kernel.git/drivers/mmc/core/core.c, branch linux-4.1.y

mmc: avoid removing non-removable hosts during suspend

2018-05-23T01:33:51Z

[ Upstream commit de8dcc3d2c0e08e5068ee1e26fc46415c15e3637 ] The Weibu F3C MiniPC has an onboard AP6255 module, presenting two SDIO functions on a single MMC host (Bluetooth/btsdio and WiFi/brcmfmac), and the mmc layer correctly detects this as non-removable. After suspend/resume, the wifi and bluetooth interfaces disappear and do not get probed again. The conditions here are: 1. During suspend, we reach mmc_pm_notify() 2. mmc_pm_notify() calls mmc_sdio_pre_suspend() to see if we can suspend the SDIO host. However, mmc_sdio_pre_suspend() returns -ENOSYS because btsdio_driver does not have a suspend method. 3. mmc_pm_notify() proceeds to remove the card 4. Upon resume, mmc_rescan() does nothing with this host, because of the rescan_entered check which aims to only scan a non-removable device a single time (i.e. during boot). Fix the loss of functionality by detecting that we are unable to suspend a non-removable host, so avoid the forced removal in that case. The comment above this function already indicates that this code was only intended for removable devices. Signed-off-by: Daniel Drake Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin

mmc: longer timeout for long read time quirk

2016-06-06T23:12:33Z

[ Upstream commit 32ecd320db39bcb007679ed42f283740641b81ea ] 008GE0 Toshiba mmc in some Intel Baytrail tablets responds to MMC_SEND_EXT_CSD in 450-600ms. This patch will... () Increase the long read time quirk timeout from 300ms to 600ms. Original author of that quirk says 300ms was only a guess and that the number may need to be raised in the future. () Add this specific MMC to the quirk Signed-off-by: Matt Gumbel Signed-off-by: Adrian Hunter Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson Signed-off-by: Sasha Levin

mmc: core: fix race condition in mmc_wait_data_done

2015-09-29T17:26:13Z

commit 71f8a4b81d040b3d094424197ca2f1bf811b1245 upstream. The following panic is captured in ker3.14, but the issue still exists in latest kernel. --------------------------------------------------------------------- [ 20.738217] c0 3136 (Compiler) Unable to handle kernel NULL pointer dereference at virtual address 00000578 ...... [ 20.738499] c0 3136 (Compiler) PC is at _raw_spin_lock_irqsave+0x24/0x60 [ 20.738527] c0 3136 (Compiler) LR is at _raw_spin_lock_irqsave+0x20/0x60 [ 20.740134] c0 3136 (Compiler) Call trace: [ 20.740165] c0 3136 (Compiler) [] _raw_spin_lock_irqsave+0x24/0x60 [ 20.740200] c0 3136 (Compiler) [] __wake_up+0x1c/0x54 [ 20.740230] c0 3136 (Compiler) [] mmc_wait_data_done+0x28/0x34 [ 20.740262] c0 3136 (Compiler) [] mmc_request_done+0xa4/0x220 [ 20.740314] c0 3136 (Compiler) [] sdhci_tasklet_finish+0xac/0x264 [ 20.740352] c0 3136 (Compiler) [] tasklet_action+0xa0/0x158 [ 20.740382] c0 3136 (Compiler) [] __do_softirq+0x10c/0x2e4 [ 20.740411] c0 3136 (Compiler) [] irq_exit+0x8c/0xc0 [ 20.740439] c0 3136 (Compiler) [] handle_IRQ+0x48/0xac [ 20.740469] c0 3136 (Compiler) [] gic_handle_irq+0x38/0x7c ---------------------------------------------------------------------- Because in SMP, "mrq" has race condition between below two paths: path1: CPU0: static void mmc_wait_data_done(struct mmc_request *mrq) { mrq->host->context_info.is_done_rcv = true; // // If CPU0 has just finished "is_done_rcv = true" in path1, and at // this moment, IRQ or ICache line missing happens in CPU0. // What happens in CPU1 (path2)? // // If the mmcqd thread in CPU1(path2) hasn't entered to sleep mode: // path2 would have chance to break from wait_event_interruptible // in mmc_wait_for_data_req_done and continue to run for next // mmc_request (mmc_blk_rw_rq_prep). // // Within mmc_blk_rq_prep, mrq is cleared to 0. // If below line still gets host from "mrq" as the result of // compiler, the panic happens as we traced. wake_up_interruptible(&mrq->host->context_info.wait); } path2: CPU1: static int mmc_wait_for_data_req_done(... { ... while (1) { wait_event_interruptible(context_info->wait, (context_info->is_done_rcv || context_info->is_new_req)); static void mmc_blk_rw_rq_prep(... { ... memset(brq, 0, sizeof(struct mmc_blk_request)); This issue happens very coincidentally; however adding mdelay(1) in mmc_wait_data_done as below could duplicate it easily. static void mmc_wait_data_done(struct mmc_request *mrq) { mrq->host->context_info.is_done_rcv = true; + mdelay(1); wake_up_interruptible(&mrq->host->context_info.wait); } At runtime, IRQ or ICache line missing may just happen at the same place of the mdelay(1). This patch gets the mmc_context_info at the beginning of function, it can avoid this race condition. Signed-off-by: Jialing Fu Tested-by: Shawn Lin Fixes: 2220eedfd7ae ("mmc: fix async request mechanism ....") Signed-off-by: Shawn Lin Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman

mmc: core: add missing pm event in mmc_pm_notify to fix hib restore

2015-05-04T08:33:33Z

The PM_RESTORE_PREPARE is not handled now in mmc_pm_notify(), as result mmc_rescan() could be scheduled and executed at late hibernation restore stages when MMC device is suspended already - which, in turn, will lead to system crash on TI dra7-evm board: WARNING: CPU: 0 PID: 3188 at drivers/bus/omap_l3_noc.c:148 l3_interrupt_handler+0x258/0x374() 44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER1_P3 (Idle): Data Access in User mode during Functional access Hence, add missed PM_RESTORE_PREPARE PM event in mmc_pm_notify(). Fixes: 4c2ef25fe0b8 (mmc: fix all hangs related to mmc/sd card...) Signed-off-by: Grygorii Strashko Signed-off-by: Ulf Hansson

mmc: core: Enable runtime PM management of host devices

2015-03-31T14:50:14Z

Currently those host drivers which have deployed runtime PM, deals with the runtime PM reference counting entirely by themselves. Since host drivers don't know when the core will send the next request through some of the host_ops callbacks, they need to handle runtime PM get/put between each an every request. In quite many cases this has some negative effects, since it leads to a high frequency of scheduled runtime PM suspend operations. That due to the runtime PM reference count will normally reach zero in-between every request. We can decrease that frequency, by enabling the core to deal with runtime PM reference counting of the host device. Since the core often knows that it will send a seqeunce of requests, it makes sense for it to keep a runtime PM reference count during these periods. More exactly, let's increase the runtime PM reference count by invoking pm_runtime_get_sync() from __mmc_claim_host(). Restore that action by invoking pm_runtime_mark_last_busy() and pm_runtime_put_autosuspend() in mmc_release_host(). In this way a runtime PM reference count will be kept during the complete cycle of a claim -> release host. Signed-off-by: Ulf Hansson Acked-by: Adrian Hunter Acked-by: Konstantin Dorfman

mmc: core: Remove the ->enable|disable() callbacks

2015-03-27T09:57:55Z

These callbacks have been set to deprecated for some time. The last user (omap_hsmmc) has moved away from using them, which thus enables us to completely remove them. Signed-off-by: NeilBrown Signed-off-by: Ulf Hansson

mmc: core: Invoke mmc_pwrseq_post_power_on() prior MMC_POWER_ON state

2015-02-03T19:56:58Z

Host drivers have different ways to sends their "init stream" to the card. Some need to do it as part of a request, some do it from the ->set_ios() callback in the MMC_POWER_ON state and some don't send an "init stream" at all. To be able to use the reset GPIOs from the simple MMC power sequence provider, the card need to be powered and the "init stream" must not have been sent. To cope with these requirements, invoke mmc_pwrseq_post_power_on() prior we change the state to MMC_POWER_ON in mmc_power_up(). Host drivers shall perform power up operations in the MMC_POWER_UP state. Unfortunate three hosts (au1xmmc, cb710-mmc and toshsd) don't conform to this expectation. Instead those ignore the MMC_POWER_UP state and delays their power up operations to the MMC_POWER_ON state. Those hosts needs to change their behavior to enable proper support for the simple MMC power sequence provider. Signed-off-by: Ulf Hansson Reviewed-by: Javier Martinez Canillas Tested-by: Javier Martinez Canillas

mmc: Resolve BKOPS compatability issue

2015-01-29T10:15:12Z

This patch is coming to fix compatibility issue of BKOPS_EN field of EXT_CSD. In eMMC-5.1, BKOPS_EN was changed, and now it has two operational bits: Bit 0 - MANUAL_EN Bit 1 - AUTO_EN In previous eMMC revisions, only Bit 0 was supported. Signed-off-by: Alexey Skidanov Signed-off-by: Ulf Hansson

mmc: core: Initial support for MMC power sequences

2015-01-28T11:31:12Z

System on chip designs may specify a specific MMC power sequence. To successfully detect an (e)MMC/SD/SDIO card, that power sequence must be followed while initializing the card. To be able to handle these SOC specific power sequences, let's add a MMC power sequence interface. It provides the following functions to help the mmc core to deal with these power sequences. mmc_pwrseq_alloc() - Invoked from mmc_of_parse(), to initialize data. mmc_pwrseq_pre_power_on()- Invoked in the beginning of mmc_power_up(). mmc_pwrseq_post_power_on()- Invoked at the end in mmc_power_up(). mmc_pwrseq_power_off()- Invoked from mmc_power_off(). mmc_pwrseq_free() - Invoked from mmc_free_host(), to free data. Each MMC power sequence provider will be responsible to implement a set of callbacks. These callbacks mirrors the functions above. This patch adds the skeleton, following patches will extend the core of the MMC power sequence and add support for a specific simple MMC power sequence. Do note, since the mmc_pwrseq_alloc() is invoked from mmc_of_parse(), host drivers needs to make use of this API to enable the support for MMC power sequences. Moreover the MMC power sequence support depends on CONFIG_OF. Signed-off-by: Ulf Hansson Tested-by: Javier Martinez Canillas Reviewed-by: Javier Martinez Canillas

mmc: core: Move mmc_card_removed() into mmc_start_request()

2015-01-19T08:56:30Z

Both callers of mmc_start_request() call mmc_card_removed() so move that call into mmc_start_request(). This patch is preparation for adding re-tuning support. Signed-off-by: Adrian Hunter Signed-off-by: Ulf Hansson