Re: [PATCH 3/4] ARM: dts: sun8i-a83t-tbs-a711: Add support for the vibrator motor

Hello,

On Mon, Feb 24, 2020 at 10:10:59AM +0100, Maxime Ripard wrote:

Hi,

On Sun, Feb 23, 2020 at 12:14:27AM +0100, Ondrej Jirman wrote:

quoted

The board has a vibrator mottor. Hook it to the input subsystem.

Signed-off-by: Ondrej Jirman <redacted>
---
 arch/arm/boot/dts/sun8i-a83t-tbs-a711.dts | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/arm/boot/dts/sun8i-a83t-tbs-a711.dts b/arch/arm/boot/dts/sun8i-a83t-tbs-a711.dts
index 2fd31a0a0b344..a22920275e99b 100644
--- a/arch/arm/boot/dts/sun8i-a83t-tbs-a711.dts
+++ b/arch/arm/boot/dts/sun8i-a83t-tbs-a711.dts

@@ -99,6 +99,11 @@ panel_input: endpoint {
 		};
 	};

+	vibrator {
+		compatible = "gpio-vibrator";
+		vcc-supply = <&reg_ldo_io1>;
+	};
+

LDO IO1 can also be muxed in as a GPIO iirc, why did you choose the
regulator instead?

According to the specification, LDO needs to be enabled (value 0b11)
to achieve the specified max driving current of 150mA:

  https://megous.com/dl/tmp/92b7d9d94820c3ba.png

Otherwise the chip is probably just using the regular CMOS logic output
(typically limited to around 20-35mA, but not specified in this datasheet),
which would be probably overdriven, if we try to drive the motor with it.

And since we're driving a motor directly, the more the better.

thank you and regards,
	o.

Maxime