From 5ba35bd8f9a4fa6b92ef707826c47a1466ece460 Mon Sep 17 00:00:00 2001 From: Pete Zaitcev Date: Fri, 16 Dec 2005 00:39:36 -0800 Subject: [PATCH] [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: Pete Zaitcev Signed-off-by: Greg Kroah-Hartman --- drivers/usb/storage/libusual.c | 53 +++++++++++++++++----------------- 1 file changed, 27 insertions(+), 26 deletions(-) diff --git a/drivers/usb/storage/libusual.c b/drivers/usb/storage/libusual.c index 61f73d8a2c0..2680c69a241 100644 --- a/drivers/usb/storage/libusual.c +++ b/drivers/usb/storage/libusual.c @@ -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"); -- 2.41.1