| /* |
| * (C) Copyright 2003 |
| * 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 |
| */ |
| |
| #include <common.h> |
| |
| #ifdef CONFIG_HARD_I2C |
| |
| #include <mpc5xxx.h> |
| #include <i2c.h> |
| |
| #ifdef CFG_I2C_MODULE |
| #define I2C_BASE MPC5XXX_I2C2 |
| #else |
| #define I2C_BASE MPC5XXX_I2C1 |
| #endif |
| |
| #define I2C_TIMEOUT 100 |
| #define I2C_RETRIES 3 |
| |
| 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_reg_in(volatile u32 *reg) |
| { |
| return *reg >> 24; |
| __asm__ __volatile__ ("eieio"); |
| } |
| |
| 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) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| int timeout = I2C_TIMEOUT; |
| int status; |
| |
| status = mpc_reg_in(®s->msr); |
| |
| while (timeout-- && (status & I2C_BB)) { |
| #if 1 |
| 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); |
| #endif |
| udelay(1000); |
| status = mpc_reg_in(®s->msr); |
| } |
| |
| return (status & I2C_BB); |
| } |
| |
| static int wait_for_pin(int *status) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| |
| mpc_reg_out(®s->mcr, 0, 0); |
| mpc_reg_out(®s->madr, saddr << 1, 0); |
| |
| /* Set clock |
| */ |
| mpc_reg_out(®s->mfdr, speed, 0); |
| |
| /* Enable module |
| */ |
| mpc_reg_out(®s->mcr, I2C_EN, I2C_INIT_MASK); |
| mpc_reg_out(®s->msr, 0, I2C_IF); |
| |
| return; |
| } |
| |
| int i2c_probe(uchar chip) |
| { |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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); |
| 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) |
| { |
| uchar xaddr[4]; |
| struct mpc5xxx_i2c * regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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, 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) |
| { |
| uchar xaddr[4]; |
| struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE; |
| 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, 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) |
| { |
| char 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; |
| } |
| |
| #endif /* CONFIG_HARD_I2C */ |