Hi Team,
I have configured MTIOC7A pin as PWM output for LCD back light PWM. Here below I have attached screen dump of schematic for your reference purpose.
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Used Device Tree
r9a07g043.dtsi => mtu3: timer@10001200 node is already written under soc node in renesas r9a07g043.dtsi and this file is included already.
My custom device tree node is using mtu3 :
&mtu3 {
pinctrl-0 = <&mtu7_pins>;
pinctrl-names = "default";
pwm_mode1 = <7 0>;
pwm_complementary = <7 0>;
#pwm-cells = <2>;
status = "okay";
};
mtu7_pins:mtu7 {
pinmux = <RZG2L_PORT_PINMUX(6, 0, 5)>;
};
dmesg logs:
root@rzg2ul:~# dmesg | grep mtu
[ 2.069393] renesas_mtu3 10001200.timer: ch7: used for pwm mode 1 output at pin MTIOC7A
[ 2.079212] renesas_mtu3 10001200.timer: used for pwm controller of mtu3
[ 2.086122] renesas_mtu3 10001200.timer: ch0: used as clock source
[ 2.101632] renesas_mtu3 10001200.timer: ch1: used for clock events
[ 2.108335] renesas_mtu3 10001200.timer: Renesas MTU3 driver probed
Test Steps:
When I try to enable pwm and setting duty cycle, I have encountered errors while writing.
root@rzg2ul:~# cat /sys/kernel/debug/pwm
platform/10001200.timer, 1 PWM device
pwm-0 (sysfs ): requested period: 0 ns duty: 0 ns polarity: normal
1) root@rzg2ul:~# echo 0 > /sys/class/pwm/pwmchip0/export
2) root@rzg2ul:~# echo 1 > /sys/class/pwm/pwmchip0/pwm0/enable
echo: write error: invalid argument
3)root@rzg2ul:~# echo 500000 > /sys/class/pwm/pwmchip0/pwm0/duty_cycle
echo: write error: invalid argument
Can you please suggest what changes are required to set MTIOC7A as PWM output?
Thanks,
Maulik Manvar
