[PATCH v4 04/16] misc: bcm-vk: add misc device to Broadcom VK driver

Scott Branden
2020-09-29T00:12:57Z

Add misc device base support to create and remove devnode.
Additional misc functions for open/read/write/release/ioctl/sysfs, etc
will be added in follow on commits to allow for individual review.

Co-developed-by: Desmond Yan <desmond.yan@broadcom.com>
Signed-off-by: Desmond Yan <desmond.yan@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
---
drivers/misc/bcm-vk/bcm_vk.h | 2 ++
drivers/misc/bcm-vk/bcm_vk_dev.c | 36 +++++++++++++++++++++++++++++++-
2 files changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/misc/bcm-vk/bcm_vk.h b/drivers/misc/bcm-vk/bcm_vk.h
index c4fb61a84e41..0a366db693c8 100644
--- a/drivers/misc/bcm-vk/bcm_vk.h
+++ b/drivers/misc/bcm-vk/bcm_vk.h
@@ -7,6 +7,7 @@
#define BCM_VK_H

#include <linux/firmware.h>
+#include <linux/miscdevice.h>
#include <linux/pci.h>
#include <linux/sched/signal.h>

@@ -214,6 +215,7 @@ struct bcm_vk {

struct bcm_vk_dauth_info dauth_info;

+ struct miscdevice miscdev;
int devid; /* dev id allocated */

struct workqueue_struct *wq_thread;
diff --git a/drivers/misc/bcm-vk/bcm_vk_dev.c b/drivers/misc/bcm-vk/bcm_vk_dev.c
index 36f04fd0a54e..cb2e315881d6 100644
--- a/drivers/misc/bcm-vk/bcm_vk_dev.c
+++ b/drivers/misc/bcm-vk/bcm_vk_dev.c
@@ -7,6 +7,7 @@
#include <linux/dma-mapping.h>
#include <linux/firmware.h>
#include <linux/fs.h>
+#include <linux/idr.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/pci_regs.h>
@@ -638,6 +639,7 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
char name[20];
struct bcm_vk *vk;
struct device *dev = &pdev->dev;
+ struct miscdevice *misc_device;
u32 boot_status;

vk = kzalloc(sizeof(*vk), GFP_KERNEL);
@@ -713,6 +715,19 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)

vk->devid = id;
snprintf(name, sizeof(name), DRV_MODULE_NAME ".%d", id);
+ misc_device = &vk->miscdev;
+ misc_device->minor = MISC_DYNAMIC_MINOR;
+ misc_device->name = kstrdup(name, GFP_KERNEL);
+ if (!misc_device->name) {
+ err = -ENOMEM;
+ goto err_ida_remove;
+ }
+
+ err = misc_register(misc_device);
+ if (err) {
+ dev_err(dev, "failed to register device\n");
+ goto err_kfree_name;
+ }

INIT_WORK(&vk->wq_work, bcm_vk_wq_handler);

@@ -721,7 +736,7 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
if (!vk->wq_thread) {
dev_err(dev, "Fail to create workqueue thread\n");
err = -ENOMEM;
- goto err_ida_remove;
+ goto err_misc_deregister;
}

/* sync other info */
@@ -743,11 +758,20 @@ static int bcm_vk_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
}
}

+ dev_dbg(dev, "BCM-VK:%u created, 0x%p\n", id, vk);
+
return 0;

err_destroy_workqueue:
destroy_workqueue(vk->wq_thread);

+err_misc_deregister:
+ misc_deregister(misc_device);
+
+err_kfree_name:
+ kfree(misc_device->name);
+ misc_device->name = NULL;
+
err_ida_remove:
ida_simple_remove(&bcm_vk_ida, id);

@@ -774,6 +798,7 @@ static void bcm_vk_remove(struct pci_dev *pdev)
{
int i;
struct bcm_vk *vk = pci_get_drvdata(pdev);
+ struct miscdevice *misc_device = &vk->miscdev;

/*
* Trigger a reset to card and wait enough time for UCODE to rerun,
@@ -788,6 +813,13 @@ static void bcm_vk_remove(struct pci_dev *pdev)
dma_free_coherent(&pdev->dev, nr_scratch_pages * PAGE_SIZE,
vk->tdma_vaddr, vk->tdma_addr);

+ /* remove if name is set which means misc dev registered */
+ if (misc_device->name) {
+ misc_deregister(misc_device);
+ kfree(misc_device->name);
+ ida_simple_remove(&bcm_vk_ida, vk->devid);
+ }
+
cancel_work_sync(&vk->wq_work);
destroy_workqueue(vk->wq_thread);

@@ -796,6 +828,8 @@ static void bcm_vk_remove(struct pci_dev *pdev)
pci_iounmap(pdev, vk->bar[i]);
}

+ dev_dbg(&pdev->dev, "BCM-VK:%d released\n", vk->devid);
+
pci_release_regions(pdev);
pci_free_irq_vectors(pdev);
pci_disable_device(pdev);
--
2.17.1