openwrtv4/package/kernel/mac80211/patches/549-ath9k_enable_gpio_chip.patch

From: Michal Cieslakiewicz <michal.cieslakiewicz@wp.pl>
Date: Sun, 31 Jan 2016 21:01:31 +0100
Subject: [PATCH v4 4/8] mac80211: ath9k: enable access to GPIO

Enable access to GPIO chip and its pins for Atheros AR92xx
wireless devices. For now AR9285 and AR9287 are supported.

Signed-off-by: Michal Cieslakiewicz <michal.cieslakiewicz@wp.pl>
---
 ath9k.h |   23 ++++++++++++
 gpio.c  |  121 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 init.c  |    2 +
 3 files changed, 146 insertions(+)

--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -24,6 +24,7 @@
 #include <linux/completion.h>
 #include <linux/time.h>
 #include <linux/hw_random.h>
+#include <linux/gpio/driver.h>
 
 #include "common.h"
 #include "debug.h"
@@ -817,6 +818,13 @@ void ath_fill_led_pin(struct ath_softc *
 int ath_create_gpio_led(struct ath_softc *sc, int gpio, const char *name,
                         const char *trigger, bool active_low);
 
+/***************/
+/*  GPIO Chip  */
+/***************/
+
+void ath9k_register_gpio_chip(struct ath_softc *sc);
+void ath9k_unregister_gpio_chip(struct ath_softc *sc);
+
 #else
 static inline void ath_init_leds(struct ath_softc *sc)
 {
@@ -828,6 +836,14 @@ static inline void ath_deinit_leds(struc
 static inline void ath_fill_led_pin(struct ath_softc *sc)
 {
 }
+
+static inline void ath9k_register_gpio_chip(struct ath_softc *sc)
+{
+}
+
+static inline void ath9k_unregister_gpio_chip(struct ath_softc *sc)
+{
+}
 #endif
 
 /************************/
@@ -963,6 +979,12 @@ struct ath_led {
 	struct led_classdev cdev;
 };
 
+struct ath9k_gpio_chip {
+	struct ath_softc *sc;
+	char label[32];
+	struct gpio_chip gchip;
+};
+
 struct ath_softc {
 	struct ieee80211_hw *hw;
 	struct device *dev;
@@ -1017,6 +1039,7 @@ struct ath_softc {
 #ifdef CPTCFG_MAC80211_LEDS
 	const char *led_default_trigger;
 	struct list_head leds;
+	struct ath9k_gpio_chip *gpiochip;
 #endif
 
 #ifdef CPTCFG_ATH9K_DEBUGFS
--- a/drivers/net/wireless/ath/ath9k/gpio.c
+++ b/drivers/net/wireless/ath/ath9k/gpio.c
@@ -22,6 +22,9 @@
 /********************************/
 
 #ifdef CPTCFG_MAC80211_LEDS
+
+#include <asm-generic/gpio.h>
+
 static void ath_led_brightness(struct led_classdev *led_cdev,
 			       enum led_brightness brightness)
 {
@@ -60,6 +63,10 @@ static int ath_add_led(struct ath_softc
 	else
 		ath9k_hw_set_gpio(sc->sc_ah, gpio->gpio, gpio->active_low);
 
+	/* If there is GPIO chip configured, reserve LED pin */
+	if (sc->gpiochip)
+		gpio_request(sc->gpiochip->gchip.base + gpio->gpio, gpio->name);
+
 	return 0;
 }
 
@@ -116,6 +123,9 @@ void ath_deinit_leds(struct ath_softc *s
 
 	while (!list_empty(&sc->leds)) {
 		led = list_first_entry(&sc->leds, struct ath_led, list);
+		/* If there is GPIO chip configured, free LED pin */
+		if (sc->gpiochip)
+			gpio_free(sc->gpiochip->gchip.base + led->gpio->gpio);
 		list_del(&led->list);
 		ath_led_brightness(&led->cdev, LED_OFF);
 		led_classdev_unregister(&led->cdev);
@@ -186,6 +196,117 @@ void ath_fill_led_pin(struct ath_softc *
 	/* LED off, active low */
 	ath9k_hw_set_gpio(ah, ah->led_pin, (ah->config.led_active_high) ? 0 : 1);
 }
+
+/***************/
+/*  GPIO Chip  */
+/***************/
+
+/* gpio_chip handler : set GPIO to input */
+static int ath9k_gpio_pin_cfg_input(struct gpio_chip *chip, unsigned offset)
+{
+	struct ath9k_gpio_chip *gc = container_of(chip, struct ath9k_gpio_chip,
+						  gchip);
+
+	ath9k_hw_cfg_gpio_input(gc->sc->sc_ah, offset);
+
+	return 0;
+}
+
+/* gpio_chip handler : set GPIO to output */
+static int ath9k_gpio_pin_cfg_output(struct gpio_chip *chip, unsigned offset,
+				     int value)
+{
+	struct ath9k_gpio_chip *gc = container_of(chip, struct ath9k_gpio_chip,
+						  gchip);
+
+	ath9k_hw_cfg_output(gc->sc->sc_ah, offset,
+			    AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
+	ath9k_hw_set_gpio(gc->sc->sc_ah, offset, value);
+
+	return 0;
+}
+
+/* gpio_chip handler : query GPIO direction (0=out, 1=in) */
+static int ath9k_gpio_pin_get_dir(struct gpio_chip *chip, unsigned offset)
+{
+	struct ath9k_gpio_chip *gc = container_of(chip, struct ath9k_gpio_chip,
+						  gchip);
+	struct ath_hw *ah = gc->sc->sc_ah;
+
+	return !((REG_READ(ah, AR_GPIO_OE_OUT) >> (offset * 2)) & 3);
+}
+
+/* gpio_chip handler : get GPIO pin value */
+static int ath9k_gpio_pin_get(struct gpio_chip *chip, unsigned offset)
+{
+	struct ath9k_gpio_chip *gc = container_of(chip, struct ath9k_gpio_chip,
+						  gchip);
+
+	return ath9k_hw_gpio_get(gc->sc->sc_ah, offset);
+}
+
+/* gpio_chip handler : set GPIO pin to value */
+static void ath9k_gpio_pin_set(struct gpio_chip *chip, unsigned offset,
+			       int value)
+{
+	struct ath9k_gpio_chip *gc = container_of(chip, struct ath9k_gpio_chip,
+						  gchip);
+
+	ath9k_hw_set_gpio(gc->sc->sc_ah, offset, value);
+}
+
+/* register GPIO chip */
+void ath9k_register_gpio_chip(struct ath_softc *sc)
+{
+	struct ath9k_gpio_chip *gc;
+	u16 ng;
+
+	/* for now only AR9285 and AR9287 are recognized */
+	if (AR_SREV_9287(sc->sc_ah))
+		ng = AR9287_NUM_GPIO;
+	else if (AR_SREV_9285(sc->sc_ah))
+		ng = AR9285_NUM_GPIO;
+	else
+		return;
+
+	gc = kzalloc(sizeof(struct ath9k_gpio_chip), GFP_KERNEL);
+	if (!gc)
+		return;
+
+	snprintf(gc->label, sizeof(gc->label), "ath9k-%s",
+		 wiphy_name(sc->hw->wiphy));
+	gc->gchip.label = gc->label;
+	gc->gchip.base = -1;	/* determine base automatically */
+	gc->gchip.ngpio = ng;
+	gc->gchip.direction_input = ath9k_gpio_pin_cfg_input;
+	gc->gchip.direction_output = ath9k_gpio_pin_cfg_output;
+	gc->gchip.get_direction = ath9k_gpio_pin_get_dir;
+	gc->gchip.get = ath9k_gpio_pin_get;
+	gc->gchip.set = ath9k_gpio_pin_set;
+	gc->gchip.owner = THIS_MODULE;
+
+	if (gpiochip_add(&gc->gchip)) {
+		kfree(gc);
+		return;
+	}
+
+	sc->gpiochip = gc;
+	gc->sc = sc;
+}
+
+/* remove GPIO chip */
+void ath9k_unregister_gpio_chip(struct ath_softc *sc)
+{
+	struct ath9k_gpio_chip *gc = sc->gpiochip;
+
+	if (!gc)
+		return;
+
+	gpiochip_remove(&gc->gchip);
+	kfree(gc);
+	sc->gpiochip = NULL;
+}
+
 #endif
 
 /*******************/
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -975,6 +975,7 @@ int ath9k_init_device(u16 devid, struct
 			goto debug_cleanup;
 	}
 
+	ath9k_register_gpio_chip(sc);
 	ath_init_leds(sc);
 	ath_start_rfkill_poll(sc);
 
@@ -1022,6 +1023,7 @@ void ath9k_deinit_device(struct ath_soft
 
 	wiphy_rfkill_stop_polling(sc->hw->wiphy);
 	ath_deinit_leds(sc);
+	ath9k_unregister_gpio_chip(sc);
 
 	ath9k_ps_restore(sc);