3 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
5 * See file CREDITS for list of people who contributed to this
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.
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.
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,
26 #include <asm/arch/hardware.h>
27 #include "designware_i2c.h"
29 #ifdef CONFIG_I2C_MULTI_BUS
30 static unsigned int bus_initialized[CONFIG_SYS_I2C_BUS_MAX];
31 static unsigned int current_bus = 0;
34 static struct i2c_regs *i2c_regs_p =
35 (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
38 * set_speed - Set the i2c speed mode (standard, high, fast)
39 * @i2c_spd: required i2c speed mode
41 * Set the i2c speed mode (standard, high, fast)
43 static void set_speed(int i2c_spd)
46 unsigned int hcnt, lcnt;
49 /* to set speed cltr must be disabled */
50 enbl = readl(&i2c_regs_p->ic_enable);
51 enbl &= ~IC_ENABLE_0B;
52 writel(enbl, &i2c_regs_p->ic_enable);
54 cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
57 case IC_SPEED_MODE_MAX:
58 cntl |= IC_CON_SPD_HS;
59 hcnt = (IC_CLK * MIN_HS_SCL_HIGHTIME) / NANO_TO_MICRO;
60 writel(hcnt, &i2c_regs_p->ic_hs_scl_hcnt);
61 lcnt = (IC_CLK * MIN_HS_SCL_LOWTIME) / NANO_TO_MICRO;
62 writel(lcnt, &i2c_regs_p->ic_hs_scl_lcnt);
65 case IC_SPEED_MODE_STANDARD:
66 cntl |= IC_CON_SPD_SS;
67 hcnt = (IC_CLK * MIN_SS_SCL_HIGHTIME) / NANO_TO_MICRO;
68 writel(hcnt, &i2c_regs_p->ic_ss_scl_hcnt);
69 lcnt = (IC_CLK * MIN_SS_SCL_LOWTIME) / NANO_TO_MICRO;
70 writel(lcnt, &i2c_regs_p->ic_ss_scl_lcnt);
73 case IC_SPEED_MODE_FAST:
75 cntl |= IC_CON_SPD_FS;
76 hcnt = (IC_CLK * MIN_FS_SCL_HIGHTIME) / NANO_TO_MICRO;
77 writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
78 lcnt = (IC_CLK * MIN_FS_SCL_LOWTIME) / NANO_TO_MICRO;
79 writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
83 writel(cntl, &i2c_regs_p->ic_con);
85 /* Enable back i2c now speed set */
87 writel(enbl, &i2c_regs_p->ic_enable);
91 * i2c_set_bus_speed - Set the i2c speed
92 * @speed: required i2c speed
96 int i2c_set_bus_speed(int speed)
98 if (speed >= I2C_MAX_SPEED)
99 set_speed(IC_SPEED_MODE_MAX);
100 else if (speed >= I2C_FAST_SPEED)
101 set_speed(IC_SPEED_MODE_FAST);
103 set_speed(IC_SPEED_MODE_STANDARD);
109 * i2c_get_bus_speed - Gets the i2c speed
111 * Gets the i2c speed.
113 int i2c_get_bus_speed(void)
117 cntl = (readl(&i2c_regs_p->ic_con) & IC_CON_SPD_MSK);
119 if (cntl == IC_CON_SPD_HS)
120 return I2C_MAX_SPEED;
121 else if (cntl == IC_CON_SPD_FS)
122 return I2C_FAST_SPEED;
123 else if (cntl == IC_CON_SPD_SS)
124 return I2C_STANDARD_SPEED;
130 * i2c_init - Init function
131 * @speed: required i2c speed
132 * @slaveadd: slave address for the device
134 * Initialization function.
136 void i2c_init(int speed, int slaveadd)
141 enbl = readl(&i2c_regs_p->ic_enable);
142 enbl &= ~IC_ENABLE_0B;
143 writel(enbl, &i2c_regs_p->ic_enable);
145 writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_regs_p->ic_con);
146 writel(IC_RX_TL, &i2c_regs_p->ic_rx_tl);
147 writel(IC_TX_TL, &i2c_regs_p->ic_tx_tl);
148 i2c_set_bus_speed(speed);
149 writel(IC_STOP_DET, &i2c_regs_p->ic_intr_mask);
150 writel(slaveadd, &i2c_regs_p->ic_sar);
153 enbl = readl(&i2c_regs_p->ic_enable);
154 enbl |= IC_ENABLE_0B;
155 writel(enbl, &i2c_regs_p->ic_enable);
157 #ifdef CONFIG_I2C_MULTI_BUS
158 bus_initialized[current_bus] = 1;
163 * i2c_setaddress - Sets the target slave address
164 * @i2c_addr: target i2c address
166 * Sets the target slave address.
168 static void i2c_setaddress(unsigned int i2c_addr)
170 writel(i2c_addr, &i2c_regs_p->ic_tar);
174 * i2c_flush_rxfifo - Flushes the i2c RX FIFO
176 * Flushes the i2c RX FIFO
178 static void i2c_flush_rxfifo(void)
180 while (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE)
181 readl(&i2c_regs_p->ic_cmd_data);
185 * i2c_wait_for_bb - Waits for bus busy
189 static int i2c_wait_for_bb(void)
191 unsigned long start_time_bb = get_timer(0);
193 while ((readl(&i2c_regs_p->ic_status) & IC_STATUS_MA) ||
194 !(readl(&i2c_regs_p->ic_status) & IC_STATUS_TFE)) {
196 /* Evaluate timeout */
197 if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
204 /* check parameters for i2c_read and i2c_write */
205 static int check_params(uint addr, int alen, uchar *buffer, int len)
207 if (buffer == NULL) {
208 printf("Buffer is invalid\n");
213 printf("addr len %d not supported\n", alen);
217 if (addr + len > 256) {
218 printf("address out of range\n");
225 static int i2c_xfer_init(uchar chip, uint addr)
227 if (i2c_wait_for_bb())
230 i2c_setaddress(chip);
231 writel(addr, &i2c_regs_p->ic_cmd_data);
236 static int i2c_xfer_finish(void)
238 ulong start_stop_det = get_timer(0);
241 if ((readl(&i2c_regs_p->ic_raw_intr_stat) & IC_STOP_DET)) {
242 readl(&i2c_regs_p->ic_clr_stop_det);
244 } else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
249 if (i2c_wait_for_bb()) {
250 printf("Timed out waiting for bus\n");
256 /* Wait for read/write operation to complete on actual memory */
263 * i2c_read - Read from i2c memory
264 * @chip: target i2c address
265 * @addr: address to read from
267 * @buffer: buffer for read data
268 * @len: no of bytes to be read
270 * Read from i2c memory.
272 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
274 unsigned long start_time_rx;
276 if (check_params(addr, alen, buffer, len))
279 if (i2c_xfer_init(chip, addr))
282 start_time_rx = get_timer(0);
285 writel(IC_CMD | IC_STOP, &i2c_regs_p->ic_cmd_data);
287 writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
289 if (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE) {
290 *buffer++ = (uchar)readl(&i2c_regs_p->ic_cmd_data);
292 start_time_rx = get_timer(0);
294 } else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
299 return i2c_xfer_finish();
303 * i2c_write - Write to i2c memory
304 * @chip: target i2c address
305 * @addr: address to read from
307 * @buffer: buffer for read data
308 * @len: no of bytes to be read
310 * Write to i2c memory.
312 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
315 unsigned long start_time_tx;
317 if (check_params(addr, alen, buffer, len))
320 if (i2c_xfer_init(chip, addr))
323 start_time_tx = get_timer(0);
325 if (readl(&i2c_regs_p->ic_status) & IC_STATUS_TFNF) {
327 writel(*buffer | IC_STOP, &i2c_regs_p->ic_cmd_data);
329 writel(*buffer, &i2c_regs_p->ic_cmd_data);
331 start_time_tx = get_timer(0);
333 } else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
334 printf("Timed out. i2c write Failed\n");
339 return i2c_xfer_finish();
343 * i2c_probe - Probe the i2c chip
345 int i2c_probe(uchar chip)
351 * Try to read the first location of the chip.
353 ret = i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
355 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
360 #ifdef CONFIG_I2C_MULTI_BUS
361 int i2c_set_bus_num(unsigned int bus)
365 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE;
367 #ifdef CONFIG_SYS_I2C_BASE1
369 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE1;
372 #ifdef CONFIG_SYS_I2C_BASE2
374 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE2;
377 #ifdef CONFIG_SYS_I2C_BASE3
379 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE3;
382 #ifdef CONFIG_SYS_I2C_BASE4
384 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE4;
387 #ifdef CONFIG_SYS_I2C_BASE5
389 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE5;
392 #ifdef CONFIG_SYS_I2C_BASE6
394 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE6;
397 #ifdef CONFIG_SYS_I2C_BASE7
399 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE7;
402 #ifdef CONFIG_SYS_I2C_BASE8
404 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE8;
407 #ifdef CONFIG_SYS_I2C_BASE9
409 i2c_regs_p = (void *)CONFIG_SYS_I2C_BASE9;
413 printf("Bad bus: %d\n", bus);
419 if (!bus_initialized[current_bus])
420 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
425 int i2c_get_bus_num(void)