From patchwork Sun Sep 22 17:50:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gwendal Grignou X-Patchwork-Id: 11155939 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 712D618B6 for ; Sun, 22 Sep 2019 17:51:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 45060206C2 for ; Sun, 22 Sep 2019 17:51:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Fs0+cF47" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388318AbfIVRvQ (ORCPT ); Sun, 22 Sep 2019 13:51:16 -0400 Received: from mail-pg1-f196.google.com ([209.85.215.196]:42027 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388304AbfIVRvP (ORCPT ); Sun, 22 Sep 2019 13:51:15 -0400 Received: by mail-pg1-f196.google.com with SMTP id z12so6546142pgp.9 for ; Sun, 22 Sep 2019 10:51:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=kTiQ68frH3buw5AgdsTOxXme2f3OYqnBesTw4EkVXt8=; b=Fs0+cF47yYRE/Wk++9WI2oKRxYF0iPmEHMF0kHAaALMIlGbWFQbVSeq8ksUV7gg6UM 6mzzm87J8xfQL1cwwICKppnOCyebz5ZS7sGC8q37zaeS5jTd9ySlBnCHNspDGfMpnxK6 xnGJh0SXy4wEpHDaG41HGy/JaXbymzCI/2eYo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=kTiQ68frH3buw5AgdsTOxXme2f3OYqnBesTw4EkVXt8=; b=a39tKweuKHSLRurZ98/5mooGh5yJ+1O4q9y8kBRkBlwMjCOMLp8fWV215Cqw2UKwB9 auQNbfmr35qghG2qZ2sfou98+aCMF/lR7xuIrRd0OwCaXeMs0c3QA+l5pBs0wT8uuDwc mT1EgJNBAS5pNAOZMscub46TPVaZVR9Tb74OY/RXOXA9mNOE5L8VzFnffuwsfLSPcUBO eA4ptpTAUgxn/N0+58oIrABVx79VqKF51ynqL+5nqfuMTG61YebPfOrl9fGGvLnMH42C Ys1Wdan6GGE1DJzpLYrsLWIA1j3q79Faa3vspudH7Y+1nToqOjHdq0sXciVDSYuJ56q7 a+fQ== X-Gm-Message-State: APjAAAWto7r6ohSvSONGXeSqEXGk7yRj48C6jbKgVohItxzCczd0En+F skQaK8o3iqjn61kNay2spT/5hA== X-Google-Smtp-Source: APXvYqziDj7V3++B47qgn7FZbocvdw+ms+0j0UipWRymV8SecRXLRGfCv4v62H3s+lRpEI3qrU8+ow== X-Received: by 2002:a17:90a:bf0e:: with SMTP id c14mr16069434pjs.69.1569174673233; Sun, 22 Sep 2019 10:51:13 -0700 (PDT) Received: from localhost ([2620:15c:202:1:3c8f:512b:3522:dfaf]) by smtp.gmail.com with ESMTPSA id a17sm8644598pfi.178.2019.09.22.10.51.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 22 Sep 2019 10:51:12 -0700 (PDT) From: Gwendal Grignou To: jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, lee.jones@linaro.org, bleung@chromium.org, enric.balletbo@collabora.com, dianders@chromium.org, groeck@chromium.org, fabien.lahoudere@collabora.com Cc: linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Gwendal Grignou Subject: [PATCH 08/13] platform: chrome: sensorhub: Add code to spread timestmap Date: Sun, 22 Sep 2019 10:50:16 -0700 Message-Id: <20190922175021.53449-9-gwendal@chromium.org> X-Mailer: git-send-email 2.23.0.351.gc4317032e6-goog In-Reply-To: <20190922175021.53449-1-gwendal@chromium.org> References: <20190922175021.53449-1-gwendal@chromium.org> MIME-Version: 1.0 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org EC FIFO can send sensor events in batch. Spread them based on previous (TSa) and currnet timestamp (TSb) EC FIFO iio events +-----------+ | TSa | +-----------+ +---------------------------------------+ | event 1 | | event 1 | TSb - (TSb - TSa)/n * (n-1) | +-----------+ +---------------------------------------+ | event 2 | | event 2 | TSb - (TSb - TSa)/n * (n-2) | +-----------+ +---------------------------------------+ | ... | ------> | .... | | +-----------+ +---------------------------------------+ | event n-1 | | event 2 | TSb - (TSb - TSa)/n | +-----------+ +---------------------------------------+ | event n | | event 2 | TSb | +-----------+ +---------------------------------------+ | TSb | +-----------+ Signed-off-by: Gwendal Grignou Reviewed-by: Jonathan Cameron --- .../platform/chrome/cros_ec_sensorhub_ring.c | 99 ++++++++++++++++++- 1 file changed, 96 insertions(+), 3 deletions(-) diff --git a/drivers/platform/chrome/cros_ec_sensorhub_ring.c b/drivers/platform/chrome/cros_ec_sensorhub_ring.c index 8cd533d5542e..48327e80a5a3 100644 --- a/drivers/platform/chrome/cros_ec_sensorhub_ring.c +++ b/drivers/platform/chrome/cros_ec_sensorhub_ring.c @@ -160,6 +160,97 @@ static bool cros_ec_ring_process_event( return true; } +/* + * cros_ec_ring_spread_add: Calculate proper timestamps then + * add to ringbuffer (legacy). + * + * If there is a sample with a proper timestamp + * timestamp | count + * older_unprocess_out --> TS1 | 1 + * TS1 | 2 + * out --> TS1 | 3 + * next_out --> TS2 | + * We spread time for the samples [older_unprocess_out .. out] + * between TS1 and TS2: [TS1+1/4, TS1+2/4, TS1+3/4, TS2]. + * + * If we reach the end of the samples, we compare with the + * current timestamp: + * + * older_unprocess_out --> TS1 | 1 + * TS1 | 2 + * out --> TS1 | 3 + * We know have [TS1+1/3, TS1+2/3, current timestamp] + */ +static void cros_ec_ring_spread_add( + struct cros_ec_sensorhub *sensorhub, + unsigned long sensor_mask, + s64 current_timestamp, + struct cros_ec_sensors_ring_sample *last_out) +{ + struct cros_ec_sensors_ring_sample *out; + int i; + + for_each_set_bit(i, &sensor_mask, BITS_PER_LONG) { + s64 older_timestamp; + s64 timestamp; + struct cros_ec_sensors_ring_sample *older_unprocess_out = + sensorhub->ring; + struct cros_ec_sensors_ring_sample *next_out; + int count = 1; + + for (out = sensorhub->ring; out < last_out; out = next_out) { + s64 time_period; + + next_out = out + 1; + if (out->sensor_id != i) + continue; + + /* Timestamp to start with */ + older_timestamp = out->timestamp; + + /* find next sample */ + while (next_out < last_out && next_out->sensor_id != i) + next_out++; + + if (next_out >= last_out) { + timestamp = current_timestamp; + } else { + timestamp = next_out->timestamp; + if (timestamp == older_timestamp) { + count++; + continue; + } + } + + /* + * The next sample has a new timestamp, + * spread the unprocessed samples. + */ + if (next_out < last_out) + count++; + time_period = div_s64(timestamp - older_timestamp, + count); + + for (; older_unprocess_out <= out; + older_unprocess_out++) { + if (older_unprocess_out->sensor_id != i) + continue; + older_timestamp += time_period; + older_unprocess_out->timestamp = + older_timestamp; + } + count = 1; + /* The next_out sample has a valid timestamp, skip. */ + next_out++; + older_unprocess_out = next_out; + } + } + + /* push the event into the kfifo */ + for (out = sensorhub->ring; out < last_out; out++) + cros_sensorhub_send_sample(sensorhub, out); +} + /* * cros_ec_sensorhub_ring_handler - the trigger handler function * @@ -280,9 +371,11 @@ static void cros_ec_sensorhub_ring_handler(struct cros_ec_sensorhub *sensorhub) } } - /* push the event into the kfifo */ - for (out = sensorhub->ring; out < last_out; out++) - cros_sensorhub_send_sample(sensorhub, out); + /* + * Spread samples in case of batching, then add them to the ringbuffer. + */ + cros_ec_ring_spread_add(sensorhub, sensor_mask, + current_timestamp, last_out); ring_handler_end: sensorhub->fifo_timestamp[LAST_TS] = current_timestamp;