>From 277ffbe2b37467db52fea9e5b0ebb05cdb26cddf Mon Sep 17 00:00:00 2001 From: Yunpeng Gao <[email protected]> Date: Thu, 16 Dec 2010 19:58:43 +0800 Subject: [PATCH] Do some changes in mmc core layer to enable mmc card runtime pm
Seems current runtime PM support in mmc core layer has some problems: 1. If host controller is PCI device, then it's possibly that the PCI host controller will be runtime suspended immediately after its PCI probe. Then it will have trouble when do the following mmc_rescan since at that time the function driver (mmc block driver or sdio function driver) has not been called and there's no chance to execute pm_runtime_get(). 2. Currently mmc_host_class (defined in drivers/mmc/core/host.c) is parent of mmc_card and child of host controller. But mmc_host_class has not implemented the runtime pm APIs of itself. So seems it'll cause the mmc runtime PM chain disconnect here. This patch tries to fix above 2 problems. For 1, it adds pm_runtime_get/put at the begging/end of function mmc_rescan(). For2, it implements a set of dummy runtime PM API for the mmc_host_class. Signed-off-by: Yunpeng Gao <[email protected]> --- drivers/mmc/core/bus.c | 2 +- drivers/mmc/core/core.c | 4 ++++ drivers/mmc/core/host.c | 36 ++++++++++++++++++++++++++++++++++++ 3 files changed, 41 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/core/bus.c b/drivers/mmc/core/bus.c index af8dc6a..01b8a87 100644 --- a/drivers/mmc/core/bus.c +++ b/drivers/mmc/core/bus.c @@ -160,7 +160,7 @@ static int mmc_runtime_resume(struct device *dev) static int mmc_runtime_idle(struct device *dev) { - return pm_runtime_suspend(dev); + return pm_schedule_suspend(dev, 50); } static const struct dev_pm_ops mmc_bus_pm_ops = { diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index d464252..8a16707 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -22,6 +22,7 @@ #include <linux/scatterlist.h> #include <linux/log2.h> #include <linux/regulator/consumer.h> +#include <linux/pm_runtime.h> #include <linux/mmc/card.h> #include <linux/mmc/host.h> @@ -1449,6 +1450,7 @@ void mmc_rescan(struct work_struct *work) spin_unlock_irqrestore(&host->lock, flags); + pm_runtime_get_sync(host->parent); mmc_bus_get(host); @@ -1544,6 +1546,8 @@ out_fail: mmc_power_off(host); } out: + pm_runtime_put_sync(host->parent); + if (host->caps & MMC_CAP_NEEDS_POLL) mmc_schedule_delayed_work(&host->detect, HZ); } diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 10b8af2..82baa02 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -18,6 +18,7 @@ #include <linux/leds.h> #include <linux/slab.h> #include <linux/suspend.h> +#include <linux/pm_runtime.h> #include <linux/mmc/host.h> @@ -26,6 +27,34 @@ #define cls_dev_to_mmc_host(d) container_of(d, struct mmc_host, class_dev) +#ifdef CONFIG_PM_RUNTIME +static int mmc_host_runtime_suspend(struct device *dev) +{ + return 0; +} + +static int mmc_host_runtime_resume(struct device *dev) +{ + return 0; +} + +static int mmc_host_runtime_idle(struct device *dev) +{ + return pm_runtime_suspend(dev); +} + +#else +#define mmc_host_runtime_suspend NULL +#define mmc_host_runtime_resume NULL +#define mmc_host_runtime_idle NULL +#endif + +static const struct dev_pm_ops host_pm = { + .runtime_suspend = mmc_host_runtime_suspend, + .runtime_resume = mmc_host_runtime_resume, + .runtime_idle = mmc_host_runtime_idle, +}; + static void mmc_host_classdev_release(struct device *dev) { struct mmc_host *host = cls_dev_to_mmc_host(dev); @@ -35,6 +64,7 @@ static void mmc_host_classdev_release(struct device *dev) static struct class mmc_host_class = { .name = "mmc_host", .dev_release = mmc_host_classdev_release, + .pm = &host_pm, }; int mmc_register_host_class(void) @@ -131,6 +161,12 @@ int mmc_add_host(struct mmc_host *host) if (err) return err; + /* enable runtime pm */ + pm_runtime_get_noresume(&host->class_dev); + pm_runtime_set_active(&host->class_dev); + pm_runtime_enable(&host->class_dev); + pm_runtime_put_sync(&host->class_dev); + #ifdef CONFIG_DEBUG_FS mmc_add_host_debugfs(host); #endif -- 1.5.4.5 _______________________________________________ MeeGo-kernel mailing list [email protected] http://lists.meego.com/listinfo/meego-kernel
