[PATCH 6/7] ath9k: Allow using the reset API for the external reset

[Alban]

From: Alban Bedel <al...@free.fr>

Allow using the reset API instead of a platform specific callback to
reset the device.

Signed-off-by: Alban Bedel <al...@free.fr>
---
 drivers/net/wireless/ath/ath9k/hw.c   | 26 +++++++++++++++++++++-----
 drivers/net/wireless/ath/ath9k/hw.h   |  1 +
 drivers/net/wireless/ath/ath9k/init.c | 10 ++++++++++
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/hw.c 
b/drivers/net/wireless/ath/ath9k/hw.c
index 8c5c2dd..efc0435 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -21,6 +21,7 @@
 #include <linux/bitops.h>
 #include <linux/etherdevice.h>
 #include <linux/gpio.h>
+#include <linux/reset.h>
 #include <asm/unaligned.h>
 
 #include "hw.h"
@@ -551,6 +552,24 @@ static int ath9k_hw_attach_ops(struct ath_hw *ah)
        return 0;
 }
 
+static int ath9k_hw_external_reset(struct ath_hw *ah)
+{
+       int ret = 0;
+
+       ath_dbg(ath9k_hw_common(ah), RESET,
+               "reset MAC via external reset\n");
+
+       if (ah->external_reset) {
+               ret = ah->external_reset();
+       } else if (ah->reset) {
+               ret = reset_control_assert(ah->reset);
+               if (!ret)
+                       ret = reset_control_deassert(ah->reset);
+       }
+
+       return ret;
+}
+
 /* Called for all hardware families */
 static int __ath9k_hw_init(struct ath_hw *ah)
 {
@@ -1286,14 +1305,11 @@ static bool ath9k_hw_ar9330_reset_war(struct ath_hw 
*ah, int type)
                        break;
        }
 
-       if (ah->external_reset &&
+       if ((ah->reset || ah->external_reset) &&
            (npend || type == ATH9K_RESET_COLD)) {
                int reset_err = 0;
 
-               ath_dbg(ath9k_hw_common(ah), RESET,
-                       "reset MAC via external reset\n");
-
-               reset_err = ah->external_reset();
+               reset_err = ath9k_hw_external_reset(ah);
                if (reset_err) {
                        ath_err(ath9k_hw_common(ah),
                                "External reset failed, err=%d\n",
diff --git a/drivers/net/wireless/ath/ath9k/hw.h 
b/drivers/net/wireless/ath/ath9k/hw.h
index 7f17c2a..53b67e3 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -966,6 +966,7 @@ struct ath_hw {
        bool is_clk_25mhz;
        int (*get_mac_revision)(void);
        int (*external_reset)(void);
+       struct reset_control *reset;
        bool disable_2ghz;
        bool disable_5ghz;
 
diff --git a/drivers/net/wireless/ath/ath9k/init.c 
b/drivers/net/wireless/ath/ath9k/init.c
index 5cb9c61..f1cb806 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -25,6 +25,7 @@
 #include <linux/nvmem-consumer.h>
 #include <linux/relay.h>
 #include <linux/clk.h>
+#include <linux/reset.h>
 #include <net/ieee80211_radiotap.h>
 
 #include "ath9k.h"
@@ -697,6 +698,15 @@ static int ath9k_init_softc(u16 devid, struct ath_softc 
*sc,
        if (!is_valid_ether_addr(common->macaddr))
                ath9k_get_nvmem_address(sc);
 
+       /* Try to get a reset controller */
+       ah->reset = devm_reset_control_get_optional(sc->dev, NULL);
+       if (IS_ERR(ah->reset)) {
+               if (PTR_ERR(ah->reset) != -ENOENT &&
+                   PTR_ERR(ah->reset) != -ENOTSUPP)
+                       return PTR_ERR(ah->reset);
+               ah->reset = NULL;
+       }
+
        /* If the EEPROM hasn't been retrieved via firmware request
         * use the nvmem API insted.
         */
-- 
2.7.4