@@ -1,4 +1,4 @@
#
# Makefile for kernel slimbus framework.
#
-obj-$(CONFIG_SLIMBUS) += slim-core.o
+obj-$(CONFIG_SLIMBUS) += slim-core.o slim-messaging.o
@@ -17,6 +17,7 @@
#include <linux/completion.h>
#include <linux/idr.h>
#include <linux/pm_runtime.h>
+#include <linux/dma-mapping.h>
#include <linux/slimbus.h>
#include <linux/of.h>
@@ -454,7 +455,37 @@ int slim_register_controller(struct slim_controller *ctrl)
ctrl->min_cg = SLIM_MIN_CLK_GEAR;
if (!ctrl->max_cg)
ctrl->max_cg = SLIM_MAX_CLK_GEAR;
+
mutex_init(&ctrl->m_ctrl);
+ spin_lock_init(&ctrl->tx.lock);
+ spin_lock_init(&ctrl->rx.lock);
+
+ ctrl->pending_wr = kcalloc((ctrl->tx.n - 1),
+ sizeof(struct slim_pending),
+ GFP_KERNEL);
+ if (!ctrl->pending_wr) {
+ ret = -ENOMEM;
+ goto wr_alloc_failed;
+ }
+
+ sema_init(&ctrl->tx_sem, (ctrl->tx.n - 1));
+
+ ctrl->tx.base = dma_alloc_coherent(ctrl->dev.parent,
+ (ctrl->tx.sl_sz * ctrl->tx.n),
+ &ctrl->tx.phy, GFP_KERNEL);
+ if (!ctrl->tx.base) {
+ ret = -ENOMEM;
+ goto tx_alloc_failed;
+ }
+
+ ctrl->rx.base = dma_alloc_coherent(ctrl->dev.parent,
+ (ctrl->rx.sl_sz * ctrl->rx.n),
+ &ctrl->rx.phy, GFP_KERNEL);
+ if (!ctrl->rx.base) {
+ ret = -ENOMEM;
+ goto rx_alloc_failed;
+ }
+
ret = device_register(&ctrl->dev);
if (ret)
goto out_list;
@@ -472,10 +503,19 @@ int slim_register_controller(struct slim_controller *ctrl)
err_workq_failed:
device_unregister(&ctrl->dev);
+ dma_free_coherent(ctrl->dev.parent, (ctrl->rx.sl_sz * ctrl->rx.n),
+ ctrl->rx.base, ctrl->rx.phy);
+rx_alloc_failed:
+ dma_free_coherent(ctrl->dev.parent, (ctrl->tx.sl_sz * ctrl->tx.n),
+ ctrl->tx.base, ctrl->tx.phy);
+tx_alloc_failed:
+ kfree(ctrl->pending_wr);
+wr_alloc_failed:
out_list:
mutex_lock(&slim_lock);
idr_remove(&ctrl_idr, ctrl->nr);
mutex_unlock(&slim_lock);
+ dev_err(&ctrl->dev, "slimbus controller registration failed:%d", ret);
return ret;
}
EXPORT_SYMBOL_GPL(slim_register_controller);
@@ -527,6 +567,10 @@ int slim_del_controller(struct slim_controller *ctrl)
wait_for_completion(&ctrl->dev_released);
list_del(&ctrl->list);
destroy_workqueue(ctrl->wq);
+ dma_free_coherent(ctrl->dev.parent, (ctrl->rx.sl_sz * ctrl->rx.n),
+ ctrl->rx.base, ctrl->rx.phy);
+ dma_free_coherent(ctrl->dev.parent, (ctrl->tx.sl_sz * ctrl->tx.n),
+ ctrl->tx.base, ctrl->tx.phy);
/* free bus id */
mutex_lock(&slim_lock);
idr_remove(&ctrl_idr, ctrl->nr);
new file mode 100644
@@ -0,0 +1,378 @@
+/* Copyright (c) 2011-2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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.
+ */
+#include <linux/slab.h>
+#include <linux/slimbus.h>
+
+/**
+ * slim_msg_response: Deliver Message response received from a device to the
+ * framework.
+ * @ctrl: Controller handle
+ * @reply: Reply received from the device
+ * @len: Length of the reply
+ * @tid: Transaction ID received with which framework can associate reply.
+ * Called by controller to inform framework about the response received.
+ * This helps in making the API asynchronous, and controller-driver doesn't need
+ * to manage 1 more table other than the one managed by framework mapping TID
+ * with buffers
+ */
+void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 len)
+{
+ struct slim_val_inf *msg;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctrl->txn_lock, flags);
+ msg = ctrl->tid_tbl[tid];
+ if (msg == NULL || msg->rbuf == NULL) {
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+ dev_err(&ctrl->dev, "Got response to invalid TID:%d, len:%d\n",
+ tid, len);
+ return;
+ }
+ memcpy(msg->rbuf, reply, len);
+ ctrl->tid_tbl[tid] = NULL;
+ if (msg->comp_cb)
+ msg->comp_cb(msg->ctx, 0);
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+}
+EXPORT_SYMBOL_GPL(slim_msg_response);
+
+struct slim_cb_data {
+ struct completion *comp;
+ int ret;
+};
+
+static void slim_sync_default_cb(void *ctx, int err)
+{
+ struct slim_cb_data *cbd = ctx;
+
+ cbd->ret = err;
+ complete(cbd->comp);
+}
+
+int slim_processtxn(struct slim_controller *ctrl,
+ struct slim_msg_txn *txn)
+{
+ int ret, i = 0;
+ unsigned long flags;
+ u8 *buf;
+ bool async = false;
+ struct slim_cb_data cbd;
+ DECLARE_COMPLETION_ONSTACK(done);
+ bool need_tid = slim_tid_txn(txn->mt, txn->mc);
+
+ if (!txn->msg->comp_cb) {
+ txn->msg->comp_cb = slim_sync_default_cb;
+ cbd.comp = &done;
+ txn->msg->ctx = &cbd;
+ } else {
+ async = true;
+ }
+
+ buf = slim_get_tx(ctrl, txn, need_tid, async);
+ if (!buf)
+ return -ENOMEM;
+
+ if (need_tid) {
+ spin_lock_irqsave(&ctrl->txn_lock, flags);
+ for (i = 0; i < ctrl->last_tid; i++) {
+ if (ctrl->tid_tbl[i] == NULL)
+ break;
+ }
+ if (i >= ctrl->last_tid) {
+ if (ctrl->last_tid == (SLIM_MAX_TIDS - 1)) {
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+ return -ENOMEM;
+ }
+ ctrl->last_tid++;
+ }
+ ctrl->tid_tbl[i] = txn->msg;
+ txn->tid = i;
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+ }
+
+ ret = ctrl->xfer_msg(ctrl, txn, buf);
+
+ if (!ret && !async) { /* sync transaction */
+ /* Fine-tune calculation after bandwidth management */
+ unsigned long ms = txn->rl + 100;
+
+ ret = wait_for_completion_timeout(&done,
+ msecs_to_jiffies(ms));
+ if (!ret)
+ slim_return_tx(ctrl, -ETIMEDOUT);
+
+ ret = cbd.ret;
+ }
+
+ if (ret && need_tid) {
+ spin_lock_irqsave(&ctrl->txn_lock, flags);
+ /* Invalidate the transaction */
+ ctrl->tid_tbl[txn->tid] = NULL;
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+ }
+ if (ret)
+ dev_err(&ctrl->dev, "Tx:MT:0x%x, MC:0x%x, LA:0x%x failed:%d\n",
+ txn->mt, txn->mc, txn->la, ret);
+ if (!async) {
+ txn->msg->comp_cb = NULL;
+ txn->msg->ctx = NULL;
+ }
+ return ret;
+}
+EXPORT_SYMBOL_GPL(slim_processtxn);
+
+static int slim_val_inf_sanity(struct slim_controller *ctrl,
+ struct slim_val_inf *msg, u8 mc)
+{
+ if (!msg || msg->num_bytes > 16 ||
+ (msg->start_offset + msg->num_bytes) > 0xC00)
+ goto reterr;
+ switch (mc) {
+ case SLIM_MSG_MC_REQUEST_VALUE:
+ case SLIM_MSG_MC_REQUEST_INFORMATION:
+ if (msg->rbuf != NULL)
+ return 0;
+ break;
+ case SLIM_MSG_MC_CHANGE_VALUE:
+ case SLIM_MSG_MC_CLEAR_INFORMATION:
+ if (msg->wbuf != NULL)
+ return 0;
+ break;
+ case SLIM_MSG_MC_REQUEST_CHANGE_VALUE:
+ case SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION:
+ if (msg->rbuf != NULL && msg->wbuf != NULL)
+ return 0;
+ break;
+ default:
+ break;
+ }
+reterr:
+ dev_err(&ctrl->dev, "Sanity check failed:msg:offset:0x%x, mc:%d\n",
+ msg->start_offset, mc);
+ return -EINVAL;
+}
+
+static u16 slim_slicecodefromsize(u16 req)
+{
+ static const u8 codetosize[8] = {1, 2, 3, 4, 6, 8, 12, 16};
+
+ if (req >= ARRAY_SIZE(codetosize))
+ return 0;
+ else
+ return codetosize[req];
+}
+
+static u16 slim_slicesize(int code)
+{
+ static const u8 sizetocode[16] = {
+ 0, 1, 2, 3, 3, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7
+ };
+
+ clamp(code, 1, (int)ARRAY_SIZE(sizetocode));
+ return sizetocode[code - 1];
+}
+
+int slim_xfer_msg(struct slim_controller *ctrl,
+ struct slim_device *sbdev, struct slim_val_inf *msg,
+ u8 mc)
+{
+ DEFINE_SLIM_LDEST_TXN(txn_stack, mc, 6, sbdev->laddr, msg);
+ struct slim_msg_txn *txn = &txn_stack;
+ int ret;
+ u16 sl, cur;
+
+ ret = slim_val_inf_sanity(ctrl, msg, mc);
+ if (ret)
+ return ret;
+
+ sl = slim_slicesize(msg->num_bytes);
+ dev_dbg(&ctrl->dev, "SB xfer msg:os:%x, len:%d, MC:%x, sl:%x\n",
+ msg->start_offset, msg->num_bytes, mc, sl);
+
+ cur = slim_slicecodefromsize(sl);
+ txn->ec = ((sl | (1 << 3)) | ((msg->start_offset & 0xFFF) << 4));
+
+ if (mc == SLIM_MSG_MC_REQUEST_CHANGE_VALUE ||
+ mc == SLIM_MSG_MC_CHANGE_VALUE ||
+ mc == SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION ||
+ mc == SLIM_MSG_MC_CLEAR_INFORMATION)
+ txn->rl += msg->num_bytes;
+ if (slim_tid_txn(txn->mt, txn->mc))
+ txn->rl++;
+
+ return slim_processtxn(ctrl, txn);
+}
+EXPORT_SYMBOL_GPL(slim_xfer_msg);
+
+/* Message APIs Unicast message APIs used by slimbus slave drivers */
+
+/*
+ * Message API access routines.
+ * @sb: client handle requesting elemental message reads, writes.
+ * @msg: Input structure for start-offset, number of bytes to read.
+ * context: can sleep
+ * Returns:
+ * -EINVAL: Invalid parameters
+ * -ETIMEDOUT: If transmission of this message timed out (e.g. due to bus lines
+ * not being clocked or driven by controller)
+ * -ENOTCONN: If the transmitted message was not ACKed by destination device.
+ */
+int slim_request_val_element(struct slim_device *sb,
+ struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg, SLIM_MSG_MC_REQUEST_VALUE);
+}
+EXPORT_SYMBOL_GPL(slim_request_val_element);
+
+int slim_request_inf_element(struct slim_device *sb,
+ struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg, SLIM_MSG_MC_REQUEST_INFORMATION);
+}
+EXPORT_SYMBOL_GPL(slim_request_inf_element);
+
+int slim_change_val_element(struct slim_device *sb, struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg, SLIM_MSG_MC_CHANGE_VALUE);
+}
+EXPORT_SYMBOL_GPL(slim_change_val_element);
+
+int slim_clear_inf_element(struct slim_device *sb, struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg, SLIM_MSG_MC_CLEAR_INFORMATION);
+}
+EXPORT_SYMBOL_GPL(slim_clear_inf_element);
+
+int slim_request_change_val_element(struct slim_device *sb,
+ struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg, SLIM_MSG_MC_REQUEST_CHANGE_VALUE);
+}
+EXPORT_SYMBOL_GPL(slim_request_change_val_element);
+
+int slim_request_clear_inf_element(struct slim_device *sb,
+ struct slim_val_inf *msg)
+{
+ struct slim_controller *ctrl = sb->ctrl;
+
+ if (!ctrl)
+ return -EINVAL;
+ return slim_xfer_msg(ctrl, sb, msg,
+ SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION);
+}
+EXPORT_SYMBOL_GPL(slim_request_clear_inf_element);
+
+/* Functions to get/return TX, RX buffers for messaging. */
+
+void *slim_get_rx(struct slim_controller *ctrl)
+{
+ unsigned long flags;
+ int idx;
+
+ spin_lock_irqsave(&ctrl->rx.lock, flags);
+ if ((ctrl->rx.tail + 1) % ctrl->rx.n == ctrl->rx.head) {
+ spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+ dev_err(&ctrl->dev, "RX QUEUE full!");
+ return NULL;
+ }
+ idx = ctrl->rx.tail;
+ ctrl->rx.tail = (ctrl->rx.tail + 1) % ctrl->rx.n;
+ spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+ return ctrl->rx.base + (idx * ctrl->rx.sl_sz);
+}
+EXPORT_SYMBOL_GPL(slim_get_rx);
+
+int slim_return_rx(struct slim_controller *ctrl, void *buf)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ctrl->rx.lock, flags);
+ if (ctrl->rx.tail == ctrl->rx.head) {
+ spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+ return -ENODATA;
+ }
+ memcpy(buf, ctrl->rx.base + (ctrl->rx.head * ctrl->rx.sl_sz),
+ ctrl->rx.sl_sz);
+ ctrl->rx.head = (ctrl->rx.head + 1) % ctrl->rx.n;
+ spin_unlock_irqrestore(&ctrl->rx.lock, flags);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(slim_return_rx);
+
+void slim_return_tx(struct slim_controller *ctrl, int err)
+{
+ unsigned long flags;
+ int idx;
+ struct slim_pending cur;
+
+ spin_lock_irqsave(&ctrl->tx.lock, flags);
+ idx = ctrl->tx.head;
+ ctrl->tx.head = (ctrl->tx.head + 1) % ctrl->tx.n;
+ cur = ctrl->pending_wr[idx];
+ ctrl->pending_wr[idx].cb = NULL;
+ spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+ if (!cur.cb)
+ dev_err(&ctrl->dev, "NULL Transaction or completion");
+ else
+ cur.cb(cur.ctx, err);
+ up(&ctrl->tx_sem);
+}
+EXPORT_SYMBOL_GPL(slim_return_tx);
+
+void *slim_get_tx(struct slim_controller *ctrl, struct slim_msg_txn *txn,
+ bool need_tid, bool async)
+{
+ unsigned long flags;
+ int ret, idx;
+
+ ret = down_interruptible(&ctrl->tx_sem);
+ if (ret < 0) {
+ dev_err(&ctrl->dev, "TX semaphore down returned:%d", ret);
+ return NULL;
+ }
+ spin_lock_irqsave(&ctrl->tx.lock, flags);
+ if (((ctrl->tx.head + 1) % ctrl->tx.n) == ctrl->tx.tail) {
+ spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+ dev_err(&ctrl->dev, "controller TX buf unavailable");
+ up(&ctrl->tx_sem);
+ return NULL;
+ }
+ idx = ctrl->tx.tail;
+ ctrl->tx.tail = (ctrl->tx.tail + 1) % ctrl->tx.n;
+ spin_unlock_irqrestore(&ctrl->tx.lock, flags);
+ ctrl->pending_wr[idx].cb = txn->msg->comp_cb;
+ ctrl->pending_wr[idx].ctx = txn->msg->ctx;
+ ctrl->pending_wr[idx].need_tid = need_tid;
+ ctrl->pending_wr[idx].async = async;
+ return ctrl->tx.base + (idx * ctrl->tx.sl_sz);
+}
+EXPORT_SYMBOL_GPL(slim_get_tx);
@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/device.h>
#include <linux/mutex.h>
+#include <linux/semaphore.h>
#include <linux/mod_devicetable.h>
/**
@@ -34,6 +35,9 @@ extern struct bus_type slimbus_type;
#define SLIM_FRM_SLOTS_PER_SUPERFRAME 16
#define SLIM_GDE_SLOTS_PER_SUPERFRAME 2
+/* MAX in-flight transactions neededing transaction ID (8-bit, per spec) */
+#define SLIM_MAX_TIDS 256
+
struct slim_controller;
struct slim_device;
@@ -100,12 +104,117 @@ struct slim_addrt {
#define SLIM_MSG_MC_ASSIGN_LOGICAL_ADDRESS 0x2
#define SLIM_MSG_MC_REPORT_ABSENT 0xF
+/* Information Element management messages */
+#define SLIM_MSG_MC_REQUEST_INFORMATION 0x20
+#define SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION 0x21
+#define SLIM_MSG_MC_REPLY_INFORMATION 0x24
+#define SLIM_MSG_MC_CLEAR_INFORMATION 0x28
+#define SLIM_MSG_MC_REPORT_INFORMATION 0x29
+
+/* Value Element management messages */
+#define SLIM_MSG_MC_REQUEST_VALUE 0x60
+#define SLIM_MSG_MC_REQUEST_CHANGE_VALUE 0x61
+#define SLIM_MSG_MC_REPLY_VALUE 0x64
+#define SLIM_MSG_MC_CHANGE_VALUE 0x68
+
/* Destination type Values */
#define SLIM_MSG_DEST_LOGICALADDR 0
#define SLIM_MSG_DEST_ENUMADDR 1
#define SLIM_MSG_DEST_BROADCAST 3
/**
+ * struct slim_val_inf: Slimbus value or information element
+ * @start_offset: Specifies starting offset in information/value element map
+ * @num_bytes: upto 16. This ensures that the message will fit the slicesize
+ * per slimbus spec
+ * @comp_cb: Callback if this read/write is asynchronous
+ * @ctx: Argument for comp_cb
+ */
+struct slim_val_inf {
+ u16 start_offset;
+ u8 num_bytes;
+ u8 *rbuf;
+ const u8 *wbuf;
+ void (*comp_cb)(void *ctx, int err);
+ void *ctx;
+};
+
+/**
+ * struct slim_msg_txn: Message to be sent by the controller.
+ * This structure has packet header, payload and buffer to be filled (if any)
+ * @rl: Header field. remaining length.
+ * @mt: Header field. Message type.
+ * @mc: Header field. LSB is message code for type mt.
+ * @dt: Header field. Destination type.
+ * @ec: Element code. Used for elemental access APIs.
+ * @len: Length of payload. (excludes ec)
+ * @tid: Transaction ID. Used for messages expecting response.
+ * (relevant for message-codes involving read operation)
+ * @la: Logical address of the device this message is going to.
+ * (Not used when destination type is broadcast.)
+ * @msg: Elemental access message to be read/written
+ */
+struct slim_msg_txn {
+ u8 rl;
+ u8 mt;
+ u8 mc;
+ u8 dt;
+ u16 ec;
+ u8 tid;
+ u8 la;
+ struct slim_val_inf *msg;
+};
+
+/* Frequently used message transaction structures */
+#define DEFINE_SLIM_LDEST_TXN(name, mc, rl, la, msg) \
+ struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_LOGICALADDR, 0,\
+ 0, la, msg, }
+
+#define DEFINE_SLIM_BCAST_TXN(name, mc, rl, la, msg) \
+ struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_BROADCAST, 0,\
+ 0, la, msg, }
+
+#define DEFINE_SLIM_EDEST_TXN(name, mc, rl, la, msg) \
+ struct slim_msg_txn name = { rl, 0, mc, SLIM_MSG_DEST_ENUMADDR, 0,\
+ 0, la, msg, }
+
+/**
+ * struct slim_ctrl_buf: circular buffer used by contoller for TX, RX
+ * @base: virtual base address for this buffer
+ * @phy: physical address for this buffer (this is useful if controller can
+ * DMA the buffers for TX and RX to/from controller hardware
+ * @lock: lock protecting head and tail
+ * @head: index where buffer is returned back
+ * @tail: index from where buffer is consumed
+ * @sl_sz: byte-size of each slot in this buffer
+ * @n: number of elements in this circular ring, note that this needs to be
+ * 1 more than actual buffers to allow for one open slot
+ */
+struct slim_ctrl_buf {
+ void *base;
+ phys_addr_t phy;
+ spinlock_t lock;
+ int head;
+ int tail;
+ int sl_sz;
+ int n;
+};
+
+/**
+ * struct slim_pending: context of pending transfers
+ * @cb: callback for this transfer
+ * @ctx: contex for the callback function
+ * @need_tid: True if this transfer need Transaction ID
+ * @async: True if this is asynchronous transfer
+ */
+struct slim_pending {
+ void (*cb)(void *ctx, int err);
+ void *ctx;
+ bool need_tid;
+ bool async;
+};
+
+/**
* struct slim_controller: Controls every instance of SLIMbus
* (similar to 'master' on SPI)
* 'Manager device' is responsible for device management, bandwidth
@@ -140,6 +249,16 @@ struct slim_addrt {
* @num_dev: Number of active slimbus slaves on this bus
* @devs: List of devices on this controller
* @wq: Workqueue per controller used to notify devices when they report present
+ * @tid_tbl: Table of transactions having transaction ID
+ * @txn_lock: Lock to protect table of transactions
+ * @rx: RX buffers used by controller to receive messages. Ctrl may receive more
+ * than 1 message (e.g. multiple report-present messages or messages from
+ * multiple slaves).
+ * @tx: TX buffers used by controller to transmit messages. Ctrl may have
+ * ability to send/queue multiple messages to HW at once.
+ * @pending_wr: Pending write transactions to be acknowledged by controller
+ * @tx_sem: Semaphore for available TX buffers for this controller
+ * @last_tid: Last used entry for TID transactions
* @dev_released: completion used to signal when sysfs has released this
* controller so that it can be deleted during shutdown
* @xfer_msg: Transfer a message on this controller (this can be a broadcast
@@ -166,7 +285,16 @@ struct slim_controller {
u8 num_dev;
struct list_head devs;
struct workqueue_struct *wq;
+ struct slim_val_inf *tid_tbl[SLIM_MAX_TIDS];
+ u8 last_tid;
+ spinlock_t txn_lock;
+ struct slim_ctrl_buf tx;
+ struct slim_ctrl_buf rx;
+ struct slim_pending *pending_wr;
+ struct semaphore tx_sem;
struct completion dev_released;
+ int (*xfer_msg)(struct slim_controller *ctrl,
+ struct slim_msg_txn *tx, void *buf);
int (*set_laddr)(struct slim_controller *ctrl,
struct slim_eaddr *ea, u8 laddr);
int (*get_laddr)(struct slim_controller *ctrl,
@@ -386,4 +514,102 @@ static inline void slim_set_clientdata(struct slim_device *dev, void *data)
dev_set_drvdata(&dev->dev, data);
}
+/* Message APIs Unicast message APIs used by slimbus slave drivers */
+
+/**
+ * Message API access routines for value elements.
+ * @sb: client handle requesting elemental message reads, writes.
+ * @msg: Input structure for start-offset, number of bytes to read.
+ * context: can sleep
+ * Returns:
+ * -EINVAL: Invalid parameters
+ * -ETIMEDOUT: If transmission of this message timed out (e.g. due to bus lines
+ * not being clocked or driven by controller)
+ * -ENOTCONN: If the transmitted message was not ACKed by destination device.
+ */
+int slim_request_val_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+int slim_change_val_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+int slim_request_change_val_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+
+
+/**
+ * Message API access routines for information elements.
+ * @sb: client handle requesting elemental message reads, writes.
+ * @msg: Input structure for start-offset, number of bytes to read
+ * wbuf will contain information element(s) bit masks to be cleared.
+ * rbuf will return what the information element value was
+ */
+
+int slim_request_inf_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+int slim_clear_inf_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+int slim_request_clear_inf_element(struct slim_device *sb,
+ struct slim_val_inf *msg);
+
+/**
+ * slim_msg_response: Deliver Message response received from a device to the
+ * framework.
+ * @ctrl: Controller handle
+ * @reply: Reply received from the device
+ * @len: Length of the reply
+ * @tid: Transaction ID received with which framework can associate reply.
+ * Called by controller to inform framework about the response received.
+ * This helps in making the API asynchronous, and controller-driver doesn't need
+ * to manage 1 more table other than the one managed by framework mapping TID
+ * with buffers
+ */
+void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid,
+ u8 len);
+
+/**
+ * slim_processtxn: Process a slimbus-messaging transaction
+ * @ctrl: Controller handle
+ * @txn: Transaction to be sent over SLIMbus
+ * Called by controller to transmit messaging transactions not dealing with
+ * Interface/Value elements. (e.g. transmittting a message to assign logical
+ * address to a slave device
+ * Returns:
+ * -ETIMEDOUT: If transmission of this message timed out (e.g. due to bus lines
+ * not being clocked or driven by controller)
+ * -ENOTCONN: If the transmitted message was not ACKed by destination device.
+ */
+int slim_processtxn(struct slim_controller *ctrl, struct slim_msg_txn *txn);
+
+/**
+ * Functions to get/put TX, RX buffers for messaging.
+ * @ctrl: Controller handle
+ * These functions are called by controller to process the TX/RX buffers.
+ * TX buffer is requested by controller when it's filled-in and sent to the
+ * HW. When HW has finished processing this buffer, controller should return it
+ * back to the pool.
+ * RX buffer is requested by controller when data is received from HW, but is
+ * not processed (e.g. 'report-present message was sent by HW in ISR and SW
+ * needs more time to process the buffer to assign Logical Address)
+ * RX buffer is returned back to the pool when associated RX action
+ * is taken (e.g. Received message is decoded and client's
+ * response buffer is filled in.)
+ */
+void *slim_get_rx(struct slim_controller *ctrl);
+
+int slim_return_rx(struct slim_controller *ctrl, void *buf);
+
+void *slim_get_tx(struct slim_controller *ctrl, struct slim_msg_txn *txn,
+ bool need_tid, bool async);
+
+void slim_return_tx(struct slim_controller *ctrl, int err);
+
+static inline bool slim_tid_txn(u8 mt, u8 mc)
+{
+ return (mt == SLIM_MSG_MT_CORE &&
+ (mc == SLIM_MSG_MC_REQUEST_INFORMATION ||
+ mc == SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION ||
+ mc == SLIM_MSG_MC_REQUEST_VALUE ||
+ mc == SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION));
+}
+/* end of message apis */
+
#endif /* _LINUX_SLIMBUS_H */