kernel/drivers/mmc/core/core.c, 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:fix a bug when max_discard is 0

2019-03-01T08:50:10Z

The original purpose of the code I fix is to replace max_discard with max_trim if max_trim is less than max_discard. When max_discard is 0 we should replace max_discard with max_trim as well, because max_discard equals 0 happens only when the max_do_calc_max_discard process is overflowed, so if mmc_can_trim(card) is true, max_discard should be replaced by an available max_trim. However, in the original code, there are two lines of code interfere the right process. 1) if (max_discard && mmc_can_trim(card)) when max_discard is 0, it skips the process checking if max_discard needs to be replaced with max_trim. 2) if (max_trim < max_discard) the condition is false when max_discard is 0. it also skips the process that replaces max_discard with max_trim, in fact, we should replace the 0-valued max_discard with max_trim. Signed-off-by: Jiong Wu Fixes: b305882fbc87 (mmc: core: optimize mmc_calc_max_discard) Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Ulf Hansson

Merge branch 'fixes' into next

2019-02-28T08:16:18Z

mmc: core: Add sd discard timeout

2019-02-28T08:16:12Z

The busy timeout is 250msec per discard command. Signed-off-by: Avri Altman Signed-off-by: Ulf Hansson

mmc: core: Add discard support to sd

2019-02-28T08:16:12Z

SD spec v5.1 adds discard support. The flows and commands are similar to mmc, so just set the discard arg in CMD38. A host which supports DISCARD shall check if the DISCARD_SUPPORT (b313) is set in the SD_STATUS register. If the card does not support discard, the host shall not issue DISCARD command, but ERASE command instead. Post the DISCARD operation, the card may de-allocate the discarded blocks partially or completely. So the host mustn't make any assumptions concerning the content of the discarded region. This is unlike ERASE command, in which the region is guaranteed to contain either '0's or '1's, depends on the content of DATA_STAT_AFTER_ERASE (b55) in the scr register. One more important difference compared to ERASE is the busy timeout which we will address on the next patch. Signed-off-by: Avri Altman Signed-off-by: Ulf Hansson

mmc: core: Fix NULL ptr crash from mmc_should_fail_request

2019-02-27T09:00:17Z

In case of CQHCI, mrq->cmd may be NULL for data requests (non DCMD). In such case mmc_should_fail_request is directly dereferencing mrq->cmd while cmd is NULL. Fix this by checking for mrq->cmd pointer. Fixes: 72a5af554df8 ("mmc: core: Add support for handling CQE requests") Signed-off-by: Ritesh Harjani Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson

mmc: core: Convert mmc_align_data_size() into an SDIO specific function

2019-02-25T16:20:21Z

The only user of mmc_align_data_size() is sdio_align_size(), which is called from SDIO func drivers to let them distinguish, how to optimally allocate data buffers. Let's move mmc_align_data_size() close to the SDIO code as to make it static, rename it to _sdio_align_size() and simplify its definition, all with the purpose of clarifying that this is SDIO specific. Signed-off-by: Ulf Hansson Reviewed-by: Avri Altman

mmc: core: Move mmc_of_parse_voltage() to host.c

2019-02-25T14:20:58Z

MMC OF parsing functions, which parses various host DT properties, should stay close to each other. Therefore, let's move mmc_of_parse_voltage() close to mmc_of_parse() into host.c. Additionally, there is no reason to build the code only when CONFIG_OF is set, as there should be stub functions for the OF helpers that is being used, so let's drop this condition as well. 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: core: Calculate the discard arg only once

2019-02-25T07:40:58Z

In MMC, the discard arg is a read-only ext_csd parameter - set it once on card init. To be consistent, do that for SD as well even though its discard arg is always 0x0. Signed-off-by: Avri Altman Signed-off-by: Ulf Hansson