---

yaml
---
r: 164706
b: refs/heads/master
c: 8ea926b
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 27cce39f555def6f5ebe7f03d69ccc44ab25f0b2
+refs/heads/master: 8ea926b22e2d13238e4d65d8f61c48fe424e6f4f

trunk/drivers/mmc/core/core.c

@@ -343,6 +343,101 @@ unsigned int mmc_align_data_size(struct mmc_card *card, unsigned int sz)
 }
 EXPORT_SYMBOL(mmc_align_data_size);
 
+/**
+ *	mmc_host_enable - enable a host.
+ *	@host: mmc host to enable
+ *
+ *	Hosts that support power saving can use the 'enable' and 'disable'
+ *	methods to exit and enter power saving states. For more information
+ *	see comments for struct mmc_host_ops.
+ */
+int mmc_host_enable(struct mmc_host *host)
+{
+	if (!(host->caps & MMC_CAP_DISABLE))
+		return 0;
+
+	if (host->en_dis_recurs)
+		return 0;
+
+	if (host->nesting_cnt++)
+		return 0;
+
+	cancel_delayed_work_sync(&host->disable);
+
+	if (host->enabled)
+		return 0;
+
+	if (host->ops->enable) {
+		int err;
+
+		host->en_dis_recurs = 1;
+		err = host->ops->enable(host);
+		host->en_dis_recurs = 0;
+
+		if (err) {
+			pr_debug("%s: enable error %d\n",
+				 mmc_hostname(host), err);
+			return err;
+		}
+	}
+	host->enabled = 1;
+	return 0;
+}
+EXPORT_SYMBOL(mmc_host_enable);
+
+static int mmc_host_do_disable(struct mmc_host *host, int lazy)
+{
+	if (host->ops->disable) {
+		int err;
+
+		host->en_dis_recurs = 1;
+		err = host->ops->disable(host, lazy);
+		host->en_dis_recurs = 0;
+
+		if (err < 0) {
+			pr_debug("%s: disable error %d\n",
+				 mmc_hostname(host), err);
+			return err;
+		}
+		if (err > 0) {
+			unsigned long delay = msecs_to_jiffies(err);
+
+			mmc_schedule_delayed_work(&host->disable, delay);
+		}
+	}
+	host->enabled = 0;
+	return 0;
+}
+
+/**
+ *	mmc_host_disable - disable a host.
+ *	@host: mmc host to disable
+ *
+ *	Hosts that support power saving can use the 'enable' and 'disable'
+ *	methods to exit and enter power saving states. For more information
+ *	see comments for struct mmc_host_ops.
+ */
+int mmc_host_disable(struct mmc_host *host)
+{
+	int err;
+
+	if (!(host->caps & MMC_CAP_DISABLE))
+		return 0;
+
+	if (host->en_dis_recurs)
+		return 0;
+
+	if (--host->nesting_cnt)
+		return 0;
+
+	if (!host->enabled)
+		return 0;
+
+	err = mmc_host_do_disable(host, 0);
+	return err;
+}
+EXPORT_SYMBOL(mmc_host_disable);
+
 /**
  *	__mmc_claim_host - exclusively claim a host
  *	@host: mmc host to claim
@@ -379,11 +474,81 @@ int __mmc_claim_host(struct mmc_host *host, atomic_t *abort)
 		wake_up(&host->wq);
 	spin_unlock_irqrestore(&host->lock, flags);
 	remove_wait_queue(&host->wq, &wait);
+	if (!stop)
+		mmc_host_enable(host);
 	return stop;
 }
 
 EXPORT_SYMBOL(__mmc_claim_host);
 
+static int mmc_try_claim_host(struct mmc_host *host)
+{
+	int claimed_host = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+	if (!host->claimed) {
+		host->claimed = 1;
+		claimed_host = 1;
+	}
+	spin_unlock_irqrestore(&host->lock, flags);
+	return claimed_host;
+}
+
+static void mmc_do_release_host(struct mmc_host *host)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&host->lock, flags);
+	host->claimed = 0;
+	spin_unlock_irqrestore(&host->lock, flags);
+
+	wake_up(&host->wq);
+}
+
+void mmc_host_deeper_disable(struct work_struct *work)
+{
+	struct mmc_host *host =
+		container_of(work, struct mmc_host, disable.work);
+
+	/* If the host is claimed then we do not want to disable it anymore */
+	if (!mmc_try_claim_host(host))
+		return;
+	mmc_host_do_disable(host, 1);
+	mmc_do_release_host(host);
+}
+
+/**
+ *	mmc_host_lazy_disable - lazily disable a host.
+ *	@host: mmc host to disable
+ *
+ *	Hosts that support power saving can use the 'enable' and 'disable'
+ *	methods to exit and enter power saving states. For more information
+ *	see comments for struct mmc_host_ops.
+ */
+int mmc_host_lazy_disable(struct mmc_host *host)
+{
+	if (!(host->caps & MMC_CAP_DISABLE))
+		return 0;
+
+	if (host->en_dis_recurs)
+		return 0;
+
+	if (--host->nesting_cnt)
+		return 0;
+
+	if (!host->enabled)
+		return 0;
+
+	if (host->disable_delay) {
+		mmc_schedule_delayed_work(&host->disable,
+				msecs_to_jiffies(host->disable_delay));
+		return 0;
+	} else
+		return mmc_host_do_disable(host, 1);
+}
+EXPORT_SYMBOL(mmc_host_lazy_disable);
+
 /**
  *	mmc_release_host - release a host
  *	@host: mmc host to release
@@ -393,15 +558,11 @@ EXPORT_SYMBOL(__mmc_claim_host);
  */
 void mmc_release_host(struct mmc_host *host)
 {
-	unsigned long flags;
-
 	WARN_ON(!host->claimed);
 
-	spin_lock_irqsave(&host->lock, flags);
-	host->claimed = 0;
-	spin_unlock_irqrestore(&host->lock, flags);
+	mmc_host_lazy_disable(host);
 
-	wake_up(&host->wq);
+	mmc_do_release_host(host);
 }
 
 EXPORT_SYMBOL(mmc_release_host);
@@ -953,6 +1114,8 @@ void mmc_stop_host(struct mmc_host *host)
 	spin_unlock_irqrestore(&host->lock, flags);
 #endif
 
+	if (host->caps & MMC_CAP_DISABLE)
+		cancel_delayed_work(&host->disable);
 	cancel_delayed_work(&host->detect);
 	mmc_flush_scheduled_work();
 
@@ -981,6 +1144,8 @@ void mmc_stop_host(struct mmc_host *host)
  */
 int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
 {
+	if (host->caps & MMC_CAP_DISABLE)
+		cancel_delayed_work(&host->disable);
 	cancel_delayed_work(&host->detect);
 	mmc_flush_scheduled_work();
 

trunk/drivers/mmc/core/host.c

@@ -83,6 +83,7 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev)
 	spin_lock_init(&host->lock);
 	init_waitqueue_head(&host->wq);
 	INIT_DELAYED_WORK(&host->detect, mmc_rescan);
+	INIT_DELAYED_WORK_DEFERRABLE(&host->disable, mmc_host_deeper_disable);
 
 	/*
 	 * By default, hosts do not support SGIO or large requests.

trunk/drivers/mmc/core/host.h

@@ -14,5 +14,7 @@
 int mmc_register_host_class(void);
 void mmc_unregister_host_class(void);
 
+void mmc_host_deeper_disable(struct work_struct *work);
+
 #endif
 

trunk/include/linux/mmc/host.h

@@ -51,6 +51,35 @@ struct mmc_ios {
 };
 
 struct mmc_host_ops {
+	/*
+	 * Hosts that support power saving can use the 'enable' and 'disable'
+	 * methods to exit and enter power saving states. 'enable' is called
+	 * when the host is claimed and 'disable' is called (or scheduled with
+	 * a delay) when the host is released. The 'disable' is scheduled if
+	 * the disable delay set by 'mmc_set_disable_delay()' is non-zero,
+	 * otherwise 'disable' is called immediately. 'disable' may be
+	 * scheduled repeatedly, to permit ever greater power saving at the
+	 * expense of ever greater latency to re-enable. Rescheduling is
+	 * determined by the return value of the 'disable' method. A positive
+	 * value gives the delay in milliseconds.
+	 *
+	 * In the case where a host function (like set_ios) may be called
+	 * with or without the host claimed, enabling and disabling can be
+	 * done directly and will nest correctly. Call 'mmc_host_enable()' and
+	 * 'mmc_host_lazy_disable()' for this purpose, but note that these
+	 * functions must be paired.
+	 *
+	 * Alternatively, 'mmc_host_enable()' may be paired with
+	 * 'mmc_host_disable()' which calls 'disable' immediately.  In this
+	 * case the 'disable' method will be called with 'lazy' set to 0.
+	 * This is mainly useful for error paths.
+	 *
+	 * Because lazy disable may be called from a work queue, the 'disable'
+	 * method must claim the host when 'lazy' != 0, which will work
+	 * correctly because recursion is detected and handled.
+	 */
+	int (*enable)(struct mmc_host *host);
+	int (*disable)(struct mmc_host *host, int lazy);
 	void	(*request)(struct mmc_host *host, struct mmc_request *req);
 	/*
 	 * Avoid calling these three functions too often or in a "fast path",
@@ -118,6 +147,7 @@ struct mmc_host {
 #define MMC_CAP_SPI		(1 << 4)	/* Talks only SPI protocols */
 #define MMC_CAP_NEEDS_POLL	(1 << 5)	/* Needs polling for card-detection */
 #define MMC_CAP_8_BIT_DATA	(1 << 6)	/* Can the host do 8 bit transfers */
+#define MMC_CAP_DISABLE		(1 << 7)	/* Can the host be disabled */
 
 	/* host specific block data */
 	unsigned int		max_seg_size;	/* see blk_queue_max_segment_size */
@@ -142,6 +172,13 @@ struct mmc_host {
 	unsigned int		removed:1;	/* host is being removed */
 #endif
 
+	/* Only used with MMC_CAP_DISABLE */
+	int			enabled;	/* host is enabled */
+	int			nesting_cnt;	/* "enable" nesting count */
+	int			en_dis_recurs;	/* detect recursion */
+	unsigned int		disable_delay;	/* disable delay in msecs */
+	struct delayed_work	disable;	/* disabling work */
+
 	struct mmc_card		*card;		/* device attached to this host */
 
 	wait_queue_head_t	wq;
@@ -197,5 +234,15 @@ struct regulator;
 int mmc_regulator_get_ocrmask(struct regulator *supply);
 int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
 
+int mmc_host_enable(struct mmc_host *host);
+int mmc_host_disable(struct mmc_host *host);
+int mmc_host_lazy_disable(struct mmc_host *host);
+
+static inline void mmc_set_disable_delay(struct mmc_host *host,
+					 unsigned int disable_delay)
+{
+	host->disable_delay = disable_delay;
+}
+
 #endif