PWM驱动问题

做好蜂鸣器驱动，编译都没问题，启动系统后打印如下信息（截取了其中的一部分）：
TQ2440/SKY2440 LEDS, (c) 2008,2009 www.embedsky.net
EmbedSky-leds initialized
TQ2440/SKY2440 Beep, (c) 2008,2009 www.embedsky.net
EmbedSky-Beep initialized
lp: driver loaded but no devices found
ppdev: user-space parallel port driver
Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
s3c2440-uart.0: s3c2410_serial0 at MMIO 0x50000000 (irq = 70) is a S3C2440
s3c2440-uart.1: s3c2410_serial1 at MMIO 0x50004000 (irq = 73) is a S3C2440
s3c2440-uart.2: s3c2410_serial2 at MMIO 0x50008000 (irq = 76) is a S3C2440
loop: module loaded
Driver 'sd' needs updating - please use bus_type methods
....................
Please press Enter to activate this console.
[root@EmbedSky /]# ls /dev/EmbedSky-Beep
/dev/EmbedSky-Beep
[root@EmbedSky /]# ls /dev/EmbedSky-leds
/dev/EmbedSky-leds
[root@EmbedSky /]# beep
_
然后就停留在这里，输入数字蜂鸣器也没有响声

是天嵌的源码