mmc: sdhci: Do not lock spinlock around mmc_gpio_get_ro()

sdhci_check_ro() can call mmc_gpio_get_ro() while holding the sdhci
host->lock spinlock. That would be a problem if the GPIO access done by
mmc_gpio_get_ro() needed to sleep.

However, host->lock is not needed anyway. The mmc core ensures that host
operations do not race with each other, and asynchronous callbacks like the
interrupt handler, software timeouts, completion work etc, cannot affect
sdhci_check_ro().

So remove the locking.

Fixes: 6d5cd068 ("mmc: sdhci: use WP GPIO in sdhci_check_ro()")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240614080051.4005-3-adrian.hunter@intel.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci.c

@@ -2516,11 +2516,8 @@ EXPORT_SYMBOL_GPL(sdhci_get_cd_nogpio);
 static int sdhci_check_ro(struct sdhci_host *host)
 {
 	bool allow_invert = false;
-	unsigned long flags;
 	int is_readonly;
 
-	spin_lock_irqsave(&host->lock, flags);
-
 	if (host->flags & SDHCI_DEVICE_DEAD) {
 		is_readonly = 0;
 	} else if (host->ops->get_ro) {
@@ -2535,8 +2532,6 @@ static int sdhci_check_ro(struct sdhci_host *host)
 		allow_invert = true;
 	}
 
-	spin_unlock_irqrestore(&host->lock, flags);
-
 	if (is_readonly >= 0 &&
 	    allow_invert &&
 	    (host->quirks & SDHCI_QUIRK_INVERTED_WRITE_PROTECT))