alistair23-linux/include/linux/mmc/host.h
Nicolas Pitre da68c4eb25 sdio: introduce API for special power management features
This patch series provides the core changes needed to allow SDIO cards to
remain powered and active while the host system is suspended, and let them
wake up the host system when needed.  This is used to implement
wake-on-lan with SDIO wireless cards at the moment.  Patches to add that
support to the libertas driver will be posted separately.

This patch:

Some SDIO cards have the ability to keep on running autonomously when the
host system is suspended, and wake it up when needed.  This however
requires that the host controller preserve power to the card, and
configure itself appropriately for wake-up.

There is however 4 layers of abstractions involved: the host controller
driver, the MMC core code, the SDIO card management code, and the actual
SDIO function driver.  To make things simple and manageable, host drivers
must advertise their PM capabilities with a feature bitmask, then function
drivers can query and set those features from their suspend method.  Then
each layer in the suspend call chain is expected to act upon those bits
accordingly.

[akpm@linux-foundation.org: fix typo in comment]
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-03-06 11:26:36 -08:00

266 lines
9.1 KiB
C

/*
* linux/include/linux/mmc/host.h
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Host driver specific definitions.
*/
#ifndef LINUX_MMC_HOST_H
#define LINUX_MMC_HOST_H
#include <linux/leds.h>
#include <linux/sched.h>
#include <linux/mmc/core.h>
#include <linux/mmc/pm.h>
struct mmc_ios {
unsigned int clock; /* clock rate */
unsigned short vdd;
/* vdd stores the bit number of the selected voltage range from below. */
unsigned char bus_mode; /* command output mode */
#define MMC_BUSMODE_OPENDRAIN 1
#define MMC_BUSMODE_PUSHPULL 2
unsigned char chip_select; /* SPI chip select */
#define MMC_CS_DONTCARE 0
#define MMC_CS_HIGH 1
#define MMC_CS_LOW 2
unsigned char power_mode; /* power supply mode */
#define MMC_POWER_OFF 0
#define MMC_POWER_UP 1
#define MMC_POWER_ON 2
unsigned char bus_width; /* data bus width */
#define MMC_BUS_WIDTH_1 0
#define MMC_BUS_WIDTH_4 2
#define MMC_BUS_WIDTH_8 3
unsigned char timing; /* timing specification used */
#define MMC_TIMING_LEGACY 0
#define MMC_TIMING_MMC_HS 1
#define MMC_TIMING_SD_HS 2
};
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",
* since underlaying controller might implement them in an expensive
* and/or slow way.
*
* Also note that these functions might sleep, so don't call them
* in the atomic contexts!
*
* Return values for the get_ro callback should be:
* 0 for a read/write card
* 1 for a read-only card
* -ENOSYS when not supported (equal to NULL callback)
* or a negative errno value when something bad happened
*
* Return values for the get_cd callback should be:
* 0 for a absent card
* 1 for a present card
* -ENOSYS when not supported (equal to NULL callback)
* or a negative errno value when something bad happened
*/
void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios);
int (*get_ro)(struct mmc_host *host);
int (*get_cd)(struct mmc_host *host);
void (*enable_sdio_irq)(struct mmc_host *host, int enable);
};
struct mmc_card;
struct device;
struct mmc_host {
struct device *parent;
struct device class_dev;
int index;
const struct mmc_host_ops *ops;
unsigned int f_min;
unsigned int f_max;
u32 ocr_avail;
#define MMC_VDD_165_195 0x00000080 /* VDD voltage 1.65 - 1.95 */
#define MMC_VDD_20_21 0x00000100 /* VDD voltage 2.0 ~ 2.1 */
#define MMC_VDD_21_22 0x00000200 /* VDD voltage 2.1 ~ 2.2 */
#define MMC_VDD_22_23 0x00000400 /* VDD voltage 2.2 ~ 2.3 */
#define MMC_VDD_23_24 0x00000800 /* VDD voltage 2.3 ~ 2.4 */
#define MMC_VDD_24_25 0x00001000 /* VDD voltage 2.4 ~ 2.5 */
#define MMC_VDD_25_26 0x00002000 /* VDD voltage 2.5 ~ 2.6 */
#define MMC_VDD_26_27 0x00004000 /* VDD voltage 2.6 ~ 2.7 */
#define MMC_VDD_27_28 0x00008000 /* VDD voltage 2.7 ~ 2.8 */
#define MMC_VDD_28_29 0x00010000 /* VDD voltage 2.8 ~ 2.9 */
#define MMC_VDD_29_30 0x00020000 /* VDD voltage 2.9 ~ 3.0 */
#define MMC_VDD_30_31 0x00040000 /* VDD voltage 3.0 ~ 3.1 */
#define MMC_VDD_31_32 0x00080000 /* VDD voltage 3.1 ~ 3.2 */
#define MMC_VDD_32_33 0x00100000 /* VDD voltage 3.2 ~ 3.3 */
#define MMC_VDD_33_34 0x00200000 /* VDD voltage 3.3 ~ 3.4 */
#define MMC_VDD_34_35 0x00400000 /* VDD voltage 3.4 ~ 3.5 */
#define MMC_VDD_35_36 0x00800000 /* VDD voltage 3.5 ~ 3.6 */
unsigned long caps; /* Host capabilities */
#define MMC_CAP_4_BIT_DATA (1 << 0) /* Can the host do 4 bit transfers */
#define MMC_CAP_MMC_HIGHSPEED (1 << 1) /* Can do MMC high-speed timing */
#define MMC_CAP_SD_HIGHSPEED (1 << 2) /* Can do SD high-speed timing */
#define MMC_CAP_SDIO_IRQ (1 << 3) /* Can signal pending SDIO IRQs */
#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 */
mmc_pm_flag_t pm_caps; /* supported pm features */
/* host specific block data */
unsigned int max_seg_size; /* see blk_queue_max_segment_size */
unsigned short max_hw_segs; /* see blk_queue_max_hw_segments */
unsigned short max_phys_segs; /* see blk_queue_max_phys_segments */
unsigned short unused;
unsigned int max_req_size; /* maximum number of bytes in one req */
unsigned int max_blk_size; /* maximum size of one mmc block */
unsigned int max_blk_count; /* maximum number of blocks in one req */
/* private data */
spinlock_t lock; /* lock for claim and bus ops */
struct mmc_ios ios; /* current io bus settings */
u32 ocr; /* the current OCR setting */
/* group bitfields together to minimize padding */
unsigned int use_spi_crc:1;
unsigned int claimed:1; /* host exclusively claimed */
unsigned int bus_dead:1; /* bus has been released */
#ifdef CONFIG_MMC_DEBUG
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;
const struct mmc_bus_ops *bus_ops; /* current bus driver */
unsigned int bus_refs; /* reference counter */
unsigned int sdio_irqs;
struct task_struct *sdio_irq_thread;
atomic_t sdio_irq_thread_abort;
mmc_pm_flag_t pm_flags; /* requested pm features */
#ifdef CONFIG_LEDS_TRIGGERS
struct led_trigger *led; /* activity led */
#endif
struct dentry *debugfs_root;
unsigned long private[0] ____cacheline_aligned;
};
extern struct mmc_host *mmc_alloc_host(int extra, struct device *);
extern int mmc_add_host(struct mmc_host *);
extern void mmc_remove_host(struct mmc_host *);
extern void mmc_free_host(struct mmc_host *);
static inline void *mmc_priv(struct mmc_host *host)
{
return (void *)host->private;
}
#define mmc_host_is_spi(host) ((host)->caps & MMC_CAP_SPI)
#define mmc_dev(x) ((x)->parent)
#define mmc_classdev(x) (&(x)->class_dev)
#define mmc_hostname(x) (dev_name(&(x)->class_dev))
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 *);
static inline void mmc_signal_sdio_irq(struct mmc_host *host)
{
host->ops->enable_sdio_irq(host, 0);
wake_up_process(host->sdio_irq_thread);
}
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