staging: vc04_services: vchiq_arm: Split driver static and runtime data

vchiq_drvdata combines two types of book-keeping data. There is
platform-specific static data (for e.g. cache lines size) and then
data needed for book-keeping at runtime.

Split the data into two structures: struct vchiq_platform_info and
struct vchiq_drv_mgmt. The vchiq_drv_mgmt is allocated at runtime
during probe and will be extended in subsequent patches to remove
all global variables allocated.

No functional changes intended in this patch.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/20240412075743.60712-3-umang.jain@ideasonboard.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c

@@ -71,16 +71,11 @@ struct vchiq_state g_state;
 static struct vchiq_device *bcm2835_audio;
 static struct vchiq_device *bcm2835_camera;
 
-struct vchiq_drvdata {
-	const unsigned int cache_line_size;
-	struct rpi_firmware *fw;
-};
-
-static struct vchiq_drvdata bcm2835_drvdata = {
+static const struct vchiq_platform_info bcm2835_info = {
 	.cache_line_size = 32,
 };
 
-static struct vchiq_drvdata bcm2836_drvdata = {
+static const struct vchiq_platform_info bcm2836_info = {
 	.cache_line_size = 64,
 };
 
@@ -466,8 +461,8 @@ free_pagelist(struct vchiq_instance *instance, struct vchiq_pagelist_info *pagel
 static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state *state)
 {
 	struct device *dev = &pdev->dev;
-	struct vchiq_drvdata *drvdata = platform_get_drvdata(pdev);
-	struct rpi_firmware *fw = drvdata->fw;
+	struct vchiq_drv_mgmt *drv_mgmt = platform_get_drvdata(pdev);
+	struct rpi_firmware *fw = drv_mgmt->fw;
 	struct vchiq_slot_zero *vchiq_slot_zero;
 	void *slot_mem;
 	dma_addr_t slot_phys;
@@ -484,7 +479,7 @@ static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state
 	if (err < 0)
 		return err;
 
-	g_cache_line_size = drvdata->cache_line_size;
+	g_cache_line_size = drv_mgmt->info->cache_line_size;
 	g_fragments_size = 2 * g_cache_line_size;
 
 	/* Allocate space for the channels in coherent memory */
@@ -1703,22 +1698,21 @@ void vchiq_platform_conn_state_changed(struct vchiq_state *state,
 }
 
 static const struct of_device_id vchiq_of_match[] = {
-	{ .compatible = "brcm,bcm2835-vchiq", .data = &bcm2835_drvdata },
-	{ .compatible = "brcm,bcm2836-vchiq", .data = &bcm2836_drvdata },
+	{ .compatible = "brcm,bcm2835-vchiq", .data = &bcm2835_info },
+	{ .compatible = "brcm,bcm2836-vchiq", .data = &bcm2836_info },
 	{},
 };
 MODULE_DEVICE_TABLE(of, vchiq_of_match);
 
 static int vchiq_probe(struct platform_device *pdev)
 {
 	struct device_node *fw_node;
-	const struct of_device_id *of_id;
-	struct vchiq_drvdata *drvdata;
+	const struct vchiq_platform_info *info;
+	struct vchiq_drv_mgmt *mgmt;
 	int err;
 
-	of_id = of_match_node(vchiq_of_match, pdev->dev.of_node);
-	drvdata = (struct vchiq_drvdata *)of_id->data;
-	if (!drvdata)
+	info = of_device_get_match_data(&pdev->dev);
+	if (!info)
 		return -EINVAL;
 
 	fw_node = of_find_compatible_node(NULL, NULL,
@@ -1728,12 +1722,17 @@ static int vchiq_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
-	drvdata->fw = devm_rpi_firmware_get(&pdev->dev, fw_node);
+	mgmt = kzalloc(sizeof(*mgmt), GFP_KERNEL);
+	if (!mgmt)
+		return -ENOMEM;
+
+	mgmt->fw = devm_rpi_firmware_get(&pdev->dev, fw_node);
 	of_node_put(fw_node);
-	if (!drvdata->fw)
+	if (!mgmt->fw)
 		return -EPROBE_DEFER;
 
-	platform_set_drvdata(pdev, drvdata);
+	mgmt->info = info;
+	platform_set_drvdata(pdev, mgmt);
 
 	err = vchiq_platform_init(pdev, &g_state);
 	if (err)
@@ -1767,10 +1766,14 @@ static int vchiq_probe(struct platform_device *pdev)
 
 static void vchiq_remove(struct platform_device *pdev)
 {
+	struct vchiq_drv_mgmt *mgmt = dev_get_drvdata(&pdev->dev);
+
 	vchiq_device_unregister(bcm2835_audio);
 	vchiq_device_unregister(bcm2835_camera);
 	vchiq_debugfs_deinit();
 	vchiq_deregister_chrdev();
+
+	kfree(mgmt);
 }
 
 static struct platform_driver vchiq_driver = {