Commit 88a4ed85 authored Aug 09, 2021 by Miaoqing Pan Committed by Greg Kroah-Hartman Sep 22, 2021

ath9k: fix sleeping in atomic context



[ Upstream commit 7c48662b9d56666219f526a71ace8c15e6e12f1f ]

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


Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 99b950d5

drivers/net/wireless/ath/ath9k/hw.c

+7 −5

Original line number	Diff line number	Diff line
		@@ -1622,7 +1622,6 @@ 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);
		}
		}

		@@ -2730,14 +2729,17 @@ 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);
		}