[PATCH v3 0/8] slimbus: fixes and some helpers

[PATCH v3 0/8] slimbus: fixes and some helpers

[Srinivas Kandagatla]

Hi Greg,

Here is set of patches for slimbus, there are 6 fixes and
two helper functions.
Most of these issues were found while testing QCOM NGD SLIMBus
controller with WCD9335 codec.

Changes since v2 (https://lkml.org/lkml/2018/5/17/251)
- removed unnecessary changes in slim_prepare_txn patch

thanks,
Srini

Srinivas Kandagatla (8):
  slimbus: core: rearrange slim_eaddr structure
  slimbus: core: add need_tid flag to slim_msg_txn
  slimbus: messaging: pass correct wbuf
  slimbus: messaging: remove multiple calls to pm_runtime_mark_last_busy
  slimbus: messaging: initialize completion correctly
  slimbus: qcom: remove redundant depends in Kconfig
  slimbus: messaging: add slim_prepare_txn() helper function
  slimbus: core: add of_slim_device_get() helper

 drivers/slimbus/Kconfig     |  1 -
 drivers/slimbus/core.c      | 39 ++++++++++++++++++++
 drivers/slimbus/messaging.c | 89 ++++++++++++++++++++++++++++++---------------
 drivers/slimbus/slimbus.h   |  4 ++
 include/linux/slimbus.h     | 14 ++++---
 5 files changed, 110 insertions(+), 37 deletions(-)

-- 
2.16.2

[PATCH v3 1/8] slimbus: core: rearrange slim_eaddr structure

[Srinivas Kandagatla]

Rearrange struct slim_eaddr so that the structure is packed correctly
to be able to send in SLIMBus messages.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 include/linux/slimbus.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/linux/slimbus.h b/include/linux/slimbus.h
index c36cf121d2cd..90af9eb26615 100644
--- a/include/linux/slimbus.h
+++ b/include/linux/slimbus.h
@@ -14,16 +14,16 @@ extern struct bus_type slimbus_bus;
 
 /**
  * struct slim_eaddr - Enumeration address for a SLIMbus device
- * @manf_id: Manufacturer Id for the device
- * @prod_code: Product code
- * @dev_index: Device index
  * @instance: Instance value
+ * @dev_index: Device index
+ * @prod_code: Product code
+ * @manf_id: Manufacturer Id for the device
  */
 struct slim_eaddr {
-	u16 manf_id;
-	u16 prod_code;
-	u8 dev_index;
 	u8 instance;
+	u8 dev_index;
+	u16 prod_code;
+	u16 manf_id;
 } __packed;
 
 /**
-- 
2.16.2

[PATCH v3 1/8] slimbus: core: rearrange slim_eaddr structure

[Srinivas Kandagatla]

Rearrange struct slim_eaddr so that the structure is packed correctly
to be able to send in SLIMBus messages.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 include/linux/slimbus.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/linux/slimbus.h b/include/linux/slimbus.h
index c36cf121d2cd..90af9eb26615 100644
--- a/include/linux/slimbus.h
+++ b/include/linux/slimbus.h
@@ -14,16 +14,16 @@ extern struct bus_type slimbus_bus;
 
 /**
  * struct slim_eaddr - Enumeration address for a SLIMbus device
- * @manf_id: Manufacturer Id for the device
- * @prod_code: Product code
- * @dev_index: Device index
  * @instance: Instance value
+ * @dev_index: Device index
+ * @prod_code: Product code
+ * @manf_id: Manufacturer Id for the device
  */
 struct slim_eaddr {
-	u16 manf_id;
-	u16 prod_code;
-	u8 dev_index;
 	u8 instance;
+	u8 dev_index;
+	u16 prod_code;
+	u16 manf_id;
 } __packed;
 
 /**
-- 
2.16.2

[PATCH v3 2/8] slimbus: core: add need_tid flag to slim_msg_txn

[Srinivas Kandagatla]

Add need_tid flag to txn, this flag can be set before start of transcation.
Having this flag would avoid calling slim_tid_txn() multiple times on the
same txn. Also it is handy for controller drivers too.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/slimbus.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/slimbus/slimbus.h b/drivers/slimbus/slimbus.h
index 79f8e05d92dd..3ec5a85fba8e 100644
--- a/drivers/slimbus/slimbus.h
+++ b/drivers/slimbus/slimbus.h
@@ -102,6 +102,7 @@ struct slim_framer {
  * @msg: Elemental access message to be read/written
  * @comp: completion if read/write is synchronous, used internally
  *	for tid based transactions.
+ * @need_tid: flag indicating if a tid is required for this txn
  */
 struct slim_msg_txn {
 	u8			rl;
@@ -113,6 +114,7 @@ struct slim_msg_txn {
 	u8			la;
 	struct slim_val_inf	*msg;
 	struct	completion	*comp;
+	bool			need_tid;
 };
 
 /* Frequently used message transaction structures */
-- 
2.16.2

[PATCH v3 3/8] slimbus: messaging: pass correct wbuf

[Srinivas Kandagatla]

There seems to be a typo while filling msg for slim_write, wbuf is
set to NULL instead of rbuf.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/messaging.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index 457ea1f8db30..5a2ff01b394c 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -307,7 +307,7 @@ int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val)
 {
 	struct slim_val_inf msg;
 
-	slim_fill_msg(&msg, addr, count,  val, NULL);
+	slim_fill_msg(&msg, addr, count,  NULL, val);
 
 	return slim_xfer_msg(sdev, &msg, SLIM_MSG_MC_CHANGE_VALUE);
 }
-- 
2.16.2

[PATCH v3 3/8] slimbus: messaging: pass correct wbuf

[Srinivas Kandagatla]

There seems to be a typo while filling msg for slim_write, wbuf is
set to NULL instead of rbuf.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/messaging.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index 457ea1f8db30..5a2ff01b394c 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -307,7 +307,7 @@ int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val)
 {
 	struct slim_val_inf msg;
 
-	slim_fill_msg(&msg, addr, count,  val, NULL);
+	slim_fill_msg(&msg, addr, count,  NULL, val);
 
 	return slim_xfer_msg(sdev, &msg, SLIM_MSG_MC_CHANGE_VALUE);
 }
-- 
2.16.2

[PATCH v3 4/8] slimbus: messaging: remove multiple calls to pm_runtime_mark_last_busy

[Srinivas Kandagatla]

There seems to be a multiple calls to pm_runtime_mark_last_busy(),
which looks like a typo.
Fix this by properly adding pm_runtime_put_autosuspend to put controller
in auto suspend state.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/messaging.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index 5a2ff01b394c..1c57b631031a 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -139,7 +139,7 @@ int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
 		 * if there was error during this transaction
 		 */
 		pm_runtime_mark_last_busy(ctrl->dev);
-		pm_runtime_mark_last_busy(ctrl->dev);
+		pm_runtime_put_autosuspend(ctrl->dev);
 	}
 	return ret;
 }
-- 
2.16.2

[PATCH v3 5/8] slimbus: messaging: initialize completion correctly

[Srinivas Kandagatla]

slim_val_inf can contain random value from stack, make sure the completion
is initialized to NULL while filling the msg.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/messaging.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index 1c57b631031a..e3605ed1c459 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -246,6 +246,7 @@ static void slim_fill_msg(struct slim_val_inf *msg, u32 addr,
 	msg->num_bytes = count;
 	msg->rbuf = rbuf;
 	msg->wbuf = wbuf;
+	msg->comp = NULL;
 }
 
 /**
-- 
2.16.2

[PATCH v3 6/8] slimbus: qcom: remove redundant depends in Kconfig

[Srinivas Kandagatla]

QCOM SLIMBus controller is already under a 'if SLIMBUS' in Kconfig,
having depends on SLIMBUS is totally redundant. Just remove it.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/slimbus/Kconfig b/drivers/slimbus/Kconfig
index 1a632fad597e..bfb78d9a6583 100644
--- a/drivers/slimbus/Kconfig
+++ b/drivers/slimbus/Kconfig
@@ -15,7 +15,6 @@ if SLIMBUS
 # SLIMbus controllers
 config SLIM_QCOM_CTRL
 	tristate "Qualcomm SLIMbus Manager Component"
-	depends on SLIMBUS
 	depends on HAS_IOMEM
 	help
 	  Select driver if Qualcomm's SLIMbus Manager Component is
-- 
2.16.2

[PATCH v3 6/8] slimbus: qcom: remove redundant depends in Kconfig

[Srinivas Kandagatla]

QCOM SLIMBus controller is already under a 'if SLIMBUS' in Kconfig,
having depends on SLIMBUS is totally redundant. Just remove it.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/slimbus/Kconfig b/drivers/slimbus/Kconfig
index 1a632fad597e..bfb78d9a6583 100644
--- a/drivers/slimbus/Kconfig
+++ b/drivers/slimbus/Kconfig
@@ -15,7 +15,6 @@ if SLIMBUS
 # SLIMbus controllers
 config SLIM_QCOM_CTRL
 	tristate "Qualcomm SLIMbus Manager Component"
-	depends on SLIMBUS
 	depends on HAS_IOMEM
 	help
 	  Select driver if Qualcomm's SLIMbus Manager Component is
-- 
2.16.2

[PATCH v3 7/8] slimbus: messaging: add slim_prepare_txn() helper function

[Srinivas Kandagatla]

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@linaro.org>
---
 drivers/slimbus/messaging.c | 84 ++++++++++++++++++++++++++++++---------------
 drivers/slimbus/slimbus.h   |  2 ++
 2 files changed, 58 insertions(+), 28 deletions(-)

diff --git a/drivers/slimbus/messaging.c b/drivers/slimbus/messaging.c
index e3605ed1c459..cfffa1dece61 100644
--- a/drivers/slimbus/messaging.c
+++ b/drivers/slimbus/messaging.c
@@ -55,6 +55,46 @@ 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 if msg does not have completion
+ * @need_tid: flag to indicate if tid is required for this txn
+ * note, user defined commands would need tid.
+ *
+ * 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;
+
+	txn->need_tid = need_tid;
+	if (!need_tid)
+		return 0;
+
+	spin_lock_irqsave(&ctrl->txn_lock, flags);
+	ret = idr_alloc(&ctrl->tid_idr, txn, 0, SLIM_MAX_TIDS, GFP_ATOMIC);
+	if (ret < 0)
+		goto err;
+
+	txn->tid = ret;
+	if (!txn->msg->comp)
+		txn->comp = done;
+	else
+		txn->comp = txn->msg->comp;
+
+err:
+	spin_unlock_irqrestore(&ctrl->txn_lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(slim_prepare_txn);
+
 /**
  * slim_do_transfer() - Process a SLIMbus-messaging transaction
  *
@@ -70,10 +110,9 @@ 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 +133,8 @@ 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 +142,7 @@ 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 +152,14 @@ 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;
 }
@@ -205,6 +225,8 @@ 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 +254,16 @@ 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/slimbus.h b/drivers/slimbus/slimbus.h
index 3ec5a85fba8e..8266e53535cb 100644
--- a/drivers/slimbus/slimbus.h
+++ b/drivers/slimbus/slimbus.h
@@ -242,6 +242,8 @@ 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

[PATCH v3 8/8] slimbus: core: add of_slim_device_get() helper

[Srinivas Kandagatla]

On SLIMBus controllers like Qcom NGD(non ported device), controller
can request logical address once the remote side is powered, having a
helper function like this to explicitly enumerate the bus is helpful.
Also codec drivers which are taking to interface device would need
such a helper too.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/slimbus/core.c  | 39 +++++++++++++++++++++++++++++++++++++++
 include/linux/slimbus.h |  2 ++
 2 files changed, 41 insertions(+)

diff --git a/drivers/slimbus/core.c b/drivers/slimbus/core.c
index 7ddfc675b131..88248a4ecad9 100644
--- a/drivers/slimbus/core.c
+++ b/drivers/slimbus/core.c
@@ -356,6 +356,45 @@ struct slim_device *slim_get_device(struct slim_controller *ctrl,
 }
 EXPORT_SYMBOL_GPL(slim_get_device);
 
+static int of_slim_match_dev(struct device *dev, void *data)
+{
+	struct device_node *np = data;
+	struct slim_device *sbdev = to_slim_device(dev);
+
+	return (sbdev->dev.of_node == np);
+}
+
+static struct slim_device *of_find_slim_device(struct slim_controller *ctrl,
+					       struct device_node *np)
+{
+	struct slim_device *sbdev;
+	struct device *dev;
+
+	dev = device_find_child(ctrl->dev, np, of_slim_match_dev);
+	if (dev) {
+		sbdev = to_slim_device(dev);
+		return sbdev;
+	}
+
+	return NULL;
+}
+
+/**
+ * of_slim_get_device() - get handle to a device using dt node.
+ *
+ * @ctrl: Controller on which this device will be added/queried
+ * @np: node pointer to device
+ *
+ * Return: pointer to a device if it has already reported. Creates a new
+ * device and returns pointer to it if the device has not yet enumerated.
+ */
+struct slim_device *of_slim_get_device(struct slim_controller *ctrl,
+				       struct device_node *np)
+{
+	return of_find_slim_device(ctrl, np);
+}
+EXPORT_SYMBOL_GPL(of_slim_get_device);
+
 static int slim_device_alloc_laddr(struct slim_device *sbdev,
 				   bool report_present)
 {
diff --git a/include/linux/slimbus.h b/include/linux/slimbus.h
index 90af9eb26615..63801bcc5e60 100644
--- a/include/linux/slimbus.h
+++ b/include/linux/slimbus.h
@@ -138,6 +138,8 @@ static inline void slim_set_devicedata(struct slim_device *dev, void *data)
 	dev_set_drvdata(&dev->dev, data);
 }
 
+struct slim_device *of_slim_get_device(struct slim_controller *ctrl,
+				       struct device_node *np);
 struct slim_device *slim_get_device(struct slim_controller *ctrl,
 				    struct slim_eaddr *e_addr);
 int slim_get_logical_addr(struct slim_device *sbdev);
-- 
2.16.2