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authorYacine Belkadi2012-02-24 11:56:55 +0100
committerYacine Belkadi2012-06-11 13:39:46 +0200
commit4a4feb5ea154b56d1eeba7394db12a98b048721c (patch)
treeaeadb041220b7046f4e8b1cab14011229d79309b /polux/linux-2.6.10
parent1aa095f75ab91155fb5d62e78cb7658f426526a7 (diff)
polux/linux: import the SPI framework from Linux 2.6.25, refs #2964
Copies from master at 31afe8813e218ba2bee76b3f1e653266e7f6f670
Diffstat (limited to 'polux/linux-2.6.10')
-rw-r--r--polux/linux-2.6.10/arch/arm/Kconfig2
-rw-r--r--polux/linux-2.6.10/drivers/Kconfig2
-rw-r--r--polux/linux-2.6.10/drivers/Makefile1
-rw-r--r--polux/linux-2.6.10/drivers/spi/Kconfig256
-rw-r--r--polux/linux-2.6.10/drivers/spi/Makefile44
-rw-r--r--polux/linux-2.6.10/drivers/spi/spi.c677
-rw-r--r--polux/linux-2.6.10/include/linux/spi/flash.h31
-rw-r--r--polux/linux-2.6.10/include/linux/spi/spi.h792
8 files changed, 1805 insertions, 0 deletions
diff --git a/polux/linux-2.6.10/arch/arm/Kconfig b/polux/linux-2.6.10/arch/arm/Kconfig
index b2c5f930f6..468d9e8e92 100644
--- a/polux/linux-2.6.10/arch/arm/Kconfig
+++ b/polux/linux-2.6.10/arch/arm/Kconfig
@@ -910,6 +910,8 @@ source "drivers/char/Kconfig"
source "drivers/i2c/Kconfig"
+source "drivers/spi/Kconfig"
+
#source "drivers/l3/Kconfig"
#source "drivers/media/Kconfig"
diff --git a/polux/linux-2.6.10/drivers/Kconfig b/polux/linux-2.6.10/drivers/Kconfig
index 0cf52eb4e8..79c01e0fb3 100644
--- a/polux/linux-2.6.10/drivers/Kconfig
+++ b/polux/linux-2.6.10/drivers/Kconfig
@@ -42,6 +42,8 @@ source "drivers/char/Kconfig"
source "drivers/i2c/Kconfig"
+source "drivers/spi/Kconfig"
+
source "drivers/w1/Kconfig"
source "drivers/misc/Kconfig"
diff --git a/polux/linux-2.6.10/drivers/Makefile b/polux/linux-2.6.10/drivers/Makefile
index b398aa8bd9..b2048f7918 100644
--- a/polux/linux-2.6.10/drivers/Makefile
+++ b/polux/linux-2.6.10/drivers/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_FUSION) += message/
obj-$(CONFIG_IEEE1394) += ieee1394/
#obj-y += cdrom/
obj-$(CONFIG_MTD) += mtd/
+obj-$(CONFIG_SPI) += spi/
obj-$(CONFIG_PCCARD) += pcmcia/
obj-$(CONFIG_DIO) += dio/
obj-$(CONFIG_SBUS) += sbus/
diff --git a/polux/linux-2.6.10/drivers/spi/Kconfig b/polux/linux-2.6.10/drivers/spi/Kconfig
new file mode 100644
index 0000000000..498c6cef03
--- /dev/null
+++ b/polux/linux-2.6.10/drivers/spi/Kconfig
@@ -0,0 +1,256 @@
+#
+# SPI driver configuration
+#
+# NOTE: the reason this doesn't show SPI slave support is mostly that
+# nobody's needed a slave side API yet. The master-role API is not
+# fully appropriate there, so it'd need some thought to do well.
+#
+menu "SPI support"
+ depends on HAS_IOMEM
+
+config SPI
+ bool "SPI support"
+ help
+ The "Serial Peripheral Interface" is a low level synchronous
+ protocol. Chips that support SPI can have data transfer rates
+ up to several tens of Mbit/sec. Chips are addressed with a
+ controller and a chipselect. Most SPI slaves don't support
+ dynamic device discovery; some are even write-only or read-only.
+
+ SPI is widely used by microcontrollers to talk with sensors,
+ eeprom and flash memory, codecs and various other controller
+ chips, analog to digital (and d-to-a) converters, and more.
+ MMC and SD cards can be accessed using SPI protocol; and for
+ DataFlash cards used in MMC sockets, SPI must always be used.
+
+ SPI is one of a family of similar protocols using a four wire
+ interface (select, clock, data in, data out) including Microwire
+ (half duplex), SSP, SSI, and PSP. This driver framework should
+ work with most such devices and controllers.
+
+config SPI_DEBUG
+ boolean "Debug support for SPI drivers"
+ depends on SPI && DEBUG_KERNEL
+ help
+ Say "yes" to enable debug messaging (like dev_dbg and pr_debug),
+ sysfs, and debugfs support in SPI controller and protocol drivers.
+
+#
+# MASTER side ... talking to discrete SPI slave chips including microcontrollers
+#
+
+config SPI_MASTER
+# boolean "SPI Master Support"
+ boolean
+ default SPI
+ help
+ If your system has an master-capable SPI controller (which
+ provides the clock and chipselect), you can enable that
+ controller and the protocol drivers for the SPI slave chips
+ that are connected.
+
+comment "SPI Master Controller Drivers"
+ depends on SPI_MASTER
+
+config SPI_ATMEL
+ tristate "Atmel SPI Controller"
+ depends on (ARCH_AT91 || AVR32) && SPI_MASTER
+ help
+ This selects a driver for the Atmel SPI Controller, present on
+ many AT32 (AVR32) and AT91 (ARM) chips.
+
+config SPI_SPC300
+ tristate "SPiDCOM SPI Controller"
+ depends on (ARCH_SPC300) && SPI_MASTER
+ help
+ This selects a driver for the SPiDCOM SPI Controller, present on
+ SPC300 (ARM) chips.
+
+config SPI_BFIN
+ tristate "SPI controller driver for ADI Blackfin5xx"
+ depends on SPI_MASTER && BLACKFIN
+ help
+ This is the SPI controller master driver for Blackfin 5xx processor.
+
+config SPI_AU1550
+ tristate "Au1550/Au12x0 SPI Controller"
+ depends on SPI_MASTER && (SOC_AU1550 || SOC_AU1200) && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ If you say yes to this option, support will be included for the
+ Au1550 SPI controller (may also work with Au1200,Au1210,Au1250).
+
+ This driver can also be built as a module. If so, the module
+ will be called au1550_spi.
+
+config SPI_BITBANG
+ tristate "Bitbanging SPI master"
+ depends on SPI_MASTER && EXPERIMENTAL
+ help
+ With a few GPIO pins, your system can bitbang the SPI protocol.
+ Select this to get SPI support through I/O pins (GPIO, parallel
+ port, etc). Or, some systems' SPI master controller drivers use
+ this code to manage the per-word or per-transfer accesses to the
+ hardware shift registers.
+
+ This is library code, and is automatically selected by drivers that
+ need it. You only need to select this explicitly to support driver
+ modules that aren't part of this kernel tree.
+
+config SPI_BUTTERFLY
+ tristate "Parallel port adapter for AVR Butterfly (DEVELOPMENT)"
+ depends on SPI_MASTER && PARPORT && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ This uses a custom parallel port cable to connect to an AVR
+ Butterfly <http://www.atmel.com/products/avr/butterfly>, an
+ inexpensive battery powered microcontroller evaluation board.
+ This same cable can be used to flash new firmware.
+
+config SPI_IMX
+ tristate "Freescale iMX SPI controller"
+ depends on SPI_MASTER && ARCH_IMX && EXPERIMENTAL
+ help
+ This enables using the Freescale iMX SPI controller in master
+ mode.
+
+config SPI_LM70_LLP
+ tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)"
+ depends on SPI_MASTER && PARPORT && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ This driver supports the NS LM70 LLP Evaluation Board,
+ which interfaces to an LM70 temperature sensor using
+ a parallel port.
+
+config SPI_MPC52xx_PSC
+ tristate "Freescale MPC52xx PSC SPI controller"
+ depends on SPI_MASTER && PPC_MPC52xx && EXPERIMENTAL
+ help
+ This enables using the Freescale MPC52xx Programmable Serial
+ Controller in master SPI mode.
+
+config SPI_MPC83xx
+ tristate "Freescale MPC83xx/QUICC Engine SPI controller"
+ depends on SPI_MASTER && (PPC_83xx || QUICC_ENGINE) && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ This enables using the Freescale MPC83xx and QUICC Engine SPI
+ controllers in master mode.
+
+ Note, this driver uniquely supports the SPI controller on the MPC83xx
+ family of PowerPC processors, plus processors with QUICC Engine
+ technology. This driver uses a simple set of shift registers for data
+ (opposed to the CPM based descriptor model).
+
+config SPI_OMAP_UWIRE
+ tristate "OMAP1 MicroWire"
+ depends on SPI_MASTER && ARCH_OMAP1
+ select SPI_BITBANG
+ help
+ This hooks up to the MicroWire controller on OMAP1 chips.
+
+config SPI_OMAP24XX
+ tristate "McSPI driver for OMAP24xx/OMAP34xx"
+ depends on SPI_MASTER && (ARCH_OMAP24XX || ARCH_OMAP34XX)
+ help
+ SPI master controller for OMAP24xx/OMAP34xx Multichannel SPI
+ (McSPI) modules.
+
+config SPI_PXA2XX
+ tristate "PXA2xx SSP SPI master"
+ depends on SPI_MASTER && ARCH_PXA && EXPERIMENTAL
+ select PXA_SSP
+ help
+ This enables using a PXA2xx SSP port as a SPI master controller.
+ The driver can be configured to use any SSP port and additional
+ documentation can be found a Documentation/spi/pxa2xx.
+
+config SPI_S3C24XX
+ tristate "Samsung S3C24XX series SPI"
+ depends on SPI_MASTER && ARCH_S3C2410 && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ SPI driver for Samsung S3C24XX series ARM SoCs
+
+config SPI_S3C24XX_GPIO
+ tristate "Samsung S3C24XX series SPI by GPIO"
+ depends on SPI_MASTER && ARCH_S3C2410 && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ SPI driver for Samsung S3C24XX series ARM SoCs using
+ GPIO lines to provide the SPI bus. This can be used where
+ the inbuilt hardware cannot provide the transfer mode, or
+ where the board is using non hardware connected pins.
+
+config SPI_SH_SCI
+ tristate "SuperH SCI SPI controller"
+ depends on SPI_MASTER && SUPERH
+ select SPI_BITBANG
+ help
+ SPI driver for SuperH SCI blocks.
+
+config SPI_TXX9
+ tristate "Toshiba TXx9 SPI controller"
+ depends on SPI_MASTER && GENERIC_GPIO && CPU_TX49XX
+ help
+ SPI driver for Toshiba TXx9 MIPS SoCs
+
+config SPI_XILINX
+ tristate "Xilinx SPI controller"
+ depends on SPI_MASTER && XILINX_VIRTEX && EXPERIMENTAL
+ select SPI_BITBANG
+ help
+ This exposes the SPI controller IP from the Xilinx EDK.
+
+ See the "OPB Serial Peripheral Interface (SPI) (v1.00e)"
+ Product Specification document (DS464) for hardware details.
+
+#
+# Add new SPI master controllers in alphabetical order above this line
+#
+
+#
+# There are lots of SPI device types, with sensors and memory
+# being probably the most widely used ones.
+#
+comment "SPI Protocol Masters"
+ depends on SPI_MASTER
+
+config SPI_AT25
+ tristate "SPI EEPROMs from most vendors"
+ depends on SPI_MASTER && SYSFS
+ help
+ Enable this driver to get read/write support to most SPI EEPROMs,
+ after you configure the board init code to know about each eeprom
+ on your target board.
+
+ This driver can also be built as a module. If so, the module
+ will be called at25.
+
+config SPI_SPIDEV
+ tristate "User mode SPI device driver support"
+ depends on SPI_MASTER && EXPERIMENTAL
+ help
+ This supports user mode SPI protocol drivers.
+
+ Note that this application programming interface is EXPERIMENTAL
+ and hence SUBJECT TO CHANGE WITHOUT NOTICE while it stabilizes.
+
+config SPI_TLE62X0
+ tristate "Infineon TLE62X0 (for power switching)"
+ depends on SPI_MASTER && SYSFS
+ help
+ SPI driver for Infineon TLE62X0 series line driver chips,
+ such as the TLE6220, TLE6230 and TLE6240. This provides a
+ sysfs interface, with each line presented as a kind of GPIO
+ exposing both switch control and diagnostic feedback.
+
+#
+# Add new SPI protocol masters in alphabetical order above this line
+#
+
+# (slave support would go here)
+
+endmenu # "SPI support"
+
diff --git a/polux/linux-2.6.10/drivers/spi/Makefile b/polux/linux-2.6.10/drivers/spi/Makefile
new file mode 100644
index 0000000000..1b15600c1a
--- /dev/null
+++ b/polux/linux-2.6.10/drivers/spi/Makefile
@@ -0,0 +1,44 @@
+#
+# Makefile for kernel SPI drivers.
+#
+
+ifeq ($(CONFIG_SPI_DEBUG),y)
+EXTRA_CFLAGS += -DDEBUG
+endif
+
+# small core, mostly translating board-specific
+# config declarations into driver model code
+obj-$(CONFIG_SPI_MASTER) += spi.o
+
+# SPI master controller drivers (bus)
+obj-$(CONFIG_SPI_ATMEL) += atmel_spi.o
+obj-$(CONFIG_SPI_BFIN) += spi_bfin5xx.o
+obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o
+obj-$(CONFIG_SPI_AU1550) += au1550_spi.o
+obj-$(CONFIG_SPI_BUTTERFLY) += spi_butterfly.o
+obj-$(CONFIG_SPI_IMX) += spi_imx.o
+obj-$(CONFIG_SPI_LM70_LLP) += spi_lm70llp.o
+obj-$(CONFIG_SPI_PXA2XX) += pxa2xx_spi.o
+obj-$(CONFIG_SPI_OMAP_UWIRE) += omap_uwire.o
+obj-$(CONFIG_SPI_OMAP24XX) += omap2_mcspi.o
+obj-$(CONFIG_SPI_MPC52xx_PSC) += mpc52xx_psc_spi.o
+obj-$(CONFIG_SPI_MPC83xx) += spi_mpc83xx.o
+obj-$(CONFIG_SPI_S3C24XX_GPIO) += spi_s3c24xx_gpio.o
+obj-$(CONFIG_SPI_S3C24XX) += spi_s3c24xx.o
+obj-$(CONFIG_SPI_TXX9) += spi_txx9.o
+obj-$(CONFIG_SPI_XILINX) += xilinx_spi.o
+obj-$(CONFIG_SPI_SH_SCI) += spi_sh_sci.o
+obj-$(CONFIG_SPI_SPC300) += spc300_spi.o
+# ... add above this line ...
+
+# SPI protocol drivers (device/link on bus)
+obj-$(CONFIG_SPI_AT25) += at25.o
+obj-$(CONFIG_SPI_SPIDEV) += spidev.o
+obj-$(CONFIG_SPI_TLE62X0) += tle62x0.o
+# ... add above this line ...
+
+# SPI slave controller drivers (upstream link)
+# ... add above this line ...
+
+# SPI slave drivers (protocol for that link)
+# ... add above this line ...
diff --git a/polux/linux-2.6.10/drivers/spi/spi.c b/polux/linux-2.6.10/drivers/spi/spi.c
new file mode 100644
index 0000000000..1ad12afc6b
--- /dev/null
+++ b/polux/linux-2.6.10/drivers/spi/spi.c
@@ -0,0 +1,677 @@
+/*
+ * spi.c - SPI init/core code
+ *
+ * Copyright (C) 2005 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/cache.h>
+#include <linux/mutex.h>
+#include <linux/spi/spi.h>
+
+
+/* SPI bustype and spi_master class are registered after board init code
+ * provides the SPI device tables, ensuring that both are present by the
+ * time controller driver registration causes spi_devices to "enumerate".
+ */
+static void spidev_release(struct device *dev)
+{
+ struct spi_device *spi = to_spi_device(dev);
+
+ /* spi masters may cleanup for released devices */
+ if (spi->master->cleanup)
+ spi->master->cleanup(spi);
+
+ spi_master_put(spi->master);
+ kfree(dev);
+}
+
+static ssize_t
+modalias_show(struct device *dev, struct device_attribute *a, char *buf)
+{
+ const struct spi_device *spi = to_spi_device(dev);
+
+ return snprintf(buf, BUS_ID_SIZE + 1, "%s\n", spi->modalias);
+}
+
+static struct device_attribute spi_dev_attrs[] = {
+ __ATTR_RO(modalias),
+ __ATTR_NULL,
+};
+
+/* modalias support makes "modprobe $MODALIAS" new-style hotplug work,
+ * and the sysfs version makes coldplug work too.
+ */
+
+static int spi_match_device(struct device *dev, struct device_driver *drv)
+{
+ const struct spi_device *spi = to_spi_device(dev);
+
+ return strncmp(spi->modalias, drv->name, BUS_ID_SIZE) == 0;
+}
+
+static int spi_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ const struct spi_device *spi = to_spi_device(dev);
+
+ add_uevent_var(env, "MODALIAS=%s", spi->modalias);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int spi_suspend(struct device *dev, pm_message_t message)
+{
+ int value = 0;
+ struct spi_driver *drv = to_spi_driver(dev->driver);
+
+ /* suspend will stop irqs and dma; no more i/o */
+ if (drv) {
+ if (drv->suspend)
+ value = drv->suspend(to_spi_device(dev), message);
+ else
+ dev_dbg(dev, "... can't suspend\n");
+ }
+ return value;
+}
+
+static int spi_resume(struct device *dev)
+{
+ int value = 0;
+ struct spi_driver *drv = to_spi_driver(dev->driver);
+
+ /* resume may restart the i/o queue */
+ if (drv) {
+ if (drv->resume)
+ value = drv->resume(to_spi_device(dev));
+ else
+ dev_dbg(dev, "... can't resume\n");
+ }
+ return value;
+}
+
+#else
+#define spi_suspend NULL
+#define spi_resume NULL
+#endif
+
+struct bus_type spi_bus_type = {
+ .name = "spi",
+ .dev_attrs = spi_dev_attrs,
+ .match = spi_match_device,
+ .uevent = spi_uevent,
+ .suspend = spi_suspend,
+ .resume = spi_resume,
+};
+EXPORT_SYMBOL_GPL(spi_bus_type);
+
+
+static int spi_drv_probe(struct device *dev)
+{
+ const struct spi_driver *sdrv = to_spi_driver(dev->driver);
+
+ return sdrv->probe(to_spi_device(dev));
+}
+
+static int spi_drv_remove(struct device *dev)
+{
+ const struct spi_driver *sdrv = to_spi_driver(dev->driver);
+
+ return sdrv->remove(to_spi_device(dev));
+}
+
+static void spi_drv_shutdown(struct device *dev)
+{
+ const struct spi_driver *sdrv = to_spi_driver(dev->driver);
+
+ sdrv->shutdown(to_spi_device(dev));
+}
+
+/**
+ * spi_register_driver - register a SPI driver
+ * @sdrv: the driver to register
+ * Context: can sleep
+ */
+int spi_register_driver(struct spi_driver *sdrv)
+{
+ sdrv->driver.bus = &spi_bus_type;
+ if (sdrv->probe)
+ sdrv->driver.probe = spi_drv_probe;
+ if (sdrv->remove)
+ sdrv->driver.remove = spi_drv_remove;
+ if (sdrv->shutdown)
+ sdrv->driver.shutdown = spi_drv_shutdown;
+ return driver_register(&sdrv->driver);
+}
+EXPORT_SYMBOL_GPL(spi_register_driver);
+
+/*-------------------------------------------------------------------------*/
+
+/* SPI devices should normally not be created by SPI device drivers; that
+ * would make them board-specific. Similarly with SPI master drivers.
+ * Device registration normally goes into like arch/.../mach.../board-YYY.c
+ * with other readonly (flashable) information about mainboard devices.
+ */
+
+struct boardinfo {
+ struct list_head list;
+ unsigned n_board_info;
+ struct spi_board_info board_info[0];
+};
+
+static LIST_HEAD(board_list);
+static DEFINE_MUTEX(board_lock);
+
+
+/**
+ * spi_new_device - instantiate one new SPI device
+ * @master: 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).
+ *
+ * Returns the new device, or NULL.
+ */
+struct spi_device *spi_new_device(struct spi_master *master,
+ struct spi_board_info *chip)
+{
+ struct spi_device *proxy;
+ struct device *dev = master->dev.parent;
+ int status;
+
+ /* NOTE: caller did any chip->bus_num checks necessary.
+ *
+ * Also, unless we change the return value convention to use
+ * error-or-pointer (not NULL-or-pointer), troubleshootability
+ * suggests syslogged diagnostics are best here (ugh).
+ */
+
+ /* Chipselects are numbered 0..max; validate. */
+ if (chip->chip_select >= master->num_chipselect) {
+ dev_err(dev, "cs%d > max %d\n",
+ chip->chip_select,
+ master->num_chipselect);
+ return NULL;
+ }
+
+ if (!spi_master_get(master))
+ return NULL;
+
+ proxy = kzalloc(sizeof *proxy, GFP_KERNEL);
+ if (!proxy) {
+ dev_err(dev, "can't alloc dev for cs%d\n",
+ chip->chip_select);
+ goto fail;
+ }
+ proxy->master = master;
+ proxy->chip_select = chip->chip_select;
+ proxy->max_speed_hz = chip->max_speed_hz;
+ proxy->mode = chip->mode;
+ proxy->irq = chip->irq;
+ proxy->modalias = chip->modalias;
+
+ snprintf(proxy->dev.bus_id, sizeof proxy->dev.bus_id,
+ "%s.%u", master->dev.bus_id,
+ chip->chip_select);
+ proxy->dev.parent = dev;
+ proxy->dev.bus = &spi_bus_type;
+ proxy->dev.platform_data = (void *) chip->platform_data;
+ proxy->controller_data = chip->controller_data;
+ proxy->controller_state = NULL;
+ proxy->dev.release = spidev_release;
+
+ /* drivers may modify this initial i/o setup */
+ status = master->setup(proxy);
+ if (status < 0) {
+ dev_err(dev, "can't %s %s, status %d\n",
+ "setup", proxy->dev.bus_id, status);
+ goto fail;
+ }
+
+ /* driver core catches callers that misbehave by defining
+ * devices that already exist.
+ */
+ status = device_register(&proxy->dev);
+ if (status < 0) {
+ dev_err(dev, "can't %s %s, status %d\n",
+ "add", proxy->dev.bus_id, status);
+ goto fail;
+ }
+ dev_dbg(dev, "registered child %s\n", proxy->dev.bus_id);
+ return proxy;
+
+fail:
+ spi_master_put(master);
+ kfree(proxy);
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(spi_new_device);
+
+/**
+ * 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.
+ */
+int __init
+spi_register_board_info(struct spi_board_info const *info, unsigned n)
+{
+ struct boardinfo *bi;
+
+ bi = kmalloc(sizeof(*bi) + n * sizeof *info, GFP_KERNEL);
+ if (!bi)
+ return -ENOMEM;
+ bi->n_board_info = n;
+ memcpy(bi->board_info, info, n * sizeof *info);
+
+ mutex_lock(&board_lock);
+ list_add_tail(&bi->list, &board_list);
+ mutex_unlock(&board_lock);
+ return 0;
+}
+
+/* FIXME someone should add support for a __setup("spi", ...) that
+ * creates board info from kernel command lines
+ */
+
+static void scan_boardinfo(struct spi_master *master)
+{
+ struct boardinfo *bi;
+
+ mutex_lock(&board_lock);
+ list_for_each_entry(bi, &board_list, list) {
+ struct spi_board_info *chip = bi->board_info;
+ unsigned n;
+
+ for (n = bi->n_board_info; n > 0; n--, chip++) {
+ if (chip->bus_num != master->bus_num)
+ continue;
+ /* NOTE: this relies on spi_new_device to
+ * issue diagnostics when given bogus inputs
+ */
+ (void) spi_new_device(master, chip);
+ }
+ }
+ mutex_unlock(&board_lock);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static void spi_master_release(struct device *dev)
+{
+ struct spi_master *master;
+
+ master = container_of(dev, struct spi_master, dev);
+ kfree(master);
+}
+
+static struct class spi_master_class = {
+ .name = "spi_master",
+ .owner = THIS_MODULE,
+ .dev_release = spi_master_release,
+};
+
+
+/**
+ * spi_alloc_master - allocate SPI master 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_master_get_devdata().
+ * Context: can sleep
+ *
+ * This call is used only by SPI master controller drivers, which are the
+ * only ones directly touching chip registers. It's how they allocate
+ * an spi_master structure, prior to calling spi_register_master().
+ *
+ * This must be called from context that can sleep. It returns the SPI
+ * master structure on success, else NULL.
+ *
+ * The caller is responsible for assigning the bus number and initializing
+ * the master's methods before calling spi_register_master(); and (after errors
+ * adding the device) calling spi_master_put() to prevent a memory leak.
+ */
+struct spi_master *spi_alloc_master(struct device *dev, unsigned size)
+{
+ struct spi_master *master;
+
+ if (!dev)
+ return NULL;
+
+ master = kzalloc(size + sizeof *master, GFP_KERNEL);
+ if (!master)
+ return NULL;
+
+ device_initialize(&master->dev);
+ master->dev.class = &spi_master_class;
+ master->dev.parent = get_device(dev);
+ spi_master_set_devdata(master, &master[1]);
+
+ return master;
+}
+EXPORT_SYMBOL_GPL(spi_alloc_master);
+
+/**
+ * spi_register_master - register SPI master controller
+ * @master: initialized master, originally from spi_alloc_master()
+ * Context: can sleep
+ *
+ * SPI master 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_master() 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 master's refcount).
+ * After a successful return, the caller is responsible for calling
+ * spi_unregister_master().
+ */
+int spi_register_master(struct spi_master *master)
+{
+ static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1);
+ struct device *dev = master->dev.parent;
+ int status = -ENODEV;
+ int dynamic = 0;
+
+ if (!dev)
+ return -ENODEV;
+
+ /* even if it's just one always-selected device, there must
+ * be at least one chipselect
+ */
+ if (master->num_chipselect == 0)
+ return -EINVAL;
+
+ /* convention: dynamically assigned bus IDs count down from the max */
+ if (master->bus_num < 0) {
+ /* FIXME switch to an IDR based scheme, something like
+ * I2C now uses, so we can't run out of "dynamic" IDs
+ */
+ master->bus_num = atomic_dec_return(&dyn_bus_id);
+ dynamic = 1;
+ }
+
+ /* register the device, then userspace will see it.
+ * registration fails if the bus ID is in use.
+ */
+ snprintf(master->dev.bus_id, sizeof master->dev.bus_id,
+ "spi%u", master->bus_num);
+ status = device_add(&master->dev);
+ if (status < 0)
+ goto done;
+ dev_dbg(dev, "registered master %s%s\n", master->dev.bus_id,
+ dynamic ? " (dynamic)" : "");
+
+ /* populate children from any spi device tables */
+ scan_boardinfo(master);
+ status = 0;
+done:
+ return status;
+}
+EXPORT_SYMBOL_GPL(spi_register_master);
+
+
+static int __unregister(struct device *dev, void *master_dev)
+{
+ /* note: before about 2.6.14-rc1 this would corrupt memory: */
+ if (dev != master_dev)
+ spi_unregister_device(to_spi_device(dev));
+ return 0;
+}
+
+/**
+ * spi_unregister_master - unregister SPI master controller
+ * @master: the master being unregistered
+ * Context: can sleep
+ *
+ * This call is used only by SPI master controller drivers, which are the
+ * only ones directly touching chip registers.
+ *
+ * This must be called from context that can sleep.
+ */
+void spi_unregister_master(struct spi_master *master)
+{
+ int dummy;
+
+ dummy = device_for_each_child(master->dev.parent, &master->dev,
+ __unregister);
+ device_unregister(&master->dev);
+}
+EXPORT_SYMBOL_GPL(spi_unregister_master);
+
+static int __spi_master_match(struct device *dev, void *data)
+{
+ struct spi_master *m;
+ u16 *bus_num = data;
+
+ m = container_of(dev, struct spi_master, dev);
+ return m->bus_num == *bus_num;
+}
+
+/**
+ * spi_busnum_to_master - look up master associated with bus_num
+ * @bus_num: the master's bus number
+ * Context: can sleep
+ *
+ * This call may be used with devices that are registered after
+ * arch init time. It returns a refcounted pointer to the relevant
+ * spi_master (which the caller must release), or NULL if there is
+ * no such master registered.
+ */
+struct spi_master *spi_busnum_to_master(u16 bus_num)
+{
+ struct device *dev;
+ struct spi_master *master = NULL;
+
+ dev = class_find_device(&spi_master_class, &bus_num,
+ __spi_master_match);
+ if (dev)
+ master = container_of(dev, struct spi_master, dev);
+ /* reference got in class_find_device */
+ return master;
+}
+EXPORT_SYMBOL_GPL(spi_busnum_to_master);
+
+
+/*-------------------------------------------------------------------------*/
+
+static void spi_complete(void *arg)
+{
+ complete(arg);
+}
+
+/**
+ * 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.
+ *
+ * It returns zero on success, else a negative error code.
+ */
+int spi_sync(struct spi_device *spi, struct spi_message *message)
+{
+ DECLARE_COMPLETION_ONSTACK(done);
+ int status;
+
+ message->complete = spi_complete;
+ message->context = &done;
+ status = spi_async(spi, message);
+ if (status == 0) {
+ wait_for_completion(&done);
+ status = message->status;
+ }
+ message->context = NULL;
+ return status;
+}
+EXPORT_SYMBOL_GPL(spi_sync);
+
+/* portable code must never pass more than 32 bytes */
+#define SPI_BUFSIZ max(32,SMP_CACHE_BYTES)
+
+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
+ * @n_rx: size of rxbuf, in bytes (need not be dma-safe)
+ * 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;
+ * portable code should never use this for more than 32 bytes.
+ * Performance-sensitive or bulk transfer code should instead use
+ * spi_{async,sync}() calls with dma-safe buffers.
+ */
+int spi_write_then_read(struct spi_device *spi,
+ const u8 *txbuf, unsigned n_tx,
+ u8 *rxbuf, unsigned n_rx)
+{
+ static DEFINE_MUTEX(lock);
+
+ int status;
+ struct spi_message message;
+ struct spi_transfer x[2];
+ u8 *local_buf;
+
+ /* Use preallocated DMA-safe buffer. We can't avoid copying here,
+ * (as a pure convenience thing), but we can keep heap costs
+ * out of the hot path ...
+ */
+ if ((n_tx + n_rx) > SPI_BUFSIZ)
+ return -EINVAL;
+
+ spi_message_init(&message);
+ memset(x, 0, sizeof x);
+ if (n_tx) {
+ x[0].len = n_tx;
+ spi_message_add_tail(&x[0], &message);
+ }
+ if (n_rx) {
+ x[1].len = n_rx;
+ spi_message_add_tail(&x[1], &message);
+ }
+
+ /* ... unless someone else is using the pre-allocated buffer */
+ if (!mutex_trylock(&lock)) {
+ local_buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL);
+ if (!local_buf)
+ return -ENOMEM;
+ } else
+ local_buf = buf;
+
+ memcpy(local_buf, txbuf, n_tx);
+ x[0].tx_buf = local_buf;
+ x[1].rx_buf = local_buf + n_tx;
+
+ /* do the i/o */
+ status = spi_sync(spi, &message);
+ if (status == 0)
+ memcpy(rxbuf, x[1].rx_buf, n_rx);
+
+ if (x[0].tx_buf == buf)
+ mutex_unlock(&lock);
+ else
+ kfree(local_buf);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(spi_write_then_read);
+
+/*-------------------------------------------------------------------------*/
+
+static int __init spi_init(void)
+{
+ int status;
+
+ buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL);
+ if (!buf) {
+ status = -ENOMEM;
+ goto err0;
+ }
+
+ status = bus_register(&spi_bus_type);
+ if (status < 0)
+ goto err1;
+
+ status = class_register(&spi_master_class);
+ if (status < 0)
+ goto err2;
+ return 0;
+
+err2:
+ bus_unregister(&spi_bus_type);
+err1:
+ kfree(buf);
+ buf = NULL;
+err0:
+ return status;
+}
+
+/* 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.
+ */
+subsys_initcall(spi_init);
+
diff --git a/polux/linux-2.6.10/include/linux/spi/flash.h b/polux/linux-2.6.10/include/linux/spi/flash.h
new file mode 100644
index 0000000000..3f22932e67
--- /dev/null
+++ b/polux/linux-2.6.10/include/linux/spi/flash.h
@@ -0,0 +1,31 @@
+#ifndef LINUX_SPI_FLASH_H
+#define LINUX_SPI_FLASH_H
+
+struct mtd_partition;
+
+/**
+ * struct flash_platform_data: board-specific flash data
+ * @name: optional flash device name (eg, as used with mtdparts=)
+ * @parts: optional array of mtd_partitions for static partitioning
+ * @nr_parts: number of mtd_partitions for static partitoning
+ * @type: optional flash device type (e.g. m25p80 vs m25p64), for use
+ * with chips that can't be queried for JEDEC or other IDs
+ *
+ * Board init code (in arch/.../mach-xxx/board-yyy.c files) can
+ * provide information about SPI flash parts (such as DataFlash) to
+ * help set up the device and its appropriate default partitioning.
+ *
+ * Note that for DataFlash, sizes for pages, blocks, and sectors are
+ * rarely powers of two; and partitions should be sector-aligned.
+ */
+struct flash_platform_data {
+ char *name;
+ struct mtd_partition *parts;
+ unsigned int nr_parts;
+
+ char *type;
+
+ /* we'll likely add more ... use JEDEC IDs, etc */
+};
+
+#endif
diff --git a/polux/linux-2.6.10/include/linux/spi/spi.h b/polux/linux-2.6.10/include/linux/spi/spi.h
new file mode 100644
index 0000000000..387e428f1c
--- /dev/null
+++ b/polux/linux-2.6.10/include/linux/spi/spi.h
@@ -0,0 +1,792 @@
+/*
+ * Copyright (C) 2005 David Brownell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef __LINUX_SPI_H
+#define __LINUX_SPI_H
+
+/*
+ * INTERFACES between SPI master-side drivers and SPI infrastructure.
+ * (There's no SPI slave support for Linux yet...)
+ */
+extern struct bus_type spi_bus_type;
+
+/**
+ * struct spi_device - Master side proxy for an SPI slave device
+ * @dev: Driver model representation of the device.
+ * @master: SPI controller used with the device.
+ * @max_speed_hz: Maximum clock rate to be used with this chip
+ * (on this board); may be changed by the device's driver.
+ * The spi_transfer.speed_hz can override this for each transfer.
+ * @chip_select: Chipselect, distinguishing chips handled by @master.
+ * @mode: The spi mode defines how data is clocked out and in.
+ * This may be changed by the device's driver.
+ * The "active low" default for chipselect mode can be overridden
+ * (by specifying SPI_CS_HIGH) as can the "MSB first" default for
+ * each word in a transfer (by specifying SPI_LSB_FIRST).
+ * @bits_per_word: Data transfers involve one or more words; word sizes
+ * like eight or 12 bits are common. In-memory wordsizes are
+ * powers of two bytes (e.g. 20 bit samples use 32 bits).
+ * This may be changed by the device's driver, or left at the
+ * default (0) indicating protocol words are eight bit bytes.
+ * The spi_transfer.bits_per_word can override this for each transfer.
+ * @irq: Negative, or the number passed to request_irq() to receive
+ * interrupts from this device.
+ * @controller_state: Controller's runtime state
+ * @controller_data: Board-specific definitions for controller, such as
+ * FIFO initialization parameters; from board_info.controller_data
+ * @modalias: Name of the driver to use with this device, or an alias
+ * for that name. This appears in the sysfs "modalias" attribute
+ * for driver coldplugging, and in uevents used for hotplugging
+ *
+ * A @spi_device is used to interchange data between an SPI slave
+ * (usually a discrete chip) and CPU memory.
+ *
+ * In @dev, the platform_data is used to hold information about this
+ * device that's meaningful to the device's protocol driver, but not
+ * to its controller. One example might be an identifier for a chip
+ * variant with slightly different functionality; another might be
+ * information about how this particular board wires the chip's pins.
+ */
+struct spi_device {
+ struct device dev;
+ struct spi_master *master;
+ u32 max_speed_hz;
+ u8 chip_select;
+ u8 mode;
+#define SPI_CPHA 0x01 /* clock phase */
+#define SPI_CPOL 0x02 /* clock polarity */
+#define SPI_MODE_0 (0|0) /* (original MicroWire) */
+#define SPI_MODE_1 (0|SPI_CPHA)
+#define SPI_MODE_2 (SPI_CPOL|0)
+#define SPI_MODE_3 (SPI_CPOL|SPI_CPHA)
+#define SPI_CS_HIGH 0x04 /* chipselect active high? */
+#define SPI_LSB_FIRST 0x08 /* per-word bits-on-wire */
+#define SPI_3WIRE 0x10 /* SI/SO signals shared */
+#define SPI_LOOP 0x20 /* loopback mode */
+ u8 bits_per_word;
+ int irq;
+ void *controller_state;
+ void *controller_data;
+ const char *modalias;
+
+ /*
+ * likely need more hooks for more protocol options affecting how
+ * the controller talks to each chip, like:
+ * - memory packing (12 bit samples into low bits, others zeroed)
+ * - priority
+ * - drop chipselect after each word
+ * - chipselect delays
+ * - ...
+ */
+};
+
+static inline struct spi_device *to_spi_device(struct device *dev)
+{
+ return dev ? container_of(dev, struct spi_device, dev) : NULL;
+}
+
+/* most drivers won't need to care about device refcounting */
+static inline struct spi_device *spi_dev_get(struct spi_device *spi)
+{
+ return (spi && get_device(&spi->dev)) ? spi : NULL;
+}
+
+static inline void spi_dev_put(struct spi_device *spi)
+{
+ if (spi)
+ put_device(&spi->dev);
+}
+
+/* ctldata is for the bus_master driver's runtime state */
+static inline void *spi_get_ctldata(struct spi_device *spi)
+{
+ return spi->controller_state;
+}
+
+static inline void spi_set_ctldata(struct spi_device *spi, void *state)
+{
+ spi->controller_state = state;
+}
+
+/* device driver data */
+
+static inline void spi_set_drvdata(struct spi_device *spi, void *data)
+{
+ dev_set_drvdata(&spi->dev, data);
+}
+
+static inline void *spi_get_drvdata(struct spi_device *spi)
+{
+ return dev_get_drvdata(&spi->dev);
+}
+
+struct spi_message;
+
+
+
+/**
+ * struct spi_driver - Host side "protocol" driver
+ * @probe: Binds this driver to the spi device. Drivers can verify
+ * that the device is actually present, and may need to configure
+ * characteristics (such as bits_per_word) which weren't needed for
+ * the initial configuration done during system setup.
+ * @remove: Unbinds this driver from the spi device
+ * @shutdown: Standard shutdown callback used during system state
+ * transitions such as powerdown/halt and kexec
+ * @suspend: Standard suspend callback used during system state transitions
+ * @resume: Standard resume callback used during system state transitions
+ * @driver: SPI device drivers should initialize the name and owner
+ * field of this structure.
+ *
+ * This represents the kind of device driver that uses SPI messages to
+ * interact with the hardware at the other end of a SPI link. It's called
+ * a "protocol" driver because it works through messages rather than talking
+ * directly to SPI hardware (which is what the underlying SPI controller
+ * driver does to pass those messages). These protocols are defined in the
+ * specification for the device(s) supported by the driver.
+ *
+ * As a rule, those device protocols represent the lowest level interface
+ * supported by a driver, and it will support upper level interfaces too.
+ * Examples of such upper levels include frameworks like MTD, networking,
+ * MMC, RTC, filesystem character device nodes, and hardware monitoring.
+ */
+struct spi_driver {
+ int (*probe)(struct spi_device *spi);
+ int (*remove)(struct spi_device *spi);
+ void (*shutdown)(struct spi_device *spi);
+ int (*suspend)(struct spi_device *spi, pm_message_t mesg);
+ int (*resume)(struct spi_device *spi);
+ struct device_driver driver;
+};
+
+static inline struct spi_driver *to_spi_driver(struct device_driver *drv)
+{
+ return drv ? container_of(drv, struct spi_driver, driver) : NULL;
+}
+
+extern int spi_register_driver(struct spi_driver *sdrv);
+
+/**
+ * spi_unregister_driver - reverse effect of spi_register_driver
+ * @sdrv: the driver to unregister
+ * Context: can sleep
+ */
+static inline void spi_unregister_driver(struct spi_driver *sdrv)
+{
+ if (sdrv)
+ driver_unregister(&sdrv->driver);
+}
+
+
+/**
+ * struct spi_master - interface to SPI master controller
+ * @dev: device interface to this driver
+ * @bus_num: board-specific (and often SOC-specific) identifier for a
+ * given SPI controller.
+ * @num_chipselect: chipselects are used to distinguish individual
+ * SPI slaves, and are numbered from zero to num_chipselects.
+ * each slave has a chipselect signal, but it's common that not
+ * every chipselect is connected to a slave.
+ * @setup: updates the device mode and clocking records used by a
+ * device's SPI controller; protocol code may call this. This
+ * must fail if an unrecognized or unsupported mode is requested.
+ * It's always safe to call this unless transfers are pending on
+ * the device whose settings are being modified.
+ * @transfer: adds a message to the controller's transfer queue.
+ * @cleanup: frees controller-specific state
+ *
+ * Each SPI master controller can communicate with one or more @spi_device
+ * children. These make a small bus, sharing MOSI, MISO and SCK signals
+ * but not chip select signals. Each device may be configured to use a
+ * different clock rate, since those shared signals are ignored unless
+ * the chip is selected.
+ *
+ * The driver for an SPI controller manages access to those devices through
+ * a queue of spi_message transactions, copying data between CPU memory and
+ * an SPI slave device. For each such message it queues, it calls the
+ * message's completion function when the transaction completes.
+ */
+struct spi_master {
+ struct device dev;
+
+ /* other than negative (== assign one dynamically), bus_num is fully
+ * board-specific. usually that simplifies to being SOC-specific.
+ * example: one SOC has three SPI controllers, numbered 0..2,
+ * and one board's schematics might show it using SPI-2. software
+ * would normally use bus_num=2 for that controller.
+ */
+ s16 bus_num;
+
+ /* chipselects will be integral to many controllers; some others
+ * might use board-specific GPIOs.
+ */
+ u16 num_chipselect;
+
+ /* setup mode and clock, etc (spi driver may call many times) */
+ int (*setup)(struct spi_device *spi);
+
+ /* bidirectional bulk transfers
+ *
+ * + The transfer() method may not sleep; its main role is
+ * just to add the message to the queue.
+ * + For now there's no remove-from-queue operation, or
+ * any other request management
+ * + To a given spi_device, message queueing is pure fifo
+ *
+ * + The master's main job is to process its message queue,
+ * selecting a chip then transferring data
+ * + If there are multiple spi_device children, the i/o queue
+ * arbitration algorithm is unspecified (round robin, fifo,
+ * priority, reservations, preemption, etc)
+ *
+ * + Chipselect stays active during the entire message
+ * (unless modified by spi_transfer.cs_change != 0).
+ * + The message transfers use clock and SPI mode parameters
+ * previously established by setup() for this device
+ */
+ int (*transfer)(struct spi_device *spi,
+ struct spi_message *mesg);
+
+ /* called on release() to free memory provided by spi_master */
+ void (*cleanup)(struct spi_device *spi);
+};
+
+static inline void *spi_master_get_devdata(struct spi_master *master)
+{
+ return dev_get_drvdata(&master->dev);
+}
+
+static inline void spi_master_set_devdata(struct spi_master *master, void *data)
+{
+ dev_set_drvdata(&master->dev, data);
+}
+
+static inline struct spi_master *spi_master_get(struct spi_master *master)
+{
+ if (!master || !get_device(&master->dev))
+ return NULL;
+ return master;
+}
+
+static inline void spi_master_put(struct spi_master *master)
+{
+ if (master)
+ put_device(&master->dev);
+}
+
+
+/* the spi driver core manages memory for the spi_master classdev */
+extern struct spi_master *
+spi_alloc_master(struct device *host, unsigned size);
+
+extern int spi_register_master(struct spi_master *master);
+extern void spi_unregister_master(struct spi_master *master);
+
+extern struct spi_master *spi_busnum_to_master(u16 busnum);
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * I/O INTERFACE between SPI controller and protocol drivers
+ *
+ * Protocol drivers use a queue of spi_messages, each transferring data
+ * between the controller and memory buffers.
+ *
+ * The spi_messages themselves consist of a series of read+write transfer
+ * segments. Those segments always read the same number of bits as they
+ * write; but one or the other is easily ignored by passing a null buffer
+ * pointer. (This is unlike most types of I/O API, because SPI hardware
+ * is full duplex.)
+ *
+ * NOTE: Allocation of spi_transfer and spi_message memory is entirely
+ * up to the protocol driver, which guarantees the integrity of both (as
+ * well as the data buffers) for as long as the message is queued.
+ */
+
+/**
+ * struct spi_transfer - a read/write buffer pair
+ * @tx_buf: data to be written (dma-safe memory), or NULL
+ * @rx_buf: data to be read (dma-safe memory), or NULL
+ * @tx_dma: DMA address of tx_buf, if @spi_message.is_dma_mapped
+ * @rx_dma: DMA address of rx_buf, if @spi_message.is_dma_mapped
+ * @len: size of rx and tx buffers (in bytes)
+ * @speed_hz: Select a speed other then the device default for this
+ * transfer. If 0 the default (from @spi_device) is used.
+ * @bits_per_word: select a bits_per_word other then the device default
+ * for this transfer. If 0 the default (from @spi_device) is used.
+ * @cs_change: affects chipselect after this transfer completes
+ * @delay_usecs: microseconds to delay after this transfer before
+ * (optionally) changing the chipselect status, then starting
+ * the next transfer or completing this @spi_message.
+ * @transfer_list: transfers are sequenced through @spi_message.transfers
+ *
+ * SPI transfers always write the same number of bytes as they read.
+ * Protocol drivers should always provide @rx_buf and/or @tx_buf.
+ * In some cases, they may also want to provide DMA addresses for
+ * the data being transferred; that may reduce overhead, when the
+ * underlying driver uses dma.
+ *
+ * If the transmit buffer is null, zeroes will be shifted out
+ * while filling @rx_buf. If the receive buffer is null, the data
+ * shifted in will be discarded. Only "len" bytes shift out (or in).
+ * It's an error to try to shift out a partial word. (For example, by
+ * shifting out three bytes with word size of sixteen or twenty bits;
+ * the former uses two bytes per word, the latter uses four bytes.)
+ *
+ * In-memory data values are always in native CPU byte order, translated
+ * from the wire byte order (big-endian except with SPI_LSB_FIRST). So
+ * for example when bits_per_word is sixteen, buffers are 2N bytes long
+ * (@len = 2N) and hold N sixteen bit words in CPU byte order.
+ *
+ * When the word size of the SPI transfer is not a power-of-two multiple
+ * of eight bits, those in-memory words include extra bits. In-memory
+ * words are always seen by protocol drivers as right-justified, so the
+ * undefined (rx) or unused (tx) bits are always the most significant bits.
+ *
+ * All SPI transfers start with the relevant chipselect active. Normally
+ * it stays selected until after the last transfer in a message. Drivers
+ * can affect the chipselect signal using cs_change.
+ *
+ * (i) If the transfer isn't the last one in the message, this flag is
+ * used to make the chipselect briefly go inactive in the middle of the
+ * message. Toggling chipselect in this way may be needed to terminate
+ * a chip command, letting a single spi_message perform all of group of
+ * chip transactions together.
+ *
+ * (ii) When the transfer is the last one in the message, the chip may
+ * stay selected until the next transfer. On multi-device SPI busses
+ * with nothing blocking messages going to other devices, this is just
+ * a performance hint; starting a message to another device deselects
+ * this one. But in other cases, this can be used to ensure correctness.
+ * Some devices need protocol transactions to be built from a series of
+ * spi_message submissions, where the content of one message is determined
+ * by the results of previous messages and where the whole transaction
+ * ends when the chipselect goes intactive.
+ *
+ * The code that submits an spi_message (and its spi_transfers)
+ * to the lower layers is responsible for managing its memory.
+ * Zero-initialize every field you don't set up explicitly, to
+ * insulate against future API updates. After you submit a message
+ * and its transfers, ignore them until its completion callback.
+ */
+struct spi_transfer {
+ /* it's ok if tx_buf == rx_buf (right?)
+ * for MicroWire, one buffer must be null
+ * buffers must work with dma_*map_single() calls, unless
+ * spi_message.is_dma_mapped reports a pre-existing mapping
+ */
+ const void *tx_buf;
+ void *rx_buf;
+ unsigned len;
+
+ dma_addr_t tx_dma;
+ dma_addr_t rx_dma;
+
+ unsigned cs_change:1;
+ u8 bits_per_word;
+ u16 delay_usecs;
+ u32 speed_hz;
+
+ struct list_head transfer_list;
+};
+
+/**
+ * struct spi_message - one multi-segment SPI transaction
+ * @transfers: list of transfer segments in this transaction
+ * @spi: SPI device to which the transaction is queued
+ * @is_dma_mapped: if true, the caller provided both dma and cpu virtual
+ * addresses for each transfer buffer
+ * @complete: called to report transaction completions
+ * @context: the argument to complete() when it's called
+ * @actual_length: the total number of bytes that were transferred in all
+ * successful segments
+ * @status: zero for success, else negative errno
+ * @queue: for use by whichever driver currently owns the message
+ * @state: for use by whichever driver currently owns the message
+ *
+ * A @spi_message is used to execute an atomic sequence of data transfers,
+ * each represented by a struct spi_transfer. The sequence is "atomic"
+ * in the sense that no other spi_message may use that SPI bus until that
+ * sequence completes. On some systems, many such sequences can execute as
+ * as single programmed DMA transfer. On all systems, these messages are
+ * queued, and might complete after transactions to other devices. Messages
+ * sent to a given spi_device are alway executed in FIFO order.
+ *
+ * The code that submits an spi_message (and its spi_transfers)
+ * to the lower layers is responsible for managing its memory.
+ * Zero-initialize every field you don't set up explicitly, to
+ * insulate against future API updates. After you submit a message
+ * and its transfers, ignore them until its completion callback.
+ */
+struct spi_message {
+ struct list_head transfers;
+
+ struct spi_device *spi;
+
+ unsigned is_dma_mapped:1;
+
+ /* REVISIT: we might want a flag affecting the behavior of the
+ * last transfer ... allowing things like "read 16 bit length L"
+ * immediately followed by "read L bytes". Basically imposing
+ * a specific message scheduling algorithm.
+ *
+ * Some controller drivers (message-at-a-time queue processing)
+ * could provide that as their default scheduling algorithm. But
+ * others (with multi-message pipelines) could need a flag to
+ * tell them about such special cases.
+ */
+
+ /* completion is reported through a callback */
+ void (*complete)(void *context);
+ void *context;
+ unsigned actual_length;
+ int status;
+
+ /* for optional use by whatever driver currently owns the
+ * spi_message ... between calls to spi_async and then later
+ * complete(), that's the spi_master controller driver.
+ */
+ struct list_head queue;
+ void *state;
+};
+
+static inline void spi_message_init(struct spi_message *m)
+{
+ memset(m, 0, sizeof *m);
+ INIT_LIST_HEAD(&m->transfers);
+}
+
+static inline void
+spi_message_add_tail(struct spi_transfer *t, struct spi_message *m)
+{
+ list_add_tail(&t->transfer_list, &m->transfers);
+}
+
+static inline void
+spi_transfer_del(struct spi_transfer *t)
+{
+ list_del(&t->transfer_list);
+}
+
+/* It's fine to embed message and transaction structures in other data
+ * structures so long as you don't free them while they're in use.
+ */
+
+static inline struct spi_message *spi_message_alloc(unsigned ntrans, gfp_t flags)
+{
+ struct spi_message *m;
+
+ m = kzalloc(sizeof(struct spi_message)
+ + ntrans * sizeof(struct spi_transfer),
+ flags);
+ if (m) {
+ int i;
+ struct spi_transfer *t = (struct spi_transfer *)(m + 1);
+
+ INIT_LIST_HEAD(&m->transfers);
+ for (i = 0; i < ntrans; i++, t++)
+ spi_message_add_tail(t, m);
+ }
+ return m;
+}
+
+static inline void spi_message_free(struct spi_message *m)
+{
+ kfree(m);
+}
+
+/**
+ * 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.
+ */
+static inline int
+spi_setup(struct spi_device *spi)
+{
+ return spi->master->setup(spi);
+}
+
+
+/**
+ * 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.)
+ */
+static inline int
+spi_async(struct spi_device *spi, struct spi_message *message)
+{
+ message->spi = spi;
+ return spi->master->transfer(spi, message);
+}
+
+/*---------------------------------------------------------------------------*/
+
+/* All these synchronous SPI transfer routines are utilities layered
+ * over the core async transfer primitive. Here, "synchronous" means
+ * they will sleep uninterruptibly until the async transfer completes.
+ */
+
+extern int spi_sync(struct spi_device *spi, struct spi_message *message);
+
+/**
+ * spi_write - SPI synchronous write
+ * @spi: device to which data will be written
+ * @buf: data buffer
+ * @len: data buffer size
+ * Context: can sleep
+ *
+ * This writes the buffer and returns zero or a negative error code.
+ * Callable only from contexts that can sleep.
+ */
+static inline int
+spi_write(struct spi_device *spi, const u8 *buf, size_t len)
+{
+ struct spi_transfer t = {
+ .tx_buf = buf,
+ .len = len,
+ };
+ struct spi_message m;
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+ return spi_sync(spi, &m);
+}
+
+/**
+ * spi_read - SPI synchronous read
+ * @spi: device from which data will be read
+ * @buf: data buffer
+ * @len: data buffer size
+ * Context: can sleep
+ *
+ * This reads the buffer and returns zero or a negative error code.
+ * Callable only from contexts that can sleep.
+ */
+static inline int
+spi_read(struct spi_device *spi, u8 *buf, size_t len)
+{
+ struct spi_transfer t = {
+ .rx_buf = buf,
+ .len = len,
+ };
+ struct spi_message m;
+
+ spi_message_init(&m);
+ spi_message_add_tail(&t, &m);
+ return spi_sync(spi, &m);
+}
+
+/* this copies txbuf and rxbuf data; for small transfers only! */
+extern int spi_write_then_read(struct spi_device *spi,
+ const u8 *txbuf, unsigned n_tx,
+ u8 *rxbuf, unsigned n_rx);
+
+/**
+ * spi_w8r8 - SPI synchronous 8 bit write followed by 8 bit read
+ * @spi: device with which data will be exchanged
+ * @cmd: command to be written before data is read back
+ * Context: can sleep
+ *
+ * This returns the (unsigned) eight bit number returned by the
+ * device, or else a negative error code. Callable only from
+ * contexts that can sleep.
+ */
+static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd)
+{
+ ssize_t status;
+ u8 result;
+
+ status = spi_write_then_read(spi, &cmd, 1, &result, 1);
+
+ /* return negative errno or unsigned value */
+ return (status < 0) ? status : result;
+}
+
+/**
+ * spi_w8r16 - SPI synchronous 8 bit write followed by 16 bit read
+ * @spi: device with which data will be exchanged
+ * @cmd: command to be written before data is read back
+ * Context: can sleep
+ *
+ * This returns the (unsigned) sixteen bit number returned by the
+ * device, or else a negative error code. Callable only from
+ * contexts that can sleep.
+ *
+ * The number is returned in wire-order, which is at least sometimes
+ * big-endian.
+ */
+static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd)
+{
+ ssize_t status;
+ u16 result;
+
+ status = spi_write_then_read(spi, &cmd, 1, (u8 *) &result, 2);
+
+ /* return negative errno or unsigned value */
+ return (status < 0) ? status : result;
+}
+
+/*---------------------------------------------------------------------------*/
+
+/*
+ * INTERFACE between board init code and SPI infrastructure.
+ *
+ * No SPI driver ever sees these SPI device table segments, but
+ * it's how the SPI core (or adapters that get hotplugged) grows
+ * the driver model tree.
+ *
+ * As a rule, SPI devices can't be probed. Instead, board init code
+ * provides a table listing the devices which are present, with enough
+ * information to bind and set up the device's driver. There's basic
+ * support for nonstatic configurations too; enough to handle adding
+ * parport adapters, or microcontrollers acting as USB-to-SPI bridges.
+ */
+
+/**
+ * struct spi_board_info - board-specific template for a SPI device
+ * @modalias: Initializes spi_device.modalias; identifies the driver.
+ * @platform_data: Initializes spi_device.platform_data; the particular
+ * data stored there is driver-specific.
+ * @controller_data: Initializes spi_device.controller_data; some
+ * controllers need hints about hardware setup, e.g. for DMA.
+ * @irq: Initializes spi_device.irq; depends on how the board is wired.
+ * @max_speed_hz: Initializes spi_device.max_speed_hz; based on limits
+ * from the chip datasheet and board-specific signal quality issues.
+ * @bus_num: Identifies which spi_master parents the spi_device; unused
+ * by spi_new_device(), and otherwise depends on board wiring.
+ * @chip_select: Initializes spi_device.chip_select; depends on how
+ * the board is wired.
+ * @mode: Initializes spi_device.mode; based on the chip datasheet, board
+ * wiring (some devices support both 3WIRE and standard modes), and
+ * possibly presence of an inverter in the chipselect path.
+ *
+ * When adding new SPI devices to the device tree, these structures serve
+ * as a partial device template. They hold information which can't always
+ * be determined by drivers. Information that probe() can establish (such
+ * as the default transfer wordsize) is not included here.
+ *
+ * These structures are used in two places. Their primary role is to
+ * be stored in tables of board-specific device descriptors, which are
+ * declared early in board initialization and then used (much later) to
+ * populate a controller's device tree after the that controller's driver
+ * initializes. A secondary (and atypical) role is as a parameter to
+ * spi_new_device() call, which happens after those controller drivers
+ * are active in some dynamic board configuration models.
+ */
+struct spi_board_info {
+ /* the device name and module name are coupled, like platform_bus;
+ * "modalias" is normally the driver name.
+ *
+ * platform_data goes to spi_device.dev.platform_data,
+ * controller_data goes to spi_device.controller_data,
+ * irq is copied too
+ */
+ char modalias[KOBJ_NAME_LEN];
+ const void *platform_data;
+ void *controller_data;
+ int irq;
+
+ /* slower signaling on noisy or low voltage boards */
+ u32 max_speed_hz;
+
+
+ /* bus_num is board specific and matches the bus_num of some
+ * spi_master that will probably be registered later.
+ *
+ * chip_select reflects how this chip is wired to that master;
+ * it's less than num_chipselect.
+ */
+ u16 bus_num;
+ u16 chip_select;
+
+ /* mode becomes spi_device.mode, and is essential for chips
+ * where the default of SPI_CS_HIGH = 0 is wrong.
+ */
+ u8 mode;
+
+ /* ... may need additional spi_device chip config data here.
+ * avoid stuff protocol drivers can set; but include stuff
+ * needed to behave without being bound to a driver:
+ * - quirks like clock rate mattering when not selected
+ */
+};
+
+#ifdef CONFIG_SPI
+extern int
+spi_register_board_info(struct spi_board_info const *info, unsigned n);
+#else
+/* board init code may ignore whether SPI is configured or not */
+static inline int
+spi_register_board_info(struct spi_board_info const *info, unsigned n)
+ { return 0; }
+#endif
+
+
+/* If you're hotplugging an adapter with devices (parport, usb, etc)
+ * use spi_new_device() to describe each device. You can also call
+ * spi_unregister_device() to start making that device vanish, but
+ * normally that would be handled by spi_unregister_master().
+ */
+extern struct spi_device *
+spi_new_device(struct spi_master *, struct spi_board_info *);
+
+static inline void
+spi_unregister_device(struct spi_device *spi)
+{
+ if (spi)
+ device_unregister(&spi->dev);
+}
+
+#endif /* __LINUX_SPI_H */