diff options
| -rw-r--r-- | drivers/i2c/adi_i2c.c | 151 |
1 files changed, 80 insertions, 71 deletions
diff --git a/drivers/i2c/adi_i2c.c b/drivers/i2c/adi_i2c.c index 743aa251a1..675f4171ce 100644 --- a/drivers/i2c/adi_i2c.c +++ b/drivers/i2c/adi_i2c.c @@ -1,7 +1,7 @@ /* - * i2c.c - driver for Blackfin on-chip TWI/I2C + * i2c.c - driver for ADI TWI/I2C * - * Copyright (c) 2006-2010 Analog Devices Inc. + * Copyright (c) 2006-2013 Analog Devices Inc. * * Licensed under the GPL-2 or later. */ @@ -11,6 +11,7 @@ #include <asm/clock.h> #include <asm/twi.h> +#include <asm/io.h> /* Every register is 32bit aligned, but only 16bits in size */ #define ureg(name) u16 name; u16 __pad_##name; @@ -39,7 +40,7 @@ struct twi_regs { #ifdef TWI_CLKDIV #define TWI0_CLKDIV TWI_CLKDIV #endif -static volatile struct twi_regs *twi = (void *)TWI0_CLKDIV; +static struct twi_regs *twi = (void *)TWI0_CLKDIV; #ifdef DEBUG # define dmemset(s, c, n) memset(s, c, n) @@ -93,53 +94,54 @@ struct i2c_msg { */ static int wait_for_completion(struct i2c_msg *msg) { - uint16_t int_stat; + u16 int_stat, ctl; ulong timebase = get_timer(0); do { - int_stat = twi->int_stat; + int_stat = readw(&twi->int_stat); if (int_stat & XMTSERV) { debugi("processing XMTSERV"); - twi->int_stat = XMTSERV; - SSYNC(); + writew(XMTSERV, &twi->int_stat); if (msg->alen) { - twi->xmt_data8 = *(msg->abuf++); + writew(*(msg->abuf++), &twi->xmt_data8); --msg->alen; } else if (!(msg->flags & I2C_M_COMBO) && msg->len) { - twi->xmt_data8 = *(msg->buf++); + writew(*(msg->buf++), &twi->xmt_data8); --msg->len; } else { - twi->master_ctl |= (msg->flags & I2C_M_COMBO) ? RSTART | MDIR : STOP; - SSYNC(); + ctl = readw(&twi->master_ctl); + if (msg->flags & I2C_M_COMBO) + writew(ctl | RSTART | MDIR, + &twi->master_ctl); + else + writew(ctl | STOP, &twi->master_ctl); } } if (int_stat & RCVSERV) { debugi("processing RCVSERV"); - twi->int_stat = RCVSERV; - SSYNC(); + writew(RCVSERV, &twi->int_stat); if (msg->len) { - *(msg->buf++) = twi->rcv_data8; + *(msg->buf++) = readw(&twi->rcv_data8); --msg->len; } else if (msg->flags & I2C_M_STOP) { - twi->master_ctl |= STOP; - SSYNC(); + ctl = readw(&twi->master_ctl); + writew(ctl | STOP, &twi->master_ctl); } } if (int_stat & MERR) { debugi("processing MERR"); - twi->int_stat = MERR; - SSYNC(); + writew(MERR, &twi->int_stat); return msg->len; } if (int_stat & MCOMP) { debugi("processing MCOMP"); - twi->int_stat = MCOMP; - SSYNC(); + writew(MCOMP, &twi->int_stat); if (msg->flags & I2C_M_COMBO && msg->len) { - twi->master_ctl = (twi->master_ctl & ~RSTART) | + ctl = readw(&twi->master_ctl); + ctl = (ctl & ~RSTART) | (min(msg->len, 0xff) << 6) | MEN | MDIR; - SSYNC(); + writew(ctl, &twi->master_ctl); } else break; } @@ -160,8 +162,11 @@ static int wait_for_completion(struct i2c_msg *msg) * Here we just get the i2c stuff all prepped and ready, and then tail off * into wait_for_completion() for all the bits to go. */ -static int i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer, int len, u8 flags) +static int i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer, + int len, u8 flags) { + int ret; + u16 ctl; uchar addr_buffer[] = { (addr >> 0), (addr >> 8), @@ -174,62 +179,59 @@ static int i2c_transfer(uchar chip, uint addr, int alen, uchar *buffer, int len, .abuf = addr_buffer, .alen = alen, }; - int ret; dmemset(buffer, 0xff, len); - debugi("chip=0x%x addr=0x%02x alen=%i buf[0]=0x%02x len=%i flags=0x%02x[%s] ", - chip, addr, alen, buffer[0], len, flags, (flags & I2C_M_READ ? "rd" : "wr")); + debugi("chip=0x%x addr=0x%02x alen=%i buf[0]=0x%02x len=%i ", + chip, addr, alen, buffer[0], len); + debugi("flags=0x%02x[%s] ", flags, + (flags & I2C_M_READ ? "rd" : "wr")); /* wait for things to settle */ - while (twi->master_stat & BUSBUSY) + while (readw(&twi->master_stat) & BUSBUSY) if (ctrlc()) return 1; /* Set Transmit device address */ - twi->master_addr = chip; + writew(chip, &twi->master_addr); /* Clear the FIFO before starting things */ - twi->fifo_ctl = XMTFLUSH | RCVFLUSH; - SSYNC(); - twi->fifo_ctl = 0; - SSYNC(); + writew(XMTFLUSH | RCVFLUSH, &twi->fifo_ctl); + writew(0, &twi->fifo_ctl); /* prime the pump */ if (msg.alen) { len = (msg.flags & I2C_M_COMBO) ? msg.alen : msg.alen + len; debugi("first byte=0x%02x", *msg.abuf); - twi->xmt_data8 = *(msg.abuf++); + writew(*(msg.abuf++), &twi->xmt_data8); --msg.alen; } else if (!(msg.flags & I2C_M_READ) && msg.len) { debugi("first byte=0x%02x", *msg.buf); - twi->xmt_data8 = *(msg.buf++); + writew(*(msg.buf++), &twi->xmt_data8); --msg.len; } /* clear int stat */ - twi->master_stat = -1; - twi->int_stat = -1; - twi->int_mask = 0; - SSYNC(); + writew(-1, &twi->master_stat); + writew(-1, &twi->int_stat); + writew(0, &twi->int_mask); /* Master enable */ - twi->master_ctl = - (twi->master_ctl & FAST) | - (min(len, 0xff) << 6) | MEN | - ((msg.flags & I2C_M_READ) ? MDIR : 0); - SSYNC(); - debugi("CTL=0x%04x", twi->master_ctl); + ctl = readw(&twi->master_ctl); + ctl = (ctl & FAST) | (min(len, 0xff) << 6) | MEN | + ((msg.flags & I2C_M_READ) ? MDIR : 0); + writew(ctl, &twi->master_ctl); /* process the rest */ ret = wait_for_completion(&msg); debugi("ret=%d", ret); if (ret) { - twi->master_ctl &= ~MEN; - twi->control &= ~TWI_ENA; - SSYNC(); - twi->control |= TWI_ENA; - SSYNC(); + ctl = readw(&twi->master_ctl) & ~MEN; + writew(ctl, &twi->master_ctl); + ctl = readw(&twi->control) & ~TWI_ENA; + writew(ctl, &twi->control); + ctl = readw(&twi->control) | TWI_ENA; + writew(ctl, &twi->control); } return ret; @@ -246,10 +248,11 @@ int i2c_set_bus_speed(unsigned int speed) /* Set TWI interface clock */ if (clkdiv < I2C_DUTY_MAX || clkdiv > I2C_DUTY_MIN) return -1; - twi->clkdiv = (clkdiv << 8) | (clkdiv & 0xff); + clkdiv = (clkdiv << 8) | (clkdiv & 0xff); + writew(clkdiv, &twi->clkdiv); /* Don't turn it on */ - twi->master_ctl = (speed > 100000 ? FAST : 0); + writew(speed > 100000 ? FAST : 0, &twi->master_ctl); return 0; } @@ -260,8 +263,9 @@ int i2c_set_bus_speed(unsigned int speed) */ unsigned int i2c_get_bus_speed(void) { + u16 clkdiv = readw(&twi->clkdiv) & 0xff; /* 10 MHz / (2 * CLKDIV) -> 5 MHz / CLKDIV */ - return 5000000 / (twi->clkdiv & 0xff); + return 5000000 / clkdiv; } /** @@ -274,27 +278,22 @@ unsigned int i2c_get_bus_speed(void) */ void i2c_init(int speed, int slaveaddr) { - uint8_t prescale = ((get_i2c_clk() / 1000 / 1000 + 5) / 10) & 0x7F; + u16 prescale = ((get_i2c_clk() / 1000 / 1000 + 5) / 10) & 0x7F; /* Set TWI internal clock as 10MHz */ - twi->control = prescale; + writew(prescale, &twi->control); /* Set TWI interface clock as specified */ i2c_set_bus_speed(speed); /* Enable it */ - twi->control = TWI_ENA | prescale; - SSYNC(); + writew(TWI_ENA | prescale, &twi->control); - debugi("CONTROL:0x%04x CLKDIV:0x%04x", twi->control, twi->clkdiv); + debugi("CONTROL:0x%04x CLKDIV:0x%04x", readw(&twi->control), + readw(&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) { - twi->slave_addr = slaveaddr; - twi->slave_ctl = SEN; - } #endif } @@ -320,7 +319,8 @@ int i2c_probe(uchar chip) */ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) { - return i2c_transfer(chip, addr, alen, buffer, len, (alen ? I2C_M_COMBO : I2C_M_READ)); + return i2c_transfer(chip, addr, alen, buffer, + len, (alen ? I2C_M_COMBO : I2C_M_READ)); } /** @@ -346,15 +346,21 @@ 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; + case 0: + twi = (void *)TWI0_CLKDIV; + return 0; #endif #if CONFIG_SYS_MAX_I2C_BUS > 1 - case 1: twi = (void *)TWI1_CLKDIV; return 0; + case 1: + twi = (void *)TWI1_CLKDIV; + return 0; #endif #if CONFIG_SYS_MAX_I2C_BUS > 2 - case 2: twi = (void *)TWI2_CLKDIV; return 0; + case 2: + twi = (void *)TWI2_CLKDIV; + return 0; #endif - default: return -1; + default: return -1; } } @@ -365,14 +371,17 @@ unsigned int i2c_get_bus_num(void) { switch ((unsigned long)twi) { #if CONFIG_SYS_MAX_I2C_BUS > 0 - case TWI0_CLKDIV: return 0; + case TWI0_CLKDIV: + return 0; #endif #if CONFIG_SYS_MAX_I2C_BUS > 1 - case TWI1_CLKDIV: return 1; + case TWI1_CLKDIV: + return 1; #endif #if CONFIG_SYS_MAX_I2C_BUS > 2 - case TWI2_CLKDIV: return 2; + case TWI2_CLKDIV: + return 2; #endif - default: return -1; + default: return -1; } } |