Hi Guenter,
> On Mon, Dec 10, 2012 at 09:51:35AM -0500, Gabriel L. Somlo wrote:
> > The AppleSMC contains two char[32] keys, OSK0 and OSK1, which are not
> > reported in the key count and index by default. These keys are used by
> > the OS X boot sequence, and normally don't matter when running Linux.
> >
> > This patch creates a sysfs entry which reports the value of these keys
> > as an ASCII string, to help emulators (such as QEMU) load OS X when
> > running on genuine Apple hardware.
> >
> > Signed-off-by: Gabriel L. Somlo <somlo@xxxxxxx>
> > ---
> >
> > For extra context: To boot OS X as a guest, QEMU must (among others)
> > emulate the AppleSMC. To boot successfully, OS X insists on querying
> > the (emulated) SMC for the value of OSK0 and OSK1. Currently, these
> > values must be supplied on the QEMU command line as
> >
> > -device applesmc,osk="...concatenated values of OSK0 and OSK1..."
> >
> > With the availability of /sys/devices/platform/applesmc.768/osk, the
> > emulated QEMU AppleSMC could acquire this string directly from the
> > (Apple-manufactured) host machine.
> >
> Hmm ... this is a non-hwmon attribute which doesn't really belong into hwmon
> in the first place ... like several other attributes in the same driver.
>
> So I'll leave it up to the maintainer to decide if we should accept it. Henrik ?
Indeed, the reaons against this patch are too many. I was just about
to reply with the below:
Gabriel,
The OSK string seems constant accross machines, which renders the
patch rather pointless, no? And even if the OSK differs between a
couple of machines, the emulator could easily handle it gracefully.
There are also some technical issues with the patch below, to keep in
mind for future submissions.
> drivers/hwmon/applesmc.c | 18 ++++++++++++++++++
> 1 files changed, 18 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
> index b41baff..0c7cc71 100644
> --- a/drivers/hwmon/applesmc.c
> +++ b/drivers/hwmon/applesmc.c
> @@ -1013,6 +1013,23 @@ static ssize_t applesmc_key_at_index_store(struct device *dev,
> return count;
> }
>
> +static ssize_t applesmc_osk_show(struct device *dev,
> + struct device_attribute *attr, char *sysfsbuf)
> +{
> + int fail;
All other functions use 'ret' here...
> +
> + mutex_lock(&smcreg.mutex);
> + fail = read_smc(APPLESMC_READ_CMD, "OSK0", sysfsbuf, 32) ||
> + read_smc(APPLESMC_READ_CMD, "OSK1", sysfsbuf + 32, 32);
The read function should propagate error messages, i.e., keep the
return values here. And please read to buffers instead.
> + mutex_unlock(&smcreg.mutex);
> + if (fail)
> + return -1;
Return error here.
> +
> + sysfsbuf[64] = '\n';
> + sysfsbuf[65] = '\0';
> + return 65;
A snprintf here, please.
> +}
> +
> static struct led_classdev applesmc_backlight = {
> .name = "smc::kbd_backlight",
> .default_trigger = "nand-disk",
> @@ -1027,6 +1044,7 @@ static struct applesmc_node_group info_group[] = {
> { "key_at_index_type", applesmc_key_at_index_type_show },
> { "key_at_index_data_length", applesmc_key_at_index_data_length_show },
> { "key_at_index_data", applesmc_key_at_index_read_show },
> + { "osk", applesmc_osk_show },
Unfortunately this is not a good place to put random things going
forward.
> { }
> };
>
> --
> 1.7.7.6
>
Given the above issues together with the weak rationale for the patch
in the first place, this patch will not be applied.
Thanks.
Henrik
_______________________________________________
lm-sensors mailing list
lm-sensors@xxxxxxxxxxxxxx
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
