From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A09483905FD for ; Thu, 27 Aug 2026 04:40:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787805613; cv=none; b=Rt0xkrfnUWjTBPuX6SrbFTowgD9/LhQQ/U7mWsb1pNdQMbaxXqlYlI4GMh/rDhCoKGyaEYXapOoYoXsAOM7OQd38GKxqqNgoCxjEDE0chv5cLZEa+fDayRyr9+w8p1MOVTfZ/5Hi3GQ4qyhDEAZ+nn1nr42buem1ay9Vl3fpOgU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787805613; c=relaxed/simple; bh=nq7rfwIiOi+70cNPttBUAcz7rBFHP3AgkKsO95AGi6E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=KRJYZ+uSudm/LlegoRFzIiBww8uuK0Bx1Rzh3ih56S7tTBMhzc+FVuH9JQLqLrJBp6E4lqgEbnGhh8oHLSMig6XXGImeQHFhb8JxGUISMfeiW/PG/otEcEa9x4GBPUAG+aBlUT3dacTi7Fhkp+xKdEDGwv/sBLHXPmWvallavfM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PD9Kqw48; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PD9Kqw48" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7A6F1F00A3A; Thu, 27 Aug 2026 04:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787805612; bh=5RaYilTHCObGUjGVhECyCYSW1RIHrpe6PLY1xGi76sM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=PD9Kqw48w33pcjkBnVv8F/NSADMlMkUhFMUvPJklYh6E60kcJMcg9MGW4JaVHLl5j VC2vAxJVa6igFii02TdoGY3ZYbP+gSgDOe1AWra8YnGAhsy3A5acg/J7GFcXyoya41 W7yMdDy2XB6Wu2A/F9qRrGar5foOXJ/BmhrENgiGUnhLpvZvBznH+z8teduLWyfate L6ZGG174Dzsn1jhHh0kq1tDJU2tcj9jS4R1n0kq54zWgmfcT6HTCE6kwKq3F5bLXHL +S4t4JvcpbGbdar99WpW6k+ZmwO7Sc827/Jb8vbr00y/HZtEjwn+SXIi4dDH0m2UBT m+bQgZ7uN5tjw== From: Sasha Levin To: stable@vger.kernel.org Cc: Michael Zaidman , Enrik Berkhan , Jiri Kosina , Sasha Levin Subject: [PATCH 5.15.y 5/8] HID: ft260: wake up device from power saving mode Date: Thu, 27 Aug 2026 00:40:03 -0400 Message-ID: <20260827044007.3635916-5-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260827044007.3635916-1-sashal@kernel.org> References: <2026082538-obstacle-cogwheel-cfc1@gregkh> <20260827044007.3635916-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Michael Zaidman [ Upstream commit 4b3da6853a619a952e8caf2e8393264dd42ffa27 ] The FT260 can enter a power saving mode after being idle for longer than 5 seconds. When being woken up from power saving mode by an I2C write request, a possible NACK is not correctly reported by the controller. As a workaround, the driver will issue an I2C status report two times in ft260_xfer_status() after the chip has been idle for more than 5s. Co-developed-by: Enrik Berkhan Signed-off-by: Enrik Berkhan Signed-off-by: Michael Zaidman Signed-off-by: Jiri Kosina Stable-dep-of: bf3e39df3a39 ("HID: ft260: fix stack-use-after-return write in I2C read race") Signed-off-by: Sasha Levin --- drivers/hid/hid-ft260.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c index 6f6bfd305e229..d3c33c1b130c9 100644 --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -31,6 +31,8 @@ MODULE_PARM_DESC(debug, "Toggle FT260 debugging messages"); #define FT260_REPORT_MAX_LENGTH (64) #define FT260_I2C_DATA_REPORT_ID(len) (FT260_I2C_REPORT_MIN + (len - 1) / 4) +#define FT260_WAKEUP_NEEDED_AFTER_MS (4800) /* 5s minus 200ms margin */ + /* * The ft260 input report format defines 62 bytes for the data payload, but * when requested 62 bytes, the controller returns 60 and 2 in separate input @@ -237,6 +239,7 @@ struct ft260_device { struct completion wait; struct mutex lock; u8 write_buf[FT260_REPORT_MAX_LENGTH]; + unsigned long need_wakeup_at; u8 *read_buf; u16 read_idx; u16 read_len; @@ -306,6 +309,20 @@ static int ft260_xfer_status(struct ft260_device *dev) struct ft260_get_i2c_status_report report; int ret; + if (time_is_before_jiffies(dev->need_wakeup_at)) { + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, + (u8 *)&report, sizeof(report)); + if (unlikely(ret < 0)) { + hid_err(hdev, "failed to retrieve status: %d, no wakeup\n", + ret); + } else { + dev->need_wakeup_at = jiffies + + msecs_to_jiffies(FT260_WAKEUP_NEEDED_AFTER_MS); + ft260_dbg("bus_status %#02x, wakeup\n", + report.bus_status); + } + } + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, (u8 *)&report, sizeof(report)); if (unlikely(ret < 0)) { -- 2.53.0