linux-kernel - [PATCH 5/6] hid: mcp2200: use new line value setter callbacks

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Message-Id: <20250423-gpiochip-set-rv-hid-v1-5-2e6762b582f6@linaro.org>
Date: Wed, 23 Apr 2025 10:55:43 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Jiri Kosina <jikos@...nel.org>, Benjamin Tissoires <bentiss@...nel.org>, 
 Linus Walleij <linus.walleij@...aro.org>, 
 Bartosz Golaszewski <brgl@...ev.pl>, Rishi Gupta <gupt21@...il.com>
Cc: linux-input@...r.kernel.org, linux-kernel@...r.kernel.org, 
 linux-gpio@...r.kernel.org, linux-i2c@...r.kernel.org, 
 Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH 5/6] hid: mcp2200: use new line value setter callbacks

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

struct gpio_chip now has callbacks for setting line values that return
an integer, allowing to indicate failures. Convert the driver to using
them.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/hid/hid-mcp2200.c | 23 ++++++++++++++---------
 1 file changed, 14 insertions(+), 9 deletions(-)

diff --git a/drivers/hid/hid-mcp2200.c b/drivers/hid/hid-mcp2200.c
index bf57f7f6caa0..e6ea0a2140eb 100644
--- a/drivers/hid/hid-mcp2200.c
+++ b/drivers/hid/hid-mcp2200.c
@@ -127,8 +127,8 @@ static int mcp_cmd_read_all(struct mcp2200 *mcp)
 	return mcp->status;
 }
 
-static void mcp_set_multiple(struct gpio_chip *gc, unsigned long *mask,
-			     unsigned long *bits)
+static int mcp_set_multiple(struct gpio_chip *gc, unsigned long *mask,
+			    unsigned long *bits)
 {
 	struct mcp2200 *mcp = gpiochip_get_data(gc);
 	u8 value;
@@ -150,16 +150,20 @@ static void mcp_set_multiple(struct gpio_chip *gc, unsigned long *mask,
 
 	if (status == sizeof(struct mcp_set_clear_outputs))
 		mcp->gpio_val = value;
+	else
+		status = -EIO;
 
 	mutex_unlock(&mcp->lock);
+
+	return status;
 }
 
-static void mcp_set(struct gpio_chip *gc, unsigned int gpio_nr, int value)
+static int mcp_set(struct gpio_chip *gc, unsigned int gpio_nr, int value)
 {
 	unsigned long mask = 1 << gpio_nr;
 	unsigned long bmap_value = value << gpio_nr;
 
-	mcp_set_multiple(gc, &mask, &bmap_value);
+	return mcp_set_multiple(gc, &mask, &bmap_value);
 }
 
 static int mcp_get_multiple(struct gpio_chip *gc, unsigned long *mask,
@@ -263,9 +267,10 @@ static int mcp_direction_output(struct gpio_chip *gc, unsigned int gpio_nr,
 	bmap_value = value << gpio_nr;
 
 	ret = mcp_set_direction(gc, gpio_nr, MCP2200_DIR_OUT);
-	if (!ret)
-		mcp_set_multiple(gc, &mask, &bmap_value);
-	return ret;
+	if (ret)
+		return ret;
+
+	return mcp_set_multiple(gc, &mask, &bmap_value);
 }
 
 static const struct gpio_chip template_chip = {
@@ -274,8 +279,8 @@ static const struct gpio_chip template_chip = {
 	.get_direction		= mcp_get_direction,
 	.direction_input	= mcp_direction_input,
 	.direction_output	= mcp_direction_output,
-	.set			= mcp_set,
-	.set_multiple		= mcp_set_multiple,
+	.set_rv			= mcp_set,
+	.set_multiple_rv	= mcp_set_multiple,
 	.get			= mcp_get,
 	.get_multiple		= mcp_get_multiple,
 	.base			= -1,

-- 
2.45.2