linux-kernel - [PATCH v3 06/15] Bluetooth: hci_bcm: Simplify clk

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20181217040449.31437-7-wens@csie.org>
Date:   Mon, 17 Dec 2018 12:04:40 +0800
From:   Chen-Yu Tsai <wens@...e.org>
To:     Marcel Holtmann <marcel@...tmann.org>,
        Johan Hedberg <johan.hedberg@...il.com>,
        Rob Herring <robh+dt@...nel.org>,
        Mark Rutland <mark.rutland@....com>,
        Maxime Ripard <maxime.ripard@...tlin.com>
Cc:     Chen-Yu Tsai <wens@...e.org>,
        Loic Poulain <loic.poulain@...il.com>,
        linux-bluetooth@...r.kernel.org, devicetree@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Ondrej Jirman <megous@...ous.com>
Subject: [PATCH v3 06/15] Bluetooth: hci_bcm: Simplify clk_get error handling

The driver currently checks the clk pointer for an error condition, as
returned by clk_get, before every invocation of the clk consumer API.
This is redundant if the goal is simply to ignore the errors, thereby
making the clk optional. The clk consumer API already checks if the
pointer is NULL or not.

Simplify the code a bit by assigning NULL to the clk pointer if the
error condition is one we want to ignore, which is every error except
deferred probing.

Tested-by: Ondrej Jirman <megous@...ous.com>
Signed-off-by: Chen-Yu Tsai <wens@...e.org>
---
 drivers/bluetooth/hci_bcm.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 800132369134..ff73ecb8215f 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -214,7 +214,7 @@ static int bcm_gpio_set_power(struct bcm_device *dev, bool powered)
 {
 	int err;
 
-	if (powered && !IS_ERR(dev->clk) && !dev->clk_enabled) {
+	if (powered && !dev->clk_enabled) {
 		err = clk_prepare_enable(dev->clk);
 		if (err)
 			return err;
@@ -228,7 +228,7 @@ static int bcm_gpio_set_power(struct bcm_device *dev, bool powered)
 	if (err)
 		goto err_revert_shutdown;
 
-	if (!powered && !IS_ERR(dev->clk) && dev->clk_enabled)
+	if (!powered && dev->clk_enabled)
 		clk_disable_unprepare(dev->clk);
 
 	dev->clk_enabled = powered;
@@ -238,7 +238,7 @@ static int bcm_gpio_set_power(struct bcm_device *dev, bool powered)
 err_revert_shutdown:
 	dev->set_shutdown(dev, !powered);
 err_clk_disable:
-	if (powered && !IS_ERR(dev->clk) && !dev->clk_enabled)
+	if (powered && !dev->clk_enabled)
 		clk_disable_unprepare(dev->clk);
 	return err;
 }
@@ -911,6 +911,10 @@ static int bcm_get_resources(struct bcm_device *dev)
 	if (dev->clk == ERR_PTR(-EPROBE_DEFER))
 		return PTR_ERR(dev->clk);
 
+	/* Ignore all other errors as before */
+	if (IS_ERR(dev->clk))
+		dev->clk = NULL;
+
 	dev->device_wakeup = devm_gpiod_get_optional(dev->dev, "device-wakeup",
 						     GPIOD_OUT_LOW);
 	if (IS_ERR(dev->device_wakeup))
-- 
2.20.0