linux-kernel - [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

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Message-Id: <20200630133345.2232932-11-lee.jones@linaro.org>
Date:   Tue, 30 Jun 2020 14:33:45 +0100
From:   Lee Jones <lee.jones@...aro.org>
To:     linus.walleij@...aro.org, bgolaszewski@...libre.com
Cc:     linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-gpio@...r.kernel.org, Lee Jones <lee.jones@...aro.org>,
        Asmaa Mnebhi <Asmaa@...lanox.com>
Subject: [PATCH 10/10] gpio: gpio-mlxbf2.c: Provide __releases() annotation to stop confusing Sparse

Sparse cannot peer into other functions to see when and if locks are
acquired and released, thus it simply warns that a 'context imbalance'
is detected instead.  Let's be kind to Sparse and let it know that
this behaviour is intentional.

 drivers/gpio/gpio-mlxbf2.c:125:12: warning: context imbalance in 'mlxbf2_gpio_lock_acquire' - different lock contexts for basic block
 drivers/gpio/gpio-mlxbf2.c:151:13: warning: context imbalance in 'mlxbf2_gpio_lock_release' - unexpected unlock

Cc: Asmaa Mnebhi <Asmaa@...lanox.com>
Signed-off-by: Lee Jones <lee.jones@...aro.org>
---
 drivers/gpio/gpio-mlxbf2.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 861a8d0a84be0..befa5e1099439 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -149,6 +149,8 @@ static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
  * Release the YU arm_gpio_lock after changing the direction mode.
  */
 static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
+	__releases(&gs->gc.bgpio_lock)
+	__releases(yu_arm_gpio_lock_param.lock)
 {
 	writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
 	spin_unlock(&gs->gc.bgpio_lock);
-- 
2.25.1