text: /*
   * arch/arm/mach-mv78x00/mpp.c
   *
   * MPP functions for Marvell MV78x00 SoCs
   *
   * This file is licensed under the terms of the GNU General Public
   * License version 2.  This program is licensed "as is" without any
   * warranty of any kind, whether express or implied.
   */
  
  #include <linux/kernel.h>
  #include <linux/init.h>
  #include <linux/mbus.h>
  #include <linux/io.h>
  #include <asm/gpio.h>
  #include <mach/hardware.h>
  #include "common.h"
  #include "mpp.h"
  
  static unsigned int __init mv78xx0_variant(void)
  {
  	u32 dev, rev;
  
  	mv78xx0_pcie_id(&dev, &rev);
  
  	if (dev == MV78100_DEV_ID && rev >= MV78100_REV_A0)
  		return MPP_78100_A0_MASK;
  
  	printk(KERN_ERR "MPP setup: unknown mv78x00 variant "
  			"(dev %#x rev %#x)\n", dev, rev);
  	return 0;
  }
  
  #define MPP_CTRL(i)	(DEV_BUS_VIRT_BASE + (i) * 4)
  #define MPP_NR_REGS	(1 + MPP_MAX/8)
  
  void __init mv78xx0_mpp_conf(unsigned int *mpp_list)
  {
  	u32 mpp_ctrl[MPP_NR_REGS];
  	unsigned int variant_mask;
  	int i;
  
  	variant_mask = mv78xx0_variant();
  	if (!variant_mask)
  		return;
  
  	/* Initialize gpiolib. */
  	orion_gpio_init();
  
  	printk(KERN_DEBUG "initial MPP regs:");
  	for (i = 0; i < MPP_NR_REGS; i++) {
  		mpp_ctrl[i] = readl(MPP_CTRL(i));
  		printk(" %08x", mpp_ctrl[i]);
  	}
  	printk("\n");
  
  	while (*mpp_list) {
  		unsigned int num = MPP_NUM(*mpp_list);
  		unsigned int sel = MPP_SEL(*mpp_list);
  		int shift, gpio_mode;
  
  		if (num > MPP_MAX) {
  			printk(KERN_ERR "mv78xx0_mpp_conf: invalid MPP "
  					"number (%u)\n", num);
  			continue;
  		}
  		if (!(*mpp_list & variant_mask)) {
  			printk(KERN_WARNING
  					"mv78xx0_mpp_conf: requested MPP%u config "
  					"unavailable on this hardware\n", num);
  			continue;
  		}
  
  		shift = (num & 7) << 2;
  		mpp_ctrl[num / 8] &= ~(0xf << shift);
  		mpp_ctrl[num / 8] |= sel << shift;
  
  		gpio_mode = 0;
  		if (*mpp_list & MPP_INPUT_MASK)
  			gpio_mode |= GPIO_INPUT_OK;
  		if (*mpp_list & MPP_OUTPUT_MASK)
  			gpio_mode |= GPIO_OUTPUT_OK;
  		if (sel != 0)
  			gpio_mode = 0;
  		orion_gpio_set_valid(num, gpio_mode);
  
  		mpp_list++;
  	}
  
  	printk(KERN_DEBUG "  final MPP regs:");
  	for (i = 0; i < MPP_NR_REGS; i++) {
  		writel(mpp_ctrl[i], MPP_CTRL(i));
  		printk(" %08x", mpp_ctrl[i]);
  	}
  	printk("\n");
  }
  