On Mon, Jun 7, 2021 at 2:39 PM Guoqing Chi <chi962464zy@xxxxxxx> wrote:
>
> From: Guoqing Chi <chiguoqing@xxxxxxxxxx>
>
> ff40: 00000000 95fffa74 00000000 e07b2198 00000000 00000007 81391000 e07b2198
> ff60: 00000007 81391000 81267834 81391000 0000015a 81200f00 00000006 00000006
> ff80: 00000000 81200514 00000000 80bfbd88 00000000 00000000 00000000 00000000
> ffa0: 00000000 80bfbd90 00000000 801010e8 00000000 00000000 00000000 00000000
> ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
> [<808f3228>] (inv_mpu_i2c_aux_setup) from [<808f1c18>] (inv_mpu_core_probe+0x638/0x878)
> [<808f1c18>] (inv_mpu_core_probe) from [<808f3100>] (inv_mpu_probe+0xe4/0x1f0)
> [<808f3100>] (inv_mpu_probe) from [<80801c88>] (i2c_device_probe+0x238/0x26c)
> [<80801c88>] (i2c_device_probe) from [<8063520c>] (really_probe+0x218/0x348)
> [<8063520c>] (really_probe) from [<806354b4>] (driver_probe_device+0x60/0x164)
> [<806354b4>] (driver_probe_device) from [<80635760>] (device_driver_attach+0x58/0x60)
> [<80635760>] (device_driver_attach) from [<806357e8>] (__driver_attach+0x80/0xbc)
> [<806357e8>] (__driver_attach) from [<80633560>] (bus_for_each_dev+0x74/0xb4)
> [<80633560>] (bus_for_each_dev) from [<80634548>] (bus_add_driver+0x160/0x1e4)
> [<80634548>] (bus_add_driver) from [<80636018>] (driver_register+0x7c/0x114)
> [<80636018>] (driver_register) from [<80801644>] (i2c_register_driver+0x3c/0x80)
> [<80801644>] (i2c_register_driver) from [<8010277c>] (do_one_initcall+0x54/0x1b8)
> [<8010277c>] (do_one_initcall) from [<81200f00>] (kernel_init_freeable+0x144/0x1e0)
> [<81200f00>] (kernel_init_freeable) from [<80bfbd90>] (kernel_init+0x8/0x10c)
> [<80bfbd90>] (kernel_init) from [<801010e8>] (ret_from_fork+0x14/0x2c)
>
> If we do not use aux or forget config child node at dts,it will be in dump.
>
> Signed-off-by: Guoqing Chi <chiguoqing@xxxxxxxxxx>
> ---
> drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
> index 95f16951c8f4..b0f45042a25f 100644
> --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
> +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_i2c.c
> @@ -77,11 +77,14 @@ static int inv_mpu_i2c_aux_setup(struct iio_dev *indio_dev)
> }
>
> /* enable i2c bypass when using i2c auxiliary bus */
> - if (inv_mpu_i2c_aux_bus(dev)) {
> + if (dev != NULL && inv_mpu_i2c_aux_bus(dev)) {
One point is that this solves the issue for the I2C variant, but
doesn't seem to handle the SPI variant of the driver/device.
So, maybe this should be checked for NULL in inv_mpu_core_probe().
But, the 'dev' reference comes from this assignment 'struct device
*dev = indio_dev->dev.parent;', which looks impossible given that the
IIO device-object was created with devm_iio_device_alloc().
So, 'indio_dev->dev.parent' can't be NULL, as far as I can tell.
On what version of the kernel has this been seen?
> ret = regmap_write(st->map, st->reg->int_pin_cfg,
> st->irq_mask | INV_MPU6050_BIT_BYPASS_EN);
> if (ret)
> return ret;
> + } else {
> + dev_err(&indio_dev->dev, "Failed to enable i2c bypass.\n");
> + return -EFAULT;
> }
>
> return 0;
> --
> 2.17.1
>
