We want SDIO drivers to be able to temporarily stop retuning when the
driver knows that the SDIO card is not in a state where retuning will
work (maybe because the card is asleep). We'll move the relevant
functions to a place where drivers can call them.
Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
---
Changes in v4:
- Moved retune hold/release to SDIO API (Adrian).
Changes in v3:
- ("mmc: core: Export mmc_retune_hold_now() mmc_retune_release()") new for v3.
Changes in v2: None
drivers/mmc/core/sdio_io.c | 40 +++++++++++++++++++++++++++++++++++
include/linux/mmc/sdio_func.h | 3 +++
2 files changed, 43 insertions(+)
diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c
index f822a9630b0e..1b6fe737bd72 100644
--- a/drivers/mmc/core/sdio_io.c
+++ b/drivers/mmc/core/sdio_io.c
@@ -15,6 +15,7 @@
#include "sdio_ops.h"
#include "core.h"
#include "card.h"
+#include "host.h"
/**
* sdio_claim_host - exclusively claim a bus for a certain SDIO function
@@ -770,3 +771,42 @@ void sdio_retune_crc_enable(struct sdio_func *func)
func->card->host->retune_crc_disable = false;
}
EXPORT_SYMBOL_GPL(sdio_retune_crc_enable);
+
+/**
+ * sdio_retune_hold_now - start deferring retuning requests till release
+ * @func: SDIO function attached to host
+ *
+ * This function can be called if it's currently a bad time to do
+ * a retune of the SDIO card. Retune requests made during this time
+ * will be held and we'll actually do the retune sometime after the
+ * release.
+ *
+ * This function could be useful if an SDIO card is in a power state
+ * where it can respond to a small subset of commands that doesn't
+ * include the retuning command. Care should be taken when using
+ * this function since (presumably) the retuning request we might be
+ * deferring was made for a good reason.
+ *
+ * This function should be called while the host is claimed.
+ */
+void sdio_retune_hold_now(struct sdio_func *func)
+{
+ mmc_retune_hold_now(func->card->host);
+}
+EXPORT_SYMBOL_GPL(sdio_retune_hold_now);
+
+/**
+ * sdio_retune_release - signal that it's OK to retune now
+ * @func: SDIO function attached to host
+ *
+ * This is the complement to sdio_retune_hold_now(). Calling this
+ * function won't make a retune happen right away but will allow
+ * them to be scheduled normally.
+ *
+ * This function should be called while the host is claimed.
+ */
+void sdio_retune_release(struct sdio_func *func)
+{
+ mmc_retune_release(func->card->host);
+}
+EXPORT_SYMBOL_GPL(sdio_retune_release);
diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index 4820e6d09dac..5a177f7a83c3 100644
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -170,4 +170,7 @@ extern int sdio_set_host_pm_flags(struct sdio_func *func, mmc_pm_flag_t flags);
extern void sdio_retune_crc_disable(struct sdio_func *func);
extern void sdio_retune_crc_enable(struct sdio_func *func);
+extern void sdio_retune_hold_now(struct sdio_func *func);
+extern void sdio_retune_release(struct sdio_func *func);
+
#endif /* LINUX_MMC_SDIO_FUNC_H */
--
2.22.0.rc2.383.gf4fbbf30c2-goog
