1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Utility to set the DAVINCI MUX register from a table in mux.h 4 * 5 * Author: Vladimir Barinov, MontaVista Software, Inc. <source@mvista.com> 6 * 7 * Based on linux/arch/arm/plat-omap/mux.c: 8 * Copyright (C) 2003 - 2005 Nokia Corporation 9 * 10 * Written by Tony Lindgren 11 * 12 * 2007 (c) MontaVista Software, Inc. 13 * 14 * Copyright (C) 2008 Texas Instruments. 15 */ 16 17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 18 19 #include <linux/io.h> 20 #include <linux/module.h> 21 #include <linux/spinlock.h> 22 23 #include "mux.h" 24 #include "common.h" 25 26 static void __iomem *pinmux_base; 27 28 /* 29 * Sets the DAVINCI MUX register based on the table 30 */ 31 int davinci_cfg_reg(const unsigned long index) 32 { 33 static DEFINE_SPINLOCK(mux_spin_lock); 34 struct davinci_soc_info *soc_info = &davinci_soc_info; 35 unsigned long flags; 36 const struct mux_config *cfg; 37 unsigned int reg_orig = 0, reg = 0; 38 unsigned int mask, warn = 0; 39 40 if (WARN_ON(!soc_info->pinmux_pins)) 41 return -ENODEV; 42 43 if (!pinmux_base) { 44 pinmux_base = ioremap(soc_info->pinmux_base, SZ_4K); 45 if (WARN_ON(!pinmux_base)) 46 return -ENOMEM; 47 } 48 49 if (index >= soc_info->pinmux_pins_num) { 50 pr_err("Invalid pin mux index: %lu (%lu)\n", 51 index, soc_info->pinmux_pins_num); 52 dump_stack(); 53 return -ENODEV; 54 } 55 56 cfg = &soc_info->pinmux_pins[index]; 57 58 if (cfg->name == NULL) { 59 pr_err("No entry for the specified index\n"); 60 return -ENODEV; 61 } 62 63 /* Update the mux register in question */ 64 if (cfg->mask) { 65 unsigned tmp1, tmp2; 66 67 spin_lock_irqsave(&mux_spin_lock, flags); 68 reg_orig = __raw_readl(pinmux_base + cfg->mux_reg); 69 70 mask = (cfg->mask << cfg->mask_offset); 71 tmp1 = reg_orig & mask; 72 reg = reg_orig & ~mask; 73 74 tmp2 = (cfg->mode << cfg->mask_offset); 75 reg |= tmp2; 76 77 if (tmp1 != tmp2) 78 warn = 1; 79 80 __raw_writel(reg, pinmux_base + cfg->mux_reg); 81 spin_unlock_irqrestore(&mux_spin_lock, flags); 82 } 83 84 if (warn) { 85 #ifdef CONFIG_DAVINCI_MUX_WARNINGS 86 pr_warn("initialized %s\n", cfg->name); 87 #endif 88 } 89 90 #ifdef CONFIG_DAVINCI_MUX_DEBUG 91 if (cfg->debug || warn) { 92 pr_warn("Setting register %s\n", cfg->name); 93 pr_warn(" %s (0x%08x) = 0x%08x -> 0x%08x\n", 94 cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg); 95 } 96 #endif 97 98 return 0; 99 } 100 EXPORT_SYMBOL(davinci_cfg_reg); 101 102 int davinci_cfg_reg_list(const short pins[]) 103 { 104 int i, error = -EINVAL; 105 106 if (pins) 107 for (i = 0; pins[i] >= 0; i++) { 108 error = davinci_cfg_reg(pins[i]); 109 if (error) 110 break; 111 } 112 113 return error; 114 } 115