diff options
| -rw-r--r-- | drivers/i2c/bfin-twi_i2c.c | 169 |
1 files changed, 108 insertions, 61 deletions
diff --git a/drivers/i2c/bfin-twi_i2c.c b/drivers/i2c/bfin-twi_i2c.c index 73a78d2..b3a04d3 100644 --- a/drivers/i2c/bfin-twi_i2c.c +++ b/drivers/i2c/bfin-twi_i2c.c @@ -1,7 +1,7 @@ /* * i2c.c - driver for Blackfin on-chip TWI/I2C * - * Copyright (c) 2006-2008 Analog Devices Inc. + * Copyright (c) 2006-2010 Analog Devices Inc. * * Licensed under the GPL-2 or later. */ @@ -12,6 +12,35 @@ #include <asm/blackfin.h> #include <asm/mach-common/bits/twi.h> +/* Every register is 32bit aligned, but only 16bits in size */ +#define ureg(name) u16 name; u16 __pad_##name; +struct twi_regs { + ureg(clkdiv); + ureg(control); + ureg(slave_ctl); + ureg(slave_stat); + ureg(slave_addr); + ureg(master_ctl); + ureg(master_stat); + ureg(master_addr); + ureg(int_stat); + ureg(int_mask); + ureg(fifo_ctl); + ureg(fifo_stat); + char __pad[0x50]; + ureg(xmt_data8); + ureg(xmt_data16); + ureg(rcv_data8); + ureg(rcv_data16); +}; +#undef ureg + +/* U-Boot I2C framework allows only one active device at a time. */ +#ifdef TWI_CLKDIV +#define TWI0_CLKDIV TWI_CLKDIV +#endif +static volatile struct twi_regs *twi = (void *)TWI0_CLKDIV; + #ifdef DEBUG # define dmemset(s, c, n) memset(s, c, n) #else @@ -19,29 +48,10 @@ #endif #define debugi(fmt, args...) \ debug( \ - "MSTAT:0x%03x FSTAT:0x%x ISTAT:0x%02x\t" \ - "%-20s:%-3i: " fmt "\n", \ - bfin_read_TWI_MASTER_STAT(), bfin_read_TWI_FIFO_STAT(), bfin_read_TWI_INT_STAT(), \ + "MSTAT:0x%03x FSTAT:0x%x ISTAT:0x%02x\t%-20s:%-3i: " fmt "\n", \ + twi->master_stat, twi->fifo_stat, twi->int_stat, \ __func__, __LINE__, ## args) -#ifdef TWI0_CLKDIV -#define bfin_write_TWI_CLKDIV(val) bfin_write_TWI0_CLKDIV(val) -#define bfin_read_TWI_CLKDIV(val) bfin_read_TWI0_CLKDIV(val) -#define bfin_write_TWI_CONTROL(val) bfin_write_TWI0_CONTROL(val) -#define bfin_read_TWI_CONTROL(val) bfin_read_TWI0_CONTROL(val) -#define bfin_write_TWI_MASTER_ADDR(val) bfin_write_TWI0_MASTER_ADDR(val) -#define bfin_write_TWI_XMT_DATA8(val) bfin_write_TWI0_XMT_DATA8(val) -#define bfin_read_TWI_RCV_DATA8() bfin_read_TWI0_RCV_DATA8() -#define bfin_read_TWI_INT_STAT() bfin_read_TWI0_INT_STAT() -#define bfin_write_TWI_INT_STAT(val) bfin_write_TWI0_INT_STAT(val) -#define bfin_read_TWI_MASTER_STAT() bfin_read_TWI0_MASTER_STAT() -#define bfin_write_TWI_MASTER_STAT(val) bfin_write_TWI0_MASTER_STAT(val) -#define bfin_read_TWI_MASTER_CTL() bfin_read_TWI0_MASTER_CTL() -#define bfin_write_TWI_MASTER_CTL(val) bfin_write_TWI0_MASTER_CTL(val) -#define bfin_write_TWI_INT_MASK(val) bfin_write_TWI0_INT_MASK(val) -#define bfin_write_TWI_FIFO_CTL(val) bfin_write_TWI0_FIFO_CTL(val) -#endif - #ifdef CONFIG_TWICLK_KHZ # error do not define CONFIG_TWICLK_KHZ ... use CONFIG_SYS_I2C_SPEED #endif @@ -87,49 +97,48 @@ static int wait_for_completion(struct i2c_msg *msg) ulong timebase = get_timer(0); do { - int_stat = bfin_read_TWI_INT_STAT(); + int_stat = twi->int_stat; if (int_stat & XMTSERV) { debugi("processing XMTSERV"); - bfin_write_TWI_INT_STAT(XMTSERV); + twi->int_stat = XMTSERV; SSYNC(); if (msg->alen) { - bfin_write_TWI_XMT_DATA8(*(msg->abuf++)); + twi->xmt_data8 = *(msg->abuf++); --msg->alen; } else if (!(msg->flags & I2C_M_COMBO) && msg->len) { - bfin_write_TWI_XMT_DATA8(*(msg->buf++)); + twi->xmt_data8 = *(msg->buf++); --msg->len; } else { - bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | - (msg->flags & I2C_M_COMBO ? RSTART | MDIR : STOP)); + twi->master_ctl |= (msg->flags & I2C_M_COMBO) ? RSTART | MDIR : STOP; SSYNC(); } } if (int_stat & RCVSERV) { debugi("processing RCVSERV"); - bfin_write_TWI_INT_STAT(RCVSERV); + twi->int_stat = RCVSERV; SSYNC(); if (msg->len) { - *(msg->buf++) = bfin_read_TWI_RCV_DATA8(); + *(msg->buf++) = twi->rcv_data8; --msg->len; } else if (msg->flags & I2C_M_STOP) { - bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() | STOP); + twi->master_ctl |= STOP; SSYNC(); } } if (int_stat & MERR) { debugi("processing MERR"); - bfin_write_TWI_INT_STAT(MERR); + twi->int_stat = MERR; SSYNC(); return msg->len; } if (int_stat & MCOMP) { debugi("processing MCOMP"); - bfin_write_TWI_INT_STAT(MCOMP); + twi->int_stat = MCOMP; SSYNC(); if (msg->flags & I2C_M_COMBO && msg->len) { - bfin_write_TWI_MASTER_CTL((bfin_read_TWI_MASTER_CTL() & ~RSTART) | - (min(msg->len, 0xff) << 6) | MEN | MDIR); + twi->master_ctl = (twi->master_ctl & ~RSTART) | + (min(msg->len, 0xff) << 6) | MEN | MDIR; SSYNC(); } else break; @@ -172,55 +181,54 @@ static int i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer, int len, chip, addr, alen, buffer[0], len, flags, (flags & I2C_M_READ ? "rd" : "wr")); /* wait for things to settle */ - while (bfin_read_TWI_MASTER_STAT() & BUSBUSY) + while (twi->master_stat & BUSBUSY) if (ctrlc()) return 1; /* Set Transmit device address */ - bfin_write_TWI_MASTER_ADDR(chip); + twi->master_addr = chip; /* Clear the FIFO before starting things */ - bfin_write_TWI_FIFO_CTL(XMTFLUSH | RCVFLUSH); + twi->fifo_ctl = XMTFLUSH | RCVFLUSH; SSYNC(); - bfin_write_TWI_FIFO_CTL(0); + twi->fifo_ctl = 0; SSYNC(); /* prime the pump */ if (msg.alen) { len = (msg.flags & I2C_M_COMBO) ? msg.alen : msg.alen + len; debugi("first byte=0x%02x", *msg.abuf); - bfin_write_TWI_XMT_DATA8(*(msg.abuf++)); + twi->xmt_data8 = *(msg.abuf++); --msg.alen; } else if (!(msg.flags & I2C_M_READ) && msg.len) { debugi("first byte=0x%02x", *msg.buf); - bfin_write_TWI_XMT_DATA8(*(msg.buf++)); + twi->xmt_data8 = *(msg.buf++); --msg.len; } /* clear int stat */ - bfin_write_TWI_MASTER_STAT(-1); - bfin_write_TWI_INT_STAT(-1); - bfin_write_TWI_INT_MASK(0); + twi->master_stat = -1; + twi->int_stat = -1; + twi->int_mask = 0; SSYNC(); /* Master enable */ - bfin_write_TWI_MASTER_CTL( - (bfin_read_TWI_MASTER_CTL() & FAST) | + twi->master_ctl = + (twi->master_ctl & FAST) | (min(len, 0xff) << 6) | MEN | - ((msg.flags & I2C_M_READ) ? MDIR : 0) - ); + ((msg.flags & I2C_M_READ) ? MDIR : 0); SSYNC(); - debugi("CTL=0x%04x", bfin_read_TWI_MASTER_CTL()); + debugi("CTL=0x%04x", twi->master_ctl); /* process the rest */ ret = wait_for_completion(&msg); debugi("ret=%d", ret); if (ret) { - bfin_write_TWI_MASTER_CTL(bfin_read_TWI_MASTER_CTL() & ~MEN); - bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() & ~TWI_ENA); + twi->master_ctl &= ~MEN; + twi->control &= ~TWI_ENA; SSYNC(); - bfin_write_TWI_CONTROL(bfin_read_TWI_CONTROL() | TWI_ENA); + twi->control |= TWI_ENA; SSYNC(); } @@ -238,10 +246,10 @@ int i2c_set_bus_speed(unsigned int speed) /* Set TWI interface clock */ if (clkdiv < I2C_DUTY_MAX || clkdiv > I2C_DUTY_MIN) return -1; - bfin_write_TWI_CLKDIV((clkdiv << 8) | (clkdiv & 0xff)); + twi->clkdiv = (clkdiv << 8) | (clkdiv & 0xff); /* Don't turn it on */ - bfin_write_TWI_MASTER_CTL(speed > 100000 ? FAST : 0); + twi->master_ctl = (speed > 100000 ? FAST : 0); return 0; } @@ -253,7 +261,7 @@ int i2c_set_bus_speed(unsigned int speed) unsigned int i2c_get_bus_speed(void) { /* 10 MHz / (2 * CLKDIV) -> 5 MHz / CLKDIV */ - return 5000000 / (bfin_read_TWI_CLKDIV() & 0xff); + return 5000000 / (twi->clkdiv & 0xff); } /** @@ -269,24 +277,23 @@ void i2c_init(int speed, int slaveaddr) uint8_t prescale = ((get_sclk() / 1024 / 1024 + 5) / 10) & 0x7F; /* Set TWI internal clock as 10MHz */ - bfin_write_TWI_CONTROL(prescale); + twi->control = prescale; /* Set TWI interface clock as specified */ i2c_set_bus_speed(speed); /* Enable it */ - bfin_write_TWI_CONTROL(TWI_ENA | prescale); + twi->control = TWI_ENA | prescale; SSYNC(); - debugi("CONTROL:0x%04x CLKDIV:0x%04x", - bfin_read_TWI_CONTROL(), bfin_read_TWI_CLKDIV()); + debugi("CONTROL:0x%04x CLKDIV:0x%04x", twi->control, twi->clkdiv); #if CONFIG_SYS_I2C_SLAVE # error I2C slave support not tested/supported /* If they want us as a slave, do it */ if (slaveaddr) { - bfin_write_TWI_SLAVE_ADDR(slaveaddr); - bfin_write_TWI_SLAVE_CTL(SEN); + twi->slave_addr = slaveaddr; + twi->slave_ctl = SEN; } #endif } @@ -329,3 +336,43 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) { return i2c_transfer(chip, addr, alen, buffer, len, 0); } + +/** + * i2c_set_bus_num - change active I2C bus + * @bus: bus index, zero based + * @returns: 0 on success, non-0 on failure + */ +int i2c_set_bus_num(unsigned int bus) +{ + switch (bus) { +#if CONFIG_SYS_MAX_I2C_BUS > 0 + case 0: twi = (void *)TWI0_CLKDIV; return 0; +#endif +#if CONFIG_SYS_MAX_I2C_BUS > 1 + case 1: twi = (void *)TWI1_CLKDIV; return 0; +#endif +#if CONFIG_SYS_MAX_I2C_BUS > 2 + case 2: twi = (void *)TWI2_CLKDIV; return 0; +#endif + default: return -1; + } +} + +/** + * i2c_get_bus_num - returns index of active I2C bus + */ +unsigned int i2c_get_bus_num(void) +{ + switch ((unsigned long)twi) { +#if CONFIG_SYS_MAX_I2C_BUS > 0 + case TWI0_CLKDIV: return 0; +#endif +#if CONFIG_SYS_MAX_I2C_BUS > 1 + case TWI1_CLKDIV: return 1; +#endif +#if CONFIG_SYS_MAX_I2C_BUS > 2 + case TWI2_CLKDIV: return 2; +#endif + default: return -1; + } +} |