Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6

This file explains the locking and exclusion scheme used in the PCCARD

and PCMCIA subsystems.

A) Overview, Locking Hierarchy:

===============================

pcmcia_socket_list_rwsem	- protects only the list of sockets

- skt_mutex			- serializes card insert / ejection

  - ops_mutex			- serializes socket operation

B) Exclusion

============

The following functions and callbacks to struct pcmcia_socket must

be called with "skt_mutex" held:

	socket_detect_change()

	send_event()

	socket_reset()

	socket_shutdown()

	socket_setup()

	socket_remove()

	socket_insert()

	socket_early_resume()

	socket_late_resume()

	socket_resume()

	socket_suspend()

	struct pcmcia_callback	*callback

The following functions and callbacks to struct pcmcia_socket must

be called with "ops_mutex" held:

	socket_reset()

	socket_setup()

	struct pccard_operations	*ops

	struct pccard_resource_ops	*resource_ops;

Note that send_event() and struct pcmcia_callback *callback must not be

called with "ops_mutex" held.

C) Protection

=============

1. Global Data:

---------------

struct list_head	pcmcia_socket_list;

protected by pcmcia_socket_list_rwsem;

2. Per-Socket Data:

-------------------

The resource_ops and their data are protected by ops_mutex.

The "main" struct pcmcia_socket is protected as follows (read-only fields

or single-use fields not mentioned):

- by pcmcia_socket_list_rwsem:

	struct list_head	socket_list;

- by thread_lock:

	unsigned int		thread_events;

- by skt_mutex:

	u_int			suspended_state;

	void			(*tune_bridge);

	struct pcmcia_callback	*callback;

	int			resume_status;

- by ops_mutex:

	socket_state_t		socket;

	u_int			state;

	u_short			lock_count;

	pccard_mem_map		cis_mem;

	void __iomem 		*cis_virt;

	struct { }		irq;

	io_window_t		io[];

	pccard_mem_map		win[];

	struct list_head	cis_cache;

	size_t			fake_cis_len;

	u8			*fake_cis;

	u_int			irq_mask;

	void 			(*zoom_video);

	int 			(*power_hook);

	u8			resource...;

	struct list_head	devices_list;

	u8			device_count;

	struct 			pcmcia_state;

3. Per PCMCIA-device Data:

--------------------------

The "main" struct pcmcia_devie is protected as follows (read-only fields

or single-use fields not mentioned):

- by pcmcia_socket->ops_mutex:

	struct list_head	socket_device_list;

	struct config_t		*function_config;

	u16			_irq:1;

	u16			_io:1;

	u16			_win:4;

	u16			_locked:1;

	u16			allow_func_id_match:1;

	u16			suspended:1;

	u16			_removed:1;

- by the PCMCIA driver:

	io_req_t		io;

	irq_req_t		irq;

	config_req_t		conf;

	window_handle_t		win;

static ssize_t cmm_write(struct file *filp, const char __user *buf,

			 size_t count, loff_t *ppos)

{

	struct cm4000_dev *dev = (struct cm4000_dev *) filp->private_data;

	struct cm4000_dev *dev = filp->private_data;

	unsigned int iobase = dev->p_dev->io.BasePort1;

	unsigned short s;

	unsigned char tmp;

    link->conf.Attributes |= CONF_ENABLE_SPKR;

    link->conf.Status = CCSR_AUDIO_ENA;

    link->irq.Attributes =

	IRQ_TYPE_DYNAMIC_SHARING;

    link->irq.Attributes = IRQ_TYPE_DYNAMIC_SHARING;

    link->io.IOAddrLines = 16;

    link->io.Attributes2 = IO_DATA_PATH_WIDTH_8;

    link->io.NumPorts2 = 8;

    link->conf.Attributes |= CONF_ENABLE_SPKR;

    link->conf.Status = CCSR_AUDIO_ENA;

    link->irq.Attributes =

	IRQ_TYPE_DYNAMIC_SHARING|IRQ_FIRST_SHARED;

    link->irq.Attributes = IRQ_TYPE_DYNAMIC_SHARING;

    link->io.NumPorts1 = 64;

    link->io.Attributes2 = IO_DATA_PATH_WIDTH_8;

    link->io.NumPorts2 = 8;

	tristate "CardBus yenta-compatible bridge support"

	depends on PCI

	select CARDBUS if !EMBEDDED

	select PCCARD_NONSTATIC

	select PCCARD_NONSTATIC if PCMCIA != n

	---help---

	  This option enables support for CardBus host bridges.  Virtually

	  all modern PCMCIA bridges are CardBus compatible.  A "bridge" is

config PCMCIA_M8XX

	tristate "MPC8xx PCMCIA support"

	depends on PCMCIA && PPC && 8xx

	select PCCARD_IODYN

	select PCCARD_NONSTATIC

	depends on PCCARD && PPC && 8xx

	select PCCARD_IODYN if PCMCIA != n

	help

	  Say Y here to include support for PowerPC 8xx series PCMCIA

	  controller.

config M32R_PCC

	bool "M32R PCMCIA I/F"

	depends on M32R && CHIP_M32700 && PCMCIA

	select PCCARD_NONSTATIC

	help

	  Say Y here to use the M32R PCMCIA controller.

config M32R_CFC

	bool "M32R CF I/F Controller"

	depends on M32R && (PLAT_USRV || PLAT_M32700UT || PLAT_MAPPI2 || PLAT_MAPPI3 || PLAT_OPSPUT)

	select PCCARD_NONSTATIC

	help

	  Say Y here to use the M32R CompactFlash controller.

# Makefile for the kernel pcmcia subsystem (c/o David Hinds)

#

pcmcia_core-y					+= cs.o cistpl.o rsrc_mgr.o socket_sysfs.o

pcmcia_core-y					+= cs.o rsrc_mgr.o socket_sysfs.o

pcmcia_core-$(CONFIG_CARDBUS)			+= cardbus.o

obj-$(CONFIG_PCCARD)				+= pcmcia_core.o

pcmcia-y					+= ds.o pcmcia_resource.o

pcmcia-y					+= ds.o pcmcia_resource.o cistpl.o

pcmcia-$(CONFIG_PCMCIA_IOCTL)			+= pcmcia_ioctl.o

obj-$(CONFIG_PCMCIA)				+= pcmcia.o