| /* |
| * (C) Copyright 2003 - 2007 |
| * 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 |
| * |
| * Based on the MPC5xxx code. |
| */ |
| |
| #include <common.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| #ifdef CONFIG_HARD_I2C |
| |
| #include <mpc512x.h> |
| #include <i2c.h> |
| |
| #define immr ((immap_t *)CFG_IMMR) |
| |
| /* by default set I2C bus 0 active */ |
| static unsigned int bus_num = 0; |
| |
| #define I2C_TIMEOUT 100 |
| #define I2C_RETRIES 3 |
| |
| struct mpc512x_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 = *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) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int timeout = I2C_TIMEOUT; |
| int status; |
| |
| status = mpc_reg_in (®s->msr); |
| |
| while (timeout-- && (status & I2C_BB)) { |
| volatile int temp; |
| mpc_reg_out (®s->mcr, I2C_STA, I2C_STA); |
| temp = mpc_reg_in (®s->mdr); |
| mpc_reg_out (®s->mcr, 0, I2C_STA); |
| mpc_reg_out (®s->mcr, 0, 0); |
| mpc_reg_out (®s->mcr, I2C_EN, 0); |
| |
| udelay (1000); |
| status = mpc_reg_in (®s->msr); |
| } |
| |
| return (status & I2C_BB); |
| } |
| |
| static int wait_for_pin (int *status) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int timeout = I2C_TIMEOUT; |
| |
| *status = mpc_reg_in (®s->msr); |
| |
| while (timeout-- && !(*status & I2C_IF)) { |
| udelay (1000); |
| *status = mpc_reg_in (®s->msr); |
| } |
| |
| if (!(*status & I2C_IF)) { |
| return -1; |
| } |
| |
| mpc_reg_out (®s->msr, 0, I2C_IF); |
| |
| return 0; |
| } |
| |
| static int do_address (uchar chip, char rdwr_flag) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int status; |
| |
| chip <<= 1; |
| |
| if (rdwr_flag) { |
| chip |= 1; |
| } |
| |
| mpc_reg_out (®s->mcr, I2C_TX, I2C_TX); |
| mpc_reg_out (®s->mdr, 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) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int wrcount; |
| int status; |
| |
| for (wrcount = 0; wrcount < len; ++wrcount) { |
| |
| mpc_reg_out (®s->mdr, buf[wrcount], 0); |
| |
| if (wait_for_pin (&status)) { |
| break; |
| } |
| |
| if (status & I2C_RXAK) { |
| break; |
| } |
| |
| } |
| |
| return !(wrcount == len); |
| } |
| |
| static int receive_bytes (uchar chip, char *buf, int len) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int dummy = 1; |
| int rdcount = 0; |
| int status; |
| int i; |
| |
| mpc_reg_out (®s->mcr, 0, I2C_TX); |
| |
| for (i = 0; i < len; ++i) { |
| buf[rdcount] = mpc_reg_in (®s->mdr); |
| |
| if (dummy) { |
| dummy = 0; |
| } else { |
| rdcount++; |
| } |
| |
| if (wait_for_pin (&status)) { |
| return -4; |
| } |
| } |
| |
| mpc_reg_out (®s->mcr, I2C_TXAK, I2C_TXAK); |
| buf[rdcount++] = mpc_reg_in (®s->mdr); |
| |
| if (wait_for_pin (&status)) { |
| return -5; |
| } |
| |
| mpc_reg_out (®s->mcr, 0, I2C_TXAK); |
| |
| return 0; |
| } |
| |
| /**************** I2C API ****************/ |
| |
| void i2c_init (int speed, int saddr) |
| { |
| int i; |
| for(i = 0; i < I2C_BUS_CNT; i++){ |
| i2c512x_dev_t *regs = &immr->i2c.dev[i]; |
| mpc_reg_out (®s->mcr, 0, 0); |
| |
| /* Set clock */ |
| mpc_reg_out (®s->mfdr, mpc_get_fdr (speed), 0); |
| mpc_reg_out (®s->madr, saddr << 1, 0); |
| |
| /* Enable module */ |
| mpc_reg_out (®s->mcr, I2C_EN, I2C_INIT_MASK); |
| mpc_reg_out (®s->msr, 0, I2C_IF); |
| } |
| |
| /* Disable interrupts */ |
| immr->i2c.icr = 0; |
| /* Turn off filters */ |
| immr->i2c.mifr = 0; |
| 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 mpc512x_i2c_tap scltap[] = { |
| {4, 1}, |
| {4, 2}, |
| {6, 4}, |
| {6, 8}, |
| {14, 16}, |
| {30, 32}, |
| {62, 64}, |
| {126, 128} |
| }; |
| |
| ipb = gd->ipb_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 { |
| debug("%ld kHz, \n", best_speed / 1000); |
| return divider; |
| } |
| } |
| |
| return fdr; |
| } |
| |
| int i2c_probe (uchar chip) |
| { |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| int i; |
| |
| for (i = 0; i < I2C_RETRIES; i++) { |
| mpc_reg_out (®s->mcr, I2C_STA, I2C_STA); |
| |
| if (! do_address (chip, 0)) { |
| mpc_reg_out (®s->mcr, 0, I2C_STA); |
| udelay (500); |
| break; |
| } |
| |
| mpc_reg_out (®s->mcr, 0, I2C_STA); |
| udelay (500); |
| } |
| |
| return (i == I2C_RETRIES); |
| } |
| |
| int i2c_read (uchar chip, uint addr, int alen, uchar *buf, int len) |
| { |
| char xaddr[4]; |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| 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->mcr, I2C_STA, I2C_STA); |
| if (do_address (chip, 0)) { |
| printf ("i2c_read: failed to address chip\n"); |
| goto Done; |
| } |
| |
| if (send_bytes (chip, &xaddr[4-alen], alen)) { |
| printf ("i2c_read: send_bytes failed\n"); |
| goto Done; |
| } |
| |
| mpc_reg_out (®s->mcr, 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->mcr, 0, I2C_STA); |
| return ret; |
| } |
| |
| int i2c_write (uchar chip, uint addr, int alen, uchar *buf, int len) |
| { |
| char xaddr[4]; |
| i2c512x_dev_t *regs = &immr->i2c.dev[bus_num]; |
| 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->mcr, I2C_STA, I2C_STA); |
| if (do_address (chip, 0)) { |
| printf ("i2c_write: failed to address chip\n"); |
| goto Done; |
| } |
| |
| if (send_bytes (chip, &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->mcr, 0, I2C_STA); |
| return ret; |
| } |
| |
| uchar i2c_reg_read (uchar chip, uchar reg) |
| { |
| uchar buf; |
| |
| i2c_read (chip, reg, 1, &buf, 1); |
| |
| return buf; |
| } |
| |
| void i2c_reg_write (uchar chip, uchar reg, uchar val) |
| { |
| i2c_write (chip, reg, 1, &val, 1); |
| |
| return; |
| } |
| |
| |
| int i2c_set_bus_num (unsigned int bus) |
| { |
| if (bus >= I2C_BUS_CNT) { |
| return -1; |
| } |
| bus_num = bus; |
| |
| return 0; |
| } |
| |
| unsigned int i2c_get_bus_num (void) |
| { |
| return bus_num; |
| } |
| |
| /* TODO */ |
| unsigned int i2c_get_bus_speed (void) |
| { |
| return -1; |
| } |
| |
| int i2c_set_bus_speed (unsigned int speed) |
| { |
| if (speed != CFG_I2C_SPEED) |
| return -1; |
| |
| return 0; |
| } |
| |
| #endif /* CONFIG_HARD_I2C */ |
