From: Harshitha Prem <quic_hprem@quicinc.com>

Currently, single device is part of device group abstraction but for multi
link operation, multiple devices have to be combined together. Information
of how many devices involved in grouping can be parsed from device tree and
it would have the valid group id information as well.

Add changes to parse devices involved and group id from device tree file
to form device group

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.0.1-00029-QCAHKSWPL_SILICONZ-1

Signed-off-by: Harshitha Prem <quic_hprem@quicinc.com>
Co-developed-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Co-developed-by: Raj Kumar Bhagat <quic_rajkbhag@quicinc.com>
Signed-off-by: Raj Kumar Bhagat <quic_rajkbhag@quicinc.com>
---
 drivers/net/wireless/ath/ath12k/core.c | 154 +++++++++++++++++++++++--
 drivers/net/wireless/ath/ath12k/core.h |   8 ++
 2 files changed, 151 insertions(+), 11 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/core.c b/drivers/net/wireless/ath/ath12k/core.c
index 3f0f44cbdb4c..91950ee50bf3 100644
--- a/drivers/net/wireless/ath/ath12k/core.c
+++ b/drivers/net/wireless/ath/ath12k/core.c
@@ -9,6 +9,7 @@
 #include <linux/remoteproc.h>
 #include <linux/firmware.h>
 #include <linux/of.h>
+#include <linux/of_graph.h>
 #include "core.h"
 #include "dp_tx.h"
 #include "dp_rx.h"
@@ -1403,6 +1404,7 @@ ath12k_core_hw_group_alloc(u8 id, u8 max_devices)
 	ag->num_devices = max_devices;
 	list_add(&ag->list, &ath12k_hw_group_list);
 	mutex_init(&ag->mutex_lock);
+	ag->mlo_capable = false;
 
 	return ag;
 }
@@ -1417,34 +1419,156 @@ static void ath12k_core_hw_group_free(struct ath12k_hw_group *ag)
 	mutex_unlock(&ath12k_ag_list_lock);
 }
 
+/* This function needs to be used only when dt has multi chip grouping information */
+static struct ath12k_hw_group *ath12k_core_hw_group_find_by_id(u8 group_id)
+{
+	struct ath12k_hw_group *ag;
+
+	/* group ids will be unique only for multi chip group */
+	list_for_each_entry(ag, &ath12k_hw_group_list, list) {
+		if (group_id == ag->id && ag->num_devices > 1)
+			return ag;
+	}
+
+	return NULL;
+}
+
+static int ath12k_core_get_wsi_info(struct ath12k_base *ab,
+				    struct ath12k_wsi_info *wsi_info)
+{
+	struct device_node *wsi_dev, *next_wsi_dev;
+	struct device_node *tx_endpoint, *next_rx_endpoint;
+	int device_count = 0, wsi_master_index = -1;
+
+	wsi_dev = of_get_child_by_name(ab->dev->of_node, "wsi");
+	if (!wsi_dev)
+		return -ENODEV;
+
+	if (of_property_read_u32(wsi_dev, "qcom,wsi-group-id",
+				 &wsi_info->group_id)) {
+		of_node_put(wsi_dev);
+		return -EINVAL;
+	}
+
+	next_wsi_dev = wsi_dev;
+
+	do {
+		if (of_property_read_bool(next_wsi_dev, "qcom,wsi-master"))
+			wsi_master_index = device_count;
+
+		tx_endpoint = of_graph_get_endpoint_by_regs(next_wsi_dev, 0, -1);
+		if (!tx_endpoint) {
+			of_node_put(next_wsi_dev);
+			return -ENODEV;
+		}
+
+		next_rx_endpoint = of_graph_get_remote_endpoint(tx_endpoint);
+		if (!next_rx_endpoint) {
+			of_node_put(next_wsi_dev);
+			of_node_put(tx_endpoint);
+			return -ENODEV;
+		}
+
+		of_node_put(tx_endpoint);
+		of_node_put(next_wsi_dev);
+		next_wsi_dev = of_graph_get_port_parent(next_rx_endpoint);
+		if (!next_wsi_dev) {
+			of_node_put(next_rx_endpoint);
+			return -ENODEV;
+		}
+		of_node_put(next_rx_endpoint);
+
+		device_count++;
+		if (device_count > ATH12K_MAX_SOCS) {
+			ath12k_warn(ab, "device count in DT %d is more than limit %d\n",
+				    device_count, ATH12K_MAX_SOCS);
+			of_node_put(next_wsi_dev);
+			return -EINVAL;
+		}
+	} while (wsi_dev != next_wsi_dev);
+
+	of_node_put(next_wsi_dev);
+	if (wsi_master_index == -1) {
+		ath12k_dbg(ab, ATH12K_DBG_BOOT, "no WSI master defined in DT");
+		return -EINVAL;
+	}
+
+	wsi_info->num_devices = device_count;
+	wsi_info->index = (device_count - wsi_master_index) % device_count;
+	return 0;
+}
+
 static struct ath12k_hw_group *ath12k_core_assign_hw_group(struct ath12k_base *ab)
 {
 	struct ath12k_hw_group *ag;
-	u32 group_id = ATH12K_INVALID_GROUP_ID;
+	struct ath12k_wsi_info *wsi = &ab->wsi_info;
+	int ret;
 
 	lockdep_assert_held(&ath12k_ag_list_lock);
 
-	/* The grouping of multiple devices will be done based on device tree file.
-	 * TODO: device tree file parsing to know about the devices involved in group.
-	 *
-	 * The platforms that do not have any valid group information would have each
-	 * device to be part of its own invalid group.
+	/* The grouping of multiple devices will be done based on device
+	 * tree file.
 	 *
-	 * Currently, we are not parsing any device tree information and hence, grouping
-	 * of multiple devices is not involved. Thus, single device is added to device
-	 * group.
+	 * The platforms that do not have any valid group information would
+	 * have each device to be part of its own invalid group.
+	 */
+	ret = ath12k_core_get_wsi_info(ab, wsi);
+	if (ret) {
+		ath12k_dbg(ab, ATH12K_DBG_BOOT,
+			   "unable to get complete WSI Info from DT, err = %d", ret);
+		wsi->group_id = ATH12K_INVALID_GROUP_ID;
+		wsi->num_devices = 1;
+		wsi->index = 0;
+		goto invalid_group;
+	}
+
+	ath12k_dbg(ab, ATH12K_DBG_BOOT,
+		   "WSI info: group-id: %d, num-devices: %d, index: %d",
+		   wsi->group_id, wsi->num_devices, wsi->index);
+
+	/* Currently only one group of multiple devices are supported,
+	 * since we use group id ATH12K_INVALID_GROUP_ID for single
+	 * device group which didn't have dt entry, there could be many
+	 * groups with same group id, i.e ATH12K_INVALID_GROUP_ID. So
+	 * default group id of ATH12K_INVALID_GROUP_ID combined with
+	 * num devices in ath12k_hw_group determines if the group is
+	 * multi device or single device group
 	 */
-	ag = ath12k_core_hw_group_alloc(group_id, 1);
+	ag = ath12k_core_hw_group_find_by_id(wsi->group_id);
+	if (!ag) {
+		ag = ath12k_core_hw_group_alloc(wsi->group_id, wsi->num_devices);
+		if (!ag) {
+			ath12k_warn(ab, "unable to create new hw group\n");
+			return NULL;
+		}
+		goto exit;
+	} else if (test_bit(ATH12K_GROUP_FLAG_UNREGISTER, &ag->flags)) {
+		ath12k_dbg(ab, ATH12K_DBG_BOOT, "group id %d in unregister state\n",
+			   ag->id);
+		wsi->group_id = ATH12K_INVALID_GROUP_ID;
+		goto invalid_group;
+	} else {
+		goto exit;
+	}
+
+invalid_group:
+	ag = ath12k_core_hw_group_alloc(wsi->group_id, 1);
 	if (!ag) {
 		ath12k_warn(ab, "unable to create new hw group\n");
 		return NULL;
 	}
 	ath12k_dbg(ab, ATH12K_DBG_BOOT, "Single device is added to hardware group\n");
 
+exit:
+	if (ag->num_probed >= ag->num_devices) {
+		ath12k_warn(ab, "unable to add new device to group, max limit reached\n");
+		wsi->group_id = ATH12K_INVALID_GROUP_ID;
+		goto invalid_group;
+	}
+
 	ab->device_id = ag->num_probed++;
 	ag->ab[ab->device_id] = ab;
 	ab->ag = ag;
-	ag->mlo_capable = false;
 
 	return ag;
 }
@@ -1511,6 +1635,14 @@ static void ath12k_core_hw_group_cleanup(struct ath12k_hw_group *ag)
 		return;
 
 	mutex_lock(&ag->mutex_lock);
+
+	if (test_bit(ATH12K_GROUP_FLAG_UNREGISTER, &ag->flags)) {
+		mutex_unlock(&ag->mutex_lock);
+		return;
+	}
+
+	set_bit(ATH12K_GROUP_FLAG_UNREGISTER, &ag->flags);
+
 	ath12k_core_hw_group_stop(ag);
 
 	for (i = 0; i < ag->num_devices; i++) {
diff --git a/drivers/net/wireless/ath/ath12k/core.h b/drivers/net/wireless/ath/ath12k/core.h
index cde35616ba56..6ade7a3cf6ff 100644
--- a/drivers/net/wireless/ath/ath12k/core.h
+++ b/drivers/net/wireless/ath/ath12k/core.h
@@ -211,6 +211,7 @@ enum ath12k_scan_state {
 
 enum ath12k_hw_group_flags {
 	ATH12K_GROUP_FLAG_REGISTERED,
+	ATH12K_GROUP_FLAG_UNREGISTER,
 };
 
 enum ath12k_dev_flags {
@@ -845,6 +846,12 @@ struct ath12k_hw_group {
 	bool mlo_capable;
 };
 
+struct ath12k_wsi_info {
+	u32 group_id;
+	u32 num_devices;
+	u32 index;
+};
+
 /* Master structure to hold the hw data which may be used in core module */
 struct ath12k_base {
 	enum ath12k_hw_rev hw_rev;
@@ -1026,6 +1033,7 @@ struct ath12k_base {
 	struct notifier_block panic_nb;
 
 	struct ath12k_hw_group *ag;
+	struct ath12k_wsi_info wsi_info;
 
 	/* must be last */
 	u8 drv_priv[] __aligned(sizeof(void *));
-- 
2.34.1