]>
git.ipfire.org Git - people/ms/u-boot.git/blob - drivers/i2c/designware_i2c.c
3 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
5 * SPDX-License-Identifier: GPL-2.0+
10 #include <asm/arch/hardware.h>
11 #include "designware_i2c.h"
13 #ifdef CONFIG_I2C_MULTI_BUS
14 static unsigned int bus_initialized
[CONFIG_SYS_I2C_BUS_MAX
];
15 static unsigned int current_bus
= 0;
18 static struct i2c_regs
*i2c_regs_p
=
19 (struct i2c_regs
*)CONFIG_SYS_I2C_BASE
;
22 * set_speed - Set the i2c speed mode (standard, high, fast)
23 * @i2c_spd: required i2c speed mode
25 * Set the i2c speed mode (standard, high, fast)
27 static void set_speed(int i2c_spd
)
30 unsigned int hcnt
, lcnt
;
33 /* to set speed cltr must be disabled */
34 enbl
= readl(&i2c_regs_p
->ic_enable
);
35 enbl
&= ~IC_ENABLE_0B
;
36 writel(enbl
, &i2c_regs_p
->ic_enable
);
38 cntl
= (readl(&i2c_regs_p
->ic_con
) & (~IC_CON_SPD_MSK
));
41 case IC_SPEED_MODE_MAX
:
42 cntl
|= IC_CON_SPD_HS
;
43 hcnt
= (IC_CLK
* MIN_HS_SCL_HIGHTIME
) / NANO_TO_MICRO
;
44 writel(hcnt
, &i2c_regs_p
->ic_hs_scl_hcnt
);
45 lcnt
= (IC_CLK
* MIN_HS_SCL_LOWTIME
) / NANO_TO_MICRO
;
46 writel(lcnt
, &i2c_regs_p
->ic_hs_scl_lcnt
);
49 case IC_SPEED_MODE_STANDARD
:
50 cntl
|= IC_CON_SPD_SS
;
51 hcnt
= (IC_CLK
* MIN_SS_SCL_HIGHTIME
) / NANO_TO_MICRO
;
52 writel(hcnt
, &i2c_regs_p
->ic_ss_scl_hcnt
);
53 lcnt
= (IC_CLK
* MIN_SS_SCL_LOWTIME
) / NANO_TO_MICRO
;
54 writel(lcnt
, &i2c_regs_p
->ic_ss_scl_lcnt
);
57 case IC_SPEED_MODE_FAST
:
59 cntl
|= IC_CON_SPD_FS
;
60 hcnt
= (IC_CLK
* MIN_FS_SCL_HIGHTIME
) / NANO_TO_MICRO
;
61 writel(hcnt
, &i2c_regs_p
->ic_fs_scl_hcnt
);
62 lcnt
= (IC_CLK
* MIN_FS_SCL_LOWTIME
) / NANO_TO_MICRO
;
63 writel(lcnt
, &i2c_regs_p
->ic_fs_scl_lcnt
);
67 writel(cntl
, &i2c_regs_p
->ic_con
);
69 /* Enable back i2c now speed set */
71 writel(enbl
, &i2c_regs_p
->ic_enable
);
75 * i2c_set_bus_speed - Set the i2c speed
76 * @speed: required i2c speed
80 int i2c_set_bus_speed(int speed
)
82 if (speed
>= I2C_MAX_SPEED
)
83 set_speed(IC_SPEED_MODE_MAX
);
84 else if (speed
>= I2C_FAST_SPEED
)
85 set_speed(IC_SPEED_MODE_FAST
);
87 set_speed(IC_SPEED_MODE_STANDARD
);
93 * i2c_get_bus_speed - Gets the i2c speed
97 int i2c_get_bus_speed(void)
101 cntl
= (readl(&i2c_regs_p
->ic_con
) & IC_CON_SPD_MSK
);
103 if (cntl
== IC_CON_SPD_HS
)
104 return I2C_MAX_SPEED
;
105 else if (cntl
== IC_CON_SPD_FS
)
106 return I2C_FAST_SPEED
;
107 else if (cntl
== IC_CON_SPD_SS
)
108 return I2C_STANDARD_SPEED
;
114 * i2c_init - Init function
115 * @speed: required i2c speed
116 * @slaveadd: slave address for the device
118 * Initialization function.
120 void i2c_init(int speed
, int slaveadd
)
125 enbl
= readl(&i2c_regs_p
->ic_enable
);
126 enbl
&= ~IC_ENABLE_0B
;
127 writel(enbl
, &i2c_regs_p
->ic_enable
);
129 writel((IC_CON_SD
| IC_CON_SPD_FS
| IC_CON_MM
), &i2c_regs_p
->ic_con
);
130 writel(IC_RX_TL
, &i2c_regs_p
->ic_rx_tl
);
131 writel(IC_TX_TL
, &i2c_regs_p
->ic_tx_tl
);
132 i2c_set_bus_speed(speed
);
133 writel(IC_STOP_DET
, &i2c_regs_p
->ic_intr_mask
);
134 writel(slaveadd
, &i2c_regs_p
->ic_sar
);
137 enbl
= readl(&i2c_regs_p
->ic_enable
);
138 enbl
|= IC_ENABLE_0B
;
139 writel(enbl
, &i2c_regs_p
->ic_enable
);
141 #ifdef CONFIG_I2C_MULTI_BUS
142 bus_initialized
[current_bus
] = 1;
147 * i2c_setaddress - Sets the target slave address
148 * @i2c_addr: target i2c address
150 * Sets the target slave address.
152 static void i2c_setaddress(unsigned int i2c_addr
)
154 writel(i2c_addr
, &i2c_regs_p
->ic_tar
);
158 * i2c_flush_rxfifo - Flushes the i2c RX FIFO
160 * Flushes the i2c RX FIFO
162 static void i2c_flush_rxfifo(void)
164 while (readl(&i2c_regs_p
->ic_status
) & IC_STATUS_RFNE
)
165 readl(&i2c_regs_p
->ic_cmd_data
);
169 * i2c_wait_for_bb - Waits for bus busy
173 static int i2c_wait_for_bb(void)
175 unsigned long start_time_bb
= get_timer(0);
177 while ((readl(&i2c_regs_p
->ic_status
) & IC_STATUS_MA
) ||
178 !(readl(&i2c_regs_p
->ic_status
) & IC_STATUS_TFE
)) {
180 /* Evaluate timeout */
181 if (get_timer(start_time_bb
) > (unsigned long)(I2C_BYTE_TO_BB
))
188 /* check parameters for i2c_read and i2c_write */
189 static int check_params(uint addr
, int alen
, uchar
*buffer
, int len
)
191 if (buffer
== NULL
) {
192 printf("Buffer is invalid\n");
197 printf("addr len %d not supported\n", alen
);
201 if (addr
+ len
> 256) {
202 printf("address out of range\n");
209 static int i2c_xfer_init(uchar chip
, uint addr
)
211 if (i2c_wait_for_bb())
214 i2c_setaddress(chip
);
215 writel(addr
, &i2c_regs_p
->ic_cmd_data
);
220 static int i2c_xfer_finish(void)
222 ulong start_stop_det
= get_timer(0);
225 if ((readl(&i2c_regs_p
->ic_raw_intr_stat
) & IC_STOP_DET
)) {
226 readl(&i2c_regs_p
->ic_clr_stop_det
);
228 } else if (get_timer(start_stop_det
) > I2C_STOPDET_TO
) {
233 if (i2c_wait_for_bb()) {
234 printf("Timed out waiting for bus\n");
240 /* Wait for read/write operation to complete on actual memory */
247 * i2c_read - Read from i2c memory
248 * @chip: target i2c address
249 * @addr: address to read from
251 * @buffer: buffer for read data
252 * @len: no of bytes to be read
254 * Read from i2c memory.
256 int i2c_read(uchar chip
, uint addr
, int alen
, uchar
*buffer
, int len
)
258 unsigned long start_time_rx
;
260 if (check_params(addr
, alen
, buffer
, len
))
263 if (i2c_xfer_init(chip
, addr
))
266 start_time_rx
= get_timer(0);
269 writel(IC_CMD
| IC_STOP
, &i2c_regs_p
->ic_cmd_data
);
271 writel(IC_CMD
, &i2c_regs_p
->ic_cmd_data
);
273 if (readl(&i2c_regs_p
->ic_status
) & IC_STATUS_RFNE
) {
274 *buffer
++ = (uchar
)readl(&i2c_regs_p
->ic_cmd_data
);
276 start_time_rx
= get_timer(0);
278 } else if (get_timer(start_time_rx
) > I2C_BYTE_TO
) {
283 return i2c_xfer_finish();
287 * i2c_write - Write to i2c memory
288 * @chip: target i2c address
289 * @addr: address to read from
291 * @buffer: buffer for read data
292 * @len: no of bytes to be read
294 * Write to i2c memory.
296 int i2c_write(uchar chip
, uint addr
, int alen
, uchar
*buffer
, int len
)
299 unsigned long start_time_tx
;
301 if (check_params(addr
, alen
, buffer
, len
))
304 if (i2c_xfer_init(chip
, addr
))
307 start_time_tx
= get_timer(0);
309 if (readl(&i2c_regs_p
->ic_status
) & IC_STATUS_TFNF
) {
311 writel(*buffer
| IC_STOP
, &i2c_regs_p
->ic_cmd_data
);
313 writel(*buffer
, &i2c_regs_p
->ic_cmd_data
);
315 start_time_tx
= get_timer(0);
317 } else if (get_timer(start_time_tx
) > (nb
* I2C_BYTE_TO
)) {
318 printf("Timed out. i2c write Failed\n");
323 return i2c_xfer_finish();
327 * i2c_probe - Probe the i2c chip
329 int i2c_probe(uchar chip
)
335 * Try to read the first location of the chip.
337 ret
= i2c_read(chip
, 0, 1, (uchar
*)&tmp
, 1);
339 i2c_init(CONFIG_SYS_I2C_SPEED
, CONFIG_SYS_I2C_SLAVE
);
344 #ifdef CONFIG_I2C_MULTI_BUS
345 int i2c_set_bus_num(unsigned int bus
)
349 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE
;
351 #ifdef CONFIG_SYS_I2C_BASE1
353 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE1
;
356 #ifdef CONFIG_SYS_I2C_BASE2
358 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE2
;
361 #ifdef CONFIG_SYS_I2C_BASE3
363 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE3
;
366 #ifdef CONFIG_SYS_I2C_BASE4
368 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE4
;
371 #ifdef CONFIG_SYS_I2C_BASE5
373 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE5
;
376 #ifdef CONFIG_SYS_I2C_BASE6
378 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE6
;
381 #ifdef CONFIG_SYS_I2C_BASE7
383 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE7
;
386 #ifdef CONFIG_SYS_I2C_BASE8
388 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE8
;
391 #ifdef CONFIG_SYS_I2C_BASE9
393 i2c_regs_p
= (void *)CONFIG_SYS_I2C_BASE9
;
397 printf("Bad bus: %d\n", bus
);
403 if (!bus_initialized
[current_bus
])
404 i2c_init(CONFIG_SYS_I2C_SPEED
, CONFIG_SYS_I2C_SLAVE
);
409 int i2c_get_bus_num(void)