aboutsummaryrefslogtreecommitdiff
path: root/hw/dma
AgeCommit message (Collapse)Author
2014-06-30hw: Fix qemu_allocate_irqs() leaksAndreas Färber
Replace qemu_allocate_irqs(foo, bar, 1)[0] with qemu_allocate_irq(foo, bar, 0). This avoids leaking the dereferenced qemu_irq *. Cc: Markus Armbruster <armbru@redhat.com> Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Andreas Färber <afaerber@suse.de> [PC Changes: * Applied change to instance in sh4/sh7750.c ] Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Kirill Batuzov <batuzovk@ispras.ru> [AF: Fix IRQ index in sh4/sh7750.c] Cc: qemu-stable@nongnu.org Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-06-16savevm: Remove all the unneeded version_minimum_id_old (x86)Juan Quintela
After previous Peter patch, they are redundant. This way we don't assign them except when needed. Once there, there were lots of case where the ".fields" indentation was wrong: .fields = (VMStateField []) { and .fields = (VMStateField []) { Change all the combinations to: .fields = (VMStateField[]){ The biggest problem (appart from aesthetics) was that checkpatch complained when we copy&pasted the code from one place to another. Signed-off-by: Juan Quintela <quintela@redhat.com> Acked-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-10hw/dma/xilinx_axidma: Remove unused stream_halted() functionPeter Maydell
The stream_halted() function is never used; remove it. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-15Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20140515' ↵Peter Maydell
into staging migration/next for 20140515 # gpg: Signature made Thu 15 May 2014 02:32:25 BST using RSA key ID 5872D723 # gpg: Can't check signature: public key not found * remotes/juanquintela/tags/migration/20140515: usb: fix up post load checks migration: show average throughput when migration finishes savevm: Remove all the unneeded version_minimum_id_old (rest) savevm: Remove all the unneeded version_minimum_id_old (usb) Split ram_save_block arch_init: Simplify code for load_xbzrle() Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-14savevm: Remove all the unneeded version_minimum_id_old (rest)Juan Quintela
After previous Peter patch, they are redundant. This way we don't assign them except when needed. Once there, there were lots of case where the ".fields" indentation was wrong: .fields = (VMStateField []) { and .fields = (VMStateField []) { Change all the combinations to: .fields = (VMStateField[]){ The biggest problem (appart from aesthetics) was that checkpatch complained when we copy&pasted the code from one place to another. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-13hw/dma/omap_dma: Add (uint32_t) casts when shifting uint16_t by 16Peter Maydell
Add missing (uint32_t) casts in cases where we're trying to put a uint16_t value into the top half of a 32-bit field. These were already present in some but not all places. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
2014-05-13savevm: Remove all the unneeded version_minimum_id_old (arm)Juan Quintela
After commit 767adce2d, they are redundant. This way we don't assign them except when needed. Once there, there were lots of cases where the ".fields" indentation was wrong: .fields = (VMStateField []) { and .fields = (VMStateField []) { Change all the combinations to: .fields = (VMStateField[]){ The biggest problem (apart from aesthetics) was that checkpatch complained when we copy&pasted the code from one place to another. Signed-off-by: Juan Quintela <quintela@redhat.com> [PMM: fixed minor conflict, corrected commit message typos] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-05-05PortioList: Store PortioList in device stateKirill Batuzov
PortioList is an abstraction used for construction of MemoryRegionPortioList from MemoryRegionPortio. It can be used later to unmap created memory regions. It also requires proper cleanup because some of the memory inside is allocated dynamically. By moving PortioList ot device state we make it possible to cleanup later and avoid leaking memory. This change spans several target platforms. The following testcases cover all changed lines: qemu-system-ppc -M prep qemu-system-i386 -vga qxl qemu-system-i386 -M isapc -soundhw adlib -device ib700,id=watchdog0,bus=isa.0 Signed-off-by: Kirill Batuzov <batuzovk@ispras.ru> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-05-05hw: Consistently name Error * objects err, and not errpMarkus Armbruster
Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-19qom: Add check() argument to object_property_add_link()Stefan Hajnoczi
There are currently three types of object_property_add_link() callers: 1. The link property may be set at any time. 2. The link property of a DeviceState instance may only be set before realize. 3. The link property may never be set, it is read-only. Something similar can already be achieved with object_property_add_str()'s set() argument. Follow its example and add a check() argument to object_property_add_link(). Also provide default check() functions for case #1 and #2. Case #3 is covered by passing a NULL function pointer. Cc: Peter Crosthwaite <peter.crosthwaite@petalogix.com> Cc: Alexander Graf <agraf@suse.de> Cc: Anthony Liguori <aliguori@amazon.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> [AF: Tweaked documentation comment] Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-03-19qom: Make QOM link property unref optionalStefan Hajnoczi
Some object_property_add_link() callers expect property deletion to unref the link property object. Other callers expect to manage the refcount themselves. The former are currently broken and therefore leak the link property object. This patch adds a flags argument to object_property_add_link() so the caller can specify which refcount behavior they require. The new OBJ_PROP_LINK_UNREF_ON_RELEASE flag causes the link pointer to be unreferenced when the property is deleted. This fixes refcount leaks in qdev.c, xilinx_axidma.c, xilinx_axienet.c, s390-virtio-bus.c, virtio-pci.c, virtio-rng.c, and ui/console.c. Rationale for refcount behavior: * hw/core/qdev.c - bus children are explicitly unreferenced, don't interfere - parent_bus is essentially a read-only property that doesn't hold a refcount, don't unref - hotplug_handler is leaked, do unref * hw/dma/xilinx_axidma.c - rx stream "dma" links are set using set_link, therefore they need unref - tx streams are set using set_link, therefore they need unref * hw/net/xilinx_axienet.c - same reasoning as hw/dma/xilinx_axidma.c * hw/pcmcia/pxa2xx.c - pxa2xx bypasses set_link and therefore does not use refcounts * hw/s390x/s390-virtio-bus.c * hw/virtio/virtio-pci.c * hw/virtio/virtio-rng.c * ui/console.c - set_link is used and there is no explicit unref, do unref Cc: Peter Crosthwaite <peter.crosthwaite@petalogix.com> Cc: Alexander Graf <agraf@suse.de> Cc: Anthony Liguori <aliguori@amazon.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-02-26dma/pl330: implement dmaadnh instructionPeter Crosthwaite
Implement the missing DMAADNH instruction. This is a minor variant of the DMAADDH instruction, so factor out to a common implementation for both (dmaadxh). Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Message-id: 73ab13532a7cae53441da89b46c279b5f50785e3.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: Fix buffer depthPeter Crosthwaite
This is the product of the data-width and the depth arguments, I.e the depth of the FIFO is in terms of data entries and not bytes (which is what the original implementation was suggesting). Fix. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: c34de31031511538ccdb3164b48ee8a6a973ebd4.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: Add event debugging printfsPeter Crosthwaite
These are helpful to anyone trying to debug event sequencing. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: e82a0ad804db3de4f46839e55a9d287735ef870d.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: Rename parent_objPeter Crosthwaite
As per current QOM conventions. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: abb137347ea1ee9c31487b544f3d5435fb17f6a4.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: printf format type sweep.Peter Crosthwaite
Use PRI formats as appropriate rather than raw %x and %d. This fixes debug printfery on some host platforms. Fix types of debug only variables as appropriate. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: dbb5f5fd048b2d4a3cb5c6357577d11211a7a585.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: Fix misleading typePeter Crosthwaite
This type really should just be a regular int as no usages rely on it's 32 bitness (it's only meaningful as a bit position and not a bit mask). This also fixes a printf which uses the variable with a regular %d. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 2a99d31f377aee371476d9da8fd0d1b7efa30f63.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-26dma/pl330: Delete overly verbose debug printfPeter Crosthwaite
When using event synchronisation, this particular debug printf floods. Just delete it. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Message-id: dd94d19493f97c47497b9d8caf74ca43e70d58fd.1393372019.git.peter.crosthwaite@xilinx.com Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-14qdev: Remove hex8/32/64 property typesPaolo Bonzini
Replace them with uint8/32/64. Reviewed-by: Igor Mammedov <imammedo@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-02-11exec: Make ldl_*_phys input an AddressSpaceEdgar E. Iglesias
Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-01-14Merge remote branch 'luiz/queue/qmp' into qmpqEdgar E. Iglesias
* luiz/queue/qmp: migration: qmp_migrate(): keep working after syntax error qerror: Remove assert_no_error() qemu-option: Remove qemu_opts_create_nofail target-i386: Remove assert_no_error usage hw: Remove assert_no_error usages qdev: Delete dead code error: Add error_abort monitor: add object-add (QMP) and object_add (HMP) command monitor: add object-del (QMP) and object_del (HMP) command qom: catch errors in object_property_add_child qom: fix leak for objects created with -object rng: initialize file descriptor to -1 qemu-monitor: HMP cpu-add wrapper vl: add missing transition debug->finish_migrate Message-Id: 1389045795-18706-1-git-send-email-lcapitulino@redhat.com Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
2014-01-06hw: Remove assert_no_error usagesPeter Crosthwaite
Replace assert_no_error() usages with the error_abort system. &error_abort is passed into API calls to signal to the Error sub-system that any errors are fatal. Removes need for caller assertions. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2013-12-24hw: cannot_instantiate_with_device_add_yet due to pointer propsMarkus Armbruster
Pointer properties can be set only by code, not by device_add. A device with a pointer property can work with device_add only when the property may remain null. This is the case for property "interrupt_vector" of device "etraxfs,pic". Add a comment there. Set cannot_instantiate_with_device_add_yet for the other devices with pointer properties, with a comment explaining why. Juha Riihimäki and Peter Maydell deserve my thanks for making "pointer property must not remain null" blatantly obvious in the OMAP devices. Only device "smbus-eeprom" is actually changed. The others are all sysbus devices, which get cannot_instantiate_with_device_add_yet set in their abstract base's class init function. Setting it again in their class init function is technically redundant, but serves as insurance for when sysbus devices become available with device_add, and as documentation. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@gmail.com> (for ETRAX) Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-12-23sysbus: Set cannot_instantiate_with_device_add_yetMarkus Armbruster
device_add plugs devices into suitable bus. For "real" buses, that actually connects the device. For sysbus, the connections need to be made separately, and device_add can't do that. The device would be left unconnected, and could not possibly work. Quite a few, but not all sysbus devices already set cannot_instantiate_with_device_add_yet in their class init function. Set it in their abstract base's class init function sysbus_device_class_init(), and remove the now redundant assignments from device class init functions. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-12-23qdev: Replace no_user by cannot_instantiate_with_device_add_yetMarkus Armbruster
In an ideal world, machines can be built by wiring devices together with configuration, not code. Unfortunately, that's not the world we live in right now. We still have quite a few devices that need to be wired up by code. If you try to device_add such a device, it'll fail in sometimes mysterious ways. If you're lucky, you get an unmysterious immediate crash. To protect users from such badness, DeviceClass member no_user used to make device models unavailable with -device / device_add, but that regressed in commit 18b6dad. The device model is still omitted from help, but is available anyway. Attempts to fix the regression have been rejected with the argument that the purpose of no_user isn't clear, and it's prone to misuse. This commit clarifies no_user's purpose. Anthony suggested to rename it cannot_instantiate_with_device_add_yet_due_to_internal_bugs, which I shorten somewhat to keep checkpatch happy. While there, make it bool. Every use of cannot_instantiate_with_device_add_yet gets a FIXME comment asking for rationale. The next few commits will clean them all up, either by providing a rationale, or by getting rid of the use. With that done, the regression fix is hopefully acceptable. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com> Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-08-30qom: Pass available size to object_initialize()Andreas Färber
To be passed on to object_initialize_with_type(). Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> (virtio-ccw) Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-08-22aio / timers: Switch entire codebase to the new timer APIAlex Bligh
This is an autogenerated patch using scripts/switch-timer-api. Switch the entire code base to using the new timer API. Note this patch may introduce some line length issues. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22aio / timers: Untangle include filesAlex Bligh
include/qemu/timer.h has no need to include main-loop.h and doing so causes an issue for the next patch. Unfortunately various files assume including timers.h will pull in main-loop.h. Untangle this mess. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-29sun4m_iommu: QOM cast cleanupAndreas Färber
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-29sparc32_dma: QOM cast cleanupAndreas Färber
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-29pxa2xx_dma: QOM cast cleanupAndreas Färber
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-29puv3_dma: QOM cast cleanupAndreas Färber
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-29pl080: QOM'ify pl080 and pl081Andreas Färber
Let pl081 inherit from pl080 and replace triple SysBus initfn with two instance_inits. Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-29pl080: Rename pl080_state to PL080StateAndreas Färber
Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-07-15hw/dma/omap_dma: Fix bugs with DMA requests above 32Peter Maydell
The drqbmp field of struct soc_dma_s is a uint64_t; however several places in the code attempt to set bits in it using "(1 << drq)", which will fail if drq is large enough that the 1 bit gets shifted off the top of a 32 bit integer. Change these to "(1ULL << drq)" so that the promotion to 64 bit happens before the shift rather than afterwards. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Message-id: 1372423919-5669-1-git-send-email-peter.maydell@linaro.org
2013-07-04hw/d*: pass owner to memory_region_init* functionsPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-04piolist: add owner argument to initialization functions and pass devicesPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-04memory: add owner argument to initialization functionsPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-04i82374: replace register_ioport*Jan Kiszka
Convert over to memory regions to obsolete register_ioport*. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-20dma: eliminate DMAContextPaolo Bonzini
The DMAContext is a simple pointer to an AddressSpace that is now always already available. Make everyone hold the address space directly, and clean up the DMA API to use the AddressSpace directly. Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-06-15Merge branch 'realize-isa.v2' of git://github.com/afaerber/qemu-cpuBlue Swirl
* 'realize-isa.v2' of git://github.com/afaerber/qemu-cpu: qdev: Drop FROM_QBUS() macro isa: QOM'ify ISADevice isa: QOM'ify ISABus i8259: Convert PICCommonState to use QOM realizefn kvm/i8259: QOM'ify some more i8259: QOM'ify some more i8254: Convert PITCommonState to QOM realizefn kvm/i8254: QOM'ify some more i8254: QOM'ify some more isa: Use realizefn for ISADevice cs4231a: QOM'ify some more gus: QOM'ify some more
2013-06-10xilinx_axidma: Do not set DMA .notify to NULL after notifyWendy Liang
If a stream notify function is not ready, it may re-populate the notify call- back to indicate it should be re-polled later. This break in this usage, as immediately following the notify() call, .notify is set to NULL. reverse the ordering of the notify call and NULL assignment accordingly. [PC: Reworked commit message] Signed-off-by: Wendy Liang <jliang@xilinx.com> Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2013-06-07isa: Use realizefn for ISADeviceAndreas Färber
Drop ISADeviceClass::init and the resulting no-op initfn and let children implement their own realizefn. Adapt error handling. Split off an instance_init where sensible. Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-05-20Rename hexdump to avoid FreeBSD libutil conflictEd Maste
On FreeBSD libutil is used for openpty(), but it also provides a hexdump() which conflicts with QEMU's. Signed-off-by: Ed Maste <emaste@freebsd.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Message-id: 1368718348-15199-1-git-send-email-emaste@freebsd.org Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-29i82374: QOM'ifyAndreas Färber
Introduce type constant and cast macro to obsolete DO_UPCAST(). Prepares for ISA realizefn. Signed-off-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Andreas Färber <afaerber@suse.de> Message-id: 1367093935-29091-5-git-send-email-afaerber@suse.de Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-20qdev: Drop taddr propertiesPeter Maydell
Drop all the infrastructure for taddr properties (ie ones which are 'hwaddr' sized). These are now unused, and any further desired use would be rather questionable since device properties shouldn't generally depend on a type that is conceptually variable based on the target CPU. 32 or 64 bit integer properties should be used instead as appropriate for the specific device. Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-04-19Remove unneeded type castsStefan Weil
cpu_physical_memory_read, cpu_physical_memory_write take any pointer as 2nd argument without needing a type cast. Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-04-16stream: Remove app argument hackPeter Crosthwaite
The uint32_t *app argument doesn't exist in real hardware. It was a hack in xilinx_axidma/enet to fake the (secondary) control stream connection. Removed the argument and added the second stream to axienet/dma. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2013-04-16xilinx_axienet/dma: Implement rx path flow controlPeter Crosthwaite
Implement flow control for the RX data path from xilinx_axienet->xilinx_axidma. On short return from axidma, then ethernet sets up the notify callback to resume transfer from where it left off. This also allows the ethernet to track whether there is an in progress transaction and return false from ethernet can_receive() as appropriate. If the DMA backs up or is disabled it waits for enablement. When the rx stream IO region is touched, the can_push() notify function is called if set. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>
2013-04-16stream: Add flow control APIPeter Crosthwaite
Add basic flow control to stream. A stream slave may return short, indicating that it is not capable of accepting any more data at the present time. Polling or a callback can be used via the can_push() function to determine when the slave can receive again. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@gmail.com>