static int parse_slot_config()

in eisa_enumerator.c [312:423]

• 86 lines of code
• 18 McCabe index (conditional complexity)

static int parse_slot_config(int slot,
			     const unsigned char *buf,
			     struct eeprom_eisa_slot_info *es, 
			     struct resource *io_parent,
			     struct resource *mem_parent)
{
	int res=0;
	int function_len;
	unsigned int pos=0;
	unsigned int maxlen;
	int num_func=0;
	u_int8_t flags;
	int p0;
	
	char *board;
	int id_string_used=0;
	
	if (NULL == (board = kmalloc(8, GFP_KERNEL))) {
		return -1;
	}
	print_eisa_id(board, es->eisa_slot_id);
	printk(KERN_INFO "EISA slot %d: %s %s ", 
	       slot, board, es->flags&HPEE_FLAG_BOARD_IS_ISA ? "ISA" : "EISA");
	
	maxlen = es->config_data_length < HPEE_MAX_LENGTH ?
			 es->config_data_length : HPEE_MAX_LENGTH;
	while ((pos < maxlen) && (num_func <= es->num_functions)) {
		pos+=configure_function(buf+pos, &function_len); 
		
		if (!function_len) {
			break;
		}
		num_func++;
		p0 = pos;
		pos += configure_choise(buf+pos, &flags);

		if (flags & HPEE_FUNCTION_INFO_F_DISABLED) {
			/* function disabled, skip silently */
			pos = p0 + function_len;
			continue;
		}
		if (flags & HPEE_FUNCTION_INFO_CFG_FREE_FORM) {
			/* I have no idea how to handle this */
			printk("function %d have free-form configuration, skipping ",
				num_func);
			pos = p0 + function_len;
			continue;
		}

		/* the ordering of the sections need
		 * more investigation.
		 * Currently I think that memory comaed before IRQ
		 * I assume the order is LSB to MSB in the 
		 * info flags 
		 * eg type, memory, irq, dma, port, HPEE_PORT_init 
		 */

		if (flags & HPEE_FUNCTION_INFO_HAVE_TYPE) {
			pos += configure_type_string(buf+pos);
		}
		
		if (flags & HPEE_FUNCTION_INFO_HAVE_MEMORY) {
			id_string_used=1;
			pos += configure_memory(buf+pos, mem_parent, board);
		} 
		
		if (flags & HPEE_FUNCTION_INFO_HAVE_IRQ) {
			pos += configure_irq(buf+pos);
		} 
		
		if (flags & HPEE_FUNCTION_INFO_HAVE_DMA) {
			pos += configure_dma(buf+pos);
		} 
		
		if (flags & HPEE_FUNCTION_INFO_HAVE_PORT) {
			id_string_used=1;
			pos += configure_port(buf+pos, io_parent, board);
		} 
		
		if (flags &  HPEE_FUNCTION_INFO_HAVE_PORT_INIT) {
			pos += configure_port_init(buf+pos);
		}
		
		if (p0 + function_len < pos) {
			printk(KERN_ERR "eisa_enumerator: function %d length mis-match "
			       "got %d, expected %d\n",
			       num_func, pos-p0, function_len);
			res=-1;
			break;
		}
		pos = p0 + function_len;
	}
	pr_cont("\n");
	if (!id_string_used) {
		kfree(board);
	}
	
	if (pos != es->config_data_length) {
		printk(KERN_ERR "eisa_enumerator: config data length mis-match got %d, expected %d\n",
			pos, es->config_data_length);
		res=-1;
	}
	
	if (num_func != es->num_functions) {
		printk(KERN_ERR "eisa_enumerator: number of functions mis-match got %d, expected %d\n",
			num_func, es->num_functions);
		res=-2;
	}
	
	return res;
	
}