+++ /dev/null
-/*
- * (C) Copyright 2004, Freescale, Inc
- * TsiChung Liew, Tsi-Chung.Liew@freescale.com.
- *
- * 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
- */
-
-#include <common.h>
-
-DECLARE_GLOBAL_DATA_PTR;
-
-#ifdef CONFIG_HARD_I2C
-
-#include <mpc8220.h>
-#include <i2c.h>
-
-typedef struct mpc8220_i2c {
- volatile u32 adr; /* I2Cn + 0x00 */
- volatile u32 fdr; /* I2Cn + 0x04 */
- volatile u32 cr; /* I2Cn + 0x08 */
- volatile u32 sr; /* I2Cn + 0x0C */
- volatile u32 dr; /* I2Cn + 0x10 */
-} i2c_t;
-
-/* I2Cn control register bits */
-#define I2C_EN 0x80
-#define I2C_IEN 0x40
-#define I2C_STA 0x20
-#define I2C_TX 0x10
-#define I2C_TXAK 0x08
-#define I2C_RSTA 0x04
-#define I2C_INIT_MASK (I2C_EN | I2C_STA | I2C_TX | I2C_RSTA)
-
-/* I2Cn status register bits */
-#define I2C_CF 0x80
-#define I2C_AAS 0x40
-#define I2C_BB 0x20
-#define I2C_AL 0x10
-#define I2C_SRW 0x04
-#define I2C_IF 0x02
-#define I2C_RXAK 0x01
-
-#define I2C_TIMEOUT 100
-#define I2C_RETRIES 1
-
-struct mpc8220_i2c_tap {
- int scl2tap;
- int tap2tap;
-};
-
-static int mpc_reg_in (volatile u32 * reg);
-static void mpc_reg_out (volatile u32 * reg, int val, int mask);
-static int wait_for_bb (void);
-static int wait_for_pin (int *status);
-static int do_address (uchar chip, char rdwr_flag);
-static int send_bytes (uchar chip, char *buf, int len);
-static int receive_bytes (uchar chip, char *buf, int len);
-static int mpc_get_fdr (int);
-
-static int mpc_reg_in (volatile u32 * reg)
-{
- int ret;
- ret = *reg >> 24;
- __asm__ __volatile__ ("eieio");
- return ret;
-}
-
-static void mpc_reg_out (volatile u32 * reg, int val, int mask)
-{
- int tmp;
-
- if (!mask) {
- *reg = val << 24;
- } else {
- tmp = mpc_reg_in (reg);
- *reg = ((tmp & ~mask) | (val & mask)) << 24;
- }
- __asm__ __volatile__ ("eieio");
-
- return;
-}
-
-static int wait_for_bb (void)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int timeout = I2C_TIMEOUT;
- int status;
-
- status = mpc_reg_in (®s->sr);
-
- while (timeout-- && (status & I2C_BB)) {
-
- mpc_reg_out (®s->cr, I2C_STA, I2C_STA);
- (void)mpc_reg_in (®s->dr);
- mpc_reg_out (®s->cr, 0, I2C_STA);
- mpc_reg_out (®s->cr, 0, 0);
- mpc_reg_out (®s->cr, I2C_EN, 0);
-
- udelay (1000);
- status = mpc_reg_in (®s->sr);
- }
-
- return (status & I2C_BB);
-}
-
-static int wait_for_pin (int *status)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int timeout = I2C_TIMEOUT;
-
- *status = mpc_reg_in (®s->sr);
-
- while (timeout-- && !(*status & I2C_IF)) {
- udelay (1000);
- *status = mpc_reg_in (®s->sr);
- }
-
- if (!(*status & I2C_IF)) {
- return -1;
- }
-
- mpc_reg_out (®s->sr, 0, I2C_IF);
- return 0;
-}
-
-static int do_address (uchar chip, char rdwr_flag)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int status;
-
- chip <<= 1;
-
- if (rdwr_flag)
- chip |= 1;
-
- mpc_reg_out (®s->cr, I2C_TX, I2C_TX);
- mpc_reg_out (®s->dr, chip, 0);
-
- if (wait_for_pin (&status))
- return -2;
- if (status & I2C_RXAK)
- return -3;
- return 0;
-}
-
-static int send_bytes (uchar chip, char *buf, int len)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int wrcount;
- int status;
-
- for (wrcount = 0; wrcount < len; ++wrcount) {
-
- mpc_reg_out (®s->dr, buf[wrcount], 0);
-
- if (wait_for_pin (&status))
- break;
-
- if (status & I2C_RXAK)
- break;
-
- }
-
- return !(wrcount == len);
- return 0;
-}
-
-static int receive_bytes (uchar chip, char *buf, int len)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int dummy = 1;
- int rdcount = 0;
- int status;
- int i;
-
- mpc_reg_out (®s->cr, 0, I2C_TX);
-
- for (i = 0; i < len; ++i) {
- buf[rdcount] = mpc_reg_in (®s->dr);
-
- if (dummy)
- dummy = 0;
- else
- rdcount++;
-
- if (wait_for_pin (&status))
- return -4;
- }
-
- mpc_reg_out (®s->cr, I2C_TXAK, I2C_TXAK);
- buf[rdcount++] = mpc_reg_in (®s->dr);
-
- if (wait_for_pin (&status))
- return -5;
-
- mpc_reg_out (®s->cr, 0, I2C_TXAK);
- return 0;
-}
-
-/**************** I2C API ****************/
-
-void i2c_init (int speed, int saddr)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
-
- mpc_reg_out (®s->cr, 0, 0);
- mpc_reg_out (®s->adr, saddr << 1, 0);
-
- /* Set clock
- */
- mpc_reg_out (®s->fdr, mpc_get_fdr (speed), 0);
-
- /* Enable module
- */
- mpc_reg_out (®s->cr, I2C_EN, I2C_INIT_MASK);
- mpc_reg_out (®s->sr, 0, I2C_IF);
- return;
-}
-
-static int mpc_get_fdr (int speed)
-{
- static int fdr = -1;
-
- if (fdr == -1) {
- ulong best_speed = 0;
- ulong divider;
- ulong ipb, scl;
- ulong bestmatch = 0xffffffffUL;
- int best_i = 0, best_j = 0, i, j;
- int SCL_Tap[] = { 9, 10, 12, 15, 5, 6, 7, 8 };
- struct mpc8220_i2c_tap scltap[] = {
- {4, 1},
- {4, 2},
- {6, 4},
- {6, 8},
- {14, 16},
- {30, 32},
- {62, 64},
- {126, 128}
- };
-
- ipb = gd->bus_clk;
- for (i = 7; i >= 0; i--) {
- for (j = 7; j >= 0; j--) {
- scl = 2 * (scltap[j].scl2tap +
- (SCL_Tap[i] -
- 1) * scltap[j].tap2tap + 2);
- if (ipb <= speed * scl) {
- if ((speed * scl - ipb) < bestmatch) {
- bestmatch = speed * scl - ipb;
- best_i = i;
- best_j = j;
- best_speed = ipb / scl;
- }
- }
- }
- }
- divider = (best_i & 3) | ((best_i & 4) << 3) | (best_j << 2);
- if (gd->flags & GD_FLG_RELOC) {
- fdr = divider;
- } else {
- printf ("%ld kHz, ", best_speed / 1000);
- return divider;
- }
- }
-
- return fdr;
-}
-
-int i2c_probe (uchar chip)
-{
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int i;
-
- for (i = 0; i < I2C_RETRIES; i++) {
- mpc_reg_out (®s->cr, I2C_STA, I2C_STA);
-
- if (!do_address (chip, 0)) {
- mpc_reg_out (®s->cr, 0, I2C_STA);
- break;
- }
-
- mpc_reg_out (®s->cr, 0, I2C_STA);
- udelay (50);
- }
-
- return (i == I2C_RETRIES);
-}
-
-int i2c_read (uchar chip, uint addr, int alen, uchar * buf, int len)
-{
- uchar xaddr[4];
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int ret = -1;
-
- xaddr[0] = (addr >> 24) & 0xFF;
- xaddr[1] = (addr >> 16) & 0xFF;
- xaddr[2] = (addr >> 8) & 0xFF;
- xaddr[3] = addr & 0xFF;
-
- if (wait_for_bb ()) {
- printf ("i2c_read: bus is busy\n");
- goto Done;
- }
-
- mpc_reg_out (®s->cr, I2C_STA, I2C_STA);
- if (do_address (chip, 0)) {
- printf ("i2c_read: failed to address chip\n");
- goto Done;
- }
-
- if (send_bytes (chip, (char *)&xaddr[4 - alen], alen)) {
- printf ("i2c_read: send_bytes failed\n");
- goto Done;
- }
-
- mpc_reg_out (®s->cr, I2C_RSTA, I2C_RSTA);
- if (do_address (chip, 1)) {
- printf ("i2c_read: failed to address chip\n");
- goto Done;
- }
-
- if (receive_bytes (chip, (char *)buf, len)) {
- printf ("i2c_read: receive_bytes failed\n");
- goto Done;
- }
-
- ret = 0;
- Done:
- mpc_reg_out (®s->cr, 0, I2C_STA);
- return ret;
-}
-
-int i2c_write (uchar chip, uint addr, int alen, uchar * buf, int len)
-{
- uchar xaddr[4];
- i2c_t *regs = (i2c_t *) MMAP_I2C;
- int ret = -1;
-
- xaddr[0] = (addr >> 24) & 0xFF;
- xaddr[1] = (addr >> 16) & 0xFF;
- xaddr[2] = (addr >> 8) & 0xFF;
- xaddr[3] = addr & 0xFF;
-
- if (wait_for_bb ()) {
- printf ("i2c_write: bus is busy\n");
- goto Done;
- }
-
- mpc_reg_out (®s->cr, I2C_STA, I2C_STA);
- if (do_address (chip, 0)) {
- printf ("i2c_write: failed to address chip\n");
- goto Done;
- }
-
- if (send_bytes (chip, (char *)&xaddr[4 - alen], alen)) {
- printf ("i2c_write: send_bytes failed\n");
- goto Done;
- }
-
- if (send_bytes (chip, (char *)buf, len)) {
- printf ("i2c_write: send_bytes failed\n");
- goto Done;
- }
-
- ret = 0;
- Done:
- mpc_reg_out (®s->cr, 0, I2C_STA);
- return ret;
-}
-
-#endif /* CONFIG_HARD_I2C */
projects / karo-tx-uboot.git / blobdiff