linux/drivers
Haavard Skinnemoen dc0ee6435c dmaengine: Add slave DMA interface
This patch adds the necessary interfaces to the DMA Engine framework
to use functionality found on most embedded DMA controllers: DMA from
and to I/O registers with hardware handshaking.

In this context, hardware hanshaking means that the peripheral that
owns the I/O registers in question is able to tell the DMA controller
when more data is available for reading, or when there is room for
more data to be written. This usually happens internally on the chip,
but these signals may also be exported outside the chip for things
like IDE DMA, etc.

A new struct dma_slave is introduced. This contains information that
the DMA engine driver needs to set up slave transfers to and from a
slave device. Most engines supporting DMA slave transfers will want to
extend this structure with controller-specific parameters.  This
additional information is usually passed from the platform/board code
through the client driver.

A "slave" pointer is added to the dma_client struct. This must point
to a valid dma_slave structure iff the DMA_SLAVE capability is
requested.  The DMA engine driver may use this information in its
device_alloc_chan_resources hook to configure the DMA controller for
slave transfers from and to the given slave device.

A new operation for preparing slave DMA transfers is added to struct
dma_device. This takes a scatterlist and returns a single descriptor
representing the whole transfer.

Another new operation for terminating all pending transfers is added as
well. The latter is needed because there may be errors outside the scope
of the DMA Engine framework that may require DMA operations to be
terminated prematurely.

DMA Engine drivers may extend the dma_device, dma_chan and/or
dma_slave_descriptor structures to allow controller-specific
operations. The client driver can detect such extensions by looking at
the DMA Engine's struct device, or it can request a specific DMA
Engine device by setting the dma_dev field in struct dma_slave.

dmaslave interface changes since v4:
  * Fix checkpatch errors
  * Fix changelog (there are no slave descriptors anymore)

dmaslave interface changes since v3:
  * Use dma_data_direction instead of a new enum
  * Submit slave transfers as scatterlists
  * Remove the DMA slave descriptor struct

dmaslave interface changes since v2:
  * Add a dma_dev field to struct dma_slave. If set, the client can
    only be bound to the DMA controller that corresponds to this
    device.  This allows controller-specific extensions of the
    dma_slave structure; if the device matches, the controller may
    safely assume its extensions are present.
  * Move reg_width into struct dma_slave as there are currently no
    users that need to be able to set the width on a per-transfer
    basis.

dmaslave interface changes since v1:
  * Drop the set_direction and set_width descriptor hooks. Pass the
    direction and width to the prep function instead.
  * Declare a dma_slave struct with fixed information about a slave,
    i.e. register addresses, handshake interfaces and such.
  * Add pointer to a dma_slave struct to dma_client. Can be NULL if
    the DMA_SLAVE capability isn't requested.
  * Drop the set_slave device hook since the alloc_chan_resources hook
    now has enough information to set up the channel for slave
    transfers.

Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08 11:59:35 -07:00
..
accessibility Kconfig: improved help for CONFIG_ACCESSIBILITY 2008-05-08 10:46:55 -07:00
acorn/char
acpi acpi: fix integer as NULL pointer warning 2008-05-23 08:11:06 -07:00
amba
ata drivers/ata: trim trailing whitespace 2008-05-19 17:56:10 -04:00
atm drivers/atm/: remove CVS keywords 2008-05-20 14:52:25 -07:00
auxdisplay
base Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-05-20 17:23:03 -07:00
block brd: don't show ramdisks in /proc/partitions 2008-05-24 09:56:11 -07:00
bluetooth hci_usb.h: fix hard-to-trigger race 2008-05-02 16:45:10 -07:00
cdrom [POWERPC] iSeries: Remove unused mail address 2008-05-23 16:45:04 +10:00
char ip2: fix crashes on load/unload 2008-05-24 09:56:11 -07:00
clocksource
connector
cpufreq [CPUFREQ] clarify license of freq_table.c 2008-05-22 16:38:03 -04:00
cpuidle cpuidle: fix 100% C0 statistics regression 2008-03-26 00:58:19 -04:00
crypto [CRYPTO] padlock-aes: Use generic setkey function 2008-04-21 10:19:34 +08:00
dca
dio
dma dmaengine: Add slave DMA interface 2008-07-08 11:59:35 -07:00
edac edac: mpc85xx: fix building as a module 2008-05-24 09:56:13 -07:00
eisa
firewire firewire: prevent userspace from accessing shut down devices 2008-05-20 18:24:17 +02:00
firmware edd: add default mode CONFIG_EDD_OFF=n, override with edd={on,off} 2008-04-29 08:06:23 -07:00
gpio gpiolib: fix off by one errors 2008-05-24 09:56:11 -07:00
hid HID: remove CVS keywords 2008-05-20 16:44:43 +02:00
hwmon ibmaem: new driver for power/energy/temp meters in IBM System X hardware 2008-05-24 09:56:08 -07:00
i2c i2c/max6875: Really prevent 24RF08 corruption 2008-05-18 20:49:41 +02:00
ide ide: fix race in device_create 2008-05-20 13:31:54 -07:00
ieee1394 ieee1394: sbp2: use correct size of command descriptor block 2008-05-20 18:24:17 +02:00
infiniband Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband 2008-05-23 11:11:44 -07:00
input MODULE_LICENSE expects "GPL v2", not "GPLv2" 2008-05-21 16:56:00 -07:00
isdn isdn: fix integer as NULL pointer warning 2008-05-23 08:11:06 -07:00
leds LEDS: fix race in device_create 2008-05-20 13:31:55 -07:00
lguest lguest: make Launcher see device status updates 2008-05-02 21:50:54 +10:00
macintosh [POWERPC] macintosh: Replace deprecated __initcall with device_initcall 2008-05-15 20:50:00 +10:00
mca proc: remove proc_root from drivers 2008-04-29 08:06:18 -07:00
md md: restart recovery cleanly after device failure. 2008-05-24 09:56:10 -07:00
media tuner: Do not alter i2c_client.name 2008-05-26 16:08:40 +02:00
memstick memstick: convert struct class_device to struct device 2008-04-19 19:10:29 -07:00
message Remove duplicated unlikely() in IS_ERR() 2008-04-29 08:06:25 -07:00
mfd HTC_EGPIO is ARM-only 2008-05-21 16:56:00 -07:00
misc drivers/misc/sgi-xp: replace partid_t with a short 2008-05-13 08:02:23 -07:00
mmc missing dependencies on HAS_DMA 2008-05-21 16:55:59 -07:00
mtd ck804rom: fix driver_data in probe table. 2008-05-27 07:34:38 -07:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2008-05-26 10:14:02 -07:00
nubus proc: convert /proc/bus/nubus to seq_file interface 2008-04-29 08:06:19 -07:00
of [POWERPC] Add null pointer check to of_find_property 2008-05-15 20:49:49 +10:00
oprofile oprofile: don't request cache line alignment for cpu_buffer 2008-05-14 19:11:12 -07:00
parisc drivers/parisc: replace remaining __FUNCTION__ occurrences 2008-05-15 10:38:54 -04:00
parport debugobjects: add timer specific object debugging code 2008-04-30 08:29:53 -07:00
pci pciehp: add message about pciehp_slot_with_bus option 2008-05-27 15:43:47 -07:00
pcmcia pcmcia: replace remaining __FUNCTION__ occurrences 2008-05-01 08:04:00 -07:00
pnp Clean up 'print_fn_descriptor_symbol()' types 2008-05-15 17:50:37 -07:00
power Power Supply: fix race in device_create 2008-05-20 13:31:55 -07:00
ps3 [POWERPC] PS3: Remove unsupported wakeup sources 2008-05-02 15:00:44 +10:00
rapidio [RAPIDIO] Auto-probe the RapidIO system size 2008-04-29 19:40:28 +10:00
rtc rtc: m41t80: include <linux/kernel.h> for printk() 2008-05-13 08:02:26 -07:00
s390 s390: fix race in device_create 2008-05-20 13:31:56 -07:00
sbus sbus bpp: instances missed in s/dev_name/bpp_dev_name/ 2008-05-21 16:55:59 -07:00
scsi scsi: fix integer as NULL pointer warning 2008-05-23 08:11:07 -07:00
serial serial: fix enable_irq_wake/disable_irq_wake imbalance in serial_core.c 2008-05-24 09:56:11 -07:00
sh
sn
spi spi: remove some spidev oops-on-rmmod paths 2008-05-24 09:56:14 -07:00
ssb ssb: Fix all-ones boardflags 2008-04-23 21:25:35 -04:00
tc
telephony
thermal thermal: re-name thermal.c to thermal_sys.c 2008-04-29 03:12:17 -04:00
uio UIO: fix race in device_create 2008-05-20 13:31:55 -07:00
usb Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6 2008-05-20 17:20:49 -07:00
video Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm 2008-05-24 10:13:16 -07:00
virtio virtio: explicit advertisement of driver features 2008-05-02 21:50:50 +10:00
w1 drivers: replace remaining __FUNCTION__ occurrences 2008-04-30 08:29:53 -07:00
watchdog [WATCHDOG] Add ICH9DO into the iTCO_wdt.c driver 2008-05-25 09:45:39 +00:00
xen xen: add balloon driver 2008-04-24 23:57:33 +02:00
zorro zorro: use non-racy method for proc entries creation 2008-04-29 08:06:21 -07:00
Kconfig Basic braille screen reader support 2008-04-30 08:29:52 -07:00
Makefile Basic braille screen reader support 2008-04-30 08:29:52 -07:00