[PATCH 6/7] slimbus: messaging: add slim_prepare_txn() helper function

From: Srinivas Kandagatla
Date: Wed May 16 2018 - 07:06:50 EST


This patch adds slim_prepare_txn() to allow controllers to prepare
controller specific transaction. If not each controllers will duplicate
the same code from core.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/slimbus/messaging.c | 89 ++++++++++++++++++++++++++++++---------------
drivers/slimbus/qcom-ctrl.c | 7 +++-
drivers/slimbus/slimbus.h | 2 +
3 files changed, 68 insertions(+), 30 deletions(-)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index 1c57b631031a..fd0788019357 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -55,6 +55,50 @@ void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 len)
}
EXPORT_SYMBOL_GPL(slim_msg_response);

+/**
+ * slim_prepare_txn() - Prepare a transaction
+ *
+ * @ctrl: Controller handle
+ * @txn: transaction to be prepared
+ * @done: completion for transaction
+ * @need_tid: flag to indicate if tid is required for this txn
+ *
+ * Called by controller to prepare a transaction
+ *
+ * Return: zero on success and error code on failures.
+ */
+int slim_prepare_txn(struct slim_controller *ctrl, struct slim_msg_txn *txn,
+ struct completion *done, bool need_tid)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ spin_lock_irqsave(&ctrl->txn_lock, flags);
+
+ if (need_tid) {
+ ret = idr_alloc(&ctrl->tid_idr, txn, 0, SLIM_MAX_TIDS,
+ GFP_ATOMIC);
+ if (ret < 0) {
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+ return ret;
+ }
+ txn->tid = ret;
+ txn->need_tid = true;
+ } else {
+ txn->need_tid = false;
+ }
+
+ if (!txn->msg->comp)
+ txn->comp = done;
+ else
+ txn->comp = txn->msg->comp;
+
+ spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(slim_prepare_txn);
+
/**
* slim_do_transfer() - Process a SLIMbus-messaging transaction
*
@@ -70,10 +114,9 @@ EXPORT_SYMBOL_GPL(slim_msg_response);
*/
int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
{
- DECLARE_COMPLETION_ONSTACK(done);
- bool need_tid = false, clk_pause_msg = false;
+ bool clk_pause_msg = false;
unsigned long flags;
- int ret, tid, timeout;
+ int ret, timeout;

/*
* do not vote for runtime-PM if the transactions are part of clock
@@ -94,28 +137,8 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
}
}

- need_tid = slim_tid_txn(txn->mt, txn->mc);
-
- if (need_tid) {
- spin_lock_irqsave(&ctrl->txn_lock, flags);
- tid = idr_alloc(&ctrl->tid_idr, txn, 0,
- SLIM_MAX_TIDS, GFP_ATOMIC);
- txn->tid = tid;
-
- if (!txn->msg->comp)
- txn->comp = &done;
- else
- txn->comp = txn->comp;
-
- spin_unlock_irqrestore(&ctrl->txn_lock, flags);
-
- if (tid < 0)
- return tid;
- }
-
ret = ctrl->xfer_msg(ctrl, txn);
-
- if (ret && need_tid && !txn->msg->comp) {
+ if (!ret && txn->need_tid && !txn->msg->comp) {
unsigned long ms = txn->rl + HZ;

timeout = wait_for_completion_timeout(txn->comp,
@@ -123,7 +146,7 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
if (!timeout) {
ret = -ETIMEDOUT;
spin_lock_irqsave(&ctrl->txn_lock, flags);
- idr_remove(&ctrl->tid_idr, tid);
+ idr_remove(&ctrl->tid_idr, txn->tid);
spin_unlock_irqrestore(&ctrl->txn_lock, flags);
}
}
@@ -133,13 +156,12 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
txn->mt, txn->mc, txn->la, ret);

slim_xfer_err:
- if (!clk_pause_msg && (!need_tid || ret == -ETIMEDOUT)) {
+ if (!clk_pause_msg && (!txn->need_tid || ret == -ETIMEDOUT)) {
/*
* remove runtime-pm vote if this was TX only, or
* if there was error during this transaction
*/
pm_runtime_mark_last_busy(ctrl->dev);
- pm_runtime_put_autosuspend(ctrl->dev);
}
return ret;
}
@@ -169,6 +191,7 @@ static int slim_val_inf_sanity(struct slim_controller *ctrl,
if (msg->rbuf != NULL && msg->wbuf != NULL)
return 0;
break;
+
}
reterr:
if (msg)
@@ -205,6 +228,8 @@ int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
DEFINE_SLIM_LDEST_TXN(txn_stack, mc, 6, sbdev->laddr, msg);
struct slim_msg_txn *txn = &txn_stack;
struct slim_controller *ctrl = sbdev->ctrl;
+ DECLARE_COMPLETION_ONSTACK(done);
+ bool need_tid = false;
int ret;
u16 sl;

@@ -232,10 +257,16 @@ int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
break;
}

- if (slim_tid_txn(txn->mt, txn->mc))
+ if (slim_tid_txn(txn->mt, txn->mc)) {
txn->rl++;
+ need_tid = true;
+ }

- return slim_do_transfer(ctrl, txn);
+ ret = slim_prepare_txn(ctrl, txn, &done, need_tid);
+ if (!ret)
+ return slim_do_transfer(ctrl, txn);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(slim_xfer_msg);

diff --git a/drivers/slimbus/qcom-ctrl.c b/drivers/slimbus/qcom-ctrl.c
index ffb46f915334..0783fb11c702 100644
--- a/drivers/slimbus/qcom-ctrl.c
+++ b/drivers/slimbus/qcom-ctrl.c
@@ -397,6 +397,7 @@ static int qcom_set_laddr(struct slim_controller *sctrl,
u8 instance;
u8 laddr;
} __packed p;
+ DECLARE_COMPLETION_ONSTACK(done);
struct slim_val_inf msg = {0};
DEFINE_SLIM_EDEST_TXN(txn, SLIM_MSG_MC_ASSIGN_LOGICAL_ADDRESS,
10, laddr, &msg);
@@ -410,7 +411,11 @@ static int qcom_set_laddr(struct slim_controller *sctrl,

msg.wbuf = (void *)&p;
msg.num_bytes = 7;
- ret = slim_do_transfer(&ctrl->ctrl, &txn);
+
+ ret = slim_prepare_txn(&ctrl->ctrl, &txn, &done,
+ slim_tid_txn(txn.mt, txn.mc));
+ if (!ret)
+ ret = slim_do_transfer(&ctrl->ctrl, &txn);

if (ret)
dev_err(ctrl->dev, "set LA:0x%x failed:ret:%d\n",
diff --git a/drivers/slimbus/slimbus.h b/drivers/slimbus/slimbus.h
index c0450f469e07..67e774b2b2dd 100644
--- a/drivers/slimbus/slimbus.h
+++ b/drivers/slimbus/slimbus.h
@@ -241,6 +241,8 @@ int slim_unregister_controller(struct slim_controller *ctrl);
void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 l);
int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn);
int slim_ctrl_clk_pause(struct slim_controller *ctrl, bool wakeup, u8 restart);
+int slim_prepare_txn(struct slim_controller *ctrl, struct slim_msg_txn *txn,
+ struct completion *done, bool need_tid);

static inline bool slim_tid_txn(u8 mt, u8 mc)
{
--
2.16.2