From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-lf2-f12.google.com (mail-lf2-f12.google.com [74.125.229.204]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C8B0750129A for ; Mon, 21 Sep 2026 18:31:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.229.204 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790015515; cv=none; b=Pxtggu1jYJNYNsycwwgI0c2ITFXR42B5vZL5phVZOw2N4GniJQOXrWVnKUDfT6oVH5cWT1yv/1O7COaMkIZC67NSHb8IOzOV0ECJ9m110stRxbz0OAqJDeEgO0TMJiZg1DmOhvm70ijLW1/1Y3aUuaxV0pqIKYKqy0VIdSHsh1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790015515; c=relaxed/simple; bh=W+X4H/UMTXCi1rpjpKYwefBmr26TJf9yG3HSNcI2DDc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LnqM/YFr8hVXDIe1bFqRORaKC8CeDOC5aZ4t81/KeOHxH+gkILmtHwT2kCzgChd+zy0jSKYbDTHqzHHLMq6bMxk/ZRHjSrIYRnBwgx0LDHRoCXfVW1jjtVq/ObDIIAU6+SVQsazM3aAhz8+sH21QU74uhtqfDnZbhXLoo2qLAhU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=qMGljpat; arc=none smtp.client-ip=74.125.229.204 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qMGljpat" Received: by mail-lf2-f12.google.com with SMTP id 2adb3069b0e04-5b5e4f1744eso2668661e87.1 for ; Mon, 21 Sep 2026 11:31:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1790015511; x=1790620311; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=IDFrmjcxCDMyDqDCFYCMrvNRJ2RlyneJJcA1pkODkaI=; b=qMGljpatAKfZCTPBX+4bG+AvK82e+UcD/INZgA8C18Jc72KzisWtOXfLrdAgYJzX+C BMbDlZzSnfG9gy7a0eAsacIycdp/whBzrmtcnIyuLp2Gjyt4b8usrkihbnzizOWF/ZQm 2FOqSrf82chFimrpsdtSqQMVtzw8YVHYJGmzshyXDScoZtIydiWpsUA2AivpLVt0Yb1l tnNkbhrJYs2hccbJeyrbK7ZyHNwo4z9gHokLVlM6kxtTwDG/nqK33trE3EH4eJqpyXbz BUeVEdsKm5F27P5k5ajM3ORAN6ava+D5mW9dFotShUcYqkL6cseIHuNE3nRH725bNC0l g53g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790015511; x=1790620311; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=IDFrmjcxCDMyDqDCFYCMrvNRJ2RlyneJJcA1pkODkaI=; b=ckhcRWYakSmlzBlmZYFdFdtvqxjRqxnl/938ZoIuhzDa+99nKMJuObfK88jPYWhMK2 6Glg42HolRKxlnEqDukHtrUYv7ss3VizzkJFjp5URyb1/z9nINmzh88QDlrShZUclNsR vl7bRLJKWZt9XKDZxQIBvlTeSEh/hzQUUPWOivkZHrYr2UyXgpu+scvSvSAuQi98atPm +phUuzFrRkB+RM6Rsx18SUAxK2YTuso1VExApLOVjC02CJonWej36xnZZKMKeTNsejWq 53bRZpaksVTV2fKTP7zTPK3GcFuwsSMpEYsqGbml/9OCroO8ERfxwiW0HYlyDUKGlnjD IsAg== X-Forwarded-Encrypted: i=1; AKwUvBxqsFYB37s4Lg+tDmakIql/5ytDM9ZY28G5IdKzYnCeTxJMzMMBJkApEa+QmipHxvHnoPGtYprktDimt2Y=@vger.kernel.org X-Gm-Message-State: AFuF++lRhTGzGJj1XQLx0cNPXMo8FIJKBN3up4a1dP/LMZ+qQwtEAopR ahIiWnNXZdrsjoVf/R2MMGzU85B+rbaJV4auOzHP4xPpi43CsGKNqoW68tB5wvg6 X-Gm-Gg: AYBFou2/ZhsjCjamuO53aalQjuiHhez6socW3mRWib4nXz9wLDYaF0HnehrVS9CxRWf NgRnzkw5wSRBAqMcsOsVnZkybeBSqjBKQOC6UFS9MNP8H1Oom2cv0UYBfsR9Wryt+KOXRLup3PY HLxJqjq3WKeamb/Rf1mE1JV24ObPl75A5V0Xt/aAoL7iYAkKP+IF5XvXu1sIyd+nrxu2hAVjEN4 NDx6cWdZL5y1PpI3CUu7zoTUTa1qJXxoZowJOT2Of/9ysdPe8qzk8Rip5oR11UFv2vsWgpjhgQA PB8Vn+kWy/lubcSAcd6OqMD8GktvhksWHzYqg1i940uT5IDVxPRigUrss2Cfyu98kwe8d3JWmlH bLyQpFcDPohyr0VtETef67g9Ubaszkfx59aqq+mYGDWAxx/AevOZJQYj3d3SN9KI69dAtY90NeP YEOImkwavJmz91SV/M15c1CpDU2ly4bjmsoLbU13FIzkb91oTiIzkTs31rYDOCDMGfvl/kYxHVI Q3TKiDa0ekQONb6nsUT5RQgh5HRBCg4H7O8Mcore3Yz24Lp5xD/Whxe6hzys6fnoFKWDg== X-Received: by 2002:ac2:4c4c:0:b0:5b6:183c:5c88 with SMTP id 2adb3069b0e04-5b8c1846df6mr3737251e87.38.1790015511240; Mon, 21 Sep 2026 11:31:51 -0700 (PDT) Received: from yantra.. (dsl-trebng21-58c187-236.dhcp.inet.fi. [88.193.135.236]) by smtp.gmail.com with ESMTPSA id 38308e7fff4ca-3a60761e5d6sm24260141fa.29.2026.09.21.11.31.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Sep 2026 11:31:50 -0700 (PDT) From: Rupesh Majhi To: Andy Shevchenko , Bill Wendling , David Lechner , Eddie James , Joel Stanley , Jonathan Cameron , Justin Stitt , Nathan Chancellor , Nick Desaulniers , =?UTF-8?q?Nuno=20S=C3=A1?= Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, llvm@lists.linux.dev, Rupesh Majhi Subject: [PATCH v8 09/10] iio: pressure: dps310: implement .hwfifo_flush_to_buffer() Date: Mon, 21 Sep 2026 21:31:31 +0300 Message-ID: <20260921183132.233136-10-zoone.rupert@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260921183132.233136-1-zoone.rupert@gmail.com> References: <20260921183132.233136-1-zoone.rupert@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Let userspace drain the FIFO on demand rather than only from the periodic drain. With a trigger attached the FIFO is not running, so there is nothing to flush and the hook returns 0. Hold the mode across the drain, so a concurrent buffer disable cannot free active_scan_mask while it runs. Assisted-by: LLM Signed-off-by: Rupesh Majhi --- drivers/iio/pressure/dps310.c | 36 ++++++++++++++++++++++++++++++++--- 1 file changed, 33 insertions(+), 3 deletions(-) diff --git a/drivers/iio/pressure/dps310.c b/drivers/iio/pressure/dps310.c index 974630eca547..59203df1ae35 100644 --- a/drivers/iio/pressure/dps310.c +++ b/drivers/iio/pressure/dps310.c @@ -1093,22 +1093,30 @@ static int dps310_fifo_push_held(struct dps310_data *data) /* * Read the batch out before compensating it, so a pressure entry pairs with - * the temperature preceding it rather than the last one in the batch. + * the temperature preceding it rather than the last one in the batch. Stop + * reading at max_scans rather than after it, since entries leave the hardware + * as they are read and any extra would have to be thrown away. max_scans of + * zero drains everything. * * Returns scans pushed. */ -static int dps310_fifo_drain(struct dps310_data *data) +static int dps310_fifo_drain(struct dps310_data *data, unsigned int max_scans) __must_hold(&data->lock) { bool pressure_enabled = test_bit(DPS310_SCAN_PRESSURE, data->iio->active_scan_mask); u8 kind[DPS310_FIFO_DEPTH]; s32 raw[DPS310_FIFO_DEPTH]; + unsigned int scans = 0; unsigned int pushed = 0; unsigned int cnt, i; + bool is_pressure; int rc; for (cnt = 0; cnt < DPS310_FIFO_DEPTH; cnt++) { + if (max_scans && scans >= max_scans) + break; + rc = dps310_fifo_read_entry(data, &raw[cnt]); if (rc < 0) return rc; @@ -1116,7 +1124,12 @@ static int dps310_fifo_drain(struct dps310_data *data) if (rc == DPS310_FIFO_EMPTY) break; + is_pressure = rc == DPS310_FIFO_PRESSURE; kind[cnt] = rc; + + /* Only the measurement that drives the scans counts */ + if (is_pressure == pressure_enabled) + scans++; } for (i = 0; i < cnt; i++) { @@ -1166,7 +1179,7 @@ static void dps310_fifo_work(struct work_struct *work) int rc; mutex_lock(&data->lock); - rc = dps310_fifo_drain(data); + rc = dps310_fifo_drain(data, 0); mutex_unlock(&data->lock); if (rc < 0) @@ -1201,6 +1214,22 @@ static int dps310_fifo_hold_alloc(struct dps310_data *data, int prs_rate, return 0; } +static int dps310_hwfifo_flush(struct iio_dev *iio, unsigned int count) +{ + struct dps310_data *data = iio_priv(iio); + + /* Holding the mode keeps active_scan_mask alive across the drain */ + IIO_DEV_GUARD_CURRENT_MODE(iio); + + /* A trigger drives the capture instead and leaves the FIFO empty */ + if (iio_device_get_current_mode(iio) != INDIO_BUFFER_SOFTWARE) + return 0; + + guard(mutex)(&data->lock); + + return dps310_fifo_drain(data, count); +} + static int dps310_hwfifo_set_watermark(struct iio_dev *iio, unsigned int val) { struct dps310_data *data = iio_priv(iio); @@ -1338,6 +1367,7 @@ static const struct iio_info dps310_info = { .read_raw = dps310_read_raw, .write_raw = dps310_write_raw, .hwfifo_set_watermark = dps310_hwfifo_set_watermark, + .hwfifo_flush_to_buffer = dps310_hwfifo_flush, }; static int dps310_probe(struct i2c_client *client) -- 2.43.0