* [PATCH V1 1/1] mmc: sdio: Export an API to reinit the SDIO card
2025-07-21 9:43 [PATCH V1 0/1] Export an API to reinit SDIO card Sayali Lokhande
@ 2025-07-21 9:43 ` Sayali Lokhande
2025-07-22 5:55 ` Christoph Hellwig
2025-07-23 10:25 ` [PATCH V1 0/1] Export an API to reinit " Ulf Hansson
1 sibling, 1 reply; 4+ messages in thread
From: Sayali Lokhande @ 2025-07-21 9:43 UTC (permalink / raw)
To: ulf.hansson, wsa+renesas, avri.altman, adrian.hunter, shawn.lin
Cc: linux-mmc, linux-kernel
Some SDIO client drivers, manage external power to the SDIO card.
In such cases, the card may be power-cycled independently of the
MMC core's runtime PM state.
Currently, reinitialization of the SDIO card is tied to the runtime
PM resume path. However, if the card is powered off and on again before
the autosuspend delay expires, the runtime suspend/resume callbacks are
not triggered, leaving the card in an uninitialized state.
To address this, export sdio_reinit_card() so that client drivers can
explicitly trigger reinitialization after powering the card back on,
ensuring proper device state regardless of runtime PM behavior.
This change enables more robust handling of power-managed SDIO devices
in scenarios where runtime PM is disabled or insufficient.
Signed-off-by: Sayali Lokhande <quic_sayalil@quicinc.com>
---
drivers/mmc/core/core.h | 1 +
drivers/mmc/core/sdio.c | 2 +-
drivers/mmc/core/sdio_io.c | 6 ++++++
include/linux/mmc/sdio_func.h | 2 ++
4 files changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 622085cd766f..737584fafd7a 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -147,6 +147,7 @@ static inline void mmc_claim_host(struct mmc_host *host)
__mmc_claim_host(host, NULL, NULL);
}
+int mmc_sdio_reinit_card(struct mmc_host *host);
int mmc_cqe_start_req(struct mmc_host *host, struct mmc_request *mrq);
void mmc_cqe_post_req(struct mmc_host *host, struct mmc_request *mrq);
int mmc_cqe_recovery(struct mmc_host *host);
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index 0f753367aec1..fc3dda1a67c8 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -911,7 +911,7 @@ static int mmc_sdio_init_card(struct mmc_host *host, u32 ocr,
return err;
}
-static int mmc_sdio_reinit_card(struct mmc_host *host)
+int mmc_sdio_reinit_card(struct mmc_host *host)
{
int ret;
diff --git a/drivers/mmc/core/sdio_io.c b/drivers/mmc/core/sdio_io.c
index b774bf51981d..eae2fb361ec2 100644
--- a/drivers/mmc/core/sdio_io.c
+++ b/drivers/mmc/core/sdio_io.c
@@ -812,3 +812,9 @@ void sdio_retune_release(struct sdio_func *func)
mmc_retune_release(func->card->host);
}
EXPORT_SYMBOL_GPL(sdio_retune_release);
+
+int sdio_reinit_card(struct mmc_host *host)
+{
+ return mmc_sdio_reinit_card(host);
+}
+EXPORT_SYMBOL_GPL(sdio_reinit_card);
diff --git a/include/linux/mmc/sdio_func.h b/include/linux/mmc/sdio_func.h
index fed1f5f4a8d3..f33d0512b6a6 100644
--- a/include/linux/mmc/sdio_func.h
+++ b/include/linux/mmc/sdio_func.h
@@ -12,6 +12,7 @@
#include <linux/mod_devicetable.h>
#include <linux/mmc/pm.h>
+#include <linux/mmc/host.h>
struct mmc_card;
struct sdio_func;
@@ -132,6 +133,7 @@ extern void sdio_release_host(struct sdio_func *func);
extern int sdio_enable_func(struct sdio_func *func);
extern int sdio_disable_func(struct sdio_func *func);
+extern int sdio_reinit_card(struct mmc_host *host);
extern int sdio_set_block_size(struct sdio_func *func, unsigned blksz);
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH V1 0/1] Export an API to reinit SDIO card
2025-07-21 9:43 [PATCH V1 0/1] Export an API to reinit SDIO card Sayali Lokhande
2025-07-21 9:43 ` [PATCH V1 1/1] mmc: sdio: Export an API to reinit the " Sayali Lokhande
@ 2025-07-23 10:25 ` Ulf Hansson
1 sibling, 0 replies; 4+ messages in thread
From: Ulf Hansson @ 2025-07-23 10:25 UTC (permalink / raw)
To: Sayali Lokhande
Cc: wsa+renesas, avri.altman, adrian.hunter, shawn.lin, linux-mmc,
linux-kernel
On Mon, 21 Jul 2025 at 11:43, Sayali Lokhande <quic_sayalil@quicinc.com> wrote:
>
> Some SDIO client drivers, manage external power to the SDIO card.
> In such cases, the card may be power-cycled independently of the
> MMC core's runtime PM state.
> Currently, reinitialization of the SDIO card is tied to the runtime
> PM resume path. However, if the card is powered off and on again before
> the autosuspend delay expires, the runtime suspend/resume callbacks are
> not triggered, leaving the card in an uninitialized state.
>
> To address this, export sdio_reinit_card() so that client drivers can
> explicitly trigger reinitialization after powering the card back on,
> ensuring proper device state regardless of runtime PM behavior.
>
> This change enables more robust handling of power-managed SDIO devices
> in scenarios where runtime PM is disabled or insufficient.
Please use mmc_hw|sw_reset() instead.
Kind regards
Uffe
>
> Sayali Lokhande (1):
> mmc: sdio: Export an API to reinit the SDIO card
>
> drivers/mmc/core/core.h | 1 +
> drivers/mmc/core/sdio.c | 2 +-
> drivers/mmc/core/sdio_io.c | 6 ++++++
> include/linux/mmc/sdio_func.h | 2 ++
> 4 files changed, 10 insertions(+), 1 deletion(-)
>
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> a Linux Foundation Collaborative Project
>
^ permalink raw reply [flat|nested] 4+ messages in thread