linux/drivers/spi/spi.c

// SPDX-License-Identifier: GPL-2.0-or-later
// SPI init/core code
//
// Copyright (C) 2005 David Brownell
// Copyright (C) 2008 Secret Lab Technologies Ltd.

#include <linux/acpi.h>
#include <linux/cache.h>
#include <linux/clk/clk-conf.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/export.h>
#include <linux/gpio/consumer.h>
#include <linux/highmem.h>
#include <linux/idr.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/kthread.h>
#include <linux/mod_devicetable.h>
#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/percpu.h>
#include <linux/platform_data/x86/apple.h>
#include <linux/pm_domain.h>
#include <linux/pm_runtime.h>
#include <linux/property.h>
#include <linux/ptp_clock_kernel.h>
#include <linux/sched/rt.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/spi/spi-mem.h>
#include <uapi/linux/sched/types.h>

#define CREATE_TRACE_POINTS
#include <trace/events/spi.h>
EXPORT_TRACEPOINT_SYMBOL();
EXPORT_TRACEPOINT_SYMBOL();

#include "internals.h"

static DEFINE_IDR(spi_master_idr);

static void spidev_release(struct device *dev)
{}

static ssize_t
modalias_show(struct device *dev, struct device_attribute *a, char *buf)
{}
static DEVICE_ATTR_RO(modalias);

static ssize_t driver_override_store(struct device *dev,
				     struct device_attribute *a,
				     const char *buf, size_t count)
{}

static ssize_t driver_override_show(struct device *dev,
				    struct device_attribute *a, char *buf)
{}
static DEVICE_ATTR_RW(driver_override);

static struct spi_statistics __percpu *spi_alloc_pcpu_stats(struct device *dev)
{}

static ssize_t spi_emit_pcpu_stats(struct spi_statistics __percpu *stat,
				   char *buf, size_t offset)
{}

#define SPI_STATISTICS_ATTRS(field, file)

#define SPI_STATISTICS_SHOW_NAME(name, file, field)

#define SPI_STATISTICS_SHOW(field)

SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();

SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();

SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();
SPI_STATISTICS_SHOW();

#define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number)
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();
SPI_STATISTICS_TRANSFER_BYTES_HISTO();

SPI_STATISTICS_SHOW();

static struct attribute *spi_dev_attrs[] =;

static const struct attribute_group spi_dev_group =;

static struct attribute *spi_device_statistics_attrs[] =;

static const struct attribute_group spi_device_statistics_group =;

static const struct attribute_group *spi_dev_groups[] =;

static struct attribute *spi_controller_statistics_attrs[] =;

static const struct attribute_group spi_controller_statistics_group =;

static const struct attribute_group *spi_master_groups[] =;

static void spi_statistics_add_transfer_stats(struct spi_statistics __percpu *pcpu_stats,
					      struct spi_transfer *xfer,
					      struct spi_message *msg)
{}

/*
 * modalias support makes "modprobe $MODALIAS" new-style hotplug work,
 * and the sysfs version makes coldplug work too.
 */
static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, const char *name)
{}

const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev)
{}
EXPORT_SYMBOL_GPL();

const void *spi_get_device_match_data(const struct spi_device *sdev)
{}
EXPORT_SYMBOL_GPL();

static int spi_match_device(struct device *dev, const struct device_driver *drv)
{}

static int spi_uevent(const struct device *dev, struct kobj_uevent_env *env)
{}

static int spi_probe(struct device *dev)
{}

static void spi_remove(struct device *dev)
{}

static void spi_shutdown(struct device *dev)
{}

const struct bus_type spi_bus_type =;
EXPORT_SYMBOL_GPL();

/**
 * __spi_register_driver - register a SPI driver
 * @owner: owner module of the driver to register
 * @sdrv: the driver to register
 * Context: can sleep
 *
 * Return: zero on success, else a negative error code.
 */
int __spi_register_driver(struct module *owner, struct spi_driver *sdrv)
{}
EXPORT_SYMBOL_GPL();

/*-------------------------------------------------------------------------*/

/*
 * SPI devices should normally not be created by SPI device drivers; that
 * would make them board-specific.  Similarly with SPI controller drivers.
 * Device registration normally goes into like arch/.../mach.../board-YYY.c
 * with other readonly (flashable) information about mainboard devices.
 */

struct boardinfo {};

static LIST_HEAD(board_list);
static LIST_HEAD(spi_controller_list);

/*
 * Used to protect add/del operation for board_info list and
 * spi_controller list, and their matching process also used
 * to protect object of type struct idr.
 */
static DEFINE_MUTEX(board_lock);

/**
 * spi_alloc_device - Allocate a new SPI device
 * @ctlr: Controller to which device is connected
 * Context: can sleep
 *
 * Allows a driver to allocate and initialize a spi_device without
 * registering it immediately.  This allows a driver to directly
 * fill the spi_device with device parameters before calling
 * spi_add_device() on it.
 *
 * Caller is responsible to call spi_add_device() on the returned
 * spi_device structure to add it to the SPI controller.  If the caller
 * needs to discard the spi_device without adding it, then it should
 * call spi_dev_put() on it.
 *
 * Return: a pointer to the new device, or NULL.
 */
struct spi_device *spi_alloc_device(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static void spi_dev_set_name(struct spi_device *spi)
{}

/*
 * Zero(0) is a valid physical CS value and can be located at any
 * logical CS in the spi->chip_select[]. If all the physical CS
 * are initialized to 0 then It would be difficult to differentiate
 * between a valid physical CS 0 & an unused logical CS whose physical
 * CS can be 0. As a solution to this issue initialize all the CS to -1.
 * Now all the unused logical CS will have -1 physical CS value & can be
 * ignored while performing physical CS validity checks.
 */
#define SPI_INVALID_CS

static inline bool is_valid_cs(s8 chip_select)
{}

static inline int spi_dev_check_cs(struct device *dev,
				   struct spi_device *spi, u8 idx,
				   struct spi_device *new_spi, u8 new_idx)
{}

static int spi_dev_check(struct device *dev, void *data)
{}

static void spi_cleanup(struct spi_device *spi)
{}

static int __spi_add_device(struct spi_device *spi)
{}

/**
 * spi_add_device - Add spi_device allocated with spi_alloc_device
 * @spi: spi_device to register
 *
 * Companion function to spi_alloc_device.  Devices allocated with
 * spi_alloc_device can be added onto the SPI bus with this function.
 *
 * Return: 0 on success; negative errno on failure
 */
int spi_add_device(struct spi_device *spi)
{}
EXPORT_SYMBOL_GPL();

static void spi_set_all_cs_unused(struct spi_device *spi)
{}

/**
 * spi_new_device - instantiate one new SPI device
 * @ctlr: Controller to which device is connected
 * @chip: Describes the SPI device
 * Context: can sleep
 *
 * On typical mainboards, this is purely internal; and it's not needed
 * after board init creates the hard-wired devices.  Some development
 * platforms may not be able to use spi_register_board_info though, and
 * this is exported so that for example a USB or parport based adapter
 * driver could add devices (which it would learn about out-of-band).
 *
 * Return: the new device, or NULL.
 */
struct spi_device *spi_new_device(struct spi_controller *ctlr,
				  struct spi_board_info *chip)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_unregister_device - unregister a single SPI device
 * @spi: spi_device to unregister
 *
 * Start making the passed SPI device vanish. Normally this would be handled
 * by spi_unregister_controller().
 */
void spi_unregister_device(struct spi_device *spi)
{}
EXPORT_SYMBOL_GPL();

static void spi_match_controller_to_boardinfo(struct spi_controller *ctlr,
					      struct spi_board_info *bi)
{}

/**
 * spi_register_board_info - register SPI devices for a given board
 * @info: array of chip descriptors
 * @n: how many descriptors are provided
 * Context: can sleep
 *
 * Board-specific early init code calls this (probably during arch_initcall)
 * with segments of the SPI device table.  Any device nodes are created later,
 * after the relevant parent SPI controller (bus_num) is defined.  We keep
 * this table of devices forever, so that reloading a controller driver will
 * not make Linux forget about these hard-wired devices.
 *
 * Other code can also call this, e.g. a particular add-on board might provide
 * SPI devices through its expansion connector, so code initializing that board
 * would naturally declare its SPI devices.
 *
 * The board info passed can safely be __initdata ... but be careful of
 * any embedded pointers (platform_data, etc), they're copied as-is.
 *
 * Return: zero on success, else a negative error code.
 */
int spi_register_board_info(struct spi_board_info const *info, unsigned n)
{}

/*-------------------------------------------------------------------------*/

/* Core methods for SPI resource management */

/**
 * spi_res_alloc - allocate a spi resource that is life-cycle managed
 *                 during the processing of a spi_message while using
 *                 spi_transfer_one
 * @spi:     the SPI device for which we allocate memory
 * @release: the release code to execute for this resource
 * @size:    size to alloc and return
 * @gfp:     GFP allocation flags
 *
 * Return: the pointer to the allocated data
 *
 * This may get enhanced in the future to allocate from a memory pool
 * of the @spi_device or @spi_controller to avoid repeated allocations.
 */
static void *spi_res_alloc(struct spi_device *spi, spi_res_release_t release,
			   size_t size, gfp_t gfp)
{}

/**
 * spi_res_free - free an SPI resource
 * @res: pointer to the custom data of a resource
 */
static void spi_res_free(void *res)
{}

/**
 * spi_res_add - add a spi_res to the spi_message
 * @message: the SPI message
 * @res:     the spi_resource
 */
static void spi_res_add(struct spi_message *message, void *res)
{}

/**
 * spi_res_release - release all SPI resources for this message
 * @ctlr:  the @spi_controller
 * @message: the @spi_message
 */
static void spi_res_release(struct spi_controller *ctlr, struct spi_message *message)
{}

/*-------------------------------------------------------------------------*/
#define spi_for_each_valid_cs(spi, idx)

static inline bool spi_is_last_cs(struct spi_device *spi)
{}

static void spi_toggle_csgpiod(struct spi_device *spi, u8 idx, bool enable, bool activate)
{}

static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
{}

#ifdef CONFIG_HAS_DMA
static int spi_map_buf_attrs(struct spi_controller *ctlr, struct device *dev,
			     struct sg_table *sgt, void *buf, size_t len,
			     enum dma_data_direction dir, unsigned long attrs)
{}

int spi_map_buf(struct spi_controller *ctlr, struct device *dev,
		struct sg_table *sgt, void *buf, size_t len,
		enum dma_data_direction dir)
{}

static void spi_unmap_buf_attrs(struct spi_controller *ctlr,
				struct device *dev, struct sg_table *sgt,
				enum dma_data_direction dir,
				unsigned long attrs)
{}

void spi_unmap_buf(struct spi_controller *ctlr, struct device *dev,
		   struct sg_table *sgt, enum dma_data_direction dir)
{}

static int __spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
{}

static int __spi_unmap_msg(struct spi_controller *ctlr, struct spi_message *msg)
{}

static void spi_dma_sync_for_device(struct spi_controller *ctlr,
				    struct spi_transfer *xfer)
{}

static void spi_dma_sync_for_cpu(struct spi_controller *ctlr,
				 struct spi_transfer *xfer)
{}
#else /* !CONFIG_HAS_DMA */
static inline int __spi_map_msg(struct spi_controller *ctlr,
				struct spi_message *msg)
{
	return 0;
}

static inline int __spi_unmap_msg(struct spi_controller *ctlr,
				  struct spi_message *msg)
{
	return 0;
}

static void spi_dma_sync_for_device(struct spi_controller *ctrl,
				    struct spi_transfer *xfer)
{
}

static void spi_dma_sync_for_cpu(struct spi_controller *ctrl,
				 struct spi_transfer *xfer)
{
}
#endif /* !CONFIG_HAS_DMA */

static inline int spi_unmap_msg(struct spi_controller *ctlr,
				struct spi_message *msg)
{}

static int spi_map_msg(struct spi_controller *ctlr, struct spi_message *msg)
{}

static int spi_transfer_wait(struct spi_controller *ctlr,
			     struct spi_message *msg,
			     struct spi_transfer *xfer)
{}

static void _spi_transfer_delay_ns(u32 ns)
{}

int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer)
{}
EXPORT_SYMBOL_GPL();

int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer)
{}
EXPORT_SYMBOL_GPL();

static void _spi_transfer_cs_change_delay(struct spi_message *msg,
					  struct spi_transfer *xfer)
{}

void spi_transfer_cs_change_delay_exec(struct spi_message *msg,
						  struct spi_transfer *xfer)
{}
EXPORT_SYMBOL_GPL();

/*
 * spi_transfer_one_message - Default implementation of transfer_one_message()
 *
 * This is a standard implementation of transfer_one_message() for
 * drivers which implement a transfer_one() operation.  It provides
 * standard handling of delays and chip select management.
 */
static int spi_transfer_one_message(struct spi_controller *ctlr,
				    struct spi_message *msg)
{}

/**
 * spi_finalize_current_transfer - report completion of a transfer
 * @ctlr: the controller reporting completion
 *
 * Called by SPI drivers using the core transfer_one_message()
 * implementation to notify it that the current interrupt driven
 * transfer has finished and the next one may be scheduled.
 */
void spi_finalize_current_transfer(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static void spi_idle_runtime_pm(struct spi_controller *ctlr)
{}

static int __spi_pump_transfer_message(struct spi_controller *ctlr,
		struct spi_message *msg, bool was_busy)
{}

/**
 * __spi_pump_messages - function which processes SPI message queue
 * @ctlr: controller to process queue for
 * @in_kthread: true if we are in the context of the message pump thread
 *
 * This function checks if there is any SPI message in the queue that
 * needs processing and if so call out to the driver to initialize hardware
 * and transfer each message.
 *
 * Note that it is called both from the kthread itself and also from
 * inside spi_sync(); the queue extraction handling at the top of the
 * function should deal with this safely.
 */
static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread)
{}

/**
 * spi_pump_messages - kthread work function which processes spi message queue
 * @work: pointer to kthread work struct contained in the controller struct
 */
static void spi_pump_messages(struct kthread_work *work)
{}

/**
 * spi_take_timestamp_pre - helper to collect the beginning of the TX timestamp
 * @ctlr: Pointer to the spi_controller structure of the driver
 * @xfer: Pointer to the transfer being timestamped
 * @progress: How many words (not bytes) have been transferred so far
 * @irqs_off: If true, will disable IRQs and preemption for the duration of the
 *	      transfer, for less jitter in time measurement. Only compatible
 *	      with PIO drivers. If true, must follow up with
 *	      spi_take_timestamp_post or otherwise system will crash.
 *	      WARNING: for fully predictable results, the CPU frequency must
 *	      also be under control (governor).
 *
 * This is a helper for drivers to collect the beginning of the TX timestamp
 * for the requested byte from the SPI transfer. The frequency with which this
 * function must be called (once per word, once for the whole transfer, once
 * per batch of words etc) is arbitrary as long as the @tx buffer offset is
 * greater than or equal to the requested byte at the time of the call. The
 * timestamp is only taken once, at the first such call. It is assumed that
 * the driver advances its @tx buffer pointer monotonically.
 */
void spi_take_timestamp_pre(struct spi_controller *ctlr,
			    struct spi_transfer *xfer,
			    size_t progress, bool irqs_off)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_take_timestamp_post - helper to collect the end of the TX timestamp
 * @ctlr: Pointer to the spi_controller structure of the driver
 * @xfer: Pointer to the transfer being timestamped
 * @progress: How many words (not bytes) have been transferred so far
 * @irqs_off: If true, will re-enable IRQs and preemption for the local CPU.
 *
 * This is a helper for drivers to collect the end of the TX timestamp for
 * the requested byte from the SPI transfer. Can be called with an arbitrary
 * frequency: only the first call where @tx exceeds or is equal to the
 * requested word will be timestamped.
 */
void spi_take_timestamp_post(struct spi_controller *ctlr,
			     struct spi_transfer *xfer,
			     size_t progress, bool irqs_off)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_set_thread_rt - set the controller to pump at realtime priority
 * @ctlr: controller to boost priority of
 *
 * This can be called because the controller requested realtime priority
 * (by setting the ->rt value before calling spi_register_controller()) or
 * because a device on the bus said that its transfers needed realtime
 * priority.
 *
 * NOTE: at the moment if any device on a bus says it needs realtime then
 * the thread will be at realtime priority for all transfers on that
 * controller.  If this eventually becomes a problem we may see if we can
 * find a way to boost the priority only temporarily during relevant
 * transfers.
 */
static void spi_set_thread_rt(struct spi_controller *ctlr)
{}

static int spi_init_queue(struct spi_controller *ctlr)
{}

/**
 * spi_get_next_queued_message() - called by driver to check for queued
 * messages
 * @ctlr: the controller to check for queued messages
 *
 * If there are more messages in the queue, the next message is returned from
 * this call.
 *
 * Return: the next message in the queue, else NULL if the queue is empty.
 */
struct spi_message *spi_get_next_queued_message(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

/*
 * __spi_unoptimize_message - shared implementation of spi_unoptimize_message()
 *                            and spi_maybe_unoptimize_message()
 * @msg: the message to unoptimize
 *
 * Peripheral drivers should use spi_unoptimize_message() and callers inside
 * core should use spi_maybe_unoptimize_message() rather than calling this
 * function directly.
 *
 * It is not valid to call this on a message that is not currently optimized.
 */
static void __spi_unoptimize_message(struct spi_message *msg)
{}

/*
 * spi_maybe_unoptimize_message - unoptimize msg not managed by a peripheral
 * @msg: the message to unoptimize
 *
 * This function is used to unoptimize a message if and only if it was
 * optimized by the core (via spi_maybe_optimize_message()).
 */
static void spi_maybe_unoptimize_message(struct spi_message *msg)
{}

/**
 * spi_finalize_current_message() - the current message is complete
 * @ctlr: the controller to return the message to
 *
 * Called by the driver to notify the core that the message in the front of the
 * queue is complete and can be removed from the queue.
 */
void spi_finalize_current_message(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static int spi_start_queue(struct spi_controller *ctlr)
{}

static int spi_stop_queue(struct spi_controller *ctlr)
{}

static int spi_destroy_queue(struct spi_controller *ctlr)
{}

static int __spi_queued_transfer(struct spi_device *spi,
				 struct spi_message *msg,
				 bool need_pump)
{}

/**
 * spi_queued_transfer - transfer function for queued transfers
 * @spi: SPI device which is requesting transfer
 * @msg: SPI message which is to handled is queued to driver queue
 *
 * Return: zero on success, else a negative error code.
 */
static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg)
{}

static int spi_controller_initialize_queue(struct spi_controller *ctlr)
{}

/**
 * spi_flush_queue - Send all pending messages in the queue from the callers'
 *		     context
 * @ctlr: controller to process queue for
 *
 * This should be used when one wants to ensure all pending messages have been
 * sent before doing something. Is used by the spi-mem code to make sure SPI
 * memory operations do not preempt regular SPI transfers that have been queued
 * before the spi-mem operation.
 */
void spi_flush_queue(struct spi_controller *ctlr)
{}

/*-------------------------------------------------------------------------*/

#if defined(CONFIG_OF)
static void of_spi_parse_dt_cs_delay(struct device_node *nc,
				     struct spi_delay *delay, const char *prop)
{}

static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
			   struct device_node *nc)
{}

static struct spi_device *
of_register_spi_device(struct spi_controller *ctlr, struct device_node *nc)
{}

/**
 * of_register_spi_devices() - Register child devices onto the SPI bus
 * @ctlr:	Pointer to spi_controller device
 *
 * Registers an spi_device for each child node of controller node which
 * represents a valid SPI slave.
 */
static void of_register_spi_devices(struct spi_controller *ctlr)
{}
#else
static void of_register_spi_devices(struct spi_controller *ctlr) { }
#endif

/**
 * spi_new_ancillary_device() - Register ancillary SPI device
 * @spi:         Pointer to the main SPI device registering the ancillary device
 * @chip_select: Chip Select of the ancillary device
 *
 * Register an ancillary SPI device; for example some chips have a chip-select
 * for normal device usage and another one for setup/firmware upload.
 *
 * This may only be called from main SPI device's probe routine.
 *
 * Return: 0 on success; negative errno on failure
 */
struct spi_device *spi_new_ancillary_device(struct spi_device *spi,
					     u8 chip_select)
{}
EXPORT_SYMBOL_GPL();

#ifdef CONFIG_ACPI
struct acpi_spi_lookup {};

static int acpi_spi_count(struct acpi_resource *ares, void *data)
{}

/**
 * acpi_spi_count_resources - Count the number of SpiSerialBus resources
 * @adev:	ACPI device
 *
 * Return: the number of SpiSerialBus resources in the ACPI-device's
 * resource-list; or a negative error code.
 */
int acpi_spi_count_resources(struct acpi_device *adev)
{}
EXPORT_SYMBOL_GPL();

static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
					    struct acpi_spi_lookup *lookup)
{}

static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
{}

/**
 * acpi_spi_device_alloc - Allocate a spi device, and fill it in with ACPI information
 * @ctlr: controller to which the spi device belongs
 * @adev: ACPI Device for the spi device
 * @index: Index of the spi resource inside the ACPI Node
 *
 * This should be used to allocate a new SPI device from and ACPI Device node.
 * The caller is responsible for calling spi_add_device to register the SPI device.
 *
 * If ctlr is set to NULL, the Controller for the SPI device will be looked up
 * using the resource.
 * If index is set to -1, index is not used.
 * Note: If index is -1, ctlr must be set.
 *
 * Return: a pointer to the new device, or ERR_PTR on error.
 */
struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr,
					 struct acpi_device *adev,
					 int index)
{}
EXPORT_SYMBOL_GPL();

static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
					    struct acpi_device *adev)
{}

static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level,
				       void *data, void **return_value)
{}

#define SPI_ACPI_ENUMERATE_MAX_DEPTH

static void acpi_register_spi_devices(struct spi_controller *ctlr)
{}
#else
static inline void acpi_register_spi_devices(struct spi_controller *ctlr) {}
#endif /* CONFIG_ACPI */

static void spi_controller_release(struct device *dev)
{}

static struct class spi_master_class =;

#ifdef CONFIG_SPI_SLAVE
/**
 * spi_slave_abort - abort the ongoing transfer request on an SPI slave
 *		     controller
 * @spi: device used for the current transfer
 */
int spi_slave_abort(struct spi_device *spi)
{}
EXPORT_SYMBOL_GPL();

int spi_target_abort(struct spi_device *spi)
{}
EXPORT_SYMBOL_GPL();

static ssize_t slave_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{}

static ssize_t slave_store(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count)
{}

static DEVICE_ATTR_RW(slave);

static struct attribute *spi_slave_attrs[] =;

static const struct attribute_group spi_slave_group =;

static const struct attribute_group *spi_slave_groups[] =;

static struct class spi_slave_class =;
#else
extern struct class spi_slave_class;	/* dummy */
#endif

/**
 * __spi_alloc_controller - allocate an SPI master or slave controller
 * @dev: the controller, possibly using the platform_bus
 * @size: how much zeroed driver-private data to allocate; the pointer to this
 *	memory is in the driver_data field of the returned device, accessible
 *	with spi_controller_get_devdata(); the memory is cacheline aligned;
 *	drivers granting DMA access to portions of their private data need to
 *	round up @size using ALIGN(size, dma_get_cache_alignment()).
 * @slave: flag indicating whether to allocate an SPI master (false) or SPI
 *	slave (true) controller
 * Context: can sleep
 *
 * This call is used only by SPI controller drivers, which are the
 * only ones directly touching chip registers.  It's how they allocate
 * an spi_controller structure, prior to calling spi_register_controller().
 *
 * This must be called from context that can sleep.
 *
 * The caller is responsible for assigning the bus number and initializing the
 * controller's methods before calling spi_register_controller(); and (after
 * errors adding the device) calling spi_controller_put() to prevent a memory
 * leak.
 *
 * Return: the SPI controller structure on success, else NULL.
 */
struct spi_controller *__spi_alloc_controller(struct device *dev,
					      unsigned int size, bool slave)
{}
EXPORT_SYMBOL_GPL();

static void devm_spi_release_controller(struct device *dev, void *ctlr)
{}

/**
 * __devm_spi_alloc_controller - resource-managed __spi_alloc_controller()
 * @dev: physical device of SPI controller
 * @size: how much zeroed driver-private data to allocate
 * @slave: whether to allocate an SPI master (false) or SPI slave (true)
 * Context: can sleep
 *
 * Allocate an SPI controller and automatically release a reference on it
 * when @dev is unbound from its driver.  Drivers are thus relieved from
 * having to call spi_controller_put().
 *
 * The arguments to this function are identical to __spi_alloc_controller().
 *
 * Return: the SPI controller structure on success, else NULL.
 */
struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
						   unsigned int size,
						   bool slave)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_get_gpio_descs() - grab chip select GPIOs for the master
 * @ctlr: The SPI master to grab GPIO descriptors for
 */
static int spi_get_gpio_descs(struct spi_controller *ctlr)
{}

static int spi_controller_check_ops(struct spi_controller *ctlr)
{}

/* Allocate dynamic bus number using Linux idr */
static int spi_controller_id_alloc(struct spi_controller *ctlr, int start, int end)
{}

/**
 * spi_register_controller - register SPI master or slave controller
 * @ctlr: initialized master, originally from spi_alloc_master() or
 *	spi_alloc_slave()
 * Context: can sleep
 *
 * SPI controllers connect to their drivers using some non-SPI bus,
 * such as the platform bus.  The final stage of probe() in that code
 * includes calling spi_register_controller() to hook up to this SPI bus glue.
 *
 * SPI controllers use board specific (often SOC specific) bus numbers,
 * and board-specific addressing for SPI devices combines those numbers
 * with chip select numbers.  Since SPI does not directly support dynamic
 * device identification, boards need configuration tables telling which
 * chip is at which address.
 *
 * This must be called from context that can sleep.  It returns zero on
 * success, else a negative error code (dropping the controller's refcount).
 * After a successful return, the caller is responsible for calling
 * spi_unregister_controller().
 *
 * Return: zero on success, else a negative error code.
 */
int spi_register_controller(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static void devm_spi_unregister(struct device *dev, void *res)
{}

/**
 * devm_spi_register_controller - register managed SPI master or slave
 *	controller
 * @dev:    device managing SPI controller
 * @ctlr: initialized controller, originally from spi_alloc_master() or
 *	spi_alloc_slave()
 * Context: can sleep
 *
 * Register a SPI device as with spi_register_controller() which will
 * automatically be unregistered and freed.
 *
 * Return: zero on success, else a negative error code.
 */
int devm_spi_register_controller(struct device *dev,
				 struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static int __unregister(struct device *dev, void *null)
{}

/**
 * spi_unregister_controller - unregister SPI master or slave controller
 * @ctlr: the controller being unregistered
 * Context: can sleep
 *
 * This call is used only by SPI controller drivers, which are the
 * only ones directly touching chip registers.
 *
 * This must be called from context that can sleep.
 *
 * Note that this function also drops a reference to the controller.
 */
void spi_unregister_controller(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

static inline int __spi_check_suspended(const struct spi_controller *ctlr)
{}

static inline void __spi_mark_suspended(struct spi_controller *ctlr)
{}

static inline void __spi_mark_resumed(struct spi_controller *ctlr)
{}

int spi_controller_suspend(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

int spi_controller_resume(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

/*-------------------------------------------------------------------------*/

/* Core methods for spi_message alterations */

static void __spi_replace_transfers_release(struct spi_controller *ctlr,
					    struct spi_message *msg,
					    void *res)
{}

/**
 * spi_replace_transfers - replace transfers with several transfers
 *                         and register change with spi_message.resources
 * @msg:           the spi_message we work upon
 * @xfer_first:    the first spi_transfer we want to replace
 * @remove:        number of transfers to remove
 * @insert:        the number of transfers we want to insert instead
 * @release:       extra release code necessary in some circumstances
 * @extradatasize: extra data to allocate (with alignment guarantees
 *                 of struct @spi_transfer)
 * @gfp:           gfp flags
 *
 * Returns: pointer to @spi_replaced_transfers,
 *          PTR_ERR(...) in case of errors.
 */
static struct spi_replaced_transfers *spi_replace_transfers(
	struct spi_message *msg,
	struct spi_transfer *xfer_first,
	size_t remove,
	size_t insert,
	spi_replaced_release_t release,
	size_t extradatasize,
	gfp_t gfp)
{}

static int __spi_split_transfer_maxsize(struct spi_controller *ctlr,
					struct spi_message *msg,
					struct spi_transfer **xferp,
					size_t maxsize)
{}

/**
 * spi_split_transfers_maxsize - split spi transfers into multiple transfers
 *                               when an individual transfer exceeds a
 *                               certain size
 * @ctlr:    the @spi_controller for this transfer
 * @msg:   the @spi_message to transform
 * @maxsize:  the maximum when to apply this
 *
 * This function allocates resources that are automatically freed during the
 * spi message unoptimize phase so this function should only be called from
 * optimize_message callbacks.
 *
 * Return: status of transformation
 */
int spi_split_transfers_maxsize(struct spi_controller *ctlr,
				struct spi_message *msg,
				size_t maxsize)
{}
EXPORT_SYMBOL_GPL();


/**
 * spi_split_transfers_maxwords - split SPI transfers into multiple transfers
 *                                when an individual transfer exceeds a
 *                                certain number of SPI words
 * @ctlr:     the @spi_controller for this transfer
 * @msg:      the @spi_message to transform
 * @maxwords: the number of words to limit each transfer to
 *
 * This function allocates resources that are automatically freed during the
 * spi message unoptimize phase so this function should only be called from
 * optimize_message callbacks.
 *
 * Return: status of transformation
 */
int spi_split_transfers_maxwords(struct spi_controller *ctlr,
				 struct spi_message *msg,
				 size_t maxwords)
{}
EXPORT_SYMBOL_GPL();

/*-------------------------------------------------------------------------*/

/*
 * Core methods for SPI controller protocol drivers. Some of the
 * other core methods are currently defined as inline functions.
 */

static int __spi_validate_bits_per_word(struct spi_controller *ctlr,
					u8 bits_per_word)
{}

/**
 * spi_set_cs_timing - configure CS setup, hold, and inactive delays
 * @spi: the device that requires specific CS timing configuration
 *
 * Return: zero on success, else a negative error code.
 */
static int spi_set_cs_timing(struct spi_device *spi)
{}

/**
 * spi_setup - setup SPI mode and clock rate
 * @spi: the device whose settings are being modified
 * Context: can sleep, and no requests are queued to the device
 *
 * SPI protocol drivers may need to update the transfer mode if the
 * device doesn't work with its default.  They may likewise need
 * to update clock rates or word sizes from initial values.  This function
 * changes those settings, and must be called from a context that can sleep.
 * Except for SPI_CS_HIGH, which takes effect immediately, the changes take
 * effect the next time the device is selected and data is transferred to
 * or from it.  When this function returns, the SPI device is deselected.
 *
 * Note that this call will fail if the protocol driver specifies an option
 * that the underlying controller or its driver does not support.  For
 * example, not all hardware supports wire transfers using nine bit words,
 * LSB-first wire encoding, or active-high chipselects.
 *
 * Return: zero on success, else a negative error code.
 */
int spi_setup(struct spi_device *spi)
{}
EXPORT_SYMBOL_GPL();

static int _spi_xfer_word_delay_update(struct spi_transfer *xfer,
				       struct spi_device *spi)
{}

static int __spi_validate(struct spi_device *spi, struct spi_message *message)
{}

/*
 * spi_split_transfers - generic handling of transfer splitting
 * @msg: the message to split
 *
 * Under certain conditions, a SPI controller may not support arbitrary
 * transfer sizes or other features required by a peripheral. This function
 * will split the transfers in the message into smaller transfers that are
 * supported by the controller.
 *
 * Controllers with special requirements not covered here can also split
 * transfers in the optimize_message() callback.
 *
 * Context: can sleep
 * Return: zero on success, else a negative error code
 */
static int spi_split_transfers(struct spi_message *msg)
{}

/*
 * __spi_optimize_message - shared implementation for spi_optimize_message()
 *                          and spi_maybe_optimize_message()
 * @spi: the device that will be used for the message
 * @msg: the message to optimize
 *
 * Peripheral drivers will call spi_optimize_message() and the spi core will
 * call spi_maybe_optimize_message() instead of calling this directly.
 *
 * It is not valid to call this on a message that has already been optimized.
 *
 * Return: zero on success, else a negative error code
 */
static int __spi_optimize_message(struct spi_device *spi,
				  struct spi_message *msg)
{}

/*
 * spi_maybe_optimize_message - optimize message if it isn't already pre-optimized
 * @spi: the device that will be used for the message
 * @msg: the message to optimize
 * Return: zero on success, else a negative error code
 */
static int spi_maybe_optimize_message(struct spi_device *spi,
				      struct spi_message *msg)
{}

/**
 * spi_optimize_message - do any one-time validation and setup for a SPI message
 * @spi: the device that will be used for the message
 * @msg: the message to optimize
 *
 * Peripheral drivers that reuse the same message repeatedly may call this to
 * perform as much message prep as possible once, rather than repeating it each
 * time a message transfer is performed to improve throughput and reduce CPU
 * usage.
 *
 * Once a message has been optimized, it cannot be modified with the exception
 * of updating the contents of any xfer->tx_buf (the pointer can't be changed,
 * only the data in the memory it points to).
 *
 * Calls to this function must be balanced with calls to spi_unoptimize_message()
 * to avoid leaking resources.
 *
 * Context: can sleep
 * Return: zero on success, else a negative error code
 */
int spi_optimize_message(struct spi_device *spi, struct spi_message *msg)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_unoptimize_message - releases any resources allocated by spi_optimize_message()
 * @msg: the message to unoptimize
 *
 * Calls to this function must be balanced with calls to spi_optimize_message().
 *
 * Context: can sleep
 */
void spi_unoptimize_message(struct spi_message *msg)
{}
EXPORT_SYMBOL_GPL();

static int __spi_async(struct spi_device *spi, struct spi_message *message)
{}

static void devm_spi_unoptimize_message(void *msg)
{}

/**
 * devm_spi_optimize_message - managed version of spi_optimize_message()
 * @dev: the device that manages @msg (usually @spi->dev)
 * @spi: the device that will be used for the message
 * @msg: the message to optimize
 * Return: zero on success, else a negative error code
 *
 * spi_unoptimize_message() will automatically be called when the device is
 * removed.
 */
int devm_spi_optimize_message(struct device *dev, struct spi_device *spi,
			      struct spi_message *msg)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_async - asynchronous SPI transfer
 * @spi: device with which data will be exchanged
 * @message: describes the data transfers, including completion callback
 * Context: any (IRQs may be blocked, etc)
 *
 * This call may be used in_irq and other contexts which can't sleep,
 * as well as from task contexts which can sleep.
 *
 * The completion callback is invoked in a context which can't sleep.
 * Before that invocation, the value of message->status is undefined.
 * When the callback is issued, message->status holds either zero (to
 * indicate complete success) or a negative error code.  After that
 * callback returns, the driver which issued the transfer request may
 * deallocate the associated memory; it's no longer in use by any SPI
 * core or controller driver code.
 *
 * Note that although all messages to a spi_device are handled in
 * FIFO order, messages may go to different devices in other orders.
 * Some device might be higher priority, or have various "hard" access
 * time requirements, for example.
 *
 * On detection of any fault during the transfer, processing of
 * the entire message is aborted, and the device is deselected.
 * Until returning from the associated message completion callback,
 * no other spi_message queued to that device will be processed.
 * (This rule applies equally to all the synchronous transfer calls,
 * which are wrappers around this core asynchronous primitive.)
 *
 * Return: zero on success, else a negative error code.
 */
int spi_async(struct spi_device *spi, struct spi_message *message)
{}
EXPORT_SYMBOL_GPL();

static void __spi_transfer_message_noqueue(struct spi_controller *ctlr, struct spi_message *msg)
{}

/*-------------------------------------------------------------------------*/

/*
 * Utility methods for SPI protocol drivers, layered on
 * top of the core.  Some other utility methods are defined as
 * inline functions.
 */

static void spi_complete(void *arg)
{}

static int __spi_sync(struct spi_device *spi, struct spi_message *message)
{}

/**
 * spi_sync - blocking/synchronous SPI data transfers
 * @spi: device with which data will be exchanged
 * @message: describes the data transfers
 * Context: can sleep
 *
 * This call may only be used from a context that may sleep.  The sleep
 * is non-interruptible, and has no timeout.  Low-overhead controller
 * drivers may DMA directly into and out of the message buffers.
 *
 * Note that the SPI device's chip select is active during the message,
 * and then is normally disabled between messages.  Drivers for some
 * frequently-used devices may want to minimize costs of selecting a chip,
 * by leaving it selected in anticipation that the next message will go
 * to the same chip.  (That may increase power usage.)
 *
 * Also, the caller is guaranteeing that the memory associated with the
 * message will not be freed before this call returns.
 *
 * Return: zero on success, else a negative error code.
 */
int spi_sync(struct spi_device *spi, struct spi_message *message)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_sync_locked - version of spi_sync with exclusive bus usage
 * @spi: device with which data will be exchanged
 * @message: describes the data transfers
 * Context: can sleep
 *
 * This call may only be used from a context that may sleep.  The sleep
 * is non-interruptible, and has no timeout.  Low-overhead controller
 * drivers may DMA directly into and out of the message buffers.
 *
 * This call should be used by drivers that require exclusive access to the
 * SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus must
 * be released by a spi_bus_unlock call when the exclusive access is over.
 *
 * Return: zero on success, else a negative error code.
 */
int spi_sync_locked(struct spi_device *spi, struct spi_message *message)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_bus_lock - obtain a lock for exclusive SPI bus usage
 * @ctlr: SPI bus master that should be locked for exclusive bus access
 * Context: can sleep
 *
 * This call may only be used from a context that may sleep.  The sleep
 * is non-interruptible, and has no timeout.
 *
 * This call should be used by drivers that require exclusive access to the
 * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the
 * exclusive access is over. Data transfer must be done by spi_sync_locked
 * and spi_async_locked calls when the SPI bus lock is held.
 *
 * Return: always zero.
 */
int spi_bus_lock(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

/**
 * spi_bus_unlock - release the lock for exclusive SPI bus usage
 * @ctlr: SPI bus master that was locked for exclusive bus access
 * Context: can sleep
 *
 * This call may only be used from a context that may sleep.  The sleep
 * is non-interruptible, and has no timeout.
 *
 * This call releases an SPI bus lock previously obtained by an spi_bus_lock
 * call.
 *
 * Return: always zero.
 */
int spi_bus_unlock(struct spi_controller *ctlr)
{}
EXPORT_SYMBOL_GPL();

/* Portable code must never pass more than 32 bytes */
#define SPI_BUFSIZ

static u8	*buf;

/**
 * spi_write_then_read - SPI synchronous write followed by read
 * @spi: device with which data will be exchanged
 * @txbuf: data to be written (need not be DMA-safe)
 * @n_tx: size of txbuf, in bytes
 * @rxbuf: buffer into which data will be read (need not be DMA-safe)
 * @n_rx: size of rxbuf, in bytes
 * Context: can sleep
 *
 * This performs a half duplex MicroWire style transaction with the
 * device, sending txbuf and then reading rxbuf.  The return value
 * is zero for success, else a negative errno status code.
 * This call may only be used from a context that may sleep.
 *
 * Parameters to this routine are always copied using a small buffer.
 * Performance-sensitive or bulk transfer code should instead use
 * spi_{async,sync}() calls with DMA-safe buffers.
 *
 * Return: zero on success, else a negative error code.
 */
int spi_write_then_read(struct spi_device *spi,
		const void *txbuf, unsigned n_tx,
		void *rxbuf, unsigned n_rx)
{}
EXPORT_SYMBOL_GPL();

/*-------------------------------------------------------------------------*/

#if IS_ENABLED(CONFIG_OF_DYNAMIC)
/* Must call put_device() when done with returned spi_device device */
static struct spi_device *of_find_spi_device_by_node(struct device_node *node)
{}

/* The spi controllers are not using spi_bus, so we find it with another way */
static struct spi_controller *of_find_spi_controller_by_node(struct device_node *node)
{}

static int of_spi_notify(struct notifier_block *nb, unsigned long action,
			 void *arg)
{}

static struct notifier_block spi_of_notifier =;
#else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
extern struct notifier_block spi_of_notifier;
#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */

#if IS_ENABLED(CONFIG_ACPI)
static int spi_acpi_controller_match(struct device *dev, const void *data)
{}

struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev)
{}
EXPORT_SYMBOL_GPL();

static struct spi_device *acpi_spi_find_device_by_adev(struct acpi_device *adev)
{}

static int acpi_spi_notify(struct notifier_block *nb, unsigned long value,
			   void *arg)
{}

static struct notifier_block spi_acpi_notifier =;
#else
extern struct notifier_block spi_acpi_notifier;
#endif

static int __init spi_init(void)
{}

/*
 * A board_info is normally registered in arch_initcall(),
 * but even essential drivers wait till later.
 *
 * REVISIT only boardinfo really needs static linking. The rest (device and
 * driver registration) _could_ be dynamically linked (modular) ... Costs
 * include needing to have boardinfo data structures be much more public.
 */
postcore_initcall(spi_init);