mmc: sdhci: Do not invert write-protect twice

mmc_of_parse() reads device property "wp-inverted" and sets
MMC_CAP2_RO_ACTIVE_HIGH if it is true. MMC_CAP2_RO_ACTIVE_HIGH is used
to invert a write-protect (AKA read-only) GPIO value.

sdhci_get_property() also reads "wp-inverted" and sets
SDHCI_QUIRK_INVERTED_WRITE_PROTECT which is used to invert the
write-protect value as well but also acts upon a value read out from the
SDHCI_PRESENT_STATE register.

Many drivers call both mmc_of_parse() and sdhci_get_property(),
so that both MMC_CAP2_RO_ACTIVE_HIGH and
SDHCI_QUIRK_INVERTED_WRITE_PROTECT will be set if the controller has
device property "wp-inverted".

Amend the logic in sdhci_check_ro() to allow for that possibility,
so that the write-protect value is not inverted twice.

Also do not invert the value if it is a negative error value. Note that
callers treat an error the same as not-write-protected, so the result is
functionally the same in that case.

Also do not invert the value if sdhci host operation ->get_ro() is used.
None of the users of that callback set SDHCI_QUIRK_INVERTED_WRITE_PROTECT
directly or indirectly, but two do call mmc_gpio_get_ro(), so leave it to
them to deal with that if they ever set SDHCI_QUIRK_INVERTED_WRITE_PROTECT
in the future.

Fixes: 6d5cd068ee59 ("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/20240614080051.4005-2-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 746f4cf7ab03380c3860bc7d028c3c89cb784789..81b81d7bb3d81bf51258b077ca150d9dccf97491 100644 (file)
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2515,26 +2515,34 @@ 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)
+       if (host->flags & SDHCI_DEVICE_DEAD) {
                is_readonly = 0;
-       else if (host->ops->get_ro)
+       } else if (host->ops->get_ro) {
                is_readonly = host->ops->get_ro(host);
-       else if (mmc_can_gpio_ro(host->mmc))
+       } else if (mmc_can_gpio_ro(host->mmc)) {
                is_readonly = mmc_gpio_get_ro(host->mmc);
-       else
+               /* Do not invert twice */
+               allow_invert = !(host->mmc->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
+       } else {
                is_readonly = !(sdhci_readl(host, SDHCI_PRESENT_STATE)
                                & SDHCI_WRITE_PROTECT);
+               allow_invert = true;
+       }
 
        spin_unlock_irqrestore(&host->lock, flags);
 
-       /* This quirk needs to be replaced by a callback-function later */
-       return host->quirks & SDHCI_QUIRK_INVERTED_WRITE_PROTECT ?
-               !is_readonly : is_readonly;
+       if (is_readonly >= 0 &&
+           allow_invert &&
+           (host->quirks & SDHCI_QUIRK_INVERTED_WRITE_PROTECT))
+               is_readonly = !is_readonly;
+
+       return is_readonly;
 }
 
 #define SAMPLE_COUNT   5