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

drivers/usb/storage/libusual.c

+27 −26
Original line number Diff line number Diff line
@@ -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 {

	len = strlen(bias_s);

	if (len == 0)

		return -EDOM;

	if (bias_s[len-1] == '\n')

		--len;



	for (i = 1; i < 3; i++) {

			if (strcmp(bias_s, bias_names[i]) == 0) {

		if (strncmp(bias_s, bias_names[i], len) == 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]);

		}

	if (bias_n == 0)

		return -EINVAL;



	atomic_set(&usu_bias, bias_n);

	return 0;

}

	return bias_n;



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");