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

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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 <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20200529102341.12529-1-ulf.hansson@linaro.org
This commit is contained in:
Ulf Hansson 2020-05-29 12:23:41 +02:00
parent 11ba468877
commit b52fb259df
3 changed files with 9 additions and 5 deletions
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10
drivers/mmc/core/core.c
View file

@ -1455,12 +1455,12 @@ void mmc_detach_bus(struct mmc_host *host)
void _mmc_detect_change(struct mmc_host *host, unsigned long delay, bool cd_irq)
{
/*
* If the device is configured as wakeup, we prevent a new sleep for
* 5 s to give provision for user space to consume the event.
* Prevent system sleep for 5s to allow user space to consume the
* corresponding uevent. This is especially useful, when CD irq is used
* as a system wakeup, but doesn't hurt in other cases.
*/
if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL) &&
device_can_wakeup(mmc_dev(host)))
pm_wakeup_event(mmc_dev(host), 5000);
if (cd_irq && !(host->caps & MMC_CAP_NEEDS_POLL))
__pm_wakeup_event(host->ws, 5000);
host->detect_change = 1;
mmc_schedule_delayed_work(&host->detect, delay);

3
drivers/mmc/core/host.c
View file

@ -15,6 +15,7 @@
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/pagemap.h>
#include <linux/pm_wakeup.h>
#include <linux/export.h>
#include <linux/leds.h>
#include <linux/slab.h>
@ -36,6 +37,7 @@ static DEFINE_IDA(mmc_host_ida);
static void mmc_host_classdev_release(struct device *dev)
{
struct mmc_host *host = cls_dev_to_mmc_host(dev);
wakeup_source_unregister(host->ws);
ida_simple_remove(&mmc_host_ida, host->index);
kfree(host);
}
@ -400,6 +402,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
host->index = err;
dev_set_name(&host->class_dev, "mmc%d", host->index);
host->ws = wakeup_source_register(NULL, dev_name(&host->class_dev));
host->parent = dev;
host->class_dev.parent = dev;

1
include/linux/mmc/host.h
View file

@ -287,6 +287,7 @@ struct mmc_host {
#ifdef CONFIG_PM_SLEEP
struct notifier_block pm_notify;
#endif
struct wakeup_source *ws; /* Enable consume of uevents */
u32 max_current_330;
u32 max_current_300;
u32 max_current_180;