When rtsx_pci suspends, the card reader hardware powers off but the sdmmc
driver's prev_power_state remains as MMC_POWER_ON. This causes sd_power_on
to skip reinitialization on the next I/O request, leading to DMA transfer
timeouts and errors on resume 20% of the time.
Add a power_off slot callback so the PCR can notify the sdmmc driver
during suspend. The sdmmc driver resets prev_power_state, and sd_request
checks this to reinitialize the card before the next I/O.
Signed-off-by: Matthew Schwartz <matthew.schwartz@linux.dev>
---
drivers/misc/cardreader/rtsx_pcr.c | 9 +++++++++
drivers/mmc/host/rtsx_pci_sdmmc.c | 22 ++++++++++++++++++++++
include/linux/rtsx_common.h | 1 +
3 files changed, 32 insertions(+)
diff --git a/drivers/misc/cardreader/rtsx_pcr.c b/drivers/misc/cardreader/rtsx_pcr.c
index f9952d76d6ed..f1f4d8ed544d 100644
--- a/drivers/misc/cardreader/rtsx_pcr.c
+++ b/drivers/misc/cardreader/rtsx_pcr.c
@@ -1654,6 +1654,7 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
struct pci_dev *pcidev = to_pci_dev(dev_d);
struct pcr_handle *handle = pci_get_drvdata(pcidev);
struct rtsx_pcr *pcr = handle->pcr;
+ struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
dev_dbg(&(pcidev->dev), "--> %s\n", __func__);
@@ -1661,6 +1662,9 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
mutex_lock(&pcr->pcr_mutex);
+ if (slot->p_dev && slot->power_off)
+ slot->power_off(slot->p_dev);
+
rtsx_pci_power_off(pcr, HOST_ENTER_S3, false);
mutex_unlock(&pcr->pcr_mutex);
@@ -1772,12 +1776,17 @@ static int rtsx_pci_runtime_suspend(struct device *device)
struct pci_dev *pcidev = to_pci_dev(device);
struct pcr_handle *handle = pci_get_drvdata(pcidev);
struct rtsx_pcr *pcr = handle->pcr;
+ struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
dev_dbg(device, "--> %s\n", __func__);
cancel_delayed_work_sync(&pcr->carddet_work);
mutex_lock(&pcr->pcr_mutex);
+
+ if (slot->p_dev && slot->power_off)
+ slot->power_off(slot->p_dev);
+
rtsx_pci_power_off(pcr, HOST_ENTER_S3, true);
mutex_unlock(&pcr->pcr_mutex);
diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
index 792ebae46697..74ee8623ad4e 100644
--- a/drivers/mmc/host/rtsx_pci_sdmmc.c
+++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
@@ -47,6 +47,7 @@ struct realtek_pci_sdmmc {
};
static int sdmmc_init_sd_express(struct mmc_host *mmc, struct mmc_ios *ios);
+static int sd_power_on(struct realtek_pci_sdmmc *host, unsigned char power_mode);
static inline struct device *sdmmc_dev(struct realtek_pci_sdmmc *host)
{
@@ -821,6 +822,15 @@ static void sd_request(struct work_struct *work)
rtsx_pci_start_run(pcr);
+ if (host->prev_power_state == MMC_POWER_OFF) {
+ err = sd_power_on(host, MMC_POWER_ON);
+ if (err) {
+ cmd->error = err;
+ mutex_unlock(&pcr->pcr_mutex);
+ goto finish;
+ }
+ }
+
rtsx_pci_switch_clock(pcr, host->clock, host->ssc_depth,
host->initial_mode, host->double_clk, host->vpclk);
rtsx_pci_write_register(pcr, CARD_SELECT, 0x07, SD_MOD_SEL);
@@ -1524,6 +1534,16 @@ static void rtsx_pci_sdmmc_card_event(struct platform_device *pdev)
mmc_detect_change(host->mmc, 0);
}
+static void rtsx_pci_sdmmc_power_off(struct platform_device *pdev)
+{
+ struct realtek_pci_sdmmc *host = platform_get_drvdata(pdev);
+
+ if (!host)
+ return;
+
+ host->prev_power_state = MMC_POWER_OFF;
+}
+
static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
{
struct mmc_host *mmc;
@@ -1556,6 +1576,7 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, host);
pcr->slots[RTSX_SD_CARD].p_dev = pdev;
pcr->slots[RTSX_SD_CARD].card_event = rtsx_pci_sdmmc_card_event;
+ pcr->slots[RTSX_SD_CARD].power_off = rtsx_pci_sdmmc_power_off;
mutex_init(&host->host_mutex);
@@ -1587,6 +1608,7 @@ static void rtsx_pci_sdmmc_drv_remove(struct platform_device *pdev)
pcr = host->pcr;
pcr->slots[RTSX_SD_CARD].p_dev = NULL;
pcr->slots[RTSX_SD_CARD].card_event = NULL;
+ pcr->slots[RTSX_SD_CARD].power_off = NULL;
mmc = host->mmc;
cancel_work_sync(&host->work);
diff --git a/include/linux/rtsx_common.h b/include/linux/rtsx_common.h
index da9c8c6b5d50..f294f478f0c0 100644
--- a/include/linux/rtsx_common.h
+++ b/include/linux/rtsx_common.h
@@ -32,6 +32,7 @@ struct platform_device;
struct rtsx_slot {
struct platform_device *p_dev;
void (*card_event)(struct platform_device *p_dev);
+ void (*power_off)(struct platform_device *p_dev);
};
#endif
--
2.52.0On Mon, 5 Jan 2026 at 07:02, Matthew Schwartz
<matthew.schwartz@linux.dev> wrote:
>
> When rtsx_pci suspends, the card reader hardware powers off but the sdmmc
> driver's prev_power_state remains as MMC_POWER_ON. This causes sd_power_on
> to skip reinitialization on the next I/O request, leading to DMA transfer
> timeouts and errors on resume 20% of the time.
The mmc core should power-off the card, via the ->set_ios() callback
before the rtsx_pci suspends. In other words, the mmc core should have
set MMC_POWER_OFF.
That said, there seems to be something wrong in
drivers/mmc/host/rtsx_pci_sdmmc.c's ->set_ios(), if that isn't tracked
correctly. The parent device/driver, rtsx_pci should not need to
inform that the power to the card is removed, as that should be known
already by the rtsx_pci_sdmmc driver.
>
> Add a power_off slot callback so the PCR can notify the sdmmc driver
> during suspend. The sdmmc driver resets prev_power_state, and sd_request
> checks this to reinitialize the card before the next I/O.
>
> Signed-off-by: Matthew Schwartz <matthew.schwartz@linux.dev>
> ---
> drivers/misc/cardreader/rtsx_pcr.c | 9 +++++++++
> drivers/mmc/host/rtsx_pci_sdmmc.c | 22 ++++++++++++++++++++++
> include/linux/rtsx_common.h | 1 +
> 3 files changed, 32 insertions(+)
>
> diff --git a/drivers/misc/cardreader/rtsx_pcr.c b/drivers/misc/cardreader/rtsx_pcr.c
> index f9952d76d6ed..f1f4d8ed544d 100644
> --- a/drivers/misc/cardreader/rtsx_pcr.c
> +++ b/drivers/misc/cardreader/rtsx_pcr.c
> @@ -1654,6 +1654,7 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
> struct pci_dev *pcidev = to_pci_dev(dev_d);
> struct pcr_handle *handle = pci_get_drvdata(pcidev);
> struct rtsx_pcr *pcr = handle->pcr;
> + struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
>
> dev_dbg(&(pcidev->dev), "--> %s\n", __func__);
>
> @@ -1661,6 +1662,9 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
>
> mutex_lock(&pcr->pcr_mutex);
>
> + if (slot->p_dev && slot->power_off)
> + slot->power_off(slot->p_dev);
> +
> rtsx_pci_power_off(pcr, HOST_ENTER_S3, false);
>
> mutex_unlock(&pcr->pcr_mutex);
> @@ -1772,12 +1776,17 @@ static int rtsx_pci_runtime_suspend(struct device *device)
> struct pci_dev *pcidev = to_pci_dev(device);
> struct pcr_handle *handle = pci_get_drvdata(pcidev);
> struct rtsx_pcr *pcr = handle->pcr;
> + struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
>
> dev_dbg(device, "--> %s\n", __func__);
>
> cancel_delayed_work_sync(&pcr->carddet_work);
>
> mutex_lock(&pcr->pcr_mutex);
> +
> + if (slot->p_dev && slot->power_off)
> + slot->power_off(slot->p_dev);
> +
> rtsx_pci_power_off(pcr, HOST_ENTER_S3, true);
>
> mutex_unlock(&pcr->pcr_mutex);
> diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
> index 792ebae46697..74ee8623ad4e 100644
> --- a/drivers/mmc/host/rtsx_pci_sdmmc.c
> +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
> @@ -47,6 +47,7 @@ struct realtek_pci_sdmmc {
> };
>
> static int sdmmc_init_sd_express(struct mmc_host *mmc, struct mmc_ios *ios);
> +static int sd_power_on(struct realtek_pci_sdmmc *host, unsigned char power_mode);
>
> static inline struct device *sdmmc_dev(struct realtek_pci_sdmmc *host)
> {
> @@ -821,6 +822,15 @@ static void sd_request(struct work_struct *work)
>
> rtsx_pci_start_run(pcr);
>
> + if (host->prev_power_state == MMC_POWER_OFF) {
> + err = sd_power_on(host, MMC_POWER_ON);
> + if (err) {
> + cmd->error = err;
> + mutex_unlock(&pcr->pcr_mutex);
> + goto finish;
> + }
> + }
> +
> rtsx_pci_switch_clock(pcr, host->clock, host->ssc_depth,
> host->initial_mode, host->double_clk, host->vpclk);
> rtsx_pci_write_register(pcr, CARD_SELECT, 0x07, SD_MOD_SEL);
> @@ -1524,6 +1534,16 @@ static void rtsx_pci_sdmmc_card_event(struct platform_device *pdev)
> mmc_detect_change(host->mmc, 0);
> }
>
> +static void rtsx_pci_sdmmc_power_off(struct platform_device *pdev)
> +{
> + struct realtek_pci_sdmmc *host = platform_get_drvdata(pdev);
> +
> + if (!host)
> + return;
> +
> + host->prev_power_state = MMC_POWER_OFF;
> +}
> +
> static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
> {
> struct mmc_host *mmc;
> @@ -1556,6 +1576,7 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
> platform_set_drvdata(pdev, host);
> pcr->slots[RTSX_SD_CARD].p_dev = pdev;
> pcr->slots[RTSX_SD_CARD].card_event = rtsx_pci_sdmmc_card_event;
> + pcr->slots[RTSX_SD_CARD].power_off = rtsx_pci_sdmmc_power_off;
>
> mutex_init(&host->host_mutex);
>
> @@ -1587,6 +1608,7 @@ static void rtsx_pci_sdmmc_drv_remove(struct platform_device *pdev)
> pcr = host->pcr;
> pcr->slots[RTSX_SD_CARD].p_dev = NULL;
> pcr->slots[RTSX_SD_CARD].card_event = NULL;
> + pcr->slots[RTSX_SD_CARD].power_off = NULL;
> mmc = host->mmc;
>
> cancel_work_sync(&host->work);
> diff --git a/include/linux/rtsx_common.h b/include/linux/rtsx_common.h
> index da9c8c6b5d50..f294f478f0c0 100644
> --- a/include/linux/rtsx_common.h
> +++ b/include/linux/rtsx_common.h
> @@ -32,6 +32,7 @@ struct platform_device;
> struct rtsx_slot {
> struct platform_device *p_dev;
> void (*card_event)(struct platform_device *p_dev);
> + void (*power_off)(struct platform_device *p_dev);
> };
>
> #endif
> --
> 2.52.0
>
Kind regards
Uffe
On 1/20/26 4:41 AM, Ulf Hansson wrote:
> On Mon, 5 Jan 2026 at 07:02, Matthew Schwartz
> <matthew.schwartz@linux.dev> wrote:
>>
>> When rtsx_pci suspends, the card reader hardware powers off but the sdmmc
>> driver's prev_power_state remains as MMC_POWER_ON. This causes sd_power_on
>> to skip reinitialization on the next I/O request, leading to DMA transfer
>> timeouts and errors on resume 20% of the time.
>
> The mmc core should power-off the card, via the ->set_ios() callback
> before the rtsx_pci suspends. In other words, the mmc core should have
> set MMC_POWER_OFF.
>
> That said, there seems to be something wrong in
> drivers/mmc/host/rtsx_pci_sdmmc.c's ->set_ios(), if that isn't tracked
> correctly. The parent device/driver, rtsx_pci should not need to
> inform that the power to the card is removed, as that should be known
> already by the rtsx_pci_sdmmc driver.
Ah, I see what you mean now, I think it should be fixed in rtsx_pci_sdmmc
too.
These already seem to be in char-misc-next, so I think I need to wait
until those hit upstream and then revert as a part of a v2 patch? If I revert
from char-misc-next I'm worried the commit id won't match once it gets merged
into master.
Thanks,
Matt
>
>>
>> Add a power_off slot callback so the PCR can notify the sdmmc driver
>> during suspend. The sdmmc driver resets prev_power_state, and sd_request
>> checks this to reinitialize the card before the next I/O.
>>
>> Signed-off-by: Matthew Schwartz <matthew.schwartz@linux.dev>
>> ---
>> drivers/misc/cardreader/rtsx_pcr.c | 9 +++++++++
>> drivers/mmc/host/rtsx_pci_sdmmc.c | 22 ++++++++++++++++++++++
>> include/linux/rtsx_common.h | 1 +
>> 3 files changed, 32 insertions(+)
>>
>> diff --git a/drivers/misc/cardreader/rtsx_pcr.c b/drivers/misc/cardreader/rtsx_pcr.c
>> index f9952d76d6ed..f1f4d8ed544d 100644
>> --- a/drivers/misc/cardreader/rtsx_pcr.c
>> +++ b/drivers/misc/cardreader/rtsx_pcr.c
>> @@ -1654,6 +1654,7 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
>> struct pci_dev *pcidev = to_pci_dev(dev_d);
>> struct pcr_handle *handle = pci_get_drvdata(pcidev);
>> struct rtsx_pcr *pcr = handle->pcr;
>> + struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
>>
>> dev_dbg(&(pcidev->dev), "--> %s\n", __func__);
>>
>> @@ -1661,6 +1662,9 @@ static int __maybe_unused rtsx_pci_suspend(struct device *dev_d)
>>
>> mutex_lock(&pcr->pcr_mutex);
>>
>> + if (slot->p_dev && slot->power_off)
>> + slot->power_off(slot->p_dev);
>> +
>> rtsx_pci_power_off(pcr, HOST_ENTER_S3, false);
>>
>> mutex_unlock(&pcr->pcr_mutex);
>> @@ -1772,12 +1776,17 @@ static int rtsx_pci_runtime_suspend(struct device *device)
>> struct pci_dev *pcidev = to_pci_dev(device);
>> struct pcr_handle *handle = pci_get_drvdata(pcidev);
>> struct rtsx_pcr *pcr = handle->pcr;
>> + struct rtsx_slot *slot = &pcr->slots[RTSX_SD_CARD];
>>
>> dev_dbg(device, "--> %s\n", __func__);
>>
>> cancel_delayed_work_sync(&pcr->carddet_work);
>>
>> mutex_lock(&pcr->pcr_mutex);
>> +
>> + if (slot->p_dev && slot->power_off)
>> + slot->power_off(slot->p_dev);
>> +
>> rtsx_pci_power_off(pcr, HOST_ENTER_S3, true);
>>
>> mutex_unlock(&pcr->pcr_mutex);
>> diff --git a/drivers/mmc/host/rtsx_pci_sdmmc.c b/drivers/mmc/host/rtsx_pci_sdmmc.c
>> index 792ebae46697..74ee8623ad4e 100644
>> --- a/drivers/mmc/host/rtsx_pci_sdmmc.c
>> +++ b/drivers/mmc/host/rtsx_pci_sdmmc.c
>> @@ -47,6 +47,7 @@ struct realtek_pci_sdmmc {
>> };
>>
>> static int sdmmc_init_sd_express(struct mmc_host *mmc, struct mmc_ios *ios);
>> +static int sd_power_on(struct realtek_pci_sdmmc *host, unsigned char power_mode);
>>
>> static inline struct device *sdmmc_dev(struct realtek_pci_sdmmc *host)
>> {
>> @@ -821,6 +822,15 @@ static void sd_request(struct work_struct *work)
>>
>> rtsx_pci_start_run(pcr);
>>
>> + if (host->prev_power_state == MMC_POWER_OFF) {
>> + err = sd_power_on(host, MMC_POWER_ON);
>> + if (err) {
>> + cmd->error = err;
>> + mutex_unlock(&pcr->pcr_mutex);
>> + goto finish;
>> + }
>> + }
>> +
>> rtsx_pci_switch_clock(pcr, host->clock, host->ssc_depth,
>> host->initial_mode, host->double_clk, host->vpclk);
>> rtsx_pci_write_register(pcr, CARD_SELECT, 0x07, SD_MOD_SEL);
>> @@ -1524,6 +1534,16 @@ static void rtsx_pci_sdmmc_card_event(struct platform_device *pdev)
>> mmc_detect_change(host->mmc, 0);
>> }
>>
>> +static void rtsx_pci_sdmmc_power_off(struct platform_device *pdev)
>> +{
>> + struct realtek_pci_sdmmc *host = platform_get_drvdata(pdev);
>> +
>> + if (!host)
>> + return;
>> +
>> + host->prev_power_state = MMC_POWER_OFF;
>> +}
>> +
>> static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
>> {
>> struct mmc_host *mmc;
>> @@ -1556,6 +1576,7 @@ static int rtsx_pci_sdmmc_drv_probe(struct platform_device *pdev)
>> platform_set_drvdata(pdev, host);
>> pcr->slots[RTSX_SD_CARD].p_dev = pdev;
>> pcr->slots[RTSX_SD_CARD].card_event = rtsx_pci_sdmmc_card_event;
>> + pcr->slots[RTSX_SD_CARD].power_off = rtsx_pci_sdmmc_power_off;
>>
>> mutex_init(&host->host_mutex);
>>
>> @@ -1587,6 +1608,7 @@ static void rtsx_pci_sdmmc_drv_remove(struct platform_device *pdev)
>> pcr = host->pcr;
>> pcr->slots[RTSX_SD_CARD].p_dev = NULL;
>> pcr->slots[RTSX_SD_CARD].card_event = NULL;
>> + pcr->slots[RTSX_SD_CARD].power_off = NULL;
>> mmc = host->mmc;
>>
>> cancel_work_sync(&host->work);
>> diff --git a/include/linux/rtsx_common.h b/include/linux/rtsx_common.h
>> index da9c8c6b5d50..f294f478f0c0 100644
>> --- a/include/linux/rtsx_common.h
>> +++ b/include/linux/rtsx_common.h
>> @@ -32,6 +32,7 @@ struct platform_device;
>> struct rtsx_slot {
>> struct platform_device *p_dev;
>> void (*card_event)(struct platform_device *p_dev);
>> + void (*power_off)(struct platform_device *p_dev);
>> };
>>
>> #endif
>> --
>> 2.52.0
>>
>
> Kind regards
> Uffe
On Tue, 20 Jan 2026 at 19:39, Matthew Schwartz <matthew.schwartz@linux.dev> wrote: > > On 1/20/26 4:41 AM, Ulf Hansson wrote: > > On Mon, 5 Jan 2026 at 07:02, Matthew Schwartz > > <matthew.schwartz@linux.dev> wrote: > >> > >> When rtsx_pci suspends, the card reader hardware powers off but the sdmmc > >> driver's prev_power_state remains as MMC_POWER_ON. This causes sd_power_on > >> to skip reinitialization on the next I/O request, leading to DMA transfer > >> timeouts and errors on resume 20% of the time. > > > > The mmc core should power-off the card, via the ->set_ios() callback > > before the rtsx_pci suspends. In other words, the mmc core should have > > set MMC_POWER_OFF. > > > > That said, there seems to be something wrong in > > drivers/mmc/host/rtsx_pci_sdmmc.c's ->set_ios(), if that isn't tracked > > correctly. The parent device/driver, rtsx_pci should not need to > > inform that the power to the card is removed, as that should be known > > already by the rtsx_pci_sdmmc driver. > > Ah, I see what you mean now, I think it should be fixed in rtsx_pci_sdmmc > too. > > These already seem to be in char-misc-next, so I think I need to wait > until those hit upstream and then revert as a part of a v2 patch? If I revert > from char-misc-next I'm worried the commit id won't match once it gets merged > into master. I have asked Greg to drop them from his misc tree. We should either do that or revert them in his tree. Let's see what he responds. In the meantime, it's perfectly possible to continue working on the issue and please base your patches on top of the mmc tree. [...] Kind regards Uffe
© 2016 - 2026 Red Hat, Inc.