On 02/25/2015 04:36 AM, Simon Guinot wrote:
On Mon, Feb 23, 2015 at 06:49:50AM -0800, Guenter Roeck wrote:
On 02/23/2015 06:40 AM, Simon Guinot wrote:
On Mon, Feb 23, 2015 at 06:10:59AM -0800, Guenter Roeck wrote:
On 02/23/2015 05:02 AM, Simon Guinot wrote:
On the LaCie 2Big Network v2 (net2big_v2) board, the fan alarm is not
wired to the I2C fan controller but to a separe GPIO. This GPIO can be
controlled by using the gpio-fan driver.
This patch adds the gpio-fan alarm description in the net2big_v2 DTS.
Signed-off-by: Simon Guinot <simon.guinot@xxxxxxxxxxxx>
---
arch/arm/boot/dts/kirkwood-net2big.dts | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/arm/boot/dts/kirkwood-net2big.dts b/arch/arm/boot/dts/kirkwood-net2big.dts
index 53dc37a3b687..e4f7e497379f 100644
--- a/arch/arm/boot/dts/kirkwood-net2big.dts
+++ b/arch/arm/boot/dts/kirkwood-net2big.dts
@@ -27,6 +27,11 @@
device_type = "memory";
reg = <0x00000000 0x10000000>;
};
+
+ gpio_fan {
+ compatible = "gpio-fan";
+ alarm-gpios = <&gpio0 25 GPIO_ACTIVE_LOW>;
+ };
};
®ulators {
Again, wrong solution, and conceptually wrong as well from a dt perspective.
The alarm signal should be handled by the g762 driver, and the alarm-gpios
property should be added to the g762 description.
OK. Then you think it would be better to add support for alarm GPIOs
support in the g762. The problem is that we should have to find a
generic way to do that. After all, we could want the very same
modification for a bunch of fan drivers.
Can't help it. After all, the interrupt handling logic is different for each chip,
and there are non-DT systems out there.
The g762 property should probably be something like
g762@3e {
compatible = "gmt,g762";
reg = <0x3e>;
clocks = <&g762_clk>;
interrupt-parent = <&gpio0>;
interrupts = <25 GPIO_ACTIVE_LOW>;
};
struct i2c_client has an irq field, and as far as I can see it is filled in
automatically from the dt node. So all the driver should have to do is to
implement an interrupt handler.
Is that OK to pass a GPIO line through the "interrupts" property ?
Why not ? That is how it is supposed to be used. The driver neither needs
to know nor should know that its interrupt line is connected to a gpio pin.
Moreover it seems to me that g763 controller (compatible) supports
alert interrupts through SMBus. Then maybe we should save the
"interrupts" property for this signal ?
You lost me there. The SMBus alert signal is shared among multiple chips.
If a system supports it, it should be connected to the alert interrupt handler
(in i2c-smbus.c), which would handle it and pass it to a driver's alert function.
Don't you think it would be more explicit to have a separate DT
property (such as "gpio-alarm") and also a dedicated field in the
g762 platform data structure ?
No. It would add an unnecessary dependency on gpio (or, rather, gpio
driven interrupts) to the g762 driver, and it would limit its usability.
Guenter
_______________________________________________
lm-sensors mailing list
lm-sensors@xxxxxxxxxxxxxx
http://lists.lm-sensors.org/mailman/listinfo/lm-sensors
