[PATCH v2 8/8] firmware: arm_scmi: Remove legacy transport-layer code

[Cristian Marussi]

Since all SCMI transports have been made standalone drivers, remove all the
core SCMI stack legacy support that was needed to run transports as built
into the stack.

Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
 drivers/firmware/arm_scmi/common.h | 18 ------
 drivers/firmware/arm_scmi/driver.c | 96 ++++--------------------------
 drivers/firmware/arm_scmi/msg.c    |  2 +-
 drivers/firmware/arm_scmi/shmem.c  |  2 +-
 4 files changed, 15 insertions(+), 103 deletions(-)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 28d52b9102c3..0a31d3b2f2c2 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -183,7 +183,6 @@ struct scmi_chan_info {
 /**
  * struct scmi_transport_ops - Structure representing a SCMI transport ops
  *
- * @link_supplier: Optional callback to add link to a supplier device
  * @chan_available: Callback to check if channel is available or not
  * @chan_setup: Callback to allocate and setup a channel
  * @chan_free: Callback to free a channel
@@ -198,7 +197,6 @@ struct scmi_chan_info {
  * @poll_done: Callback to poll transfer status
  */
 struct scmi_transport_ops {
-	int (*link_supplier)(struct device *dev);
 	bool (*chan_available)(struct device_node *of_node, int idx);
 	int (*chan_setup)(struct scmi_chan_info *cinfo, struct device *dev,
 			  bool tx);
@@ -219,12 +217,6 @@ struct scmi_transport_ops {
 /**
  * struct scmi_desc - Description of SoC integration
  *
- * @transport_init: An optional function that a transport can provide to
- *		    initialize some transport-specific setup during SCMI core
- *		    initialization, so ahead of SCMI core probing.
- * @transport_exit: An optional function that a transport can provide to
- *		    de-initialize some transport-specific setup during SCMI core
- *		    de-initialization, so after SCMI core removal.
  * @ops: Pointer to the transport specific ops structure
  * @max_rx_timeout_ms: Timeout for communication with SoC (in Milliseconds)
  * @max_msg: Maximum number of messages for a channel type (tx or rx) that can
@@ -245,8 +237,6 @@ struct scmi_transport_ops {
  *		    when requested.
  */
 struct scmi_desc {
-	int (*transport_init)(void);
-	void (*transport_exit)(void);
 	const struct scmi_transport_ops *ops;
 	int max_rx_timeout_ms;
 	int max_msg;
@@ -287,8 +277,6 @@ int scmi_xfer_raw_wait_for_message_response(struct scmi_chan_info *cinfo,
 					    struct scmi_xfer *xfer,
 					    unsigned int timeout_ms);
 
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv);
-
 enum scmi_bad_msg {
 	MSG_UNEXPECTED = -1,
 	MSG_INVALID = -2,
@@ -297,9 +285,6 @@ enum scmi_bad_msg {
 	MSG_MBOX_SPURIOUS = -5,
 };
 
-void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
-			    enum scmi_bad_msg err);
-
 /* shmem related declarations */
 struct scmi_shared_mem;
 
@@ -448,9 +433,6 @@ static struct platform_driver __trans##_driver = {			\
 	.remove_new = __trans##_remove,					\
 }
 
-extern const struct scmi_shared_mem_operations scmi_shmem_ops;
-extern const struct scmi_message_operations scmi_msg_ops;
-
 void scmi_notification_instance_data_set(const struct scmi_handle *handle,
 					 void *priv);
 void *scmi_notification_instance_data_get(const struct scmi_handle *handle);
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index 2a1f87c97abe..ea0595193dec 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -194,6 +194,11 @@ struct scmi_info {
 #define bus_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, bus_nb)
 #define req_nb_to_scmi_info(nb)	container_of(nb, struct scmi_info, dev_req_nb)
 
+static void scmi_rx_callback(struct scmi_chan_info *cinfo,
+			     u32 msg_hdr, void *priv);
+static void scmi_bad_message_trace(struct scmi_chan_info *cinfo,
+				   u32 msg_hdr, enum scmi_bad_msg err);
+
 static struct scmi_transport_core_operations scmi_trans_core_ops = {
 	.bad_message_trace = scmi_bad_message_trace,
 	.rx_callback = scmi_rx_callback,
@@ -838,8 +843,8 @@ scmi_xfer_lookup_unlocked(struct scmi_xfers_info *minfo, u16 xfer_id)
  * timed-out message that arrives and as such, can be traced only referring to
  * the header content, since the payload is missing/unreliable.
  */
-void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
-			    enum scmi_bad_msg err)
+static void scmi_bad_message_trace(struct scmi_chan_info *cinfo, u32 msg_hdr,
+				   enum scmi_bad_msg err)
 {
 	char *tag;
 	struct scmi_info *info = handle_to_scmi_info(cinfo->handle);
@@ -1165,7 +1170,8 @@ static void scmi_handle_response(struct scmi_chan_info *cinfo,
  * NOTE: This function will be invoked in IRQ context, hence should be
  * as optimal as possible.
  */
-void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr, void *priv)
+static void scmi_rx_callback(struct scmi_chan_info *cinfo, u32 msg_hdr,
+			     void *priv)
 {
 	u8 msg_type = MSG_XTRACT_TYPE(msg_hdr);
 
@@ -2988,14 +2994,11 @@ static int scmi_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct device_node *child, *np = dev->of_node;
 
-	desc = of_device_get_match_data(dev);
+	desc = scmi_transport_lookup(dev);
 	if (!desc) {
-		desc = scmi_transport_lookup(dev);
-		if (!desc) {
-			err_str = "transport invalid\n";
-			ret = -EINVAL;
-			goto out_err;
-		}
+		err_str = "transport invalid\n";
+		ret = -EINVAL;
+		goto out_err;
 	}
 
 	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
@@ -3035,14 +3038,6 @@ static int scmi_probe(struct platform_device *pdev)
 			 info->atomic_threshold);
 	handle->is_transport_atomic = scmi_is_transport_atomic;
 
-	if (desc->ops->link_supplier) {
-		ret = desc->ops->link_supplier(dev);
-		if (ret) {
-			err_str = "transport not ready\n";
-			goto clear_ida;
-		}
-	}
-
 	/* Setup all channels described in the DT at first */
 	ret = scmi_channels_setup(info);
 	if (ret) {
@@ -3249,72 +3244,16 @@ static struct attribute *versions_attrs[] = {
 };
 ATTRIBUTE_GROUPS(versions);
 
-/* Each compatible listed below must have descriptor associated with it */
-static const struct of_device_id scmi_of_match[] = {
-	{ /* Sentinel */ },
-};
-
-MODULE_DEVICE_TABLE(of, scmi_of_match);
-
 static struct platform_driver scmi_driver = {
 	.driver = {
 		   .name = "arm-scmi",
 		   .suppress_bind_attrs = true,
-		   .of_match_table = scmi_of_match,
 		   .dev_groups = versions_groups,
 		   },
 	.probe = scmi_probe,
 	.remove_new = scmi_remove,
 };
 
-/**
- * __scmi_transports_setup  - Common helper to call transport-specific
- * .init/.exit code if provided.
- *
- * @init: A flag to distinguish between init and exit.
- *
- * Note that, if provided, we invoke .init/.exit functions for all the
- * transports currently compiled in.
- *
- * Return: 0 on Success.
- */
-static inline int __scmi_transports_setup(bool init)
-{
-	int ret = 0;
-	const struct of_device_id *trans;
-
-	for (trans = scmi_of_match; trans->data; trans++) {
-		const struct scmi_desc *tdesc = trans->data;
-
-		if ((init && !tdesc->transport_init) ||
-		    (!init && !tdesc->transport_exit))
-			continue;
-
-		if (init)
-			ret = tdesc->transport_init();
-		else
-			tdesc->transport_exit();
-
-		if (ret) {
-			pr_err("SCMI transport %s FAILED initialization!\n",
-			       trans->compatible);
-			break;
-		}
-	}
-
-	return ret;
-}
-
-static int __init scmi_transports_init(void)
-{
-	return __scmi_transports_setup(true);
-}
-
-static void __exit scmi_transports_exit(void)
-{
-	__scmi_transports_setup(false);
-}
-
 static struct dentry *scmi_debugfs_init(void)
 {
 	struct dentry *d;
@@ -3330,17 +3269,10 @@ static struct dentry *scmi_debugfs_init(void)
 
 static int __init scmi_driver_init(void)
 {
-	int ret;
-
 	/* Bail out if no SCMI transport was configured */
 	if (WARN_ON(!IS_ENABLED(CONFIG_ARM_SCMI_HAVE_TRANSPORT)))
 		return -EINVAL;
 
-	/* Initialize any compiled-in transport which provided an init/exit */
-	ret = scmi_transports_init();
-	if (ret)
-		return ret;
-
 	if (IS_ENABLED(CONFIG_ARM_SCMI_HAVE_SHMEM))
 		scmi_trans_core_ops.shmem = scmi_shared_mem_operations_get();
 
@@ -3380,8 +3312,6 @@ static void __exit scmi_driver_exit(void)
 	scmi_powercap_unregister();
 	scmi_pinctrl_unregister();
 
-	scmi_transports_exit();
-
 	platform_driver_unregister(&scmi_driver);
 
 	debugfs_remove_recursive(scmi_top_dentry);
diff --git a/drivers/firmware/arm_scmi/msg.c b/drivers/firmware/arm_scmi/msg.c
index 0bed1d2825af..ca916817878d 100644
--- a/drivers/firmware/arm_scmi/msg.c
+++ b/drivers/firmware/arm_scmi/msg.c
@@ -110,7 +110,7 @@ static void msg_fetch_notification(struct scmi_msg_payld *msg, size_t len,
 	memcpy(xfer->rx.buf, msg->msg_payload, xfer->rx.len);
 }
 
-const struct scmi_message_operations scmi_msg_ops = {
+static const struct scmi_message_operations scmi_msg_ops = {
 	.tx_prepare = msg_tx_prepare,
 	.command_size = msg_command_size,
 	.response_size = msg_response_size,
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index b1fc0c31495b..e17eb603d871 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -176,7 +176,7 @@ static void __iomem *shmem_setup_iomap(struct scmi_chan_info *cinfo,
 	return addr;
 }
 
-const struct scmi_shared_mem_operations scmi_shmem_ops = {
+static const struct scmi_shared_mem_operations scmi_shmem_ops = {
 	.tx_prepare = shmem_tx_prepare,
 	.read_header = shmem_read_header,
 	.fetch_response = shmem_fetch_response,
-- 
2.45.2