xref: /openbmc/linux/arch/arm/plat-orion/mpp.c (revision 12eb4683)
1 /*
2  * arch/arm/plat-orion/mpp.c
3  *
4  * MPP functions for Marvell orion SoCs
5  *
6  * This file is licensed under the terms of the GNU General Public
7  * License version 2.  This program is licensed "as is" without any
8  * warranty of any kind, whether express or implied.
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/mbus.h>
14 #include <linux/io.h>
15 #include <linux/gpio.h>
16 #include <mach/hardware.h>
17 #include <plat/orion-gpio.h>
18 #include <plat/mpp.h>
19 
20 /* Address of the ith MPP control register */
21 static __init void __iomem *mpp_ctrl_addr(unsigned int i,
22 					  void __iomem *dev_bus)
23 {
24 	return dev_bus + (i) * 4;
25 }
26 
27 
28 void __init orion_mpp_conf(unsigned int *mpp_list, unsigned int variant_mask,
29 			   unsigned int mpp_max, void __iomem *dev_bus)
30 {
31 	unsigned int mpp_nr_regs = (1 + mpp_max/8);
32 	u32 mpp_ctrl[mpp_nr_regs];
33 	int i;
34 
35 	printk(KERN_DEBUG "initial MPP regs:");
36 	for (i = 0; i < mpp_nr_regs; i++) {
37 		mpp_ctrl[i] = readl(mpp_ctrl_addr(i, dev_bus));
38 		printk(" %08x", mpp_ctrl[i]);
39 	}
40 	printk("\n");
41 
42 	for ( ; *mpp_list; mpp_list++) {
43 		unsigned int num = MPP_NUM(*mpp_list);
44 		unsigned int sel = MPP_SEL(*mpp_list);
45 		int shift, gpio_mode;
46 
47 		if (num > mpp_max) {
48 			printk(KERN_ERR "orion_mpp_conf: invalid MPP "
49 					"number (%u)\n", num);
50 			continue;
51 		}
52 		if (variant_mask && !(*mpp_list & variant_mask)) {
53 			printk(KERN_WARNING
54 			       "orion_mpp_conf: requested MPP%u config "
55 			       "unavailable on this hardware\n", num);
56 			continue;
57 		}
58 
59 		shift = (num & 7) << 2;
60 		mpp_ctrl[num / 8] &= ~(0xf << shift);
61 		mpp_ctrl[num / 8] |= sel << shift;
62 
63 		gpio_mode = 0;
64 		if (*mpp_list & MPP_INPUT_MASK)
65 			gpio_mode |= GPIO_INPUT_OK;
66 		if (*mpp_list & MPP_OUTPUT_MASK)
67 			gpio_mode |= GPIO_OUTPUT_OK;
68 
69 		orion_gpio_set_valid(num, gpio_mode);
70 	}
71 
72 	printk(KERN_DEBUG "  final MPP regs:");
73 	for (i = 0; i < mpp_nr_regs; i++) {
74 		writel(mpp_ctrl[i], mpp_ctrl_addr(i, dev_bus));
75 		printk(" %08x", mpp_ctrl[i]);
76 	}
77 	printk("\n");
78 }
79