ath9k: fix sleeping in atomic context

The problem is that gpio_free() can sleep and the cfg_soc() can be
called with spinlocks held. One problematic call tree is:

--> ath_reset_internal() takes &sc->sc_pcu_lock spin lock
   --> ath9k_hw_reset()
      --> ath9k_hw_gpio_request_in()
         --> ath9k_hw_gpio_request()
            --> ath9k_hw_gpio_cfg_soc()

Remove gpio_free(), use error message instead, so we should make sure
there is no GPIO conflict.

Also remove ath9k_hw_gpio_free() from ath9k_hw_apply_gpio_override(),
as gpio_mask will never be set for SOC chips.

Signed-off-by: Miaoqing Pan <miaoqing@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1628481916-15030-1-git-send-email-miaoqing@codeaurora.org

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 2ca3b86..172081f 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1621,7 +1621,6 @@ static void ath9k_hw_apply_gpio_override(struct ath_hw *ah)
                ath9k_hw_gpio_request_out(ah, i, NULL,
                                          AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
                ath9k_hw_set_gpio(ah, i, !!(ah->gpio_val & BIT(i)));
-               ath9k_hw_gpio_free(ah, i);
        }
 }
 
@@ -2728,14 +2727,17 @@ static void ath9k_hw_gpio_cfg_output_mux(struct ath_hw *ah, u32 gpio, u32 type)
 static void ath9k_hw_gpio_cfg_soc(struct ath_hw *ah, u32 gpio, bool out,
                                  const char *label)
 {
+       int err;
+
        if (ah->caps.gpio_requested & BIT(gpio))
                return;
 
-       /* may be requested by BSP, free anyway */
-       gpio_free(gpio);
-
-       if (gpio_request_one(gpio, out ? GPIOF_OUT_INIT_LOW : GPIOF_IN, label))
+       err = gpio_request_one(gpio, out ? GPIOF_OUT_INIT_LOW : GPIOF_IN, label);
+       if (err) {
+               ath_err(ath9k_hw_common(ah), "request GPIO%d failed:%d\n",
+                       gpio, err);
                return;
+       }
 
        ah->caps.gpio_requested |= BIT(gpio);
 }