korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-15 15:04:27 +08:00
Code Issues Packages Projects Releases Wiki Activity

wifi: wilc1000: revert reset line logic flip

Browse Source 
This reverts commit fcf690b0b4.

When using a wilc1000 chip over a spi bus, users can optionally define a
reset gpio and a chip enable gpio. The reset line of wilc1000 is active
low, so to hold the chip in reset, a low (physical) value must be applied.

The corresponding device tree binding documentation was introduced by
commit f31ee3c0a5 ("wilc1000: Document enable-gpios and reset-gpios
properties") and correctly indicates that the reset line is an active-low
signal. The corresponding driver part, brought by commit ec031ac479
("wilc1000: Add reset/enable GPIO support to SPI driver") was applying the
correct logic. But commit fcf690b0b4 ("wifi: wilc1000: use correct
sequence of RESET for chip Power-UP/Down") eventually flipped this logic
and started misusing the gpiod APIs, applying an inverted logic when
powering up/down the chip (for example, setting the reset line to a logic
"1" during power up, which in fact asserts the reset line when device tree
describes the reset line as GPIO_ACTIVE_LOW). As a consequence, any
platform currently using the driver in SPI mode must use a faulty reset
line description in device tree, or else chip will be maintained in reset
and will not even allow to bring up the chip.

Fix reset line usage by inverting back the gpiod APIs usage, setting the
reset line to the logic value "0" when powering the chip, and the logic
value "1" when powering off the chip.

Fixes: fcf690b0b4 ("wifi: wilc1000: use correct sequence of RESET for chip Power-UP/Down")
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Ajay Singh <ajay.kathat@microchip.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240217-wilc_1000_reset_line-v2-1-b216f433d7d5@bootlin.com
This commit is contained in:
Alexis Lothoré 2024-02-17 14:22:41 +01:00 committed by Kalle Valo
parent 32167707aa
commit f3ec643947
1 changed files with 3 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/net/wireless/microchip/wilc1000/spi.c
View File

@ -194,11 +194,11 @@ static void wilc_wlan_power(struct wilc *wilc, bool on)
/* assert ENABLE: */
gpiod_set_value(gpios->enable, 1);
mdelay(5);
/* assert RESET: */
gpiod_set_value(gpios->reset, 1);
} else {
/* deassert RESET: */
gpiod_set_value(gpios->reset, 0);
} else {
/* assert RESET: */
gpiod_set_value(gpios->reset, 1);
/* deassert ENABLE: */
gpiod_set_value(gpios->enable, 0);
}