Commit 5ba35bd8 authored by Pete Zaitcev's avatar Pete Zaitcev Committed by Greg Kroah-Hartman
Browse files

[PATCH] USB: make bias writeable in libusual



Make the bias parameter writeable. Writing the parameter does not trigger
a rebind of currently attached storage devices.
Signed-off-by: default avatarPete Zaitcev <zaitcev@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent a00828e9
......@@ -24,10 +24,9 @@ static DEFINE_SPINLOCK(usu_lock);
/*
*/
#define USB_US_DEFAULT_BIAS USB_US_TYPE_STOR
static atomic_t usu_bias = ATOMIC_INIT(USB_US_DEFAULT_BIAS);
#define BIAS_NAME_SIZE (sizeof("usb-storage"))
static char bias[BIAS_NAME_SIZE];
static int usb_usual_bias;
static const char *bias_names[3] = { "none", "usb-storage", "ub" };
static DECLARE_MUTEX_LOCKED(usu_init_notify);
......@@ -35,7 +34,6 @@ static DECLARE_COMPLETION(usu_end_notify);
static atomic_t total_threads = ATOMIC_INIT(0);
static int usu_probe_thread(void *arg);
static int parse_bias(const char *bias_s);
/*
* The table.
......@@ -107,7 +105,7 @@ int usb_usual_check_type(const struct usb_device_id *id, int caller_type)
if (id_type == caller_type)
return 0;
/* Drivers grab devices biased to them */
if (id_type == USB_US_TYPE_NONE && caller_type == usb_usual_bias)
if (id_type == USB_US_TYPE_NONE && caller_type == atomic_read(&usu_bias))
return 0;
return -ENODEV;
}
......@@ -124,7 +122,7 @@ static int usu_probe(struct usb_interface *intf,
type = USB_US_TYPE(id->driver_info);
if (type == 0)
type = usb_usual_bias;
type = atomic_read(&usu_bias);
spin_lock_irqsave(&usu_lock, flags);
if ((stat[type].fls & (USU_MOD_FL_THREAD|USU_MOD_FL_PRESENT)) != 0) {
......@@ -206,9 +204,6 @@ static int __init usb_usual_init(void)
{
int rc;
bias[BIAS_NAME_SIZE-1] = 0;
usb_usual_bias = parse_bias(bias);
rc = usb_register(&usu_driver);
up(&usu_init_notify);
return rc;
......@@ -231,36 +226,42 @@ static void __exit usb_usual_exit(void)
/*
* Validate and accept the bias parameter.
* Maybe make an sysfs method later. XXX
*/
static int parse_bias(const char *bias_s)
static int usu_set_bias(const char *bias_s, struct kernel_param *kp)
{
int i;
int len;
int bias_n = 0;
if (bias_s[0] == 0 || bias_s[0] == ' ') {
bias_n = USB_US_DEFAULT_BIAS;
} else {
for (i = 1; i < 3; i++) {
if (strcmp(bias_s, bias_names[i]) == 0) {
bias_n = i;
break;
}
}
if (bias_n == 0) {
bias_n = USB_US_DEFAULT_BIAS;
printk(KERN_INFO
"libusual: unknown bias \"%s\", using \"%s\"\n",
bias_s, bias_names[bias_n]);
len = strlen(bias_s);
if (len == 0)
return -EDOM;
if (bias_s[len-1] == '\n')
--len;
for (i = 1; i < 3; i++) {
if (strncmp(bias_s, bias_names[i], len) == 0) {
bias_n = i;
break;
}
}
return bias_n;
if (bias_n == 0)
return -EINVAL;
atomic_set(&usu_bias, bias_n);
return 0;
}
static int usu_get_bias(char *buffer, struct kernel_param *kp)
{
return strlen(strcpy(buffer, bias_names[atomic_read(&usu_bias)]));
}
module_init(usb_usual_init);
module_exit(usb_usual_exit);
module_param_string(bias, bias, BIAS_NAME_SIZE, S_IRUGO|S_IWUSR);
module_param_call(bias, usu_set_bias, usu_get_bias, NULL, S_IRUGO|S_IWUSR);
__MODULE_PARM_TYPE(bias, "string");
MODULE_PARM_DESC(bias, "Bias to usb-storage or ub");
MODULE_LICENSE("GPL");
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