On Mon, Aug 19, 2019 at 2:17 PM Max Staudt <max@xxxxxxxxx> wrote:
Since the 2019 a1k.org community re-print of these PCBs sports an
LTC2990 hwmon chip as an example use case, let this driver autoprobe
for that as well. If it is present, modprobing ltc2990 is sufficient.
The property_entry enables the three additional inputs available on
this particular board:
in1 will be the voltage of the 5V rail, divided by 2.
in2 will be the voltage of the 12V rail, divided by 4.
temp3 will be measured using a PCB loop next the chip.
v5: Style
v4: Style
Added other possible addresses for LTC2990.
v3: Merged with initial LTC2990 support on ICY.
Moved defaults from platform_data to swnode.
Added note to Kconfig.
Signed-off-by: Max Staudt <max@xxxxxxxxx>
Reviewed-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
One comment below...
--- a/drivers/i2c/busses/i2c-icy.c
+++ b/drivers/i2c/busses/i2c-icy.c
@@ -141,6 +166,35 @@ static int icy_probe(struct zorro_dev *z,
dev_info(&z->dev, "ICY I2C controller at %pa, IRQ not implemented\n",
&z->resource.start);
+ /*
+ * The 2019 a1k.org PCBs have an LTC2990 at 0x4c, so start
+ * it automatically once ltc2990 is modprobed.
+ *
+ * in0 is the voltage of the internal 5V power supply.
+ * temp1 is the temperature inside the chip.
+ *
+ * See property_entry above for in1, in2, temp3.
+ */
+ new_fwnode = fwnode_create_software_node(icy_ltc2990_props, NULL);
+ if (IS_ERR(new_fwnode)) {
+ dev_info(&z->dev, "Failed to create fwnode for LTC2990, error: %ld\n",
+ PTR_ERR(new_fwnode));
+ } else {
+ /*
+ * Store the fwnode so we can destroy it on .remove().
+ * Only store it on success, as fwnode_remove_software_node()
+ * is NULL safe, but not PTR_ERR safe.
+ */
+ i2c->ltc2990_fwnode = new_fwnode;
+ ltc2990_info.fwnode = new_fwnode;
+
+ i2c->ltc2990_client =
+ i2c_new_probed_device(&i2c->adapter,
+ <c2990_info,
+ icy_ltc2990_addresses,
+ NULL);
+ }
+
return 0;
}
Since commit d3e1b617ae20c459 ("i2c: allow specify device properties in
i2c_board_info"), the properties could be provided by info->properties, too.
However, according to the comments for device_add_properties(), this is
valid only if there is a real firmware node present.
If that is true, Max' use is correct, while e.g. commit 6a7836ba7fb4abf6
("ARM: imx: pca100: use device properties for at24 eeprom") isn't?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
