diff options
Diffstat (limited to 'board/esd/cpci750/i2c.c')
| -rwxr-xr-x | board/esd/cpci750/i2c.c | 487 |
1 files changed, 487 insertions, 0 deletions
diff --git a/board/esd/cpci750/i2c.c b/board/esd/cpci750/i2c.c new file mode 100755 index 0000000..5b1bc01 --- /dev/null +++ b/board/esd/cpci750/i2c.c @@ -0,0 +1,487 @@ +/* + * (C) Copyright 2000 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + * Hacked for the DB64360 board by Ingo.Assmus@keymile.com + * extra improvments by Brain Waite + * for cpci750 by reinhard.arlt@esd-electronics.com + */ +#include <common.h> +#include <mpc8xx.h> +#include <malloc.h> +#include "../../Marvell/include/mv_gen_reg.h" +#include "../../Marvell/include/core.h" + +#define I2C_DELAY 100 +#undef DEBUG_I2C + +#ifdef DEBUG_I2C +#define DP(x) x +#else +#define DP(x) +#endif + +/* Assuming that there is only one master on the bus (us) */ + +static void i2c_init (int speed, int slaveaddr) +{ + unsigned int n, m, freq, margin, power; + unsigned int actualN = 0, actualM = 0; + unsigned int minMargin = 0xffffffff; + unsigned int tclk = CFG_TCLK; + unsigned int i2cFreq = speed; /* 100000 max. Fast mode not supported */ + + DP (puts ("i2c_init\n")); +/* gtI2cMasterInit */ + for (n = 0; n < 8; n++) { + for (m = 0; m < 16; m++) { + power = 2 << n; /* power = 2^(n+1) */ + freq = tclk / (10 * (m + 1) * power); + if (i2cFreq > freq) + margin = i2cFreq - freq; + else + margin = freq - i2cFreq; + if (margin < minMargin) { + minMargin = margin; + actualN = n; + actualM = m; + } + } + } + + DP (puts ("setup i2c bus\n")); + + /* Setup bus */ + /* gtI2cReset */ + GT_REG_WRITE (I2C_SOFT_RESET, 0); + asm(" sync"); + GT_REG_WRITE (I2C_CONTROL, 0); + asm(" sync"); + + DP (puts ("set baudrate\n")); + + GT_REG_WRITE (I2C_STATUS_BAUDE_RATE, (actualM << 3) | actualN); + asm(" sync"); + + DP (puts ("udelay...\n")); + + udelay (I2C_DELAY); + + GT_REG_WRITE (I2C_CONTROL, (0x1 << 2) | (0x1 << 6)); + asm(" sync"); +} + + +static uchar i2c_select_device (uchar dev_addr, uchar read, int ten_bit) +{ + unsigned int status, data, bits = 7; + unsigned int control; + int count = 0; + + DP (puts ("i2c_select_device\n")); + + /* Output slave address */ + + if (ten_bit) { + bits = 10; + } + + GT_REG_READ (I2C_CONTROL, &control); + control |= (0x1 << 2); + GT_REG_WRITE (I2C_CONTROL, control); + asm(" sync"); + + GT_REG_READ (I2C_CONTROL, &control); + control |= (0x1 << 5); /* generate the I2C_START_BIT */ + GT_REG_WRITE (I2C_CONTROL, control); + asm(" sync"); + RESET_REG_BITS (I2C_CONTROL, (0x01 << 3)); + asm(" sync"); + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + + count = 0; + + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + while (((status & 0xff) != 0x08) && ((status & 0xff) != 0x10)){ + if (count > 200) { +#ifdef DEBUG_I2C + printf ("Failed to set startbit: 0x%02x\n", status); +#endif + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + asm(" sync"); + return (status); + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + } + + DP (puts ("i2c_select_device:write addr byte\n")); + + /* assert the address */ + + data = (dev_addr << 1); + /* set the read bit */ + data |= read; + GT_REG_WRITE (I2C_DATA, data); + asm(" sync"); + RESET_REG_BITS (I2C_CONTROL, BIT3); + asm(" sync"); + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count = 0; + while (((status & 0xff) != 0x40) && ((status & 0xff) != 0x18)) { + if (count > 200) { +#ifdef DEBUG_I2C + printf ("Failed to write address: 0x%02x\n", status); +#endif + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + return (status); + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + asm(" sync"); + count++; + } + + if (bits == 10) { + printf ("10 bit I2C addressing not yet implemented\n"); + return (0xff); + } + + return (0); +} + +static uchar i2c_get_data (uchar * return_data, int len) +{ + + unsigned int data, status; + int count = 0; + + DP (puts ("i2c_get_data\n")); + + while (len) { + + RESET_REG_BITS (I2C_CONTROL, BIT3); + asm(" sync"); + + /* Get and return the data */ + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + while ((status & 0xff) != 0x50) { + if (count > 20) { +#ifdef DEBUG_I2C + printf ("Failed to get data len status: 0x%02x\n", status); +#endif + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + asm(" sync"); + return 0; + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + } + GT_REG_READ (I2C_DATA, &data); + len--; + *return_data = (uchar) data; + return_data++; + + } + RESET_REG_BITS (I2C_CONTROL, BIT2 | BIT3); + asm(" sync"); + count = 0; + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + while ((status & 0xff) != 0x58) { + if (count > 2000) { + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + return (status); + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + } + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /* stop */ + asm(" sync"); + RESET_REG_BITS (I2C_CONTROL, (0x1 << 3)); + asm(" sync"); + + return (0); +} + + +static uchar i2c_write_data (unsigned int *data, int len) +{ + unsigned int status; + int count; + unsigned int temp; + unsigned int *temp_ptr = data; + + DP (puts ("i2c_write_data\n")); + + while (len) { + count = 0; + temp = (unsigned int) (*temp_ptr); + GT_REG_WRITE (I2C_DATA, temp); + asm(" sync"); + RESET_REG_BITS (I2C_CONTROL, (0x1 << 3)); + asm(" sync"); + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + while ((status & 0xff) != 0x28) { + if (count > 200) { + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + asm(" sync"); + return (status); + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + } + len--; + temp_ptr++; + } + return (0); +} + + +static uchar i2c_write_byte (unsigned char *data, int len) +{ + unsigned int status; + int count; + unsigned int temp; + unsigned char *temp_ptr = data; + + DP (puts ("i2c_write_byte\n")); + + while (len) { + count = 0; + /* Set and assert the data */ + temp = *temp_ptr; + GT_REG_WRITE (I2C_DATA, temp); + asm(" sync"); + RESET_REG_BITS (I2C_CONTROL, (0x1 << 3)); + asm(" sync"); + + + GT_REG_READ (I2C_CONTROL, &status); + while ((status & 0x08) != 0x08) { + GT_REG_READ (I2C_CONTROL, &status); + } + + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + while ((status & 0xff) != 0x28) { + if (count > 200) { + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */ + asm(" sync"); + return (status); + } + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status); + count++; + } + len--; + temp_ptr++; + } + return (0); +} + +static uchar +i2c_set_dev_offset (uchar dev_addr, unsigned int offset, int ten_bit, + int alen) +{ + uchar status; + unsigned int table[2]; + + table[1] = (offset ) & 0x0ff; /* low byte */ + table[0] = (offset >> 8) & 0x0ff; /* high byte */ + + DP (puts ("i2c_set_dev_offset\n")); + + status = i2c_select_device (dev_addr, 0, ten_bit); + if (status) { +#ifdef DEBUG_I2C +22 printf ("Failed to select device setting offset: 0x%02x\n", + status); +#endif + return status; + } +/* check the address offset length */ + if (alen == 0) + /* no address offset */ + return (0); + else if (alen == 1) { + /* 1 byte address offset */ + status = i2c_write_data (&offset, 1); + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to write data: 0x%02x\n", status); +#endif + return status; + } + } else if (alen == 2) { + /* 2 bytes address offset */ + status = i2c_write_data (table, 2); + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to write data: 0x%02x\n", status); +#endif + return status; + } + } else { + /* address offset unknown or not supported */ + printf ("Address length offset %d is not supported\n", alen); + return 1; + } + return 0; /* sucessful completion */ +} + +uchar +i2c_read (uchar dev_addr, unsigned int offset, int alen, uchar * data, + int len) +{ + uchar status = 0; + unsigned int i2cFreq = CFG_I2C_SPEED; + + DP (puts ("i2c_read\n")); + + i2c_init (i2cFreq, 0); /* set the i2c frequency */ + + status = i2c_set_dev_offset (dev_addr, offset, 0, alen); /* send the slave address + offset */ + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to set slave address & offset: 0x%02x\n", + status); +#endif + return status; + } + + status = i2c_select_device (dev_addr, 1, 0); + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to select device for data read: 0x%02x\n", + status); +#endif + return status; + } + + status = i2c_get_data (data, len); + if (status) { +#ifdef DEBUG_I2C + printf ("Data not read: 0x%02x\n", status); +#endif + return status; + } + + return 0; +} + + +void i2c_stop (void) +{ + GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); + asm(" sync"); +} + + +uchar +i2c_write (uchar dev_addr, unsigned int offset, int alen, uchar * data, + int len) +{ + uchar status = 0; + unsigned int i2cFreq = CFG_I2C_SPEED; + + DP (puts ("i2c_write\n")); + + i2c_init (i2cFreq, 0); /* set the i2c frequency */ + + status = i2c_set_dev_offset (dev_addr, offset, 0, alen); /* send the slave address + offset */ + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to set slave address & offset: 0x%02x\n", + status); +#endif + return status; + } + + + status = i2c_write_byte (data, len); /* write the data */ + if (status) { +#ifdef DEBUG_I2C + printf ("Data not written: 0x%02x\n", status); +#endif + return status; + } + /* issue a stop bit */ + i2c_stop (); + return 0; +} + + +int i2c_probe (uchar chip) +{ + +#ifdef DEBUG_I2C + unsigned int i2c_status; +#endif + uchar status = 0; + unsigned int i2cFreq = CFG_I2C_SPEED; + + DP (puts ("i2c_probe\n")); + + i2c_init (i2cFreq, 0); /* set the i2c frequency */ + + status = i2c_set_dev_offset (chip, 0, 0, 0); /* send the slave address + no offset */ + if (status) { +#ifdef DEBUG_I2C + printf ("Failed to set slave address: 0x%02x\n", status); +#endif + return (int) status; + } +#ifdef DEBUG_I2C + GT_REG_READ (I2C_STATUS_BAUDE_RATE, &i2c_status); + printf ("address %#x returned %#x\n", chip, i2c_status); +#endif + /* issue a stop bit */ + i2c_stop (); + return 0; /* successful completion */ +} |