106 lines
2.3 KiB
C
106 lines
2.3 KiB
C
/*********************************************
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* Benjamin Krill <ben@codiert.org>
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*********************************************/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include "fpgafs.h"
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#define FPGAFS_MAX_LLDRV 3
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static struct fpgafs_lldrv *lldrv[FPGAFS_MAX_LLDRV];
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static struct fpgafs_lldrv *lldrv_cur;
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static int lldrv_count = 0x0;
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static DEFINE_SPINLOCK(fpgafs_lldrv_lock);
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ssize_t fpgafs_send_data(struct file *file, char __user *buf,
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size_t len, loff_t *pos)
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{
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return (lldrv_cur) ? lldrv_cur->send(buf, len) : -EBUSY;
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}
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EXPORT_SYMBOL_GPL(fpgafs_send_data);
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ssize_t fpgafs_recv_data(struct file *file, char __user *buf,
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size_t len, loff_t *pos)
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{
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return (lldrv_cur) ? lldrv_cur->recv(buf, len) : -EBUSY;
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}
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EXPORT_SYMBOL_GPL(fpgafs_recv_data);
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int fpgafs_write_load(char *buf, int len)
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{
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return (lldrv_cur) ? lldrv_cur->write_load(buf, len) : -EBUSY;
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}
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EXPORT_SYMBOL_GPL(fpgafs_write_load);
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int fpgafs_read_load(char *buf, int len)
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{
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return (lldrv_cur) ? lldrv_cur->read_load(buf, len) : -EBUSY;
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}
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EXPORT_SYMBOL_GPL(fpgafs_read_load);
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/* low level un-/register functions */
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int fpgafs_register_lldrv(struct fpgafs_lldrv *drv)
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{
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unsigned long flags;
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int i;
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spin_lock_irqsave(&fpgafs_lldrv_lock, flags);
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if (lldrv_count == FPGAFS_MAX_LLDRV)
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return -EBUSY;
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/* find free space */
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for(i=0; i < FPGAFS_MAX_LLDRV; i++)
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if (lldrv[lldrv_count] == NULL) {
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lldrv[lldrv_count] = drv;
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break;
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}
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if (lldrv[lldrv_count]->init)
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lldrv[lldrv_count]->init();
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lldrv_cur = lldrv[lldrv_count];
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lldrv_count++;
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spin_unlock_irqrestore(&fpgafs_lldrv_lock, flags);
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return 0;
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}
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EXPORT_SYMBOL_GPL(fpgafs_register_lldrv);
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int fpgafs_unregister_lldrv(struct fpgafs_lldrv *drv)
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{
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unsigned long flags;
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int i,k;
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spin_lock_irqsave(&fpgafs_lldrv_lock, flags);
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for(i=0; i < FPGAFS_MAX_LLDRV; i++) {
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if (lldrv[i] == drv) {
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/* call the exit function */
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if (lldrv[i]->exit)
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lldrv[i]->exit();
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lldrv[i] = NULL;
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/* if current, search another low level driver */
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if (lldrv_cur == drv) {
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lldrv_cur = NULL;
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for(k=0; k < FPGAFS_MAX_LLDRV; k++)
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if (lldrv[k]) {
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lldrv_cur = lldrv[k];
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break;
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}
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}
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break;
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}
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}
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lldrv_count--;
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spin_unlock_irqrestore(&fpgafs_lldrv_lock, flags);
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return 0;
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}
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EXPORT_SYMBOL_GPL(fpgafs_unregister_lldrv);
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