]>
git.ipfire.org Git - people/ms/u-boot.git/blob - drivers/i2c/i2c_core.c
2 * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
5 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
7 * Multibus/multiadapter I2C core functions (wrappers)
9 * SPDX-License-Identifier: GPL-2.0+
14 struct i2c_adapter
*i2c_get_adapter(int index
)
16 struct i2c_adapter
*i2c_adap_p
= ll_entry_start(struct i2c_adapter
,
18 int max
= ll_entry_count(struct i2c_adapter
, i2c
);
22 printf("Error, wrong i2c adapter %d max %d possible\n",
29 for (i
= 0; i
< index
; i
++)
35 #if !defined(CONFIG_SYS_I2C_DIRECT_BUS)
36 struct i2c_bus_hose i2c_bus
[CONFIG_SYS_NUM_I2C_BUSES
] =
40 DECLARE_GLOBAL_DATA_PTR
;
42 void i2c_reloc_fixup(void)
44 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
45 struct i2c_adapter
*i2c_adap_p
= ll_entry_start(struct i2c_adapter
,
47 struct i2c_adapter
*tmp
= i2c_adap_p
;
48 int max
= ll_entry_count(struct i2c_adapter
, i2c
);
52 if (gd
->reloc_off
== 0)
55 for (i
= 0; i
< max
; i
++) {
57 addr
= (unsigned long)i2c_adap_p
;
58 addr
+= gd
->reloc_off
;
59 i2c_adap_p
= (struct i2c_adapter
*)addr
;
61 addr
= (unsigned long)i2c_adap_p
->init
;
62 addr
+= gd
->reloc_off
;
63 i2c_adap_p
->init
= (void (*)(int, int))addr
;
65 addr
= (unsigned long)i2c_adap_p
->probe
;
66 addr
+= gd
->reloc_off
;
67 i2c_adap_p
->probe
= (int (*)(uint8_t))addr
;
69 addr
= (unsigned long)i2c_adap_p
->read
;
70 addr
+= gd
->reloc_off
;
71 i2c_adap_p
->read
= (int (*)(uint8_t, uint
, int, uint8_t *,
74 addr
= (unsigned long)i2c_adap_p
->write
;
75 addr
+= gd
->reloc_off
;
76 i2c_adap_p
->write
= (int (*)(uint8_t, uint
, int, uint8_t *,
78 /* i2c_set_bus_speed() */
79 addr
= (unsigned long)i2c_adap_p
->set_bus_speed
;
80 addr
+= gd
->reloc_off
;
81 i2c_adap_p
->set_bus_speed
= (uint (*)(uint
))addr
;
83 addr
= (unsigned long)i2c_adap_p
->name
;
84 addr
+= gd
->reloc_off
;
85 i2c_adap_p
->name
= (char *)addr
;
92 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
97 * This turns on the given channel on I2C multiplexer chip connected to
98 * a given I2C adapter directly or via other multiplexers. In the latter
99 * case the entire multiplexer chain must be initialized first starting
100 * with the one connected directly to the adapter. When disabling a chain
101 * muxes must be programmed in reverse order, starting with the one
102 * farthest from the adapter.
104 * mux_id is the multiplexer chip type from defined in i2c.h. So far only
105 * NXP (Philips) PCA954x multiplexers are supported. Switches are NOT
106 * supported (anybody uses them?)
109 static int i2c_mux_set(struct i2c_adapter
*adap
, int mux_id
, int chip
,
115 /* channel < 0 - turn off the mux */
118 ret
= adap
->write(adap
, chip
, 0, 0, &buf
, 1);
120 printf("%s: Could not turn off the mux.\n", __func__
);
125 case I2C_MUX_PCA9540_ID
:
126 case I2C_MUX_PCA9542_ID
:
129 buf
= (uint8_t)((channel
& 0x01) | (1 << 2));
131 case I2C_MUX_PCA9544_ID
:
134 buf
= (uint8_t)((channel
& 0x03) | (1 << 2));
136 case I2C_MUX_PCA9547_ID
:
139 buf
= (uint8_t)((channel
& 0x07) | (1 << 3));
142 printf("%s: wrong mux id: %d\n", __func__
, mux_id
);
146 ret
= adap
->write(adap
, chip
, 0, 0, &buf
, 1);
148 printf("%s: could not set mux: id: %d chip: %x channel: %d\n",
149 __func__
, mux_id
, chip
, channel
);
153 static int i2c_mux_set_all(void)
155 struct i2c_bus_hose
*i2c_bus_tmp
= &i2c_bus
[I2C_BUS
];
158 /* Connect requested bus if behind muxes */
159 if (i2c_bus_tmp
->next_hop
[0].chip
!= 0) {
160 /* Set all muxes along the path to that bus */
161 for (i
= 0; i
< CONFIG_SYS_I2C_MAX_HOPS
; i
++) {
164 if (i2c_bus_tmp
->next_hop
[i
].chip
== 0)
167 ret
= i2c_mux_set(I2C_ADAP
,
168 i2c_bus_tmp
->next_hop
[i
].mux
.id
,
169 i2c_bus_tmp
->next_hop
[i
].chip
,
170 i2c_bus_tmp
->next_hop
[i
].channel
);
178 static int i2c_mux_disconnet_all(void)
180 struct i2c_bus_hose
*i2c_bus_tmp
= &i2c_bus
[I2C_BUS
];
184 if (I2C_ADAP
->init_done
== 0)
187 /* Disconnect current bus (turn off muxes if any) */
188 if ((i2c_bus_tmp
->next_hop
[0].chip
!= 0) &&
189 (I2C_ADAP
->init_done
!= 0)) {
190 i
= CONFIG_SYS_I2C_MAX_HOPS
;
195 chip
= i2c_bus_tmp
->next_hop
[--i
].chip
;
199 ret
= I2C_ADAP
->write(I2C_ADAP
, chip
, 0, 0, &buf
, 1);
201 printf("i2c: mux diconnect error\n");
215 * Initializes one bus. Will initialize the parent adapter. No current bus
216 * changes, no mux (if any) setup.
218 static void i2c_init_bus(unsigned int bus_no
, int speed
, int slaveaddr
)
220 if (bus_no
>= CONFIG_SYS_NUM_I2C_BUSES
)
223 I2C_ADAP
->init(I2C_ADAP
, speed
, slaveaddr
);
225 if (gd
->flags
& GD_FLG_RELOC
) {
226 I2C_ADAP
->init_done
= 1;
227 I2C_ADAP
->speed
= speed
;
228 I2C_ADAP
->slaveaddr
= slaveaddr
;
232 /* implement possible board specific board init */
233 static void __def_i2c_init_board(void)
236 void i2c_init_board(void)
237 __attribute__((weak
, alias("__def_i2c_init_board")));
242 * not longer needed, will deleted. Actual init the SPD_BUS
244 * i2c_adap[] must be initialized beforehead with function pointers and
245 * data, including speed and slaveaddr.
247 void i2c_init_all(void)
250 i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM
);
258 * Returns index of currently active I2C bus. Zero-based.
260 unsigned int i2c_get_bus_num(void)
262 return gd
->cur_i2c_bus
;
269 * Change the active I2C bus. Subsequent read/write calls will
270 * go to this one. Sets all of the muxes in a proper condition
271 * if that bus is behind muxes.
272 * If previously selected bus is behind the muxes turns off all the
273 * muxes along the path to that bus.
275 * bus - bus index, zero based
277 * Returns: 0 on success, not 0 on failure
279 int i2c_set_bus_num(unsigned int bus
)
281 int max
= ll_entry_count(struct i2c_adapter
, i2c
);
283 if (I2C_ADAPTER(bus
) >= max
) {
284 printf("Error, wrong i2c adapter %d max %d possible\n",
285 I2C_ADAPTER(bus
), max
);
288 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
289 if (bus
>= CONFIG_SYS_NUM_I2C_BUSES
)
293 if ((bus
== I2C_BUS
) && (I2C_ADAP
->init_done
> 0))
296 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
297 i2c_mux_disconnet_all();
300 gd
->cur_i2c_bus
= bus
;
301 if (I2C_ADAP
->init_done
== 0)
302 i2c_init_bus(bus
, I2C_ADAP
->speed
, I2C_ADAP
->slaveaddr
);
304 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
311 * Probe the given I2C chip address. Returns 0 if a chip responded,
314 int i2c_probe(uint8_t chip
)
316 return I2C_ADAP
->probe(I2C_ADAP
, chip
);
320 * Read/Write interface:
321 * chip: I2C chip address, range 0..127
322 * addr: Memory (register) address within the chip
323 * alen: Number of bytes to use for addr (typically 1, 2 for larger
324 * memories, 0 for register type devices with only one
326 * buffer: Where to read/write the data
327 * len: How many bytes to read/write
329 * Returns: 0 on success, not 0 on failure
331 int i2c_read(uint8_t chip
, unsigned int addr
, int alen
,
332 uint8_t *buffer
, int len
)
334 return I2C_ADAP
->read(I2C_ADAP
, chip
, addr
, alen
, buffer
, len
);
337 int i2c_write(uint8_t chip
, unsigned int addr
, int alen
,
338 uint8_t *buffer
, int len
)
340 return I2C_ADAP
->write(I2C_ADAP
, chip
, addr
, alen
, buffer
, len
);
343 unsigned int i2c_set_bus_speed(unsigned int speed
)
347 if (I2C_ADAP
->set_bus_speed
== NULL
)
349 ret
= I2C_ADAP
->set_bus_speed(I2C_ADAP
, speed
);
350 if (gd
->flags
& GD_FLG_RELOC
)
351 I2C_ADAP
->speed
= ret
;
356 unsigned int i2c_get_bus_speed(void)
358 struct i2c_adapter
*cur
= I2C_ADAP
;
362 uint8_t i2c_reg_read(uint8_t addr
, uint8_t reg
)
367 /* MPC8xx needs this. Maybe one day we can get rid of it. */
368 /* maybe it is now the time for it ... */
369 i2c_set_bus_num(i2c_get_bus_num());
371 i2c_read(addr
, reg
, 1, &buf
, 1);
374 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
375 __func__
, i2c_get_bus_num(), addr
, reg
, buf
);
381 void i2c_reg_write(uint8_t addr
, uint8_t reg
, uint8_t val
)
384 /* MPC8xx needs this. Maybe one day we can get rid of it. */
385 /* maybe it is now the time for it ... */
386 i2c_set_bus_num(i2c_get_bus_num());
390 printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
391 __func__
, i2c_get_bus_num(), addr
, reg
, val
);
394 i2c_write(addr
, reg
, 1, &val
, 1);
397 void __i2c_init(int speed
, int slaveaddr
)
399 i2c_init_bus(i2c_get_bus_num(), speed
, slaveaddr
);
401 void i2c_init(int speed
, int slaveaddr
)
402 __attribute__((weak
, alias("__i2c_init")));