My requirement I need to print buffer in tty driver level before coming to user level. For that,
I am trying to print the buffer coming from /dev/ttyS5 in UART driver level(I am not looking in user level). For that I dig into code I found below is the read sequence for TTY driver.
tty_read <-- ldisc.read <-- tty_flipbuffer_push <-- interrupt <-- Hardware
I added below code in my tty_read API at the end
static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
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"
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if((imajor(inode) == 245) && (iminor(inode) == 5)) { // I am filtering messages using major and minor number
printk("Test print\n"); //OK
printk("Buffer %c\n", buf[0]); // Kernel panic (segfault)
}
}
Can you help me how to figure out buffer contents in driver level?
I am using latest SDK AM335X.
