path: root/drivers/bluetooth
diff options
authorLukas Wunner <lukas@wunner.de>2018-01-10 16:32:10 +0100
committerMarcel Holtmann <marcel@holtmann.org>2018-01-10 19:00:12 +0100
commit3e81a4ca51a1172253078ca7abd6a91040b8fcf4 (patch)
treefe24117f1ebfee95cc0b1aa3a1c68be1a406c6af /drivers/bluetooth
parent61f5acea8737d9b717fcc22bb6679924f3c82b98 (diff)
Bluetooth: hci_bcm: Mandate presence of shutdown and device wake GPIO
Commit 0395ffc1ee05 ("Bluetooth: hci_bcm: Add PM for BCM devices") amended this driver to request a shutdown and device wake GPIO on probe, but mandated that only one of them need to be present: /* Make sure at-least one of the GPIO is defined and that * a name is specified for this instance */ if ((!dev->device_wakeup && !dev->shutdown) || !dev->name) { dev_err(&pdev->dev, "invalid platform data\n"); return -EINVAL; } However the same commit added a call to bcm_gpio_set_power() to the ->probe hook, which unconditionally accesses *both* GPIOs. Luckily, the resulting NULL pointer deref was never reported, suggesting there's no machine where either GPIO is missing. Commit 8a92056837fd ("Bluetooth: hci_bcm: Add (runtime)pm support to the serdev driver") removed the check whether at least one of the GPIOs is present without specifying a reason. Because commit 62aaefa7d038 ("Bluetooth: hci_bcm: improve use of gpios API") refactored the driver to use devm_gpiod_get_optional() instead of devm_gpiod_get(), one is now tempted to believe that the driver doesn't require *any* of the two GPIOs. Which is wrong, the driver still requires both GPIOs to avoid a NULL pointer deref. To this end, establish the status quo ante and request the GPIOs with devm_gpiod_get() again. Bail out of ->probe if either of them is missing. Oddly enough, whereas bcm_gpio_set_power() accesses the device wake pin unconditionally, bcm_suspend_device() and bcm_resume_device() do check for its presence before accessing it. Those checks are superfluous, so remove them. Cc: Frédéric Danis <frederic.danis.oss@gmail.com> Cc: Loic Poulain <loic.poulain@linaro.org> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'drivers/bluetooth')
1 files changed, 9 insertions, 15 deletions
diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c
index 1fc604a0d870..7d059b35c63a 100644
--- a/drivers/bluetooth/hci_bcm.c
+++ b/drivers/bluetooth/hci_bcm.c
@@ -572,11 +572,9 @@ static int bcm_suspend_device(struct device *dev)
/* Suspend the device */
- if (bdev->device_wakeup) {
- gpiod_set_value(bdev->device_wakeup, false);
- bt_dev_dbg(bdev, "suspend, delaying 15 ms");
- mdelay(15);
- }
+ gpiod_set_value(bdev->device_wakeup, false);
+ bt_dev_dbg(bdev, "suspend, delaying 15 ms");
+ mdelay(15);
return 0;
@@ -587,11 +585,9 @@ static int bcm_resume_device(struct device *dev)
bt_dev_dbg(bdev, "");
- if (bdev->device_wakeup) {
- gpiod_set_value(bdev->device_wakeup, true);
- bt_dev_dbg(bdev, "resume, delaying 15 ms");
- mdelay(15);
- }
+ gpiod_set_value(bdev->device_wakeup, true);
+ bt_dev_dbg(bdev, "resume, delaying 15 ms");
+ mdelay(15);
/* When this executes, the device has woken up already */
if (bdev->is_suspended && bdev->hu) {
@@ -774,14 +770,12 @@ static int bcm_get_resources(struct bcm_device *dev)
dev->clk = devm_clk_get(dev->dev, NULL);
- dev->device_wakeup = devm_gpiod_get_optional(dev->dev,
- "device-wakeup",
+ dev->device_wakeup = devm_gpiod_get(dev->dev, "device-wakeup",
if (IS_ERR(dev->device_wakeup))
return PTR_ERR(dev->device_wakeup);
- dev->shutdown = devm_gpiod_get_optional(dev->dev, "shutdown",
+ dev->shutdown = devm_gpiod_get(dev->dev, "shutdown", GPIOD_OUT_LOW);
if (IS_ERR(dev->shutdown))
return PTR_ERR(dev->shutdown);

Privacy Policy