1 files changed, 59 insertions, 0 deletions

diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 3e7615e9087e..eaf36364b7d4 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -11,6 +11,7 @@
 #define LINUX_MMC_HOST_H
 
 #include <linux/leds.h>
+#include <linux/sched.h>
 
 #include <linux/mmc/core.h>
 
@@ -51,6 +52,35 @@ 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 +148,9 @@ 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 */
+#define MMC_CAP_NONREMOVABLE    (1 << 8)        /* Nonremovable e.g. eMMC */
+#define MMC_CAP_WAIT_WHILE_BUSY (1 << 9)        /* Waits while card is busy */
 
         /* host specific block data */
         unsigned int            max_seg_size;   /* see blk_queue_max_segment_size */
@@ -142,9 +175,18 @@ 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;
+        struct task_struct      *claimer;       /* task that has host claimed */
+        int                     claim_cnt;      /* "claim" nesting count */
 
         struct delayed_work     detect;
 
@@ -183,6 +225,9 @@ static inline void *mmc_priv(struct mmc_host *host)
 extern int mmc_suspend_host(struct mmc_host *, pm_message_t);
 extern int mmc_resume_host(struct mmc_host *);
 
+extern void mmc_power_save_host(struct mmc_host *host);
+extern void mmc_power_restore_host(struct mmc_host *host);
+
 extern void mmc_detect_change(struct mmc_host *, unsigned long delay);
 extern void mmc_request_done(struct mmc_host *, struct mmc_request *);
 
@@ -197,5 +242,19 @@ struct regulator;
 int mmc_regulator_get_ocrmask(struct regulator *supply);
 int mmc_regulator_set_ocr(struct regulator *supply, unsigned short vdd_bit);
 
+int mmc_card_awake(struct mmc_host *host);
+int mmc_card_sleep(struct mmc_host *host);
+int mmc_card_can_sleep(struct mmc_host *host);
+
+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