1 /* 2 * Copyright (c) 2015 Google, Inc 3 * Written by Simon Glass <sjg@chromium.org> 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #ifndef __REGMAP_H 9 #define __REGMAP_H 10 11 /** 12 * struct regmap_range - a register map range 13 * 14 * @start: Start address 15 * @size: Size in bytes 16 */ 17 struct regmap_range { 18 ulong start; 19 ulong size; 20 }; 21 22 /** 23 * struct regmap - a way of accessing hardware/bus registers 24 * 25 * @base: Base address of register map 26 * @range_count: Number of ranges available within the map 27 * @range: Pointer to the list of ranges, allocated if @range_count > 1 28 * @base_range: If @range_count is <= 1, @range points here 29 */ 30 struct regmap { 31 phys_addr_t base; 32 int range_count; 33 struct regmap_range *range, base_range; 34 }; 35 36 /* 37 * Interface to provide access to registers either through a direct memory 38 * bus or through a peripheral bus like I2C, SPI. 39 */ 40 int regmap_write(struct regmap *map, uint offset, uint val); 41 int regmap_read(struct regmap *map, uint offset, uint *valp); 42 43 #define regmap_write32(map, ptr, member, val) \ 44 regmap_write(map, (uint32_t *)(ptr)->member - (uint32_t *)(ptr), val) 45 46 #define regmap_read32(map, ptr, member, valp) \ 47 regmap_read(map, (uint32_t *)(ptr)->member - (uint32_t *)(ptr), valp) 48 49 /** 50 * regmap_read_poll_timeout - Poll until a condition is met or a timeout occurs 51 * 52 * @map: Regmap to read from 53 * @addr: Offset to poll 54 * @val: Unsigned integer variable to read the value into 55 * @cond: Break condition (usually involving @val) 56 * @sleep_us: Maximum time to sleep between reads in us (0 tight-loops). 57 * @timeout_ms: Timeout in ms, 0 means never timeout 58 * 59 * Returns 0 on success and -ETIMEDOUT upon a timeout or the regmap_read 60 * error return value in case of a error read. In the two former cases, 61 * the last read value at @addr is stored in @val. Must not be called 62 * from atomic context if sleep_us or timeout_us are used. 63 * 64 * This is modelled after the regmap_read_poll_timeout macros in linux but 65 * with millisecond timeout. 66 */ 67 #define regmap_read_poll_timeout(map, addr, val, cond, sleep_us, timeout_ms) \ 68 ({ \ 69 unsigned long __start = get_timer(0); \ 70 int __ret; \ 71 for (;;) { \ 72 __ret = regmap_read((map), (addr), &(val)); \ 73 if (__ret) \ 74 break; \ 75 if (cond) \ 76 break; \ 77 if ((timeout_ms) && get_timer(__start) > (timeout_ms)) { \ 78 __ret = regmap_read((map), (addr), &(val)); \ 79 break; \ 80 } \ 81 if ((sleep_us)) \ 82 udelay((sleep_us)); \ 83 } \ 84 __ret ?: ((cond) ? 0 : -ETIMEDOUT); \ 85 }) 86 87 /** 88 * regmap_init_mem() - Set up a new register map that uses memory access 89 * 90 * Use regmap_uninit() to free it. 91 * 92 * @dev: Device that uses this map 93 * @mapp: Returns allocated map 94 */ 95 int regmap_init_mem(struct udevice *dev, struct regmap **mapp); 96 97 /** 98 * regmap_init_mem_platdata() - Set up a new memory register map for of-platdata 99 * 100 * This creates a new regmap with a list of regions passed in, rather than 101 * using the device tree. It only supports 32-bit machines. 102 * 103 * Use regmap_uninit() to free it. 104 * 105 * @dev: Device that uses this map 106 * @reg: List of address, size pairs 107 * @count: Number of pairs (e.g. 1 if the regmap has a single entry) 108 * @mapp: Returns allocated map 109 */ 110 int regmap_init_mem_platdata(struct udevice *dev, fdt_val_t *reg, int count, 111 struct regmap **mapp); 112 113 /** 114 * regmap_get_range() - Obtain the base memory address of a regmap range 115 * 116 * @map: Regmap to query 117 * @range_num: Range to look up 118 */ 119 void *regmap_get_range(struct regmap *map, unsigned int range_num); 120 121 /** 122 * regmap_uninit() - free a previously inited regmap 123 */ 124 int regmap_uninit(struct regmap *map); 125 126 #endif 127