xref: /openbmc/linux/arch/arm/plat-orion/mpp.c (revision 63dc02bd)
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/mpp.h>
18 
19 /* Address of the ith MPP control register */
20 static __init unsigned long mpp_ctrl_addr(unsigned int i,
21 					  unsigned long dev_bus)
22 {
23 	return dev_bus + (i) * 4;
24 }
25 
26 
27 void __init orion_mpp_conf(unsigned int *mpp_list, unsigned int variant_mask,
28 			   unsigned int mpp_max, unsigned int dev_bus)
29 {
30 	unsigned int mpp_nr_regs = (1 + mpp_max/8);
31 	u32 mpp_ctrl[mpp_nr_regs];
32 	int i;
33 
34 	printk(KERN_DEBUG "initial MPP regs:");
35 	for (i = 0; i < mpp_nr_regs; i++) {
36 		mpp_ctrl[i] = readl(mpp_ctrl_addr(i, dev_bus));
37 		printk(" %08x", mpp_ctrl[i]);
38 	}
39 	printk("\n");
40 
41 	for ( ; *mpp_list; mpp_list++) {
42 		unsigned int num = MPP_NUM(*mpp_list);
43 		unsigned int sel = MPP_SEL(*mpp_list);
44 		int shift, gpio_mode;
45 
46 		if (num > mpp_max) {
47 			printk(KERN_ERR "orion_mpp_conf: invalid MPP "
48 					"number (%u)\n", num);
49 			continue;
50 		}
51 		if (variant_mask & !(*mpp_list & variant_mask)) {
52 			printk(KERN_WARNING
53 			       "orion_mpp_conf: requested MPP%u config "
54 			       "unavailable on this hardware\n", num);
55 			continue;
56 		}
57 
58 		shift = (num & 7) << 2;
59 		mpp_ctrl[num / 8] &= ~(0xf << shift);
60 		mpp_ctrl[num / 8] |= sel << shift;
61 
62 		gpio_mode = 0;
63 		if (*mpp_list & MPP_INPUT_MASK)
64 			gpio_mode |= GPIO_INPUT_OK;
65 		if (*mpp_list & MPP_OUTPUT_MASK)
66 			gpio_mode |= GPIO_OUTPUT_OK;
67 
68 		orion_gpio_set_valid(num, gpio_mode);
69 	}
70 
71 	printk(KERN_DEBUG "  final MPP regs:");
72 	for (i = 0; i < mpp_nr_regs; i++) {
73 		writel(mpp_ctrl[i], mpp_ctrl_addr(i, dev_bus));
74 		printk(" %08x", mpp_ctrl[i]);
75 	}
76 	printk("\n");
77 }
78