Re: [PATCH v2 0/6] hwmon: (nct6775) Convert to regmap, add i2c support

From: Zev Weiss
Date: Wed Mar 09 2022 - 06:16:26 EST


On Wed, Mar 09, 2022 at 12:12:32AM PST, Paul Menzel wrote:
Dear Zev,


Am 09.03.22 um 01:50 schrieb Zev Weiss:

This is v2 of my patches to add i2c support to the nct6775 driver.

Changes since v1 [0]:
- Added preparatory patch converting driver to regmap API [Guenter]
- Replaced ENOSPC with ENOBUFS and removed WARN_ON() in
nct6775_add_attr_group() [Guenter]
- Added dedicated symbol namespace [Guenter]
- Removed nct6775_write_temp() and nct6775_update_device() symbol
exports [Guenter]
- Reordered patches to put dt-bindings patch first [Krzysztof]

The nct6775-platform and nct6775-i2c drivers have both been tested on
the NCT6779D in an ASRock ROMED8HM3 system and the NCT6798 [1] in an
ASRock X570-D4U (the latter thanks to Renze, CCed); both seem to work
as expected on both systems. I don't have access to any asuswmi
hardware, so testing of the nct6775-platform driver on that to ensure
it doesn't break there would be appreciated (Oleksandr, perhaps?).

I have an ASUS F2A85-M PRO with that Super I/O. (It’s running coreboot right now, but I can test with the proprietary vendor firmware, if you tell me what and how I can test this.


Hi Paul,

Thanks for offering to test! I don't see the F2A85-M PRO listed in the asus_wmi_boards array, so (unless there's some alternate model name it also goes by that's in that list) I don't think it will provide coverage for the asuswmi code, but additional testing of the platform driver would still be good anyway.

To try it out, first apply the patch series on top of Guenter's current hwmon-next tree (it's based on commit 5d4a2ea96b79). You'll need to enable both the existing CONFIG_SENSORS_NCT6775 Kconfig option as well as the new CONFIG_SENSORS_NCT6775_PLATFORM. Then compile, install, and boot into the resulting kernel. If you set CONFIG_SENSORS_NCT6775_PLATFORM=m (compiling it as a module) you'll need to run 'modprobe nct6775-platform' to load the module, after which running 'sensors' from the lm-sensors package should show sensor readings from it -- if things are working right, it should behave pretty much exactly as the driver did prior to these patches.

However, since posting the v2 patch series I realized I bungled something in the regmap conversion (patch 2 of the series), so before compiling you should also apply this small fixup (which will be included in subsequent versions of the patchset):

diff --git a/drivers/hwmon/nct6775-core.c b/drivers/hwmon/nct6775-core.c
index cb3958c977fa..5801aa9d60ee 100644
--- a/drivers/hwmon/nct6775-core.c
+++ b/drivers/hwmon/nct6775-core.c
@@ -1150,7 +1150,7 @@ static int nct6775_write_fan_div(struct nct6775_data *data, int nr)
if (err)
return err;
reg &= 0x70 >> oddshift;
- reg |= data->fan_div[nr] & (0x7 << oddshift);
+ reg |= (data->fan_div[nr] & 0x7) << oddshift;
return nct6775_write_value(data, fandiv_reg, reg);
}


Thanks,
Zev