OpenWrt – Rev 1

Subversion Repositories:
Rev:
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>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
--- 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"
@@ -1001,6 +1002,14 @@ struct ath_led {
        struct led_classdev cdev;
 };
 
+#ifdef CONFIG_GPIOLIB
+struct ath9k_gpio_chip {
+       struct ath_softc *sc;
+       char label[32];
+       struct gpio_chip gchip;
+};
+#endif
+
 struct ath_softc {
        struct ieee80211_hw *hw;
        struct device *dev;
@@ -1058,6 +1067,9 @@ struct ath_softc {
 #ifdef CPTCFG_MAC80211_LEDS
        const char *led_default_trigger;
        struct list_head leds;
+#ifdef CONFIG_GPIOLIB
+       struct ath9k_gpio_chip *gpiochip;
+#endif
 #endif
 
 #ifdef CPTCFG_ATH9K_DEBUGFS
--- a/drivers/net/wireless/ath/ath9k/gpio.c
+++ b/drivers/net/wireless/ath/ath9k/gpio.c
@@ -16,13 +16,139 @@
 
 #include "ath9k.h"
 #include <linux/ath9k_platform.h>
+#include <linux/gpio.h>
+
+#ifdef CPTCFG_MAC80211_LEDS
+
+#ifdef CONFIG_GPIOLIB
+
+/***************/
+/*  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_gpio_request_in(gc->sc->sc_ah, offset, "ath9k-gpio");
+
+       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_gpio_request_out(gc->sc->sc_ah, offset, "ath9k-gpio",
+                                 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 */
+static void ath9k_register_gpio_chip(struct ath_softc *sc)
+{
+       struct ath9k_gpio_chip *gc;
+       struct ath_hw *ah = sc->sc_ah;
+
+       gc = kzalloc(sizeof(struct ath9k_gpio_chip), GFP_KERNEL);
+       if (!gc)
+               return;
+
+       gc->sc = sc;
+       snprintf(gc->label, sizeof(gc->label), "ath9k-%s",
+                wiphy_name(sc->hw->wiphy));
+#ifdef CONFIG_OF
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,5,0)
+       gc->gchip.parent = sc->dev;
+#else
+       gc->gchip.dev = sc->dev;
+#endif
+#endif
+       gc->gchip.label = gc->label;
+       gc->gchip.base = -1;    /* determine base automatically */
+       gc->gchip.ngpio = ah->caps.num_gpio_pins;
+       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;
+
+       if (gpiochip_add(&gc->gchip)) {
+               kfree(gc);
+               return;
+       }
+
+#ifdef CONFIG_OF
+       gc->gchip.owner = NULL;
+#endif
+       sc->gpiochip = gc;
+}
+
+/* remove GPIO chip */
+static 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;
+}
+
+#else /* CONFIG_GPIOLIB */
+
+static inline void ath9k_register_gpio_chip(struct ath_softc *sc)
+{
+}
+
+static inline void ath9k_unregister_gpio_chip(struct ath_softc *sc)
+{
+}
+
+#endif /* CONFIG_GPIOLIB */
 
 /********************************/
 /*      LED functions          */
 /********************************/
 
-#ifdef CPTCFG_MAC80211_LEDS
-
 static void ath_fill_led_pin(struct ath_softc *sc)
 {
        struct ath_hw *ah = sc->sc_ah;
@@ -80,6 +206,12 @@ static int ath_add_led(struct ath_softc
        else
                ath9k_hw_set_gpio(sc->sc_ah, gpio->gpio, gpio->active_low);
 
+#ifdef CONFIG_GPIOLIB
+       /* If there is GPIO chip configured, reserve LED pin */
+       if (sc->gpiochip)
+               gpio_request(sc->gpiochip->gchip.base + gpio->gpio, gpio->name);
+#endif
+
        return 0;
 }
 
@@ -136,17 +268,24 @@ void ath_deinit_leds(struct ath_softc *s
 
        while (!list_empty(&sc->leds)) {
                led = list_first_entry(&sc->leds, struct ath_led, list);
+#ifdef CONFIG_GPIOLIB
+               /* If there is GPIO chip configured, free LED pin */
+               if (sc->gpiochip)
+                       gpio_free(sc->gpiochip->gchip.base + led->gpio->gpio);
+#endif
                list_del(&led->list);
                ath_led_brightness(&led->cdev, LED_OFF);
                led_classdev_unregister(&led->cdev);
                ath9k_hw_gpio_free(sc->sc_ah, led->gpio->gpio);
                kfree(led);
        }
+       ath9k_unregister_gpio_chip(sc);
 }
 
 void ath_init_leds(struct ath_softc *sc)
 {
        struct ath9k_platform_data *pdata = sc->dev->platform_data;
+       struct device_node *np = sc->dev->of_node;
        char led_name[32];
        const char *trigger;
        int i;
@@ -156,6 +295,15 @@ void ath_init_leds(struct ath_softc *sc)
        if (AR_SREV_9100(sc->sc_ah))
                return;
 
+       if (!np)
+               ath9k_register_gpio_chip(sc);
+
+       /* setup gpio controller only if requested and skip the led_pin setup */
+       if (of_property_read_bool(np, "gpio-controller")) {
+               ath9k_register_gpio_chip(sc);
+               return;
+       }
+
        ath_fill_led_pin(sc);
 
        if (pdata && pdata->leds && pdata->num_leds)
@@ -180,6 +328,7 @@ void ath_init_leds(struct ath_softc *sc)
        ath_create_gpio_led(sc, sc->sc_ah->led_pin, led_name, trigger,
                           !sc->sc_ah->config.led_active_high);
 }
+
 #endif
 
 /*******************/