From: Alexis Lothoré alexis.lothore@bootlin.com
[ Upstream commit f3ec643947634bed41b97bd56b248f7c78498eab ]
This reverts commit fcf690b0b47494df51d214db5c5a714a400b0257.
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 f31ee3c0a555 ("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 ec031ac4792c ("wilc1000: Add reset/enable GPIO support to SPI driver") was applying the correct logic. But commit fcf690b0b474 ("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: fcf690b0b474 ("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.c... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/microchip/wilc1000/spi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/microchip/wilc1000/spi.c b/drivers/net/wireless/microchip/wilc1000/spi.c index 77b4cdff73c37..4cf8586ed55ae 100644 --- a/drivers/net/wireless/microchip/wilc1000/spi.c +++ b/drivers/net/wireless/microchip/wilc1000/spi.c @@ -192,11 +192,11 @@ 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); }