Hi Kieran, On 6/29/23 12:44 AM, Kieran Bingham wrote:
Quoting Umang Jain (2023-06-27 21:16:26)Register the bcm2835-camera with the vchiq_bus_type instead of using platform driver/device. Also the VCHIQ firmware doesn't support device enumeration, hence one has to maintain a list of devices to be registered in the interface. Signed-off-by: Umang Jain <umang.jain@xxxxxxxxxxxxxxxx> --- .../bcm2835-camera/bcm2835-camera.c | 16 +++++++------- .../interface/vchiq_arm/vchiq_arm.c | 21 ++++++++++++++++--- 2 files changed, 26 insertions(+), 11 deletions(-) diff --git a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c index 346d00df815a..f37b2a881d92 100644 --- a/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c +++ b/drivers/staging/vc04_services/bcm2835-camera/bcm2835-camera.c @@ -24,8 +24,9 @@ #include <media/v4l2-event.h> #include <media/v4l2-common.h> #include <linux/delay.h> -#include <linux/platform_device.h>+#include "../interface/vchiq_arm/vchiq_arm.h"+#include "../interface/vchiq_arm/vchiq_device.h" #include "../vchiq-mmal/mmal-common.h" #include "../vchiq-mmal/mmal-encodings.h" #include "../vchiq-mmal/mmal-vchiq.h" @@ -1841,7 +1842,7 @@ static struct v4l2_format default_v4l2_format = { .fmt.pix.sizeimage = 1024 * 768, };-static int bcm2835_mmal_probe(struct platform_device *pdev)+static int bcm2835_mmal_probe(struct vchiq_device *device) { int ret; struct bcm2835_mmal_dev *dev; @@ -1896,7 +1897,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev) &camera_instance); ret = v4l2_device_register(NULL, &dev->v4l2_dev); if (ret) { - dev_err(&pdev->dev, "%s: could not register V4L2 device: %d\n", + dev_err(&device->dev, "%s: could not register V4L2 device: %d\n", __func__, ret); goto free_dev; } @@ -1976,7 +1977,7 @@ static int bcm2835_mmal_probe(struct platform_device *pdev) return ret; }-static void bcm2835_mmal_remove(struct platform_device *pdev)+static void bcm2835_mmal_remove(struct vchiq_device *device) { int camera; struct vchiq_mmal_instance *instance = gdev[0]->instance; @@ -1988,17 +1989,16 @@ static void bcm2835_mmal_remove(struct platform_device *pdev) vchiq_mmal_finalise(instance); }-static struct platform_driver bcm2835_camera_driver = {+static struct vchiq_driver bcm2835_camera_driver = { .probe = bcm2835_mmal_probe, - .remove_new = bcm2835_mmal_remove, + .remove = bcm2835_mmal_remove, .driver = { .name = "bcm2835-camera", }, };-module_platform_driver(bcm2835_camera_driver)+module_vchiq_driver(bcm2835_camera_driver)MODULE_DESCRIPTION("Broadcom 2835 MMAL video capture");MODULE_AUTHOR("Vincent Sanders"); MODULE_LICENSE("GPL"); -MODULE_ALIAS("platform:bcm2835-camera");This bit worries me. I think that's how module autoloading is handled. Can you check into the details of MODULE_ALIAS and follow the rabbit hole for a bit? It's a few years since I last went down there so I can't remember the specifics right now.
vchiq_probe() will register both the bcm2385_audio and bcm2835-camera hence, we don't need MODULE_ALIAS for those two.
So what I also tested is that, when bcm2835_vchiq loads, it will auto-load both audio and camera with it (since these are child devices of vchiq). I think that's the correct way.
Except for that, I think this looks good.diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c index e8d40f891449..79d4d0eeb5fb 100644 --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c @@ -67,7 +67,6 @@ int vchiq_susp_log_level = VCHIQ_LOG_ERROR; DEFINE_SPINLOCK(msg_queue_spinlock); struct vchiq_state g_state;-static struct platform_device *bcm2835_camera;static struct platform_device *bcm2835_audio;struct vchiq_drvdata {@@ -134,6 +133,15 @@ struct vchiq_pagelist_info { unsigned int scatterlist_mapped; };+/*+ * The devices implemented in the VCHIQ firmware are not discoverable, + * so we need to maintain a list of them in order to register them with + * the interface. + */ +static const char *const vchiq_devices[] = { + "bcm2835-camera", +}; + static void __iomem *g_regs; /* This value is the size of the L2 cache lines as understood by the * VPU firmware, which determines the required alignment of the @@ -1798,6 +1806,7 @@ static int vchiq_probe(struct platform_device *pdev) struct device_node *fw_node; const struct of_device_id *of_id; struct vchiq_drvdata *drvdata; + unsigned int i; int err;of_id = of_match_node(vchiq_of_match, pdev->dev.of_node);@@ -1840,9 +1849,15 @@ static int vchiq_probe(struct platform_device *pdev) goto error_exit; }- bcm2835_camera = vchiq_register_child(pdev, "bcm2835-camera");bcm2835_audio = vchiq_register_child(pdev, "bcm2835_audio");+ for (i = 0; i < ARRAY_SIZE(vchiq_devices); i++) {+ err = vchiq_device_register(&pdev->dev, vchiq_devices[i]); + if (err) + dev_err(&pdev->dev, "Failed to register %s vchiq device\n", + vchiq_devices[i]); + } + return 0;failed_platform_init:@@ -1854,7 +1869,7 @@ static int vchiq_probe(struct platform_device *pdev) static void vchiq_remove(struct platform_device *pdev) { platform_device_unregister(bcm2835_audio); - platform_device_unregister(bcm2835_camera); + bus_for_each_dev(&vchiq_bus_type, NULL, NULL, vchiq_device_unregister); vchiq_debugfs_deinit(); vchiq_deregister_chrdev(); } -- 2.39.1
