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ath9k: fix sleeping in atomic context

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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
This commit is contained in:
Miaoqing Pan 2021-08-09 12:05:16 +08:00 committed by Kalle Valo
parent 23151b9ae7
commit 7c48662b9d
1 changed files with 7 additions and 5 deletions
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12
drivers/net/wireless/ath/ath9k/hw.c
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@ -1621,7 +1621,6 @@ static void ath9k_hw_apply_gpio_override(struct ath_hw *ah)
ath9k_hw_gpio_request_out(ah, i, NULL, ath9k_hw_gpio_request_out(ah, i, NULL,
AR_GPIO_OUTPUT_MUX_AS_OUTPUT); AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
ath9k_hw_set_gpio(ah, i, !!(ah->gpio_val & BIT(i))); 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, static void ath9k_hw_gpio_cfg_soc(struct ath_hw *ah, u32 gpio, bool out,
const char *label) const char *label)
{ {
int err;
if (ah->caps.gpio_requested & BIT(gpio)) if (ah->caps.gpio_requested & BIT(gpio))
return; return;
/* may be requested by BSP, free anyway */ err = gpio_request_one(gpio, out ? GPIOF_OUT_INIT_LOW : GPIOF_IN, label);
gpio_free(gpio); if (err) {
ath_err(ath9k_hw_common(ah), "request GPIO%d failed:%d\n",
if (gpio_request_one(gpio, out ? GPIOF_OUT_INIT_LOW : GPIOF_IN, label)) gpio, err);
return; return;
}
ah->caps.gpio_requested |= BIT(gpio); ah->caps.gpio_requested |= BIT(gpio);
} }