spi.c

spi设备uclinux驱动源代码

/****************************************Copyright (c)**************************************************
**                               Guangzou ZLG-MCU Development Co.,LTD.
**                                     graduate school
**                                 http://www.zlgmcu.com
**
**--------------File Info-------------------------------------------------------------------------------
** File name:           spi.c
** Last modified Date:  2005-04-29
** Last Version:        1.0
** Descriptions:        This is a Kernel module for uClinux 2.4.x .
**                      This module let uClinux 2.4.x can use spi. 
**------------------------------------------------------------------------------------------------------
** Created by:          Chenmingji
** Created date:        2005-04-29
** Version:             1.0
** Descriptions:        The original version
**
**------------------------------------------------------------------------------------------------------
** Modified by:
** Modified date:
** Version:
** Descriptions:
**

********************************************************************************************************/
#define IN_SPI
#include "config.h"

/********************************************************************************************************
              function announce
********************************************************************************************************/

#if 0
static loff_t spi_llseek(struct file *filp, loff_t off, int whence);
#endif

static ssize_t spi_write(struct file *filp, const char *buf, size_t count, loff_t *f_pos);
static ssize_t spi_read(struct file *filp, char *buf, size_t count, loff_t *f_pos);
static int spi_open(struct inode *inode, struct file *filp);
static int spi_release(struct inode *inode, struct file *filp); 
static int spi_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
                     unsigned long param);
int  spi_init(void);
void spi_cleanup(void);

/********************************************************************************************************
              define announce
********************************************************************************************************/
#define MAJOR_NR major

module_init(spi_init);
module_exit(spi_cleanup);

MODULE_PARM(major, "i");

MODULE_LICENSE("Proprietary");
MODULE_DESCRIPTION("Guangzou ZLG-MCU Development Co.,LTD.\ngraduate school\nhttp://www.zlgmcu.com");
MODULE_SUPPORTED_DEVICE("uClinux2.4.x LPC2200 spi");
MODULE_AUTHOR("chenmingji");

/*********************************************************************************************************
**                  "全局和静态变量在这里定义"         
**        global variables and static variables define here
********************************************************************************************************/
typedef struct Spi_Dev
{
    u32                 BaseAddr;
    unsigned int        usage;      /* device using count */
    struct semaphore    sem;        /* mutual exclusion semaphore     */
} Spi_Dev;

static int major = SPI_MAJOR_NR;
static u32 PinSel0Save, PinSel1Save;

Spi_Dev SpiDevices[MAX_SPI];

/********************************************************************************************************/

static struct file_operations spi_fops =        /* driver info  */
{
    owner:      THIS_MODULE,
#if 0
    llseek:     spi_llseek,
#endif
    write:      spi_write,
    read:       spi_read,
    ioctl:      spi_ioctl,
    open:       spi_open,
    release:    spi_release,
};


#if 0
/*********************************************************************************************************
** Function name: spi_llseek
** Descriptions:  move read and write point
** Input: filp:   pointer of file
**        off:    ofset
**        whence: move mode
**                0: seek set
**                1: seek file' current point
**                2: seek file' end
** Output :      new point
** Created by:   Chenmingji
** Created Date: 2005-4-29
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
        static loff_t spi_llseek(struct file *filp, loff_t off, int whence)
{
    return 0;
}
#endif

/*********************************************************************************************************
** Function name: spi_read
** Descriptions:  read device
** Input: filp:   pointer of file
**        buf:    buf for save data
**        count:  size for read
**        f_pos:  *f_pos = read point
** Output : read size    
** Created by:   Chenmingji
** Created Date: 2005-4-29
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
        static ssize_t spi_read(struct file *filp, char *buf, size_t count,
                           loff_t *f_pos)
{
    size_t i;
    unsigned int temp;
    Spi_Dev *dep;
        
    if (!access_ok(VERIFY_WRITE, (void *)buf, _IOC_SIZE(cmd)))
    {
        return -EFAULT;
    }

    dep = filp->private_data;
    
    i = count;
    do
    {
        outl(0, dep->BaseAddr + S0PDR - S0PCR);
        while (1)
        {
            temp = inl(dep->BaseAddr + S0PSR - S0PCR);
            if ((temp & (1 << 7)) != 0)
            {
                break;
            }
            if (temp != 0)
            {
                goto end;
            }
        }
        temp = inl(dep->BaseAddr + S0PDR - S0PCR);
        put_user(temp, (u8 *)buf);
        buf++;
    } while (--i != 0);
end:
    return count - i;
}

/*********************************************************************************************************
** Function name: spi_write
** Descriptions:  write device
** Input: filp:   pointer of file
**        buf:    buf to write data
**        count:  size for read
**        f_pos:  *f_pos = read point
** Output : write size    
** Created by:   Chenmingji
** Created Date: 2005-4-29
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
        static ssize_t spi_write(struct file *filp, const char *buf, size_t count,
                            loff_t *f_pos)
{
    size_t i;
    unsigned int temp;
    Spi_Dev *dep;
        
    if (!access_ok(VERIFY_READ, (void *)buf, count))
    {
          return -EFAULT;
    }

    dep = filp->private_data;
    
    i = count;
    do
    {
        get_user(temp, (u8 *)buf);
        outl(temp, dep->BaseAddr + S0PDR - S0PCR);
        while (1)
        {
            temp = inl(dep->BaseAddr + S0PSR - S0PCR);
            if ((temp & (1 << 7)) != 0)
            {
                break;
            }
            if (temp != 0)
            {
                goto end;
            }
        }
        inl(dep->BaseAddr + S0PDR - S0PCR);
        buf++;
    } while (--i != 0);
end:
    return count - i;
}
                
/*********************************************************************************************************
** Function name: spi_open
** Descriptions:  open device
** Input:inode:   information of device
**       filp:    pointer of file
** Output 0:      OK
**        other:  not OK
** Created by:    Chenmingji
** Created Date:  2005-4-29
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
        static int spi_open(struct inode *inode, struct file *filp)
{
    unsigned long flag;
    int num;
    u32 temp;

    num = MINOR(inode->i_rdev);
    if (num >= MAX_SPI)
    {
        return -ENODEV;
    }

    if (SpiDevices[num].usage == 0)
    {
        local_irq_save(flag);
        if (num == 0)
        {
            temp = inl(PINSEL0);
            PinSel0Save =  temp & (0xff << 8);