diff options
Diffstat (limited to 'arch/powerpc/cpu/mpc8220/i2c.c')
-rw-r--r-- | arch/powerpc/cpu/mpc8220/i2c.c | 388 |
1 files changed, 0 insertions, 388 deletions
diff --git a/arch/powerpc/cpu/mpc8220/i2c.c b/arch/powerpc/cpu/mpc8220/i2c.c deleted file mode 100644 index 2f35d20..0000000 --- a/arch/powerpc/cpu/mpc8220/i2c.c +++ /dev/null @@ -1,388 +0,0 @@ -/* - * (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 */ |