wilc1000: Add reset/enable GPIO support to SPI driver
For the SDIO driver, the RESET/ENABLE pins of WILC1000 are controlled
through the SDIO power sequence driver. This commit adds analogous
support for the SPI driver. Specifically, during initialization, the
chip will be ENABLEd and taken out of RESET and during
deinitialization, the chip will be placed back into RESET and disabled
(both to reduce power consumption and to ensure the WiFi radio is
off).
Both RESET and ENABLE GPIOs are optional. However, if the ENABLE GPIO
is specified, then the RESET GPIO should normally also be specified as
otherwise there is no way to ensure proper timing of the ENABLE/RESET
sequence.
Signed-off-by: David Mosberger-Tang <davidm@egauge.net>
Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20211221212531.4011609-2-davidm@egauge.net
diff --git a/drivers/net/wireless/microchip/wilc1000/spi.c b/drivers/net/wireless/microchip/wilc1000/spi.c
index 5ace9e3..2c2ed4b 100644
--- a/drivers/net/wireless/microchip/wilc1000/spi.c
+++ b/drivers/net/wireless/microchip/wilc1000/spi.c
@@ -8,6 +8,7 @@
#include <linux/spi/spi.h>
#include <linux/crc7.h>
#include <linux/crc-itu-t.h>
+#include <linux/gpio/consumer.h>
#include "netdev.h"
#include "cfg80211.h"
@@ -45,6 +46,10 @@
bool probing_crc; /* true if we're probing chip's CRC config */
bool crc7_enabled; /* true if crc7 is currently enabled */
bool crc16_enabled; /* true if crc16 is currently enabled */
+ struct wilc_gpios {
+ struct gpio_desc *enable; /* ENABLE GPIO or NULL */
+ struct gpio_desc *reset; /* RESET GPIO or NULL */
+ } gpios;
};
static const struct wilc_hif_func wilc_hif_spi;
@@ -152,6 +157,50 @@
u8 status;
} __packed;
+static int wilc_parse_gpios(struct wilc *wilc)
+{
+ struct spi_device *spi = to_spi_device(wilc->dev);
+ struct wilc_spi *spi_priv = wilc->bus_data;
+ struct wilc_gpios *gpios = &spi_priv->gpios;
+
+ /* get ENABLE pin and deassert it (if it is defined): */
+ gpios->enable = devm_gpiod_get_optional(&spi->dev,
+ "enable", GPIOD_OUT_LOW);
+ /* get RESET pin and assert it (if it is defined): */
+ if (gpios->enable) {
+ /* if enable pin exists, reset must exist as well */
+ gpios->reset = devm_gpiod_get(&spi->dev,
+ "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(gpios->reset)) {
+ dev_err(&spi->dev, "missing reset gpio.\n");
+ return PTR_ERR(gpios->reset);
+ }
+ } else {
+ gpios->reset = devm_gpiod_get_optional(&spi->dev,
+ "reset", GPIOD_OUT_HIGH);
+ }
+ return 0;
+}
+
+static void wilc_wlan_power(struct wilc *wilc, bool on)
+{
+ struct wilc_spi *spi_priv = wilc->bus_data;
+ struct wilc_gpios *gpios = &spi_priv->gpios;
+
+ if (on) {
+ /* assert ENABLE: */
+ gpiod_set_value(gpios->enable, 1);
+ mdelay(5);
+ /* 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);
+ }
+}
+
static int wilc_bus_probe(struct spi_device *spi)
{
int ret;
@@ -171,6 +220,10 @@
wilc->bus_data = spi_priv;
wilc->dev_irq_num = spi->irq;
+ ret = wilc_parse_gpios(wilc);
+ if (ret < 0)
+ goto netdev_cleanup;
+
wilc->rtc_clk = devm_clk_get_optional(&spi->dev, "rtc");
if (IS_ERR(wilc->rtc_clk)) {
ret = PTR_ERR(wilc->rtc_clk);
@@ -983,9 +1036,10 @@
static int wilc_spi_deinit(struct wilc *wilc)
{
- /*
- * TODO:
- */
+ struct wilc_spi *spi_priv = wilc->bus_data;
+
+ spi_priv->isinit = false;
+ wilc_wlan_power(wilc, false);
return 0;
}
@@ -1006,6 +1060,8 @@
dev_err(&spi->dev, "Fail cmd read chip id...\n");
}
+ wilc_wlan_power(wilc, true);
+
/*
* configure protocol
*/
diff --git a/drivers/net/wireless/microchip/wilc1000/wlan.c b/drivers/net/wireless/microchip/wilc1000/wlan.c
index a2aa889..fb5633a 100644
--- a/drivers/net/wireless/microchip/wilc1000/wlan.c
+++ b/drivers/net/wireless/microchip/wilc1000/wlan.c
@@ -1254,7 +1254,7 @@
wilc->rx_buffer = NULL;
kfree(wilc->tx_buffer);
wilc->tx_buffer = NULL;
- wilc->hif_func->hif_deinit(NULL);
+ wilc->hif_func->hif_deinit(wilc);
}
static int wilc_wlan_cfg_commit(struct wilc_vif *vif, int type,
