diff options
Diffstat (limited to 'drivers/fsi')
| -rw-r--r-- | drivers/fsi/fsi-scom.c | 130 |
1 files changed, 80 insertions, 50 deletions
diff --git a/drivers/fsi/fsi-scom.c b/drivers/fsi/fsi-scom.c index 39c74351f1bf..0f303a700f69 100644 --- a/drivers/fsi/fsi-scom.c +++ b/drivers/fsi/fsi-scom.c @@ -20,9 +20,8 @@ #include <linux/fs.h> #include <linux/uaccess.h> #include <linux/slab.h> -#include <linux/miscdevice.h> +#include <linux/cdev.h> #include <linux/list.h> -#include <linux/idr.h> #include <uapi/linux/fsi.h> @@ -77,18 +76,12 @@ struct scom_device { struct list_head link; struct fsi_device *fsi_dev; - struct miscdevice mdev; + struct device dev; + struct cdev cdev; struct mutex lock; - char name[32]; - int idx; + bool dead; }; -#define to_scom_dev(x) container_of((x), struct scom_device, mdev) - -static struct list_head scom_devices; - -static DEFINE_IDA(scom_ida); - static int __put_scom(struct scom_device *scom_dev, uint64_t value, uint32_t addr, uint32_t *status) { @@ -374,9 +367,7 @@ static int get_scom(struct scom_device *scom, uint64_t *value, static ssize_t scom_read(struct file *filep, char __user *buf, size_t len, loff_t *offset) { - struct miscdevice *mdev = - (struct miscdevice *)filep->private_data; - struct scom_device *scom = to_scom_dev(mdev); + struct scom_device *scom = filep->private_data; struct device *dev = &scom->fsi_dev->dev; uint64_t val; int rc; @@ -385,7 +376,10 @@ static ssize_t scom_read(struct file *filep, char __user *buf, size_t len, return -EINVAL; mutex_lock(&scom->lock); - rc = get_scom(scom, &val, *offset); + if (scom->dead) + rc = -ENODEV; + else + rc = get_scom(scom, &val, *offset); mutex_unlock(&scom->lock); if (rc) { dev_dbg(dev, "get_scom fail:%d\n", rc); @@ -403,8 +397,7 @@ static ssize_t scom_write(struct file *filep, const char __user *buf, size_t len, loff_t *offset) { int rc; - struct miscdevice *mdev = filep->private_data; - struct scom_device *scom = to_scom_dev(mdev); + struct scom_device *scom = filep->private_data; struct device *dev = &scom->fsi_dev->dev; uint64_t val; @@ -418,7 +411,10 @@ static ssize_t scom_write(struct file *filep, const char __user *buf, } mutex_lock(&scom->lock); - rc = put_scom(scom, val, *offset); + if (scom->dead) + rc = -ENODEV; + else + rc = put_scom(scom, val, *offset); mutex_unlock(&scom->lock); if (rc) { dev_dbg(dev, "put_scom failed with:%d\n", rc); @@ -532,12 +528,15 @@ static int scom_check(struct scom_device *scom, void __user *argp) static long scom_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - struct miscdevice *mdev = file->private_data; - struct scom_device *scom = to_scom_dev(mdev); + struct scom_device *scom = file->private_data; void __user *argp = (void __user *)arg; int rc = -ENOTTY; mutex_lock(&scom->lock); + if (scom->dead) { + mutex_unlock(&scom->lock); + return -ENODEV; + } switch(cmd) { case FSI_SCOM_CHECK: rc = scom_check(scom, argp); @@ -556,48 +555,88 @@ static long scom_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return rc; } +static int scom_open(struct inode *inode, struct file *file) +{ + struct scom_device *scom = container_of(inode->i_cdev, struct scom_device, cdev); + + file->private_data = scom; + + return 0; +} + static const struct file_operations scom_fops = { .owner = THIS_MODULE, + .open = scom_open, .llseek = scom_llseek, .read = scom_read, .write = scom_write, .unlocked_ioctl = scom_ioctl, }; +static void scom_free(struct device *dev) +{ + struct scom_device *scom = container_of(dev, struct scom_device, dev); + + put_device(&scom->fsi_dev->dev); + kfree(scom); +} + static int scom_probe(struct device *dev) { struct fsi_device *fsi_dev = to_fsi_dev(dev); struct scom_device *scom; + int rc, didx; - scom = devm_kzalloc(dev, sizeof(*scom), GFP_KERNEL); + scom = kzalloc(sizeof(*scom), GFP_KERNEL); if (!scom) return -ENOMEM; - + dev_set_drvdata(dev, scom); mutex_init(&scom->lock); - scom->idx = ida_simple_get(&scom_ida, 1, INT_MAX, GFP_KERNEL); - snprintf(scom->name, sizeof(scom->name), "scom%d", scom->idx); - scom->fsi_dev = fsi_dev; - scom->mdev.minor = MISC_DYNAMIC_MINOR; - scom->mdev.fops = &scom_fops; - scom->mdev.name = scom->name; - scom->mdev.parent = dev; - list_add(&scom->link, &scom_devices); - - return misc_register(&scom->mdev); + + /* Grab a reference to the device (parent of our cdev), we'll drop it later */ + if (!get_device(dev)) { + kfree(scom); + return -ENODEV; + } + + /* Create chardev for userspace access */ + scom->dev.type = &fsi_cdev_type; + scom->dev.parent = dev; + scom->dev.release = scom_free; + device_initialize(&scom->dev); + + /* Allocate a minor in the FSI space */ + rc = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx); + if (rc) + goto err; + + dev_set_name(&scom->dev, "scom%d", didx); + cdev_init(&scom->cdev, &scom_fops); + rc = cdev_device_add(&scom->cdev, &scom->dev); + if (rc) { + dev_err(dev, "Error %d creating char device %s\n", + rc, dev_name(&scom->dev)); + goto err_free_minor; + } + + return 0; + err_free_minor: + fsi_free_minor(scom->dev.devt); + err: + put_device(&scom->dev); + return rc; } static int scom_remove(struct device *dev) { - struct scom_device *scom, *scom_tmp; - struct fsi_device *fsi_dev = to_fsi_dev(dev); + struct scom_device *scom = dev_get_drvdata(dev); - list_for_each_entry_safe(scom, scom_tmp, &scom_devices, link) { - if (scom->fsi_dev == fsi_dev) { - list_del(&scom->link); - ida_simple_remove(&scom_ida, scom->idx); - misc_deregister(&scom->mdev); - } - } + mutex_lock(&scom->lock); + scom->dead = true; + mutex_unlock(&scom->lock); + cdev_device_del(&scom->cdev, &scom->dev); + fsi_free_minor(scom->dev.devt); + put_device(&scom->dev); return 0; } @@ -622,20 +661,11 @@ static struct fsi_driver scom_drv = { static int scom_init(void) { - INIT_LIST_HEAD(&scom_devices); return fsi_driver_register(&scom_drv); } static void scom_exit(void) { - struct list_head *pos; - struct scom_device *scom; - - list_for_each(pos, &scom_devices) { - scom = list_entry(pos, struct scom_device, link); - misc_deregister(&scom->mdev); - devm_kfree(&scom->fsi_dev->dev, scom); - } fsi_driver_unregister(&scom_drv); } |