET handling. >> >>> >>>> +            goto err_unlock; >>>> +        } >>>> +    } else { >>>> +        if (cs35l56_init(cs35l56)) >>>> +            goto err_unlock; >>>> +    } >>>> + >>>> +    cs35l56->fw_patched = true; >>>> + >>>> +err_unlock: >>>> +    mutex_unlock(&cs35l56->irq_lock); >>>> +err: >>>> +    pm_runtime_mark_last_busy(cs35l56->dev); >>>> +    pm_runtime_put_autosuspend(cs35l56->dev); >>>> + >>>> +    /* Re-enable SoundWire interrupts */ >>>> +    if (cs35l56->sdw_peripheral) { >>>> +        cs35l56->sdw_irq_no_unmask = false; >>>> +        sdw_write_no_pm(cs35l56->sdw_peripheral, >>>> CS35L56_SDW_GEN_INT_MASK_1, >>>> +                CS35L56_SDW_INT_MASK_CODEC_IRQ); >>>> +    } >>>> + >>>> +complete: >>>> +    complete_all(&cs35l56->dsp_ready_completion); >>>> +}