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 5CD04361DCB for ; Wed, 22 Jul 2026 15:04:31 +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=1784732672; cv=none; b=k9Qtw2ZFfGK7PQ/6ny3k1w3fuUMeAkD900ptS3ESFfBkop4FIABt34bExWxAWFUY0Czxn2G7ahvODKl3nAFR01KvXxEhXx+vi3mNpEJ290/J9JSRS+a2ojh9/A52CGLIMC90TtG2mrzmgNC9eCouSITHdpO/UKU7hDtQvPdyrSs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784732672; c=relaxed/simple; bh=IFSWDc3LjOPTWYAPQNs98ixuyaKl4CCl24Ci2P5i3EU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sHIPO3e00gH6qOht1DjtV18LwzFA4qibLisOSGQcXo+F1YSOw/QyQZMLHG33qDm8ExZ4LDda5bWA1d3uasxOGHPC/jW4b++aSI4xiRIogKPf0GTcrGMh0SQhef3LI5/r4q49NNSF1Gig71bdKG1Yy/NY3joASecAYOxSRyXk0C8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=I5Fmvd4A; 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="I5Fmvd4A" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3CD301F00A3D; Wed, 22 Jul 2026 15:04:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784732671; bh=722Va9xnpxJRA6NyIGySj0OrNwlgYdYxPOu4S73spxQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=I5Fmvd4A+g9HoDJiKZ8uXebOuVMzLtihEho09MF5sqDWpGZb+c1OxmK+ViKD7ci/F 8FF4p9/M8iUTWcG6KVag1sWiA4G3aQym/ElKrF5zFlyvWgx/B1MxN73mWip0Qz5YqI UfZY7OKjwZ8x90NyQ0aN15dOgmt6G6ibqOdVdU0DE4Fle8byS8yOldXCFNpsCR1xKy Nw49vYzrjYPostLAMH7olDSxjAbPs99FGCfUicpwmkpsNdksHFgRPSm86EM2BpdiaH XEQIX3wxyoc4TXixuAmZ3+VtMJv9RVROMPK+jxtb3ENBW2yqlNRqqiOiBMhI2mhqP+ bBxeD4Ro8kpOw== From: Sasha Levin To: stable@vger.kernel.org Cc: Tapio Reijonen , stable , Linus Walleij , Bartosz Golaszewski , Hugo Villeneuve , Greg Kroah-Hartman , Sasha Levin Subject: [PATCH 5.15.y 2/2] serial: max310x: implement gpio_chip::get_direction() Date: Wed, 22 Jul 2026 11:04:27 -0400 Message-ID: <20260722150427.1659292-2-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260722150427.1659292-1-sashal@kernel.org> References: <2026072034-pointing-culminate-408c@gregkh> <20260722150427.1659292-1-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: Tapio Reijonen [ Upstream commit a483b1a91b33b7533280e7c3efd2bc1275caef18 ] It's strongly recommended for GPIO drivers to always implement the .get_direction() callback - even when the direction is tracked in software. The GPIO core emits a warning when the callback is missing and a user reads the direction of a line, e.g. via /sys/kernel/debug/gpio. The MAX310X keeps the GPIO direction in the GPIOCFG register (a set bit selects output), which the existing direction_input/output callbacks already program, so the current direction can be read back directly. Fixes: f65444187a66 ("serial: New serial driver MAX310X") Cc: stable Signed-off-by: Tapio Reijonen Reviewed-by: Linus Walleij Reviewed-by: Bartosz Golaszewski Reviewed-by: Hugo Villeneuve Link: https://patch.msgid.link/20260615-b4-serial-max310x-gpio-get-direction-v2-1-4704ba2b181a@vaisala.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/max310x.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c index bfce8ad9a88117..8e7aa24da23277 100644 --- a/drivers/tty/serial/max310x.c +++ b/drivers/tty/serial/max310x.c @@ -1213,6 +1213,17 @@ static void max310x_gpio_set(struct gpio_chip *chip, unsigned int offset, int va value ? 1 << (offset % 4) : 0); } +static int max310x_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) +{ + struct max310x_port *s = gpiochip_get_data(chip); + struct uart_port *port = &s->p[offset / 4].port; + unsigned int val; + + val = max310x_port_read(port, MAX310X_GPIOCFG_REG); + + return val & BIT(offset % 4) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN; +} + static int max310x_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) { struct max310x_port *s = gpiochip_get_data(chip); @@ -1414,6 +1425,7 @@ static int max310x_probe(struct device *dev, const struct max310x_devtype *devty s->gpio.owner = THIS_MODULE; s->gpio.parent = dev; s->gpio.label = devtype->name; + s->gpio.get_direction = max310x_gpio_get_direction; s->gpio.direction_input = max310x_gpio_direction_input; s->gpio.get = max310x_gpio_get; s->gpio.direction_output= max310x_gpio_direction_output; -- 2.53.0