[PATCH v4] mmc: Poll CD in case cyclic framework is enabled

[Marek Vasut]

In case the cyclic framework is enabled, poll the card detect of already
initialized cards and deinitialize them in case they are removed. Since
the card initialization is a longer process and card initialization is
done on first access to an uninitialized card anyway, avoid initializing
newly detected uninitialized cards in the cyclic callback.

Signed-off-by: Marek Vasut <marek.vasut+rene...@mailbox.org>
---
Cc: Jaehoon Chung <jh80.ch...@samsung.com>
Cc: Peng Fan <peng....@nxp.com>
Cc: Simon Glass <s...@chromium.org>
---
V2: Move the cyclic registration/unregistration into mmc init/deinit
V3: Replace if (CONFIG_IS_ENABLED(CYCLIC)...) with #if as the former
    does not work with structure members
V4: Stuff the code with CONFIG_IS_ENABLED() variants to avoid #ifdefs
---
 drivers/mmc/mmc.c | 32 ++++++++++++++++++++++++++++++++
 include/mmc.h     |  3 +++
 2 files changed, 35 insertions(+)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index eb5010c1465..e90ffd5dcd1 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -2985,6 +2985,20 @@ static int mmc_complete_init(struct mmc *mmc)
        return err;
 }
 
+static void __maybe_unused mmc_cyclic_cd_poll(void *ctx)
+{
+       struct mmc *m = ctx;
+
+       if (!m->has_init)
+               return;
+
+       if (mmc_getcd(m))
+               return;
+
+       mmc_deinit(m);
+       m->has_init = 0;
+}
+
 int mmc_init(struct mmc *mmc)
 {
        int err = 0;
@@ -3007,6 +3021,19 @@ int mmc_init(struct mmc *mmc)
        if (err)
                pr_info("%s: %d, time %lu\n", __func__, err, get_timer(start));
 
+       if (CONFIG_IS_ENABLED(CYCLIC, (!mmc->cyclic), (NULL))) {
+               /* Register cyclic function for card detect polling */
+               CONFIG_IS_ENABLED(CYCLIC,
+                       (mmc->cyclic = cyclic_register(mmc_cyclic_cd_poll,
+                                                      100 * 1000,
+                                                      mmc->cfg->name, mmc)));
+               if (CONFIG_IS_ENABLED(CYCLIC, (!mmc->cyclic), (NULL))) {
+                       printf("Failed to register %s CD poll function\n",
+                              mmc->cfg->name);
+                       err = -EINVAL;
+               }
+       }
+
        return err;
 }
 
@@ -3014,6 +3041,11 @@ int mmc_deinit(struct mmc *mmc)
 {
        u32 caps_filtered;
 
+       if (CONFIG_IS_ENABLED(CYCLIC, (mmc->cyclic), (NULL))) {
+               cyclic_unregister(CONFIG_IS_ENABLED(CYCLIC, (mmc->cyclic), 
NULL));
+               CONFIG_IS_ENABLED(CYCLIC, (mmc->cyclic = NULL));
+       }
+
        if (!CONFIG_IS_ENABLED(MMC_UHS_SUPPORT) &&
            !CONFIG_IS_ENABLED(MMC_HS200_SUPPORT) &&
            !CONFIG_IS_ENABLED(MMC_HS400_SUPPORT))
diff --git a/include/mmc.h b/include/mmc.h
index 1022db3ffa7..706566fa1ad 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -14,6 +14,7 @@
 #include <linux/sizes.h>
 #include <linux/compiler.h>
 #include <linux/dma-direction.h>
+#include <cyclic.h>
 #include <part.h>
 
 struct bd_info;
@@ -739,6 +740,8 @@ struct mmc {
        u8 hs400_tuning;
 
        enum bus_mode user_speed_mode; /* input speed mode from user */
+
+       CONFIG_IS_ENABLED(CYCLIC, (struct cyclic_info *cyclic));
 };
 
 #if CONFIG_IS_ENABLED(DM_MMC)
-- 
2.43.0