David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 1 | /* |
| 2 | * (C) Copyright 2001 |
| 3 | * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. |
| 4 | * |
| 5 | * See file CREDITS for list of people who contributed to this |
| 6 | * project. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License as |
| 10 | * published by the Free Software Foundation; either version 2 of |
| 11 | * the License, or (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License |
| 19 | * along with this program; if not, write to the Free Software |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 21 | * MA 02111-1307 USA |
| 22 | * |
| 23 | * The original I2C interface was |
| 24 | * (C) 2000 by Paolo Scaffardi (arsenio@tin.it) |
| 25 | * AIRVENT SAM s.p.a - RIMINI(ITALY) |
| 26 | * but has been changed substantially. |
| 27 | */ |
| 28 | |
| 29 | #ifndef _I2C_H_ |
| 30 | #define _I2C_H_ |
| 31 | |
| 32 | /* |
| 33 | * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING |
| 34 | * |
| 35 | * The implementation MUST NOT use static or global variables if the |
| 36 | * I2C routines are used to read SDRAM configuration information |
| 37 | * because this is done before the memories are initialized. Limited |
| 38 | * use of stack-based variables are OK (the initial stack size is |
| 39 | * limited). |
| 40 | * |
| 41 | * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING |
| 42 | */ |
| 43 | |
| 44 | /* |
| 45 | * Configuration items. |
| 46 | */ |
| 47 | #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */ |
| 48 | |
| 49 | #ifdef CONFIG_I2C_MULTI_BUS |
| 50 | #define MAX_I2C_BUS 2 |
| 51 | #define I2C_MULTI_BUS 1 |
| 52 | #else |
| 53 | #define MAX_I2C_BUS 1 |
| 54 | #define I2C_MULTI_BUS 0 |
| 55 | #endif |
| 56 | |
| 57 | #if !defined(CONFIG_SYS_MAX_I2C_BUS) |
| 58 | #define CONFIG_SYS_MAX_I2C_BUS MAX_I2C_BUS |
| 59 | #endif |
| 60 | |
| 61 | /* define the I2C bus number for RTC and DTT if not already done */ |
| 62 | #if !defined(CONFIG_SYS_RTC_BUS_NUM) |
| 63 | #define CONFIG_SYS_RTC_BUS_NUM 0 |
| 64 | #endif |
| 65 | #if !defined(CONFIG_SYS_DTT_BUS_NUM) |
| 66 | #define CONFIG_SYS_DTT_BUS_NUM 0 |
| 67 | #endif |
| 68 | #if !defined(CONFIG_SYS_SPD_BUS_NUM) |
| 69 | #define CONFIG_SYS_SPD_BUS_NUM 0 |
| 70 | #endif |
| 71 | |
| 72 | #ifndef I2C_SOFT_DECLARATIONS |
| 73 | # if defined(CONFIG_MPC8260) |
| 74 | # define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT); |
| 75 | # elif defined(CONFIG_8xx) |
| 76 | # define I2C_SOFT_DECLARATIONS volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR; |
| 77 | |
| 78 | # elif (defined(CONFIG_AT91RM9200) || \ |
| 79 | defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9261) || \ |
| 80 | defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY) |
| 81 | # define I2C_SOFT_DECLARATIONS at91_pio_t *pio = (at91_pio_t *) ATMEL_BASE_PIOA; |
| 82 | # else |
| 83 | # define I2C_SOFT_DECLARATIONS |
| 84 | # endif |
| 85 | #endif |
| 86 | |
| 87 | #ifdef CONFIG_8xx |
| 88 | /* Set default value for the I2C bus speed on 8xx. In the |
| 89 | * future, we'll define these in all 8xx board config files. |
| 90 | */ |
| 91 | #ifndef CONFIG_SYS_I2C_SPEED |
| 92 | #define CONFIG_SYS_I2C_SPEED 50000 |
| 93 | #endif |
| 94 | #endif |
| 95 | |
| 96 | /* |
| 97 | * Many boards/controllers/drivers don't support an I2C slave interface so |
| 98 | * provide a default slave address for them for use in common code. A real |
| 99 | * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does |
| 100 | * support a slave interface. |
| 101 | */ |
| 102 | #ifndef CONFIG_SYS_I2C_SLAVE |
| 103 | #define CONFIG_SYS_I2C_SLAVE 0xfe |
| 104 | #endif |
| 105 | |
| 106 | /* |
| 107 | * Initialization, must be called once on start up, may be called |
| 108 | * repeatedly to change the speed and slave addresses. |
| 109 | */ |
| 110 | void i2c_init(int speed, int slaveaddr); |
| 111 | void i2c_init_board(void); |
| 112 | #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT |
| 113 | void i2c_board_late_init(void); |
| 114 | #endif |
| 115 | |
| 116 | #if defined(CONFIG_I2C_MUX) |
| 117 | |
| 118 | typedef struct _mux { |
David Hendricks | d87d639 | 2013-02-05 15:17:56 -0800 | [diff] [blame] | 119 | unsigned char chip; |
| 120 | unsigned char channel; |
David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 121 | char *name; |
| 122 | struct _mux *next; |
| 123 | } I2C_MUX; |
| 124 | |
| 125 | typedef struct _mux_device { |
| 126 | int busid; |
| 127 | I2C_MUX *mux; /* List of muxes, to reach the device */ |
| 128 | struct _mux_device *next; |
| 129 | } I2C_MUX_DEVICE; |
| 130 | |
| 131 | I2C_MUX_DEVICE *i2c_mux_search_device(int id); |
David Hendricks | d87d639 | 2013-02-05 15:17:56 -0800 | [diff] [blame] | 132 | I2C_MUX_DEVICE *i2c_mux_ident_muxstring (unsigned char *buf); |
David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 133 | int i2x_mux_select_mux(int bus); |
David Hendricks | d87d639 | 2013-02-05 15:17:56 -0800 | [diff] [blame] | 134 | int i2c_mux_ident_muxstring_f (unsigned char *buf); |
David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 135 | #endif |
| 136 | |
| 137 | /* |
| 138 | * Probe the given I2C chip address. Returns 0 if a chip responded, |
| 139 | * not 0 on failure. |
| 140 | */ |
David Hendricks | d87d639 | 2013-02-05 15:17:56 -0800 | [diff] [blame] | 141 | int i2c_probe(unsigned char chip); |
David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 142 | |
| 143 | /* |
| 144 | * Read/Write interface: |
| 145 | * chip: I2C chip address, range 0..127 |
| 146 | * addr: Memory (register) address within the chip |
| 147 | * alen: Number of bytes to use for addr (typically 1, 2 for larger |
| 148 | * memories, 0 for register type devices with only one |
| 149 | * register) |
| 150 | * buffer: Where to read/write the data |
| 151 | * len: How many bytes to read/write |
| 152 | * |
| 153 | * Returns: 0 on success, not 0 on failure |
| 154 | */ |
David Hendricks | d87d639 | 2013-02-05 15:17:56 -0800 | [diff] [blame] | 155 | int i2c_read(unsigned char chip, unsigned int addr, int alen, |
| 156 | unsigned char *buffer, int len); |
| 157 | int i2c_write(unsigned char chip, unsigned int addr, int alen, |
| 158 | unsigned char *buffer, int len); |
David Hendricks | f4c3508 | 2012-12-27 14:15:51 -0800 | [diff] [blame] | 159 | |
| 160 | /* |
| 161 | * Utility routines to read/write registers. |
| 162 | */ |
| 163 | static inline u8 i2c_reg_read(u8 addr, u8 reg) |
| 164 | { |
| 165 | u8 buf; |
| 166 | |
| 167 | #ifdef CONFIG_8xx |
| 168 | /* MPC8xx needs this. Maybe one day we can get rid of it. */ |
| 169 | i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); |
| 170 | #endif |
| 171 | |
| 172 | #ifdef DEBUG |
| 173 | printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg); |
| 174 | #endif |
| 175 | |
| 176 | i2c_read(addr, reg, 1, &buf, 1); |
| 177 | |
| 178 | return buf; |
| 179 | } |
| 180 | |
| 181 | static inline void i2c_reg_write(u8 addr, u8 reg, u8 val) |
| 182 | { |
| 183 | #ifdef CONFIG_8xx |
| 184 | /* MPC8xx needs this. Maybe one day we can get rid of it. */ |
| 185 | i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); |
| 186 | #endif |
| 187 | |
| 188 | #ifdef DEBUG |
| 189 | printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n", |
| 190 | __func__, addr, reg, val); |
| 191 | #endif |
| 192 | |
| 193 | i2c_write(addr, reg, 1, &val, 1); |
| 194 | } |
| 195 | |
| 196 | /* |
| 197 | * Functions for setting the current I2C bus and its speed |
| 198 | */ |
| 199 | |
| 200 | /* |
| 201 | * i2c_set_bus_num: |
| 202 | * |
| 203 | * Change the active I2C bus. Subsequent read/write calls will |
| 204 | * go to this one. |
| 205 | * |
| 206 | * bus - bus index, zero based |
| 207 | * |
| 208 | * Returns: 0 on success, not 0 on failure |
| 209 | * |
| 210 | */ |
| 211 | int i2c_set_bus_num(unsigned int bus); |
| 212 | |
| 213 | /* |
| 214 | * i2c_get_bus_num: |
| 215 | * |
| 216 | * Returns index of currently active I2C bus. Zero-based. |
| 217 | */ |
| 218 | |
| 219 | unsigned int i2c_get_bus_num(void); |
| 220 | |
| 221 | /* |
| 222 | * i2c_set_bus_speed: |
| 223 | * |
| 224 | * Change the speed of the active I2C bus |
| 225 | * |
| 226 | * speed - bus speed in Hz |
| 227 | * |
| 228 | * Returns: 0 on success, not 0 on failure |
| 229 | * |
| 230 | */ |
| 231 | int i2c_set_bus_speed(unsigned int); |
| 232 | |
| 233 | /* |
| 234 | * i2c_get_bus_speed: |
| 235 | * |
| 236 | * Returns speed of currently active I2C bus in Hz |
| 237 | */ |
| 238 | |
| 239 | unsigned int i2c_get_bus_speed(void); |
| 240 | |
| 241 | /* NOTE: These two functions MUST be always_inline to avoid code growth! */ |
| 242 | static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline)); |
| 243 | static inline unsigned int I2C_GET_BUS(void) |
| 244 | { |
| 245 | return I2C_MULTI_BUS ? i2c_get_bus_num() : 0; |
| 246 | } |
| 247 | |
| 248 | static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline)); |
| 249 | static inline void I2C_SET_BUS(unsigned int bus) |
| 250 | { |
| 251 | if (I2C_MULTI_BUS) |
| 252 | i2c_set_bus_num(bus); |
| 253 | } |
| 254 | |
| 255 | /* |
| 256 | * Set an early register base for a given i2c peripheral. |
| 257 | * This is used to access a single i2c bus early on in the boot sequence. |
| 258 | * |
| 259 | * @param base: The base address of the i2c peripheral's register map |
| 260 | */ |
| 261 | void i2c_set_early_reg(unsigned int base); |
| 262 | |
| 263 | /** |
| 264 | * Find the I2C bus number by given a FDT I2C node. |
| 265 | * |
| 266 | * @param blob Device tree blbo |
| 267 | * @param node FDT I2C node to find |
| 268 | * @return the number of I2C bus (zero based), or -1 on error |
| 269 | */ |
| 270 | int i2c_get_bus_num_fdt(const void *blob, int node); |
| 271 | |
| 272 | /** |
| 273 | * Reset the I2C bus represented by the given a FDT I2C node. |
| 274 | * |
| 275 | * @param blob Device tree blbo |
| 276 | * @param node FDT I2C node to find |
| 277 | * @return 0 if port was reset, -1 if not found |
| 278 | */ |
| 279 | int i2c_reset_port_fdt(const void *blob, int node); |
| 280 | |
| 281 | #endif /* _I2C_H_ */ |