From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:42368 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751505AbeDIJgp (ORCPT ); Mon, 9 Apr 2018 05:36:45 -0400 Subject: Patch "Bluetooth: hci_bcm: Mandate presence of shutdown and device wake GPIO" has been added to the 4.15-stable tree To: lukas@wunner.de, alexander.levin@microsoft.com, andriy.shevchenko@linux.intel.com, frederic.danis.oss@gmail.com, gregkh@linuxfoundation.org, hdegoede@redhat.com, linus.walleij@linaro.org, loic.poulain@linaro.org, marcel@holtmann.org, u.kleine-koenig@pengutronix.de Cc: , From: Date: Mon, 09 Apr 2018 11:36:08 +0200 Message-ID: <152326656861254@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled Bluetooth: hci_bcm: Mandate presence of shutdown and device wake GPIO to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: bluetooth-hci_bcm-mandate-presence-of-shutdown-and-device-wake-gpio.patch and it can be found in the queue-4.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Mon Apr 9 10:16:32 CEST 2018 From: Lukas Wunner Date: Wed, 10 Jan 2018 16:32:10 +0100 Subject: Bluetooth: hci_bcm: Mandate presence of shutdown and device wake GPIO From: Lukas Wunner [ Upstream commit 3e81a4ca51a1172253078ca7abd6a91040b8fcf4 ] 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 Cc: Loic Poulain Cc: Hans de Goede Cc: Uwe Kleine-König Cc: Linus Walleij Reviewed-by: Andy Shevchenko Signed-off-by: Lukas Wunner Signed-off-by: Marcel Holtmann Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/bluetooth/hci_bcm.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-) --- a/drivers/bluetooth/hci_bcm.c +++ b/drivers/bluetooth/hci_bcm.c @@ -577,11 +577,9 @@ static int bcm_suspend_device(struct 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 devi 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_ 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); if (IS_ERR(dev->device_wakeup)) return PTR_ERR(dev->device_wakeup); - 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); Patches currently in stable-queue which might be from lukas@wunner.de are queue-4.15/bluetooth-hci_bcm-mandate-presence-of-shutdown-and-device-wake-gpio.patch queue-4.15/bluetooth-hci_bcm-validate-irq-before-using-it.patch