kernel.git/include/linux/mmc/host.h, branch linux-5.1.y

mmc: core: API to temporarily disable retuning for SDIO CRC errors

2019-06-25T03:34:44Z

commit 0a55f4ab9678413a01e740c86e9367ba0c612b36 upstream. Normally when the MMC core sees an "-EILSEQ" error returned by a host controller then it will trigger a retuning of the card. This is generally a good idea. However, if a command is expected to sometimes cause transfer errors then these transfer errors shouldn't cause a re-tuning. This re-tuning will be a needless waste of time. One example case where a transfer is expected to cause errors is when transitioning between idle (sometimes referred to as "sleep" in Broadcom code) and active state on certain Broadcom WiFi SDIO cards. Specifically if the card was already transitioning between states when the command was sent it could cause an error on the SDIO bus. Let's add an API that the SDIO function drivers can call that will temporarily disable the auto-tuning functionality. Then we can add a call to this in the Broadcom WiFi driver and any other driver that might have similar needs. NOTE: this makes the assumption that the card is already tuned well enough that it's OK to disable the auto-retuning during one of these error-prone situations. Presumably the driver code performing the error-prone transfer knows how to recover / retry from errors. ...and after we can get back to a state where transfers are no longer error-prone then we can enable the auto-retuning again. If we truly find ourselves in a case where the card needs to be retuned sometimes to handle one of these error-prone transfers then we can always try a few transfers first without auto-retuning and then re-try with auto-retuning if the first few fail. Without this change on rk3288-veyron-minnie I periodically see this in the logs of a machine just sitting there idle: dwmmc_rockchip ff0d0000.dwmmc: Successfully tuned phase to XYZ Cc: stable@vger.kernel.org #v4.18+ Signed-off-by: Douglas Anderson Acked-by: Adrian Hunter Acked-by: Kalle Valo Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

mmc: core: Convert mmc_regulator_get_ocrmask() to static

2019-02-25T14:20:58Z

The only left user of mmc_regulator_get_ocrmask() is the mmc core itself. Therefore, let's drop the export and turn it into static. Signed-off-by: Ulf Hansson

mmc: core: Move regulator helpers to separate file

2019-02-25T14:20:58Z

The mmc regulator helper functions, are placed in the extensive core.c file. In a step towards trying to create a better structure of files, avoiding too many lines of code per file, let's move these helpers to a new file, regulator.c. Moreover, this within this context it makes sense to also drop the export of mmc_vddrange_to_ocrmask(), but instead let's make it internal to the mmc core. Signed-off-by: Ulf Hansson

mmc: bcm2835: Drop pointer to mmc_host from bcm2835_host

2019-02-25T07:40:58Z

The BCM2835 MMC host driver uses a pointer to get from the private bcm2835_host structure to the generic mmc_host structure. However the latter is always immediately preceding the former in memory, so compute its address with a subtraction (which is cheaper than a dereference) and drop the superfluous pointer. No functional change intended. Signed-off-by: Lukas Wunner Cc: Frank Pavlic Cc: Alexander Graf Reviewed-by: Alexander Graf Signed-off-by: Ulf Hansson

mmc: core: Introduce MMC_CAP_SYNC_RUNTIME_PM

2018-12-17T07:26:24Z

To allow mmc host drivers to inform the mmc core about rather using pm_runtime_put_sync_suspend() instead of pm_runtime_put_autosuspend(), let's introduce MMC_CAP_SYNC_RUNTIME_PM. This is especially useful for those mmc host drivers that don't benefit from using the runtime PM autosuspend feature. Typically this is those that relies on parent devices to power the card via runtime PM, like some USB host drivers for example. Signed-off-by: Ulf Hansson Tested-by: Kai-Heng Feng Tested-by: Oleksandr Natalenko

mmc: core: Add ->hs400_prepare_ddr() callback

2018-12-17T07:26:24Z

Some eMMC controllers need specific settings for HS400 mode before the speed mode can be switched to DDR mode, during the HS400 initialization sequence. For that reason, let's introduce a new host callback, ->hs400_prepare_ddr() and invoked it just before switching to DDR mode. Signed-off-by: Yinbo Zhu Signed-off-by: Ulf Hansson

mmc: core: add helper to see if a host is doing a retune

2018-10-08T09:40:43Z

Add a helper to allow host drivers checking if a retune is in progress. Signed-off-by: Niklas Söderlund Reviewed-by: Wolfram Sang Tested-by: Wolfram Sang Signed-off-by: Ulf Hansson

mmc: core: Drop the unused mmc_power_save|restore_host()

2018-07-16T09:21:45Z

The last user of mmc_power_save|restore_host() APIs is gone, hence let's drop them. Drop also the corresponding bus_ops callback, ->power_save|restore() as those becomes redundant. Cc: Tony Lindgren Cc: Eyal Reizer Signed-off-by: Ulf Hansson

mmc: core: more fine-grained hooks for HS400 tuning

2018-07-16T09:21:45Z

This adds two new HS400 tuning operations: * hs400_downgrade * hs400_complete These supplement the existing HS400 operation: * prepare_hs400_tuning This is motivated by a requirement of Renesas SDHI for the following: 1. Disabling SCC before selecting to HS if selection of HS400 has occurred. This can be done in an implementation of prepare_hs400_tuning_downgrade 2. Updating registers after switching to HS400 This can be done in an implementation of complete_hs400_tuning If hs400_downgrade or hs400_complete are not implemented then they are not called. Thus means there should be no affect for existing drivers as none implemt these ops. Signed-off-by: Simon Horman Signed-off-by: Ulf Hansson

mmc: core: add tunable delay waiting for power to be stable

2018-05-21T08:38:50Z

The hard-coded 10ms delay in mmc_power_up came from commit 79bccc5aefb4 ("mmc: increase power up delay"), which said "The TI controller on Toshiba Tecra M5 needs more time to power up or the cards will init incorrectly or not at all." But it's too engineering solution for a special board but force all platforms to wait for that long time, especially painful for mmc_power_up for eMMC when booting. However, it's added since 2009, and we can't tell if other platforms benefit from it. But in practise, the modern hardware are most likely to have a stable power supply with 1ms after setting it for no matter PMIC or discrete power. And more importnatly, most regulators implement the callback of ->set_voltage_time_sel() for regulator core to wait for specific period of time for the power supply to be stable, which means once regulator_set_voltage_* return, the power should reach the the minimum voltage that works for initialization. Of course, if there are some other ways for host to power the card, we should allow them to argue a suitable delay as well. With this patch, we could assign the delay from firmware, or we could assigne it via ->set_ios() callback from host drivers. Signed-off-by: Shawn Lin Signed-off-by: Ulf Hansson