EmbLogic » Ritu Bagla https://www.emblogic.com/blog Embedded System and ARM Training Tue, 03 Mar 2020 13:00:06 +0000 en-US hourly 1 http://wordpress.org/?v=3.9.1 toolchain and usb status https://www.emblogic.com/blog/09/toolchain-and-usb-status/ https://www.emblogic.com/blog/09/toolchain-and-usb-status/#comments Sun, 02 Sep 2012 09:20:22 +0000 http://emblogic.org/blog/?p=5132 in toolchain : done binutils,kernel,gcc… now doing glibc…..
in usb driver : done notifier and usb generic….. now doing probe function…

]]> https://www.emblogic.com/blog/09/toolchain-and-usb-status/feed/ 0 facing problem in allocating memory for new quantum after lseek https://www.emblogic.com/blog/04/facing-problem-in-allocating-memory-for-new-quantum-after-lseek/ https://www.emblogic.com/blog/04/facing-problem-in-allocating-memory-for-new-quantum-after-lseek/#comments Mon, 23 Apr 2012 13:10:05 +0000 http://emblogic.org/blog/?p=2449 Continue reading →]]> ssize_t scull_write ( struct file *filp, const char __user *buffer, size_t count , loff_t *offset)
{
struct ScullDev *lsculldev;
struct ScullQset *lscullqset;
int noq, nobsw,start_q,lcount,lv,ret;
int nobtw,noq_f,index,new_pos;
nobtw = count;
index = noq_f = 0;
lcount = noq = nobsw = start_q = lv = ret = 0;

#ifdef DEBUG
printk(KERN_INFO “Begin :%s\n”,__func__);
#endif
lsculldev = filp->private_data;
new_pos = filp->f_pos;
printk(KERN_INFO”value of filep=%d\n”,new_pos);
if(!lsculldev)
{
#ifdef DEBUG
printk(KERN_INFO “No Sculldev\n”);
#endif
goto OUT;
}
if(count size_of_device)
{
#ifdef DEBUG
printk(KERN_INFO “Not Enough Memory\n”);
#endif
goto OUT;
}

lscullqset = scull_follow(lsculldev);
if(!lscullqset)
{
lscullqset =(struct ScullQset *) kmalloc(sizeof(struct ScullQset),GFP_KERNEL);
if(!lscullqset)
{

#ifdef DEBUG
printk(KERN_INFO “Memory Allocation Failed\n”);
#endif
goto OUT;
}

lscullqset->data = kmalloc(sizeof(char*)*qset_size,GFP_KERNEL);

if(!lscullqset->data)
{

#ifdef DEBUG
printk(KERN_INFO “Memory Allocation Failed for qset array\n”);
#endif
goto OUT;
}
}
lsculldev->scullqset = lscullqset;
noq=count / quantum_size;
if(count % quantum_size)
{
noq++;
}
lsculldev->qset = noq;
printk(“noq = %d\n”,noq);
start_q = new_pos / quantum_size;
lv = start_q;
if(w_flag)
{
while(nobsw data[lv])
{
if(lv == start_q)
{
index = new_pos % quantum_size;
lcount = quantum_size – index;
ret = copy_from_user(lscullqset->data[lv]+index,buffer+nobsw,lcount);
#ifdef DEBUG
printk(KERN_INFO “data :%s\n”,(char*)lscullqset->data[lv]);
#endif
nobsw = nobsw + (lcount – ret);
lv++;
}
else
{
{
if(quantum_size count – nobsw)
lcount = count – nobsw;
printk(“ccc\n”);
ret = copy_from_user(lscullqset->data[lv],buffer+nobsw,lcount);
#ifdef DEBUG
printk(KERN_INFO “data :%s\n”,(char*)lscullqset->data[lv]);
#endif
nobsw = nobsw + (lcount – ret);
lv++;
}
printk(“~~~~\n\n”);
}
else
{
printk(“allocating memory for new quantum\n”);
noq_f++;

lscullqset->data[lv] = kmalloc(sizeof(char)*quantum_size,GFP_KERNEL);
if(!lscullqset->data[lv])
{
#ifdef DEBUG
printk(KERN_INFO “Memory Allocation Failed for new quantum\n”);
#endif
return -1;
}
#ifdef DEBUG
printk(KERN_INFO “Memory Allocated for new quantum\n”);
#endif

}

}
}
else
{
for(lv =0; lv data[lv] = kmalloc(sizeof(char)*quantum_size,GFP_KERNEL);
if(!lscullqset->data[lv])
{
#ifdef DEBUG
printk(KERN_INFO “Memory Allocation Failed for qset array\n”);
#endif
goto OUT;
}
}
for(lv=0; lv < noq; lv++)
{
if(quantum_size count – nobsw)
lcount = count – nobsw;
ret = copy_from_user(lscullqset->data[lv],buffer+nobsw,lcount);
#ifdef DEBUG
printk(KERN_INFO “data :%s\n”,(char*)lscullqset->data[lv]);
#endif
nobsw = nobsw + (lcount – ret);
w_flag = 1;
}
}
#ifdef DEBUG
printk(KERN_INFO “End :%s\n”,__func__);
#endif
return nobsw;
OUT:
#ifdef DEBUG
printk(KERN_INFO “End :%s\n”,__func__);
#endif

return -1;
}

]]> https://www.emblogic.com/blog/04/facing-problem-in-allocating-memory-for-new-quantum-after-lseek/feed/ 1 character drivers https://www.emblogic.com/blog/04/character-drivers/ https://www.emblogic.com/blog/04/character-drivers/#comments Mon, 16 Apr 2012 18:10:36 +0000 http://emblogic.org/blog/?p=2447 reading/writing for mutiple quantum , reading/writing for different application , trimming , mutiple threaded application without using semaphore, lssek for linear quantum had done

]]> https://www.emblogic.com/blog/04/character-drivers/feed/ 0 LKM https://www.emblogic.com/blog/04/lkm-3/ https://www.emblogic.com/blog/04/lkm-3/#comments Tue, 03 Apr 2012 06:31:03 +0000 http://emblogic.org/blog/?p=2357 done four steps of initialization function………

]]> https://www.emblogic.com/blog/04/lkm-3/feed/ 0 drivers https://www.emblogic.com/blog/03/drivers-3/ https://www.emblogic.com/blog/03/drivers-3/#comments Thu, 29 Mar 2012 13:47:55 +0000 http://emblogic.org/blog/?p=2292 implemented 1st lkm….
and chatting on 2 pc using inet….multiple client server using UNIX ….. and threads….

]]> https://www.emblogic.com/blog/03/drivers-3/feed/ 0 Implementing ipcs https://www.emblogic.com/blog/03/implementing-ipcs/ https://www.emblogic.com/blog/03/implementing-ipcs/#comments Wed, 28 Mar 2012 13:57:44 +0000 http://emblogic.org/blog/?p=2274 done single client server for socket (inet and unix)……..facing problem in multiple clients…. done 2way chatting using socket and msg queue……now implementing threads…….

]]> https://www.emblogic.com/blog/03/implementing-ipcs/feed/ 0