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1/*
2 * (C) Copyright 2009
3 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
4 *
1a459660 5 * SPDX-License-Identifier: GPL-2.0+
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6 */
7
8#include <common.h>
9#include <asm/io.h>
10#include <asm/arch/hardware.h>
031ed2fa 11#include "designware_i2c.h"
2403f8f4 12
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13#ifdef CONFIG_I2C_MULTI_BUS
14static unsigned int bus_initialized[CONFIG_SYS_I2C_BUS_MAX];
15static unsigned int current_bus = 0;
16#endif
17
18static struct i2c_regs *i2c_regs_p =
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19 (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
20
21/*
22 * set_speed - Set the i2c speed mode (standard, high, fast)
23 * @i2c_spd: required i2c speed mode
24 *
25 * Set the i2c speed mode (standard, high, fast)
26 */
27static void set_speed(int i2c_spd)
28{
29 unsigned int cntl;
30 unsigned int hcnt, lcnt;
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31 unsigned int enbl;
32
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);
37
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38 cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
39
40 switch (i2c_spd) {
41 case IC_SPEED_MODE_MAX:
42 cntl |= IC_CON_SPD_HS;
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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);
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47 break;
48
49 case IC_SPEED_MODE_STANDARD:
50 cntl |= IC_CON_SPD_SS;
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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);
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55 break;
56
57 case IC_SPEED_MODE_FAST:
58 default:
59 cntl |= IC_CON_SPD_FS;
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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);
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64 break;
65 }
66
67 writel(cntl, &i2c_regs_p->ic_con);
68
5b8439bb 69 /* Enable back i2c now speed set */
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70 enbl |= IC_ENABLE_0B;
71 writel(enbl, &i2c_regs_p->ic_enable);
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72}
73
74/*
75 * i2c_set_bus_speed - Set the i2c speed
76 * @speed: required i2c speed
77 *
78 * Set the i2c speed.
79 */
496ba48f 80int i2c_set_bus_speed(int speed)
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81{
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);
86 else
87 set_speed(IC_SPEED_MODE_STANDARD);
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88
89 return 0;
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90}
91
92/*
93 * i2c_get_bus_speed - Gets the i2c speed
94 *
95 * Gets the i2c speed.
96 */
97int i2c_get_bus_speed(void)
98{
99 u32 cntl;
100
101 cntl = (readl(&i2c_regs_p->ic_con) & IC_CON_SPD_MSK);
102
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;
109
110 return 0;
111}
112
113/*
114 * i2c_init - Init function
115 * @speed: required i2c speed
031ed2fa 116 * @slaveadd: slave address for the device
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117 *
118 * Initialization function.
119 */
120void i2c_init(int speed, int slaveadd)
121{
122 unsigned int enbl;
123
124 /* Disable i2c */
125 enbl = readl(&i2c_regs_p->ic_enable);
126 enbl &= ~IC_ENABLE_0B;
127 writel(enbl, &i2c_regs_p->ic_enable);
128
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);
135
136 /* Enable i2c */
137 enbl = readl(&i2c_regs_p->ic_enable);
138 enbl |= IC_ENABLE_0B;
139 writel(enbl, &i2c_regs_p->ic_enable);
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140
141#ifdef CONFIG_I2C_MULTI_BUS
142 bus_initialized[current_bus] = 1;
143#endif
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144}
145
146/*
147 * i2c_setaddress - Sets the target slave address
148 * @i2c_addr: target i2c address
149 *
150 * Sets the target slave address.
151 */
152static void i2c_setaddress(unsigned int i2c_addr)
153{
154 writel(i2c_addr, &i2c_regs_p->ic_tar);
155}
156
157/*
158 * i2c_flush_rxfifo - Flushes the i2c RX FIFO
159 *
160 * Flushes the i2c RX FIFO
161 */
162static void i2c_flush_rxfifo(void)
163{
164 while (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE)
165 readl(&i2c_regs_p->ic_cmd_data);
166}
167
168/*
169 * i2c_wait_for_bb - Waits for bus busy
170 *
171 * Waits for bus busy
172 */
173static int i2c_wait_for_bb(void)
174{
175 unsigned long start_time_bb = get_timer(0);
176
177 while ((readl(&i2c_regs_p->ic_status) & IC_STATUS_MA) ||
178 !(readl(&i2c_regs_p->ic_status) & IC_STATUS_TFE)) {
179
180 /* Evaluate timeout */
181 if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
182 return 1;
183 }
184
185 return 0;
186}
187
188/* check parameters for i2c_read and i2c_write */
189static int check_params(uint addr, int alen, uchar *buffer, int len)
190{
191 if (buffer == NULL) {
192 printf("Buffer is invalid\n");
193 return 1;
194 }
195
196 if (alen > 1) {
197 printf("addr len %d not supported\n", alen);
198 return 1;
199 }
200
201 if (addr + len > 256) {
202 printf("address out of range\n");
203 return 1;
204 }
205
206 return 0;
207}
208
209static int i2c_xfer_init(uchar chip, uint addr)
210{
496ba48f 211 if (i2c_wait_for_bb())
2403f8f4 212 return 1;
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213
214 i2c_setaddress(chip);
215 writel(addr, &i2c_regs_p->ic_cmd_data);
216
217 return 0;
218}
219
220static int i2c_xfer_finish(void)
221{
222 ulong start_stop_det = get_timer(0);
223
224 while (1) {
225 if ((readl(&i2c_regs_p->ic_raw_intr_stat) & IC_STOP_DET)) {
226 readl(&i2c_regs_p->ic_clr_stop_det);
227 break;
228 } else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
229 break;
230 }
231 }
232
233 if (i2c_wait_for_bb()) {
234 printf("Timed out waiting for bus\n");
235 return 1;
236 }
237
238 i2c_flush_rxfifo();
239
240 /* Wait for read/write operation to complete on actual memory */
241 udelay(10000);
242
243 return 0;
244}
245
246/*
247 * i2c_read - Read from i2c memory
248 * @chip: target i2c address
249 * @addr: address to read from
250 * @alen:
251 * @buffer: buffer for read data
252 * @len: no of bytes to be read
253 *
254 * Read from i2c memory.
255 */
256int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
257{
258 unsigned long start_time_rx;
259
260 if (check_params(addr, alen, buffer, len))
261 return 1;
262
263 if (i2c_xfer_init(chip, addr))
264 return 1;
265
266 start_time_rx = get_timer(0);
267 while (len) {
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268 if (len == 1)
269 writel(IC_CMD | IC_STOP, &i2c_regs_p->ic_cmd_data);
270 else
271 writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
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272
273 if (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE) {
274 *buffer++ = (uchar)readl(&i2c_regs_p->ic_cmd_data);
275 len--;
276 start_time_rx = get_timer(0);
277
278 } else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
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279 return 1;
280 }
281 }
282
283 return i2c_xfer_finish();
284}
285
286/*
287 * i2c_write - Write to i2c memory
288 * @chip: target i2c address
289 * @addr: address to read from
290 * @alen:
291 * @buffer: buffer for read data
292 * @len: no of bytes to be read
293 *
294 * Write to i2c memory.
295 */
296int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
297{
298 int nb = len;
299 unsigned long start_time_tx;
300
301 if (check_params(addr, alen, buffer, len))
302 return 1;
303
304 if (i2c_xfer_init(chip, addr))
305 return 1;
306
307 start_time_tx = get_timer(0);
308 while (len) {
309 if (readl(&i2c_regs_p->ic_status) & IC_STATUS_TFNF) {
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310 if (--len == 0)
311 writel(*buffer | IC_STOP, &i2c_regs_p->ic_cmd_data);
312 else
313 writel(*buffer, &i2c_regs_p->ic_cmd_data);
2403f8f4 314 buffer++;
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315 start_time_tx = get_timer(0);
316
317 } else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
318 printf("Timed out. i2c write Failed\n");
319 return 1;
320 }
321 }
322
323 return i2c_xfer_finish();
324}
325
326/*
327 * i2c_probe - Probe the i2c chip
328 */
329int i2c_probe(uchar chip)
330{
331 u32 tmp;
496ba48f 332 int ret;
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333
334 /*
335 * Try to read the first location of the chip.
336 */
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337 ret = i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
338 if (ret)
339 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
340
341 return ret;
2403f8f4 342}
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343
344#ifdef CONFIG_I2C_MULTI_BUS
345int i2c_set_bus_num(unsigned int bus)
346{
347 switch (bus) {
348 case 0:
349 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE;
350 break;
351#ifdef CONFIG_SYS_I2C_BASE1
352 case 1:
353 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE1;
354 break;
355#endif
356#ifdef CONFIG_SYS_I2C_BASE2
357 case 2:
358 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE2;
359 break;
360#endif
361#ifdef CONFIG_SYS_I2C_BASE3
362 case 3:
363 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE3;
364 break;
365#endif
366#ifdef CONFIG_SYS_I2C_BASE4
367 case 4:
368 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE4;
369 break;
370#endif
371#ifdef CONFIG_SYS_I2C_BASE5
372 case 5:
373 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE5;
374 break;
375#endif
376#ifdef CONFIG_SYS_I2C_BASE6
377 case 6:
378 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE6;
379 break;
380#endif
381#ifdef CONFIG_SYS_I2C_BASE7
382 case 7:
383 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE7;
384 break;
385#endif
386#ifdef CONFIG_SYS_I2C_BASE8
387 case 8:
388 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE8;
389 break;
390#endif
391#ifdef CONFIG_SYS_I2C_BASE9
392 case 9:
393 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE9;
394 break;
395#endif
396 default:
397 printf("Bad bus: %d\n", bus);
398 return -1;
399 }
400
401 current_bus = bus;
402
403 if (!bus_initialized[current_bus])
404 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
405
406 return 0;
407}
408
409int i2c_get_bus_num(void)
410{
411 return current_bus;
412}
413#endif