[PATCH] brcmfmac: Obtain reset GPIO

[Linus Walleij <linus.walleij@linaro.org>]

This grabs the reset GPIO and holds it de-asserted, if available.
Asserting this signal will make the SDIO card re-enumerate.

Cc: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
 .../net/wireless/broadcom/brcm80211/brcmfmac/common.c  | 10 ++++++++++
 .../net/wireless/broadcom/brcm80211/brcmfmac/common.h  |  4 ++++
 2 files changed, 14 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
index e3758bd86acf..40e18ebfe1ea 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.c
@@ -446,6 +446,16 @@ struct brcmf_mp_device *brcmf_get_module_param(struct device *dev,
 		brcmf_dmi_probe(settings, chip, chiprev);
 		brcmf_of_probe(dev, bus_type, settings);
 	}
+	/* Fetch WL_RESET GPIO and de-assert it, if available */
+	settings->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+	if (settings->reset) {
+		/*
+		 * If we found a reset GPIO, we may have just de-asserted it
+		 * so wait some 8 ms for PLLs to lock, se figure 32, WLAN
+		 * boot-up sequence in the manual.
+		 */
+		usleep_range(8000, 10000);
+	}
 	return settings;
 }
 
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
index 8b5f49997c8b..4209e71ebcdd 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/common.h
@@ -7,6 +7,7 @@
 
 #include <linux/platform_device.h>
 #include <linux/platform_data/brcmfmac.h>
+#include <linux/gpio/consumer.h>
 #include "fwil_types.h"
 
 #define BRCMF_FW_ALTPATH_LEN			256
@@ -39,6 +40,8 @@ extern struct brcmf_mp_global_t brcmf_mp_global;
  * @roamoff: Firmware roaming off?
  * @ignore_probe_fail: Ignore probe failure.
  * @country_codes: If available, pointer to struct for translating country codes
+ * @board_type: String with the board type name
+ * @reset: GPIO descriptor for the RESET line
  * @bus: Bus specific platform data. Only SDIO at the mmoment.
  */
 struct brcmf_mp_device {
@@ -50,6 +53,7 @@ struct brcmf_mp_device {
 	bool		ignore_probe_fail;
 	struct brcmfmac_pd_cc *country_codes;
 	const char	*board_type;
+	struct gpio_desc *reset;
 	union {
 		struct brcmfmac_sdio_pd sdio;
 	} bus;
-- 
2.30.2