linux-kernel - [PATCH v2 3/4] pwm: Mark free pwm IDs as used in alloc

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Date:   Thu, 17 Nov 2022 22:11:42 +0100
From:   Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>
To:     Thierry Reding <thierry.reding@...il.com>
Cc:     linux-pwm@...r.kernel.org,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        linux-kernel@...r.kernel.org, kernel@...gutronix.de
Subject: [PATCH v2 3/4] pwm: Mark free pwm IDs as used in alloc_pwms()

alloc_pwms() only identified a free range of IDs and this range was marked
as used only later by pwmchip_add(). Instead let alloc_pwms() already do
the marking (which makes the function actually allocating the range and so
justifies the function name). This way access to the allocated_pwms
bitfield is limited to two functions only.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
---
 drivers/pwm/core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 2338119a09d8..b43b24bd3c9f 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -51,6 +51,8 @@ static int alloc_pwms(unsigned int count)
 	if (start + count > MAX_PWMS)
 		return -ENOSPC;
 
+	bitmap_set(allocated_pwms, start, count);
+
 	return start;
 }
 
@@ -297,8 +299,6 @@ int pwmchip_add(struct pwm_chip *chip)
 		radix_tree_insert(&pwm_tree, pwm->pwm, pwm);
 	}
 
-	bitmap_set(allocated_pwms, chip->base, chip->npwm);
-
 	INIT_LIST_HEAD(&chip->list);
 	list_add(&chip->list, &pwm_chips);
 
-- 
2.38.1