kernel/linux.git/include/linux/mmc/host.h, branch v5.10.258

mmc: core: Initial support for SD express card/host

2026-03-04T12:19:43+00:00

[ Upstream commit ead49373d2916080509f51fc6a4ee8f9bc021b9b ] In the SD specification v7.10 the SD express card has been added. This new type of removable SD card, can be managed via a PCIe/NVMe based interface, while also allowing backwards compatibility towards the legacy SD interface. To keep the backwards compatibility, it's required to start the initialization through the legacy SD interface. If it turns out that the mmc host and the SD card, both supports the PCIe/NVMe interface, then a switch should be allowed. Therefore, let's introduce some basic support for this type of SD cards to the mmc core. The mmc host, should set MMC_CAP2_SD_EXP if it supports this interface and MMC_CAP2_SD_EXP_1_2V, if also 1.2V is supported, as to inform the core about it. To deal with the switch to the PCIe/NVMe interface, the mmc host is required to implement a new host ops, ->init_sd_express(). Based on the initial communication between the host and the card, host->ios.timing is set to either MMC_TIMING_SD_EXP or MMC_TIMING_SD_EXP_1_2V, depending on if 1.2V is supported or not. In this way, the mmc host can check these values in its ->init_sd_express() ops, to know how to proceed with the handover. Note that, to manage card insert/removal, the mmc core sticks with using the ->get_cd() callback, which means it's the host's responsibility to make sure it provides valid data, even if the card may be managed by PCIe/NVMe at the moment. As long as the card seems to be present, the mmc core keeps the card powered on. Cc: Greg Kroah-Hartman Cc: Arnd Bergmann Cc: Christoph Hellwig Cc: Rui Feng Signed-off-by: Ulf Hansson Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/1603936636-3126-1-git-send-email-rui_feng@realsil.com.cn Stable-dep-of: aced969e9bf3 ("mmc: rtsx_pci_sdmmc: increase power-on settling delay to 5ms") Signed-off-by: Sasha Levin

mmc: core: add helpers mmc_regulator_enable/disable_vqmmc

2023-12-08T07:46:16+00:00

[ Upstream commit 8d91f3f8ae57e6292142ca89f322e90fa0d6ac02 ] There's a number of drivers (e.g. dw_mmc, meson-gx, mmci, sunxi) using the same mechanism and a private flag vqmmc_enabled to deal with enabling/disabling the vqmmc regulator. Move this to the core and create new helpers mmc_regulator_enable_vqmmc and mmc_regulator_disable_vqmmc. Signed-off-by: Heiner Kallweit Acked-by: Martin Blumenstingl Link: https://lore.kernel.org/r/71586432-360f-9b92-17f6-b05a8a971bc2@gmail.com Signed-off-by: Ulf Hansson Stable-dep-of: 477865af60b2 ("mmc: sdhci-sprd: Fix vqmmc not shutting down after the card was pulled") Signed-off-by: Sasha Levin

mmc: core: add devm_mmc_alloc_host

2023-08-26T13:26:49+00:00

[ Upstream commit 80df83c2c57e75cb482ccf0c639ce84703ab41a2 ] Add a device-managed version of mmc_alloc_host(). The argument order is reversed compared to mmc_alloc_host() because device-managed functions typically have the device argument first. Signed-off-by: Heiner Kallweit Link: https://lore.kernel.org/r/6d8f9fdc-7c9e-8e4f-e6ef-5470b971c74e@gmail.com Signed-off-by: Ulf Hansson Stable-dep-of: b8ada54fa1b8 ("mmc: meson-gx: fix deferred probing") Signed-off-by: Sasha Levin

mmc: core: Fix hanging on I/O during system suspend for removable cards

2021-05-11T12:47:14+00:00

commit 17a17bf50612e6048a9975450cf1bd30f93815b5 upstream. The mmc core uses a PM notifier to temporarily during system suspend, turn off the card detection mechanism for removal/insertion of (e)MMC/SD/SDIO cards. Additionally, the notifier may be used to remove an SDIO card entirely, if a corresponding SDIO functional driver don't have the system suspend/resume callbacks assigned. This behaviour has been around for a very long time. However, a recent bug report tells us there are problems with this approach. More precisely, when receiving the PM_SUSPEND_PREPARE notification, we may end up hanging on I/O to be completed, thus also preventing the system from getting suspended. In the end what happens, is that the cancel_delayed_work_sync() in mmc_pm_notify() ends up waiting for mmc_rescan() to complete - and since mmc_rescan() wants to claim the host, it needs to wait for the I/O to be completed first. Typically, this problem is triggered in Android, if there is ongoing I/O while the user decides to suspend, resume and then suspend the system again. This due to that after the resume, an mmc_rescan() work gets punted to the workqueue, which job is to verify that the card remains inserted after the system has resumed. To fix this problem, userspace needs to become frozen to suspend the I/O, prior to turning off the card detection mechanism. Therefore, let's drop the PM notifiers for mmc subsystem altogether and rely on the card detection to be turned off/on as a part of the system_freezable_wq, that we are already using. Moreover, to allow and SDIO card to be removed during system suspend, let's manage this from a ->prepare() callback, assigned at the mmc_host_class level. In this way, we can use the parent device (the mmc_host_class device), to remove the card device that is the child, in the device_prepare() phase. Reported-by: Kiwoong Kim Cc: stable@vger.kernel.org # v4.5+ Signed-off-by: Ulf Hansson Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20210310152900.149380-1-ulf.hansson@linaro.org Reviewed-by: Kiwoong Kim Signed-off-by: Greg Kroah-Hartman

mmc: core: add a 'doing_init_tune' flag and a 'mmc_doing_tune' helper

2020-09-07T07:16:31+00:00

Our driver needs to know when tuning is in progress. 'doing_retune' only covers re-tuning, not the initial tuning. Add another flag to detect the initial tuning state and add a helper which tells us if any kind of tuning is going on. Only implemented for MMC currently because that's where we need it. SD can be added later if it becomes necessary. Signed-off-by: Wolfram Sang Reviewed-by: Yoshihiro Shimoda Tested-by: Yoshihiro Shimoda Link: https://lore.kernel.org/r/20200901150250.26236-3-wsa+renesas@sang-engineering.com Signed-off-by: Ulf Hansson

mmc: core: Improve documentation of MMC_CAP_HW_RESET

2020-09-07T07:11:29+00:00

MMC_CAP_HW_RESET means that the controller is capable of resetting the eMMC device via RST_n signal, not a reset of the controller. Two drivers got this wrong, so let's make it more clear. Signed-off-by: Wolfram Sang Link: https://lore.kernel.org/r/20200821063533.3771-1-wsa+renesas@sang-engineering.com Signed-off-by: Ulf Hansson

mmc: core: Add MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND

2020-07-13T10:18:26+00:00

The commit 5a36d6bcdf23 ("mmc: core: Add DT-bindings for MMC_CAP2_FULL_PWR_CYCLE") added the "full-pwr-cycle" property which is possible to perform a full power cycle of the card at any time. However, some environment (like r8a77951-salvator-xs) is possible to perform a full power cycle of the card in suspend via firmware (PSCI on arm-trusted-firmware). So, in worst case, since we are not doing a graceful shutdown of the eMMC device (just cut VCCQ while the eMMC is "sleeping") in suspend, it could lead to internal data corruptions. So, add MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND to do a graceful shutdown which issues Power Off notification before entering system suspend. Signed-off-by: Yoshihiro Shimoda Link: https://lore.kernel.org/r/1594123122-13156-3-git-send-email-yoshihiro.shimoda.uh@renesas.com Signed-off-by: Ulf Hansson

mmc: core: Always allow the card detect uevent to be consumed

2020-07-13T10:18:22+00:00

The approach to allow userspace ~5s to consume the uevent, which is triggered when a new card is inserted/initialized, currently requires the mmc host to support system wakeup. This is unnecessary limiting, especially for an mmc host that relies on a GPIO IRQ for card detect. More precisely, the mmc host may not support system wakeup for its corresponding struct device, while the GPIO IRQ still could be configured as a wakeup IRQ via enable_irq_wake(). To support all various cases, let's simply drop the need for the wakeup support. Instead let's always register a wakeup source and activate it for all card detect IRQs by calling __pm_wakeup_event(). Signed-off-by: Ulf Hansson Link: https://lore.kernel.org/r/20200529102341.12529-1-ulf.hansson@linaro.org

mmc: host: Drop redundant MMC_CAP_ERASE

2020-05-28T09:22:14+00:00

The MMC_CAP_ERASE bit is no longer used by the mmc core as erase, discard and trim operations are now always supported. Therefore, drop the bit and move all mmc hosts away from using it. Signed-off-by: Ulf Hansson Reviewed-by: Rui Miguel Silva Link: https://lore.kernel.org/r/20200508112902.23575-1-ulf.hansson@linaro.org Reviewed-by: Linus Walleij

mmc: host: Introduce the request_atomic() for the host

2020-05-28T09:20:59+00:00

The SD host controller can process one request in the atomic context if the card is nonremovable, which means we can submit next request in the irq hard handler when using the MMC host software queue to reduce the latency. Thus this patch adds a new API request_atomic() for the host controller, as well as adding support for host software queue to submit a request by the new request_atomic() API. Moreover there is an unusual case that the card is busy when trying to send a command, and we can not polling the card status in interrupt context by using request_atomic() to dispatch requests. Thus we should queue a work to try again in the non-atomic context in case the host releases the busy signal later. Suggested-by: Adrian Hunter Acked-by: Adrian Hunter Signed-off-by: Baolin Wang Link: https://lore.kernel.org/r/a344e27e506cb2329073cbd5cf65e15cc3cbeba9.1586744073.git.baolin.wang7@gmail.com Signed-off-by: Ulf Hansson