From: Linus Walleij Date: Mon, 3 Nov 2025 09:36:18 +0000 (+0100) Subject: iio: accel: bmc150: Fix irq assumption regression X-Git-Tag: v6.18~9^2~2^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=3aa385a9c75c09b59dcab2ff76423439d23673ab;p=thirdparty%2Flinux.git iio: accel: bmc150: Fix irq assumption regression The code in bmc150-accel-core.c unconditionally calls bmc150_accel_set_interrupt() in the iio_buffer_setup_ops, such as on the runtime PM resume path giving a kernel splat like this if the device has no interrupts: Unable to handle kernel NULL pointer dereference at virtual address 00000001 when read PC is at bmc150_accel_set_interrupt+0x98/0x194 LR is at __pm_runtime_resume+0x5c/0x64 (...) Call trace: bmc150_accel_set_interrupt from bmc150_accel_buffer_postenable+0x40/0x108 bmc150_accel_buffer_postenable from __iio_update_buffers+0xbe0/0xcbc __iio_update_buffers from enable_store+0x84/0xc8 enable_store from kernfs_fop_write_iter+0x154/0x1b4 This bug seems to have been in the driver since the beginning, but it only manifests recently, I do not know why. Store the IRQ number in the state struct, as this is a common pattern in other drivers, then use this to determine if we have IRQ support or not. Cc: stable@vger.kernel.org Signed-off-by: Linus Walleij Reviewed-by: Andy Shevchenko Reviewed-by: Nuno Sá Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/accel/bmc150-accel-core.c b/drivers/iio/accel/bmc150-accel-core.c index 3c5d1560b163d..42ccf0316ce59 100644 --- a/drivers/iio/accel/bmc150-accel-core.c +++ b/drivers/iio/accel/bmc150-accel-core.c @@ -523,6 +523,10 @@ static int bmc150_accel_set_interrupt(struct bmc150_accel_data *data, int i, const struct bmc150_accel_interrupt_info *info = intr->info; int ret; + /* We do not always have an IRQ */ + if (data->irq <= 0) + return 0; + if (state) { if (atomic_inc_return(&intr->users) > 1) return 0; @@ -1696,6 +1700,7 @@ int bmc150_accel_core_probe(struct device *dev, struct regmap *regmap, int irq, } if (irq > 0) { + data->irq = irq; ret = devm_request_threaded_irq(dev, irq, bmc150_accel_irq_handler, bmc150_accel_irq_thread_handler, diff --git a/drivers/iio/accel/bmc150-accel.h b/drivers/iio/accel/bmc150-accel.h index 7a7baf52e5955..e8f26198359f6 100644 --- a/drivers/iio/accel/bmc150-accel.h +++ b/drivers/iio/accel/bmc150-accel.h @@ -58,6 +58,7 @@ enum bmc150_accel_trigger_id { struct bmc150_accel_data { struct regmap *regmap; + int irq; struct regulator_bulk_data regulators[2]; struct bmc150_accel_interrupt interrupts[BMC150_ACCEL_INTERRUPTS]; struct bmc150_accel_trigger triggers[BMC150_ACCEL_TRIGGERS];