summaryrefslogtreecommitdiffstats
path: root/drivers/dma/dmaengine.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /drivers/dma/dmaengine.h
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'drivers/dma/dmaengine.h')
-rw-r--r--drivers/dma/dmaengine.h201
1 files changed, 201 insertions, 0 deletions
diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h
new file mode 100644
index 000000000..53f16d3f0
--- /dev/null
+++ b/drivers/dma/dmaengine.h
@@ -0,0 +1,201 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * The contents of this file are private to DMA engine drivers, and is not
+ * part of the API to be used by DMA engine users.
+ */
+#ifndef DMAENGINE_H
+#define DMAENGINE_H
+
+#include <linux/bug.h>
+#include <linux/dmaengine.h>
+
+/**
+ * dma_cookie_init - initialize the cookies for a DMA channel
+ * @chan: dma channel to initialize
+ */
+static inline void dma_cookie_init(struct dma_chan *chan)
+{
+ chan->cookie = DMA_MIN_COOKIE;
+ chan->completed_cookie = DMA_MIN_COOKIE;
+}
+
+/**
+ * dma_cookie_assign - assign a DMA engine cookie to the descriptor
+ * @tx: descriptor needing cookie
+ *
+ * Assign a unique non-zero per-channel cookie to the descriptor.
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline dma_cookie_t dma_cookie_assign(struct dma_async_tx_descriptor *tx)
+{
+ struct dma_chan *chan = tx->chan;
+ dma_cookie_t cookie;
+
+ cookie = chan->cookie + 1;
+ if (cookie < DMA_MIN_COOKIE)
+ cookie = DMA_MIN_COOKIE;
+ tx->cookie = chan->cookie = cookie;
+
+ return cookie;
+}
+
+/**
+ * dma_cookie_complete - complete a descriptor
+ * @tx: descriptor to complete
+ *
+ * Mark this descriptor complete by updating the channels completed
+ * cookie marker. Zero the descriptors cookie to prevent accidental
+ * repeated completions.
+ *
+ * Note: caller is expected to hold a lock to prevent concurrency.
+ */
+static inline void dma_cookie_complete(struct dma_async_tx_descriptor *tx)
+{
+ BUG_ON(tx->cookie < DMA_MIN_COOKIE);
+ tx->chan->completed_cookie = tx->cookie;
+ tx->cookie = 0;
+}
+
+/**
+ * dma_cookie_status - report cookie status
+ * @chan: dma channel
+ * @cookie: cookie we are interested in
+ * @state: dma_tx_state structure to return last/used cookies
+ *
+ * Report the status of the cookie, filling in the state structure if
+ * non-NULL. No locking is required.
+ */
+static inline enum dma_status dma_cookie_status(struct dma_chan *chan,
+ dma_cookie_t cookie, struct dma_tx_state *state)
+{
+ dma_cookie_t used, complete;
+
+ used = chan->cookie;
+ complete = chan->completed_cookie;
+ barrier();
+ if (state) {
+ state->last = complete;
+ state->used = used;
+ state->residue = 0;
+ state->in_flight_bytes = 0;
+ }
+ return dma_async_is_complete(cookie, complete, used);
+}
+
+static inline void dma_set_residue(struct dma_tx_state *state, u32 residue)
+{
+ if (state)
+ state->residue = residue;
+}
+
+static inline void dma_set_in_flight_bytes(struct dma_tx_state *state,
+ u32 in_flight_bytes)
+{
+ if (state)
+ state->in_flight_bytes = in_flight_bytes;
+}
+
+struct dmaengine_desc_callback {
+ dma_async_tx_callback callback;
+ dma_async_tx_callback_result callback_result;
+ void *callback_param;
+};
+
+/**
+ * dmaengine_desc_get_callback - get the passed in callback function
+ * @tx: tx descriptor
+ * @cb: temp struct to hold the callback info
+ *
+ * Fill the passed in cb struct with what's available in the passed in
+ * tx descriptor struct
+ * No locking is required.
+ */
+static inline void
+dmaengine_desc_get_callback(struct dma_async_tx_descriptor *tx,
+ struct dmaengine_desc_callback *cb)
+{
+ cb->callback = tx->callback;
+ cb->callback_result = tx->callback_result;
+ cb->callback_param = tx->callback_param;
+}
+
+/**
+ * dmaengine_desc_callback_invoke - call the callback function in cb struct
+ * @cb: temp struct that is holding the callback info
+ * @result: transaction result
+ *
+ * Call the callback function provided in the cb struct with the parameter
+ * in the cb struct.
+ * Locking is dependent on the driver.
+ */
+static inline void
+dmaengine_desc_callback_invoke(struct dmaengine_desc_callback *cb,
+ const struct dmaengine_result *result)
+{
+ struct dmaengine_result dummy_result = {
+ .result = DMA_TRANS_NOERROR,
+ .residue = 0
+ };
+
+ if (cb->callback_result) {
+ if (!result)
+ result = &dummy_result;
+ cb->callback_result(cb->callback_param, result);
+ } else if (cb->callback) {
+ cb->callback(cb->callback_param);
+ }
+}
+
+/**
+ * dmaengine_desc_get_callback_invoke - get the callback in tx descriptor and
+ * then immediately call the callback.
+ * @tx: dma async tx descriptor
+ * @result: transaction result
+ *
+ * Call dmaengine_desc_get_callback() and dmaengine_desc_callback_invoke()
+ * in a single function since no work is necessary in between for the driver.
+ * Locking is dependent on the driver.
+ */
+static inline void
+dmaengine_desc_get_callback_invoke(struct dma_async_tx_descriptor *tx,
+ const struct dmaengine_result *result)
+{
+ struct dmaengine_desc_callback cb;
+
+ dmaengine_desc_get_callback(tx, &cb);
+ dmaengine_desc_callback_invoke(&cb, result);
+}
+
+/**
+ * dmaengine_desc_callback_valid - verify the callback is valid in cb
+ * @cb: callback info struct
+ *
+ * Return a bool that verifies whether callback in cb is valid or not.
+ * No locking is required.
+ */
+static inline bool
+dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
+{
+ return cb->callback || cb->callback_result;
+}
+
+struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
+struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev) {
+ return dma_dev->dbg_dev_root;
+}
+#else
+struct dentry;
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev)
+{
+ return NULL;
+}
+#endif /* CONFIG_DEBUG_FS */
+
+#endif