On 1 February 2017 05:50:12 GMT+00:00, Peter Rosin <peda@xxxxxxxxxx> wrote: >On 2017-02-01 01:42, Ken.Lin wrote: >> >> >>> -----Original Message----- >>> From: Peter Rosin [mailto:peda@xxxxxxxxxx] >>> Sent: Tuesday, January 31, 2017 1:10 PM >>> To: Ken.Lin; jic23@xxxxxxxxxx >>> Cc: knaack.h@xxxxxx; pmeerw@xxxxxxxxxx; linux-iio@xxxxxxxxxxxxxxx; >linux- >>> kernel@xxxxxxxxxxxxxxx; Akshay Bhat; Peter.Stretz; Peter.Chiang >>> Subject: Re: kernel 4.10-rcx iio helper question >>> >>> On 2017-01-31 19:19, Ken.Lin wrote: >>>> Hi, >>>> >>>> I find the latest kernel introduces new iio sys attributes. >>>> https://patchwork.kernel.org/patch/9391771/ >>>> https://patchwork.kernel.org/patch/9391259/ >>>> >>>> Is there anyone has some ideas about how the new iio sys attribute >- >>> in_pressure_scale_available works? >>>> I'm not sure if it's the regression issue or it's just the usage >issue or something >>> when I tried to read in_pressure_scale_available attribute. >>> >>>> # cat /sys/bus/iio/devices/iio\:device1/in_pressure_scale_available >>>> Segmentation fault >>> >>> What driver is providing iio:device1? >>> >>>> [ 3785.077014] Unable to handle kernel NULL pointer dereference at >>>> virtual address 00000000 [ 3785.085138] pgd = ecc3c000 [ >3785.087929] >>>> [00000000] *pgd=87f91831 [ 3785.091563] Internal error: Oops: >80000007 >>>> [#1] SMP ARM [ 3785.096806] Modules linked in: >>>> [ 3785.099892] CPU: 1 PID: 1051 Comm: cat Not tainted >>>> 4.10.0-rc5-00009-gffd8858-dirty #3 >>> >>> Looks like you have a couple of local changes? What are those? >>> >> >> I didn't make any changes to the iio drivers locally and MPL3115A2 >pressure/temperature sensor driver (drivers/iio/pressure/mpl3115.c) is >the driver which provides iio:device1. >> >>> My WAG is that you added the IIO_CHAN_INFO_SCALE bit to one of the >>> .info_mask_*_available fields in the channel spec but failed to >provide a >>> .read_avail operation in the driver. Am I close? >>> >> >> I could read iio:device0/in_accel_scale and >device0/in_accel_available, which are provided by NXP 3-axis >accelerometers driver (drivers/iio/accel/mma8452.c). >> The attribute iio:/device1/in_pressure_scale is missing unless I >reverted the commits. >> https://patchwork.kernel.org/patch/9391771/ >> https://patchwork.kernel.org/patch/9391259/ > >Whoops, sorry for suggesting you did something wrong... > >Can you try this patch? Gah. My eyes passed straight over that. Thanks Ken, nice regression report and thank peda for the fix. Phew, single driver bug rather than a general regression! Jonathan > >Cheers, >peda > >diff --git a/drivers/iio/pressure/mpl115.c >b/drivers/iio/pressure/mpl115.c >index 73f2f0c46e62..8f2bce213248 100644 >--- a/drivers/iio/pressure/mpl115.c >+++ b/drivers/iio/pressure/mpl115.c >@@ -137,6 +137,7 @@ static const struct iio_chan_spec mpl115_channels[] >= { > { > .type = IIO_TEMP, > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), >+ .info_mask_shared_by_type = > BIT(IIO_CHAN_INFO_OFFSET) | BIT(IIO_CHAN_INFO_SCALE), > }, > }; >diff --git a/drivers/iio/pressure/mpl3115.c >b/drivers/iio/pressure/mpl3115.c >index cc3f84139157..525644a7442d 100644 >--- a/drivers/iio/pressure/mpl3115.c >+++ b/drivers/iio/pressure/mpl3115.c >@@ -190,7 +190,7 @@ static const struct iio_chan_spec >mpl3115_channels[] = { > { > .type = IIO_PRESSURE, > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), >- BIT(IIO_CHAN_INFO_SCALE), >+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > .scan_index = 0, > .scan_type = { > .sign = 'u', >@@ -203,7 +203,7 @@ static const struct iio_chan_spec >mpl3115_channels[] = { > { > .type = IIO_TEMP, > .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), >- BIT(IIO_CHAN_INFO_SCALE), >+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), > .scan_index = 1, > .scan_type = { > .sign = 's', -- Sent from my Android device with K-9 Mail. Please excuse my brevity. -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
