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-rw-r--r--drivers/i2c/adi_i2c.c151
1 files changed, 80 insertions, 71 deletions
diff --git a/drivers/i2c/adi_i2c.c b/drivers/i2c/adi_i2c.c
index 743aa25..675f417 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;
}
}
generated by cgit v1.1 at 2024-11-22 17:41:38 +0000