forked from mirror/openwrt
c2e5bded8d
The SPI chip select GPIO polarity is active low by default. We must
use "spi-cs-high" dts property to toggle the polarity. The polarity
on "cs-gpios" won't take effect at all[1]. Fix these incorrect GPIO
polarities to silence the kernel warnings.
[1] Refer to Linux/Documentation/devicetree/bindings/spi/spi-controller.yaml
```
device node | cs-gpio | CS pin state active | Note
================+===============+=====================+=====
spi-cs-high | - | H |
- | - | L |
spi-cs-high | ACTIVE_HIGH | H |
- | ACTIVE_HIGH | L | 1
spi-cs-high | ACTIVE_LOW | H | 2
- | ACTIVE_LOW | L |
Notes:
1) Should print a warning about polarity inversion.
Here it would be wise to avoid and define the gpio as
ACTIVE_LOW.
2) Should print a warning about polarity inversion
because ACTIVE_LOW is overridden by spi-cs-high.
Should be generally avoided and be replaced by
spi-cs-high + ACTIVE_HIGH.
```
Signed-off-by: Shiji Yang <yangshiji66@outlook.com>
Link: https://github.com/openwrt/openwrt/pull/19845
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
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| .. | ||
| base-files/etc | ||
| dts | ||
| files/drivers | ||
| image | ||
| mt76x8 | ||
| mt7620 | ||
| mt7621 | ||
| patches-6.12 | ||
| rt288x | ||
| rt305x | ||
| rt3883 | ||
| Makefile | ||
| modules.mk | ||