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Simple VME FMC Carrier SVEC
Commit 10466a84 authored by Federico Vaga's avatar Federico Vaga Committed by Federico Vaga
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kernel: add minimum char device support 

Signed-off-by: Federico Vaga's avatarFederico Vaga <federico.vaga@vaga.pv.it>
parent 85c022cb
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Showing with 125 additions and 3 deletions
kernel/svec-core.c
View file @ 10466a84
......@@ -12,13 +12,23 @@
* Driver for SVEC (Simple VME FMC carrier) board.
*/
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <vmebus.h>
#define SVEC_MINOR_MAX (64)
static DECLARE_BITMAP(svec_minors, SVEC_MINOR_MAX);
static dev_t basedev;
static struct cdev svec_cdev;
static struct class *svec_class;
/**
* struct svec_dev - SVEC instance
* @vdev VME device instance
......@@ -27,6 +37,80 @@ struct svec_dev {
struct device dev;
};
static inline struct svec_dev *to_svec_dev(struct device *ptr)
{
return container_of(ptr, struct svec_dev, dev);
}
static inline int svec_minor_get(void)
{
int minor;
minor = find_first_zero_bit(svec_minors, SVEC_MINOR_MAX);
set_bit(minor, svec_minors);
return minor;
}
static inline void svec_minor_put(unsigned int minor)
{
clear_bit(minor, svec_minors);
}
/**
* It sets the private data and check that only one user at
* time access this file
*/
static int svec_open(struct inode *inode, struct file *file)
{
pr_info("%s:%d\n", __func__, __LINE__);
return 0;
}
/**
* It actually flash the bitstream on the FGPA
*/
static int svec_close(struct inode *inode, struct file *f)
{
pr_info("%s:%d\n", __func__, __LINE__);
return 0;
}
/**
* It creates a local copy of the user buffer
*/
static ssize_t svec_write(struct file *f, const char __user *buf,
size_t count, loff_t *offp)
{
pr_info("%s:%d\n", __func__, __LINE__);
if (!count)
return -EINVAL;
return count;
}
/**
* Char device operation to provide bitstream
*/
static const struct file_operations svec_fops = {
.owner = THIS_MODULE,
.open = svec_open,
.release = svec_close,
.write = svec_write,
};
static void svec_release(struct device *dev)
{
struct svec_dev *svec = to_svec_dev(dev);
svec_minor_put(MINOR(dev->devt));
kfree(svec);
}
/**
* It initialize a new SVEC instance
......@@ -42,11 +126,14 @@ static int svec_probe(struct device *dev, unsigned int ndev)
svec = kzalloc(sizeof(struct svec_dev), GFP_KERNEL);
if (!svec) {
dev_err(dev, "Cannot allocate memory for svec card struct\n");
return -ENOMEM;
goto err;
}
dev_set_name(&svec->dev, "svec.%d", vdev->slot);
svec->dev.class = svec_class;
svec->dev.devt = basedev + svec_minor_get();
svec->dev.parent = &vdev->dev;
svec->dev.release = svec_release;
dev_set_drvdata(&vdev->dev, svec);
err = device_register(&svec->dev);
......@@ -56,7 +143,10 @@ static int svec_probe(struct device *dev, unsigned int ndev)
return 0;
err_dev_reg:
svec_minor_put(MINOR(svec->dev.devt));
kfree(svec);
err:
dev_err(dev, "Failed to register SVEC device\n");
return err;
}
......@@ -66,7 +156,6 @@ static int svec_remove(struct device *pdev, unsigned int ndev)
struct svec_dev *svec = dev_get_drvdata(pdev);
device_unregister(&svec->dev);
kfree(svec);
return 0;
}
......@@ -99,12 +188,45 @@ static struct vme_driver svec_driver = {
static int __init svec_init(void)
{
return vme_register_driver(&svec_driver, 0);
int err = 0;
svec_class = class_create(THIS_MODULE, "svec");
if (IS_ERR_OR_NULL(svec_class)) {
err = PTR_ERR(svec_class);
goto err_cls;
}
/* Allocate a char device region for devices, CPUs and slots */
err = alloc_chrdev_region(&basedev, 0, SVEC_MINOR_MAX, "svec");
if (err)
goto err_chrdev_alloc;
cdev_init(&svec_cdev, &svec_fops);
svec_cdev.owner = THIS_MODULE;
err = cdev_add(&svec_cdev, basedev, SVEC_MINOR_MAX);
if (err)
goto err_cdev_add;
err = vme_register_driver(&svec_driver, 0);
if (err)
goto err_drv_reg;
return 0;
err_drv_reg:
cdev_del(&svec_cdev);
err_cdev_add:
unregister_chrdev_region(basedev, SVEC_MINOR_MAX);
err_chrdev_alloc:
class_destroy(svec_class);
err_cls:
return err;
}
static void __exit svec_exit(void)
{
vme_unregister_driver(&svec_driver);
cdev_del(&svec_cdev);
unregister_chrdev_region(basedev, SVEC_MINOR_MAX);
class_destroy(svec_class);
}
module_init(svec_init);
......
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