1 /*
2 * Utility to set the DAVINCI MUX register from a table in mux.h
3 *
4 * Author: Vladimir Barinov, MontaVista Software, Inc. <source@mvista.com>
5 *
6 * Based on linux/arch/arm/plat-omap/mux.c:
7 * Copyright (C) 2003 - 2005 Nokia Corporation
8 *
9 * Written by Tony Lindgren
10 *
11 * 2007 (c) MontaVista Software, Inc. This file is licensed under
12 * the terms of the GNU General Public License version 2. This program
13 * is licensed "as is" without any warranty of any kind, whether express
14 * or implied.
15 *
16 * Copyright (C) 2008 Texas Instruments.
17 */
18
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20
21 #include <linux/io.h>
22 #include <linux/module.h>
23 #include <linux/spinlock.h>
24
25 #include <mach/mux.h>
26 #include <mach/common.h>
27
28 static void __iomem *pinmux_base;
29
30 /*
31 * Sets the DAVINCI MUX register based on the table
32 */
davinci_cfg_reg(const unsigned long index)33 int davinci_cfg_reg(const unsigned long index)
34 {
35 static DEFINE_SPINLOCK(mux_spin_lock);
36 struct davinci_soc_info *soc_info = &davinci_soc_info;
37 unsigned long flags;
38 const struct mux_config *cfg;
39 unsigned int reg_orig = 0, reg = 0;
40 unsigned int mask, warn = 0;
41
42 if (WARN_ON(!soc_info->pinmux_pins))
43 return -ENODEV;
44
45 if (!pinmux_base) {
46 pinmux_base = ioremap(soc_info->pinmux_base, SZ_4K);
47 if (WARN_ON(!pinmux_base))
48 return -ENOMEM;
49 }
50
51 if (index >= soc_info->pinmux_pins_num) {
52 pr_err("Invalid pin mux index: %lu (%lu)\n",
53 index, soc_info->pinmux_pins_num);
54 dump_stack();
55 return -ENODEV;
56 }
57
58 cfg = &soc_info->pinmux_pins[index];
59
60 if (cfg->name == NULL) {
61 pr_err("No entry for the specified index\n");
62 return -ENODEV;
63 }
64
65 /* Update the mux register in question */
66 if (cfg->mask) {
67 unsigned tmp1, tmp2;
68
69 spin_lock_irqsave(&mux_spin_lock, flags);
70 reg_orig = __raw_readl(pinmux_base + cfg->mux_reg);
71
72 mask = (cfg->mask << cfg->mask_offset);
73 tmp1 = reg_orig & mask;
74 reg = reg_orig & ~mask;
75
76 tmp2 = (cfg->mode << cfg->mask_offset);
77 reg |= tmp2;
78
79 if (tmp1 != tmp2)
80 warn = 1;
81
82 __raw_writel(reg, pinmux_base + cfg->mux_reg);
83 spin_unlock_irqrestore(&mux_spin_lock, flags);
84 }
85
86 if (warn) {
87 #ifdef CONFIG_DAVINCI_MUX_WARNINGS
88 pr_warn("initialized %s\n", cfg->name);
89 #endif
90 }
91
92 #ifdef CONFIG_DAVINCI_MUX_DEBUG
93 if (cfg->debug || warn) {
94 pr_warn("Setting register %s\n", cfg->name);
95 pr_warn(" %s (0x%08x) = 0x%08x -> 0x%08x\n",
96 cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg);
97 }
98 #endif
99
100 return 0;
101 }
102 EXPORT_SYMBOL(davinci_cfg_reg);
103
davinci_cfg_reg_list(const short pins[])104 int davinci_cfg_reg_list(const short pins[])
105 {
106 int i, error = -EINVAL;
107
108 if (pins)
109 for (i = 0; pins[i] >= 0; i++) {
110 error = davinci_cfg_reg(pins[i]);
111 if (error)
112 break;
113 }
114
115 return error;
116 }
117