On Mon, Mar 19, 2018 at 03:48:50PM +0000, Sasha Levin wrote:
From: Lukas Wunner lukas@wunner.de
[ Upstream commit 3e81a4ca51a1172253078ca7abd6a91040b8fcf4 ]
Unfortunately this commit had to be fixed up with ab2f336cb7e6 ("Bluetooth: hci_bcm: Make shutdown and device wake GPIO optional") by Stefan Wahren (+cc).
Please be sure to apply that one on top. Thanks!
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 Signed-off-by: Sasha Levin alexander.levin@microsoft.com
drivers/bluetooth/hci_bcm.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-)
diff --git a/drivers/bluetooth/hci_bcm.c b/drivers/bluetooth/hci_bcm.c index 707c2d1b84c7..b8eeac4e6f35 100644 --- a/drivers/bluetooth/hci_bcm.c +++ b/drivers/bluetooth/hci_bcm.c @@ -577,11 +577,9 @@ 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; } @@ -592,11 +590,9 @@ 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) { @@ -779,14 +775,12 @@ 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",GPIOD_OUT_LOW);
- dev->device_wakeup = devm_gpiod_get(dev->dev, "device-wakeup",
GPIOD_OUT_LOW);
- dev->shutdown = devm_gpiod_get_optional(dev->dev, "shutdown",
GPIOD_OUT_LOW);
- dev->shutdown = devm_gpiod_get(dev->dev, "shutdown", GPIOD_OUT_LOW); if (IS_ERR(dev->shutdown)) return PTR_ERR(dev->shutdown);
2.14.1