ADC

1
ADC

• ??? MCSL ???

2
???? ??????

• ????? ?????? ????? ??.
• ??????? ??? System Call? ??? ???? ?? ??.
• ???? ????? ????? ???? ???? ??. ??? ? ?? ??? ????
  ??? ?? ??? ??? ??? ????.
• ???? ????? ??????? ???? ??? ???? System Call? ???
  ???? ??

3
2.6 Kernel

• system call? ?? ??? ???? ??
• Processor? App? ???? ?? system call ??? ???
• ?? ???? ?? ????.
• ?? ???? device??? data ??? ??
• ?? ???? process ? ?? ??? ?? wait queue? ???
• ??? process? ??

4
2.6 Kernel Device Driver

• - ????? ??? ????? ?? ???? ???? ?????
• ????? ??? ?? ??? ???? ?? ?????.
• - ??? 2.6????? kobject?? ???? ?? ??? ???.
• ??? ??? ?? ??? ??? ????? ???? ?? ????? ?????
  ???? ?? ?? ????? ?? ???? ??.
• ADC? ?? ?? ?? ? ??? platform_bus_type ?? ??? ???
  ?? ?? ??? ????? ???? ????.
• (?? ??? ??? ????(Major)??? Device ??(Minor)? ??
  ??)

5
ADC ???? ???? ??

• ADC ???? ????? ?? ??? ??? ??.
• platform_driver ??
• Probe?? ?? (ADC ?? ???? ???)
• Probe ???? ?? ???? ?? / ??(Clock, platform_data)
• Miscdevice ?? (Miscdevice name? ??
  platform_driver ??)
• file_operations ??(.fops name)
• file_operations?? ??? ?? ???? ??
• User App?? ??? ???? System Call? ??

6
????? ? ???

• Struct device_driver
• Struct platform_device driver
• Struct miscdevice
• Struct file_operations

7
struct device_driver ???

• include ltlinux/device.hgt
• ?? ?? ??? ????? ??? ??? ??
• struct device_driver
• const char name //???? ????? ??(??)
• struct bus_type bus //?? ??(??)
• struct kobject kobj //??? ??
• struct module owner // ?? THIS_MODULE
• int (probe) (struct device dev) // ??? ??
• int (remove) (struct device dev) // ???? ??
  ??
• int (suspend) (struct device dev, pm_message_t
  state, u32 level)
• //???? (??)
• int (resume) (struct device dev, u32 level)
  //???? off (??)
• . ??

8
Struct platform_device

• include ltplatform_devicegt
• struct platform_device
• const char name
• //platform_driver? ??? ??? ??? ??.
• int id
• struct device dev
• u32 num_resources
• struct resource resource
• struct platform_device_id id_entry
• / arch specific additions /
• struct pdev_archdata archdata

9
Miscdevice ???

• include ltlinux/miscdevice.hgt
• struct miscdevice
• int minor //Device driver minor number
• (???? ??? ??? ???? ??)
• const char name //device file Name
• const struct file_operations fops
• // ?? ??? ? ? ??? ?? ??
• ??

10
struct file_operations ???

• struct file_operations struct module
  owner //?? THIS_MODULEssize_t (read) (struct
  file , char __user , size_t, loff_t )ssize_t
  (write) (struct file , const char __user ,
  size_t, loff_t )int (ioctl) (struct inode ,
  struct file , unsigned int,
• unsigned long)
• // Read? Write??? ???? ??? ??? ??
• int (open) (struct inode , struct file )
• // ?? ?????? ????? ?? ???? ??(??)int (release)
  (struct inode , struct file )
• // ??
• . ??

11
ADC Platform_driver

• static struct platform_driver s3c_adc_driver
• .probe s3c_adc_probe,
• .remove s3c_adc_remove,
• .suspend s3c_adc_suspend,
• .resume s3c_adc_resume,
• .driver
• .owner THIS_MODULE,
• .name "s3c-adc",
• ,

12
Device Dirver Init

• ?? ???? ?????? ??? Init ??? ?? ????.
• int __init s3c_adc_init(void)
• printk(banner)
• return platform_driver_register(s3c_adc_driver)
  
• // Platform_driver ??
• module_init(s3c_adc_init)

13
Probe ??? ???? ??!

• platform_driver_register() ??? call? ???
  xxxx_probe()??? call? ??? ?????? ??? ??
• ?? platform_add_devices() ??? ??? platform
  device?
• ??? ?? ??? ??.
• ?? platform_add_devices ? platform_driver_registe
  r??
• .name? ?????? ?? ?? ??.

14
Probe ??? ???? ??!

• /kernel/arch/arm/plat-s5p/devs.c
• static struct resource s3c_adc_resource
• 0
• .start S3C_PA_ADC, // ADC
  Register??
• .end S3C_PA_ADC SZ_4K - 1,
  // ?? ??? ?
• .flags IORESOURCE_MEM, //
  resource type ,
• include ltmach/map.hgt
• define S3C_PA_ADC S3C_ADDR(0xE1700000) // ??? ??

15
Probe ??? ???? ??!

• struct platform_device s3c_device_adc
• .name "s3c-adc",
• //platform_driver? ??? ??? ??.
• .id -1,
• // ?? ?? ??? ????? ???? id? ??
• .num_resources ARRAY_SIZE(s3c_adc_res
  ource),
• //??? ??? ?
• .resource s3c_adc_resource, ???
  ??? ?? ??

16
Probe ??? ???? ??!

• /kernel/arch/arm/mach-s5pv210/mach-mango210.c
• static struct platform_device mango210_devices
  __initdata
• s3c_device_adc, // platform_device name ??
• static void __init mango210_machine_init(void)
• s3c_adc_set_platdata(s3c_adc_platform)
• platform_add_devices(mango210_devices,
  ARRAY_SIZE(mango210_devices)) // ??? ??
• ???? ????? Platform ???? ????? ??? ??
• Probe??? ????.

17
ADC Probe

• ??? ???? ???? Probe??? ?? ??? ??? ??
• static int __init s3c_adc_probe(struct
  platform_device pdev)
• struct resource res
• struct device dev
• res platform_get_resource(pdev,
  IORESOURCE_MEM, 0)
• //???(????? ??? ?? ??) ????
• dev pdev-gtdev
• //// pdev ?? ??? ????? ???? dev ? ???? cast ???.
  ??? pdev? dev? ???? ??
• ltplatform_device.hgt
• extern struct resource platform_get_resource
• (struct platform_device , //??? ???? ??
• unsigned int, // flags
• unsigned int)

18
ADC Probe

• static struct resource adc_mem // Global define
• static void __iomem base_addr // Global define
• ////static void __iomem ??? ??? ?? ??
• Writel, readl ?? core register?? ??? ???? ??????
  ??? ???? ????.
• size (res-gtend - res-gtstart) 1 // ??? ??? ??
• base_addr ioremap(res-gtstart, size) // ?? ???
  ?? ??
• adc_clock clk_get(pdev-gtdev, "adc") // ?? ???
  ??
• clk_enable(adc_clock)
• ?? (?? ?? prescaler, delay ?? register init)
• ret misc_register(s3c_adc_miscdev)
  //miscdevice? ??? ??.

19
Miscdevice

• static struct miscdevice s3c_adc_miscdev
• .minor ADC_MINOR,
• .name "adc", //device file name
• .fops s3c_adc_fops,
• Miscdev ??? ??? FileSystem ??? /dev/adc?? ????
  ??? ??? ????. ??? /etc/udev? ????? ??? ????? ??.

20
User App?? ADC Driver ??

• ???? ????? File_operation ???? ??
• Ioctl
• Read
• Open
• ?? ????. ? ??? ??? ?? IOCTL? ADC PORT??
• READ? buffer???? ADC ??? ??
• OPEN? ???? ????? ???? ?????? ?? Call??.

21
?????