Devicetree i.MX8MP with PCA9544A

[Ralf_Rademacher]

Can anyone tell me what a devicetree entry must look like if I want to implement the following constellation? 

i hope you understand what i'm trying to describe.

I only found examples without handling the interupt of an child node of pca954x.

thx in advance

[Ralf_Rademacher · Accepted solution]

The thread can be closed as there was no other good solution than to implement it in the form of a userspace driver.

[Ralf_Rademacher]

Is there really nobody who ever has used pca954x in a Linux system, with an child node, which generates an interrupt? who can provide an complete and full working devicetree entry, which contains everything i need to get this circuit work propperly?

[Ralf_Rademacher]

Hello, i added much debugoutput to several kernelfunctions and to the drivers...

The problem seems to be, that somehow there is a problem getting the right irqdomain.

I2C Bus

[    5.130661] [DBGMSG] request_threaded_irq :action->handler: 0x10DBA3F8
[    5.130664] [DBGMSG] request_threaded_irq :action->thread_fn: 0x0
[    5.137199] [DBGMSG] request_threaded_irq :action->flags: 0x4080
[    5.143311] [DBGMSG] request_threaded_irq :action->name: 30a50000.i2c
[    5.149328] [DBGMSG] request_threaded_irq :action->dev_id: 0x67AB2080
[    5.155803] [DBGMSG] request_threaded_irq :leaving fxn the normal way

PCA9544A

[    5.169785] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.169788] [DBGMSG] irq_find_mapping :hwirq: 0x6
[    5.177110] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x63
[    5.181825] [DBGMSG] irq_find_mapping  using domain @00000000d8881a92
[    5.195331] [DBGMSG] pca954x_probe :entering pca954x_probe
[    5.201139] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.201141] [DBGMSG] irq_find_mapping :hwirq: 0x0
[    5.208461] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x0
[    5.213171] [DBGMSG] irq_find_mapping  using domain @0000000059dfe323
[    5.226625] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.226629] [DBGMSG] irq_find_mapping :hwirq: 0x1
[    5.233945] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x0
[    5.238657] [DBGMSG] irq_find_mapping  using domain @0000000059dfe323
[    5.253205] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.253214] [DBGMSG] irq_find_mapping :hwirq: 0x2
[    5.260621] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x0
[    5.265360] [DBGMSG] irq_find_mapping  using domain @0000000059dfe323
[    5.278843] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.278845] [DBGMSG] irq_find_mapping :hwirq: 0x3
[    5.286176] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x0
[    5.290904] [DBGMSG] irq_find_mapping  using domain @0000000059dfe323

APDS9960 (Sensor 1)

[    5.308440] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    5.308442] [DBGMSG] irq_find_mapping :hwirq: 0x0
[    5.315776] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x5D
[    5.320510] [DBGMSG] irq_find_mapping  using domain @00000000d8881a92
[    5.334083] [DBGMSG] apds9960_probe :enter apds probe
[    6.096343] [DBGMSG] request_threaded_irq :action->handler: 0x10167F50
[    6.101438] [DBGMSG] request_threaded_irq :action->thread_fn: 0x10F5F404
[    6.107990] [DBGMSG] request_threaded_irq :action->flags: 0x2082
[    6.114708] [DBGMSG] request_threaded_irq :action->name: apds9960_event
[    6.120736] [DBGMSG] request_threaded_irq :action->dev_id: 0x67AB3800
[    6.127397] [DBGMSG] setup_irq_thread :enter fxn
[    6.136793] [DBGMSG] request_threaded_irq :leaving fxn the normal way
[    6.137148] [DBGMSG] irq_thread :enter fxn
[    6.141451] [DBGMSG] apds9960_probe :client->irq: 0x5D / interrupt_handler_fxn: 0x10F5F404

APDS9960 (Sensor 2)

[    6.169614] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    6.169616] [DBGMSG] irq_find_mapping :hwirq: 0x1
[    6.176983] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x5E
[    6.181721] [DBGMSG] irq_find_mapping  using domain @00000000d8881a92
[    6.195365] [DBGMSG] apds9960_probe :enter apds probe
[    6.524923] [DBGMSG] request_threaded_irq :action->handler: 0x10167F50
[    6.530004] [DBGMSG] request_threaded_irq :action->thread_fn: 0x10F5F404
[    6.536558] [DBGMSG] request_threaded_irq :action->flags: 0x2082
[    6.543280] [DBGMSG] request_threaded_irq :action->name: apds9960_event
[    6.549309] [DBGMSG] request_threaded_irq :action->dev_id: 0x67AB4800
[    6.555964] [DBGMSG] setup_irq_thread :enter fxn
[    6.565125] [DBGMSG] request_threaded_irq :leaving fxn the normal way
[    6.565502] [DBGMSG] irq_thread :enter fxn
[    6.569770] [DBGMSG] apds9960_probe :client->irq: 0x5E / interrupt_handler_fxn: 0x10F5F404

APDS9960 (Sensor 3)

[    6.597743] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[    6.597745] [DBGMSG] irq_find_mapping :hwirq: 0x2
[    6.605093] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x5F
[    6.609827] [DBGMSG] irq_find_mapping  using domain @00000000d8881a92
[    6.623459] [DBGMSG] apds9960_probe :enter apds probe
[    7.580221] [DBGMSG] request_threaded_irq :action->handler: 0x10167F50
[    7.585311] [DBGMSG] request_threaded_irq :action->thread_fn: 0x10F5F404
[    7.591861] [DBGMSG] request_threaded_irq :action->flags: 0x2082
[    7.598579] [DBGMSG] request_threaded_irq :action->name: apds9960_event
[    7.604609] [DBGMSG] request_threaded_irq :action->dev_id: 0x67AB5800
[    7.611261] [DBGMSG] setup_irq_thread :enter fxn
[    7.620473] [DBGMSG] request_threaded_irq :leaving fxn the normal way
[    7.620833] [DBGMSG] irq_thread :enter fxn
[    7.625131] [DBGMSG] apds9960_probe :client->irq: 0x5F / interrupt_handler_fxn: 0x10F5F404



IRQ was generated at the second sensor

[   68.221782] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[   68.221788] [DBGMSG] irq_find_mapping :hwirq: 0x6					// CORRECT PIN WAS DETERMINED AT IMX8MP
[   68.229103] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0x63		// CORRECT IRQ DETERMINED (pca954x)
[   68.233809] [DBGMSG] irq_find_mapping  using domain @00000000d8881a92		// SAME POINTER AS pca954x, APDS9960 (sensor 1-3)
[   68.247618] [DBGMSG] irq_thread_fn :enter fxn
[   68.247622] [DBGMSG] irq_thread_fn :action->handler: 0x10167F50
[   68.252005] [DBGMSG] irq_thread_fn :action->thread_fn: 0x10DC0950
[   68.257949] [DBGMSG] irq_thread_fn :action->flags: 0x2082
[   68.264057] [DBGMSG] irq_thread_fn :action->name: pca954x
[   68.269462] [DBGMSG] irq_thread_fn :action->dev_id: 0x67A9D8F8
[   68.274867] [DBGMSG] pca954x_irq_handler :entering pca954x_irq_handler		// ENTERING CORRECT HANDLER (pca954x)
[   68.281554] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq] is returned
[   68.288099] [DBGMSG] irq_find_mapping :hwirq: 0x1					// CORRECT PIN AT pca954x IS DETERMINED, WHERE SECOND SENSORS INT SIGNAL IS ATTACHED TO
[   68.295415] [DBGMSG] irq_find_mapping :domain->linear_revmap[hwirq]: 0xDF		// I DONT UNDERSTAND, WHERE THIS IRQ COME FROM. 0xDE, 0xDF and 0xE0 is not listed under /proc/irq or /proc/interrupts
[   68.300127] [DBGMSG] irq_find_mapping  using domain @0000000059dfe323
[   68.313621] [DBGMSG] handle_nested_irq :entering handle_nested_irq
[   68.313623] [DBGMSG] handle_nested_irq :irq: 0xDF					// NOW HANDLE_NESTED_IRQ HAS DETERMINED A IRQ WHICH IS UNKNOWN TO ME
[   68.319811] [DBGMSG] handle_nested_irq :irq_desc->name: null				// THATS WHY ALL FOLLOWING VARIABLES ARE WRONG AND INVALID
[   68.324527] [DBGMSG] handle_nested_irq :irq_desc->parent_irq: 0x00			// SAME HERE
[   68.330202] [DBGMSG] handle_nested_irq :action: false or null			// SAME HERE
[   68.336380] [DBGMSG] handle_nested_irq :irqd_irq_disabled: true			// CHECK FAILS AS RESULT
[   68.342122] [DBGMSG] handle_nested_irq :result of (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) : true	// FALSE CONDITION IS USED
[   68.348037] [DBGMSG] handle_nested_irq :goto out_unlock				// IRQ IS NOT HANDLED, BECAUSE apds9960_interrupt_handler // WAS NOT TRIGGERED

[AldoG]

Hello,

You may take the i.MX8MM with the 8MIC board device tree as reference, which make use of the PCA9555 as you want to use the PCA954x
https://github.com/nxp-imx/linux-imx/blob/lf-5.15.y/arch/arm64/boot/dts/freescale/imx8mm-evk-8mic-re...

Also, you may refer to the device tree binding documentation:
https://github.com/nxp-imx/linux-imx/blob/fa6c3168595c02bd9d5366fcc28c9e7304947a3d/Documentation/dev...

Best regards,
Aldo.

[Ralf_Rademacher]

Thx @AldoG ,

but the links were not very useful.

i found a configuration which partially works. but it did not refer back on the child node. so i think in the proximity@39 node i still need a pinctrl. (the driver tells me this during probe) but i have no idea how a pinctrl has to look for pca9544a. i only find examples for imx8..

	i2c4_mux_apds: i2c4-mux-pca9544@70 {
		compatible = "nxp,pca9544";
		#address-cells = <1>;
		#size-cells = <0>;
		reg = <0x70>;
		interrupt-parent = <&gpio2>;
		interrupt-controller;
		pinctrl-names = "default";
		pinctrl-0 = <&pinctrl_pca9544a_70>;
		interrupts = <6 IRQ_TYPE_EDGE_FALLING>;
		interrupt-cells = <2>;

		i2c@0 {
			#address-cells = <1>;
			#size-cells = <0>;
			reg = <0>;

			proximity@39 {
				compatible = "avago,apds9960";
				reg = <0x39>;
				interrupts = <0 IRQ_TYPE_EDGE_FALLING>;
				interrupt-parent = <&i2c4_mux_apds>;
				};
		};

		i2c@1 {
			#address-cells = <1>;
			#size-cells = <0>;
			reg = <1>;

			proximity@39 {
				compatible = "avago,apds9960";
				reg = <0x39>;
				interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
				interrupt-parent = <&i2c4_mux_apds>;
				};
		};

has anyone an idea how to do?

Best Ralf