c1bce4fff7
This patch adds I2C mux support for the fsl_i2c driver. This allows you to add "new" i2c busses, which are reached over i2c muxes. For more infos, please look in the README and search for CONFIG_I2C_MUX. Signed-off-by: Heiko Schocher <hs@denx.de> Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
428 lines
11 KiB
C
428 lines
11 KiB
C
/*
|
|
* Copyright 2006 Freescale Semiconductor, Inc.
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* Version 2 as published by the Free Software Foundation.
|
|
*
|
|
* 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 <command.h>
|
|
#include <i2c.h> /* Functional interface */
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/fsl_i2c.h> /* HW definitions */
|
|
|
|
#define I2C_TIMEOUT (CONFIG_SYS_HZ / 4)
|
|
|
|
#define I2C_READ_BIT 1
|
|
#define I2C_WRITE_BIT 0
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
/* Initialize the bus pointer to whatever one the SPD EEPROM is on.
|
|
* Default is bus 0. This is necessary because the DDR initialization
|
|
* runs from ROM, and we can't switch buses because we can't modify
|
|
* the global variables.
|
|
*/
|
|
#ifndef CONFIG_SYS_SPD_BUS_NUM
|
|
#define CONFIG_SYS_SPD_BUS_NUM 0
|
|
#endif
|
|
static unsigned int i2c_bus_num __attribute__ ((section (".data"))) = CONFIG_SYS_SPD_BUS_NUM;
|
|
#if defined(CONFIG_I2C_MUX)
|
|
static unsigned int i2c_bus_num_mux __attribute__ ((section ("data"))) = 0;
|
|
#endif
|
|
|
|
static unsigned int i2c_bus_speed[2] = {CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SPEED};
|
|
|
|
static const struct fsl_i2c *i2c_dev[2] = {
|
|
(struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET),
|
|
#ifdef CONFIG_SYS_I2C2_OFFSET
|
|
(struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C2_OFFSET)
|
|
#endif
|
|
};
|
|
|
|
/* I2C speed map for a DFSR value of 1 */
|
|
|
|
/*
|
|
* Map I2C frequency dividers to FDR and DFSR values
|
|
*
|
|
* This structure is used to define the elements of a table that maps I2C
|
|
* frequency divider (I2C clock rate divided by I2C bus speed) to a value to be
|
|
* programmed into the Frequency Divider Ratio (FDR) and Digital Filter
|
|
* Sampling Rate (DFSR) registers.
|
|
*
|
|
* The actual table should be defined in the board file, and it must be called
|
|
* fsl_i2c_speed_map[].
|
|
*
|
|
* The last entry of the table must have a value of {-1, X}, where X is same
|
|
* FDR/DFSR values as the second-to-last entry. This guarantees that any
|
|
* search through the array will always find a match.
|
|
*
|
|
* The values of the divider must be in increasing numerical order, i.e.
|
|
* fsl_i2c_speed_map[x+1].divider > fsl_i2c_speed_map[x].divider.
|
|
*
|
|
* For this table, the values are based on a value of 1 for the DFSR
|
|
* register. See the application note AN2919 "Determining the I2C Frequency
|
|
* Divider Ratio for SCL"
|
|
*
|
|
* ColdFire I2C frequency dividers for FDR values are different from
|
|
* PowerPC. The protocol to use the I2C module is still the same.
|
|
* A different table is defined and are based on MCF5xxx user manual.
|
|
*
|
|
*/
|
|
static const struct {
|
|
unsigned short divider;
|
|
#ifdef __PPC__
|
|
u8 dfsr;
|
|
#endif
|
|
u8 fdr;
|
|
} fsl_i2c_speed_map[] = {
|
|
#ifdef __PPC__
|
|
{160, 1, 32}, {192, 1, 33}, {224, 1, 34}, {256, 1, 35},
|
|
{288, 1, 0}, {320, 1, 1}, {352, 6, 1}, {384, 1, 2}, {416, 6, 2},
|
|
{448, 1, 38}, {480, 1, 3}, {512, 1, 39}, {544, 11, 3}, {576, 1, 4},
|
|
{608, 22, 3}, {640, 1, 5}, {672, 32, 3}, {704, 11, 5}, {736, 43, 3},
|
|
{768, 1, 6}, {800, 54, 3}, {832, 11, 6}, {896, 1, 42}, {960, 1, 7},
|
|
{1024, 1, 43}, {1088, 22, 7}, {1152, 1, 8}, {1216, 43, 7}, {1280, 1, 9},
|
|
{1408, 22, 9}, {1536, 1, 10}, {1664, 22, 10}, {1792, 1, 46},
|
|
{1920, 1, 11}, {2048, 1, 47}, {2176, 43, 11}, {2304, 1, 12},
|
|
{2560, 1, 13}, {2816, 43, 13}, {3072, 1, 14}, {3328, 43, 14},
|
|
{3584, 1, 50}, {3840, 1, 15}, {4096, 1, 51}, {4608, 1, 16},
|
|
{5120, 1, 17}, {6144, 1, 18}, {7168, 1, 54}, {7680, 1, 19},
|
|
{8192, 1, 55}, {9216, 1, 20}, {10240, 1, 21}, {12288, 1, 22},
|
|
{14336, 1, 58}, {15360, 1, 23}, {16384, 1, 59}, {18432, 1, 24},
|
|
{20480, 1, 25}, {24576, 1, 26}, {28672, 1, 62}, {30720, 1, 27},
|
|
{32768, 1, 63}, {36864, 1, 28}, {40960, 1, 29}, {49152, 1, 30},
|
|
{61440, 1, 31}, {-1, 1, 31}
|
|
#elif defined(__M68K__)
|
|
{20, 32}, {22, 33}, {24, 34}, {26, 35},
|
|
{28, 0}, {28, 36}, {30, 1}, {32, 37},
|
|
{34, 2}, {36, 38}, {40, 3}, {40, 39},
|
|
{44, 4}, {48, 5}, {48, 40}, {56, 6},
|
|
{56, 41}, {64, 42}, {68, 7}, {72, 43},
|
|
{80, 8}, {80, 44}, {88, 9}, {96, 41},
|
|
{104, 10}, {112, 42}, {128, 11}, {128, 43},
|
|
{144, 12}, {160, 13}, {160, 48}, {192, 14},
|
|
{192, 49}, {224, 50}, {240, 15}, {256, 51},
|
|
{288, 16}, {320, 17}, {320, 52}, {384, 18},
|
|
{384, 53}, {448, 54}, {480, 19}, {512, 55},
|
|
{576, 20}, {640, 21}, {640, 56}, {768, 22},
|
|
{768, 57}, {960, 23}, {896, 58}, {1024, 59},
|
|
{1152, 24}, {1280, 25}, {1280, 60}, {1536, 26},
|
|
{1536, 61}, {1792, 62}, {1920, 27}, {2048, 63},
|
|
{2304, 28}, {2560, 29}, {3072, 30}, {3840, 31},
|
|
{-1, 31}
|
|
#endif
|
|
};
|
|
|
|
/**
|
|
* Set the I2C bus speed for a given I2C device
|
|
*
|
|
* @param dev: the I2C device
|
|
* @i2c_clk: I2C bus clock frequency
|
|
* @speed: the desired speed of the bus
|
|
*
|
|
* The I2C device must be stopped before calling this function.
|
|
*
|
|
* The return value is the actual bus speed that is set.
|
|
*/
|
|
static unsigned int set_i2c_bus_speed(const struct fsl_i2c *dev,
|
|
unsigned int i2c_clk, unsigned int speed)
|
|
{
|
|
unsigned short divider = min(i2c_clk / speed, (unsigned short) -1);
|
|
unsigned int i;
|
|
|
|
/*
|
|
* We want to choose an FDR/DFSR that generates an I2C bus speed that
|
|
* is equal to or lower than the requested speed. That means that we
|
|
* want the first divider that is equal to or greater than the
|
|
* calculated divider.
|
|
*/
|
|
|
|
for (i = 0; i < ARRAY_SIZE(fsl_i2c_speed_map); i++)
|
|
if (fsl_i2c_speed_map[i].divider >= divider) {
|
|
u8 fdr;
|
|
#ifdef __PPC__
|
|
u8 dfsr;
|
|
dfsr = fsl_i2c_speed_map[i].dfsr;
|
|
#endif
|
|
fdr = fsl_i2c_speed_map[i].fdr;
|
|
speed = i2c_clk / fsl_i2c_speed_map[i].divider;
|
|
writeb(fdr, &dev->fdr); /* set bus speed */
|
|
#ifdef __PPC__
|
|
writeb(dfsr, &dev->dfsrr); /* set default filter */
|
|
#endif
|
|
break;
|
|
}
|
|
|
|
return speed;
|
|
}
|
|
|
|
void
|
|
i2c_init(int speed, int slaveadd)
|
|
{
|
|
struct fsl_i2c *dev;
|
|
unsigned int temp;
|
|
|
|
dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET);
|
|
|
|
writeb(0, &dev->cr); /* stop I2C controller */
|
|
udelay(5); /* let it shutdown in peace */
|
|
temp = set_i2c_bus_speed(dev, gd->i2c1_clk, speed);
|
|
if (gd->flags & GD_FLG_RELOC)
|
|
i2c_bus_speed[0] = temp;
|
|
writeb(slaveadd << 1, &dev->adr); /* write slave address */
|
|
writeb(0x0, &dev->sr); /* clear status register */
|
|
writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
|
|
|
|
#ifdef CONFIG_SYS_I2C2_OFFSET
|
|
dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C2_OFFSET);
|
|
|
|
writeb(0, &dev->cr); /* stop I2C controller */
|
|
udelay(5); /* let it shutdown in peace */
|
|
temp = set_i2c_bus_speed(dev, gd->i2c2_clk, speed);
|
|
if (gd->flags & GD_FLG_RELOC)
|
|
i2c_bus_speed[1] = temp;
|
|
writeb(slaveadd << 1, &dev->adr); /* write slave address */
|
|
writeb(0x0, &dev->sr); /* clear status register */
|
|
writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
|
|
#endif
|
|
}
|
|
|
|
static __inline__ int
|
|
i2c_wait4bus(void)
|
|
{
|
|
unsigned long long timeval = get_ticks();
|
|
|
|
while (readb(&i2c_dev[i2c_bus_num]->sr) & I2C_SR_MBB) {
|
|
if ((get_ticks() - timeval) > usec2ticks(I2C_TIMEOUT))
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static __inline__ int
|
|
i2c_wait(int write)
|
|
{
|
|
u32 csr;
|
|
unsigned long long timeval = get_ticks();
|
|
|
|
do {
|
|
csr = readb(&i2c_dev[i2c_bus_num]->sr);
|
|
if (!(csr & I2C_SR_MIF))
|
|
continue;
|
|
|
|
writeb(0x0, &i2c_dev[i2c_bus_num]->sr);
|
|
|
|
if (csr & I2C_SR_MAL) {
|
|
debug("i2c_wait: MAL\n");
|
|
return -1;
|
|
}
|
|
|
|
if (!(csr & I2C_SR_MCF)) {
|
|
debug("i2c_wait: unfinished\n");
|
|
return -1;
|
|
}
|
|
|
|
if (write == I2C_WRITE_BIT && (csr & I2C_SR_RXAK)) {
|
|
debug("i2c_wait: No RXACK\n");
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
} while ((get_ticks() - timeval) < usec2ticks(I2C_TIMEOUT));
|
|
|
|
debug("i2c_wait: timed out\n");
|
|
return -1;
|
|
}
|
|
|
|
static __inline__ int
|
|
i2c_write_addr (u8 dev, u8 dir, int rsta)
|
|
{
|
|
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX
|
|
| (rsta ? I2C_CR_RSTA : 0),
|
|
&i2c_dev[i2c_bus_num]->cr);
|
|
|
|
writeb((dev << 1) | dir, &i2c_dev[i2c_bus_num]->dr);
|
|
|
|
if (i2c_wait(I2C_WRITE_BIT) < 0)
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
static __inline__ int
|
|
__i2c_write(u8 *data, int length)
|
|
{
|
|
int i;
|
|
|
|
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_MTX,
|
|
&i2c_dev[i2c_bus_num]->cr);
|
|
|
|
for (i = 0; i < length; i++) {
|
|
writeb(data[i], &i2c_dev[i2c_bus_num]->dr);
|
|
|
|
if (i2c_wait(I2C_WRITE_BIT) < 0)
|
|
break;
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
static __inline__ int
|
|
__i2c_read(u8 *data, int length)
|
|
{
|
|
int i;
|
|
|
|
writeb(I2C_CR_MEN | I2C_CR_MSTA | ((length == 1) ? I2C_CR_TXAK : 0),
|
|
&i2c_dev[i2c_bus_num]->cr);
|
|
|
|
/* dummy read */
|
|
readb(&i2c_dev[i2c_bus_num]->dr);
|
|
|
|
for (i = 0; i < length; i++) {
|
|
if (i2c_wait(I2C_READ_BIT) < 0)
|
|
break;
|
|
|
|
/* Generate ack on last next to last byte */
|
|
if (i == length - 2)
|
|
writeb(I2C_CR_MEN | I2C_CR_MSTA | I2C_CR_TXAK,
|
|
&i2c_dev[i2c_bus_num]->cr);
|
|
|
|
/* Generate stop on last byte */
|
|
if (i == length - 1)
|
|
writeb(I2C_CR_MEN | I2C_CR_TXAK, &i2c_dev[i2c_bus_num]->cr);
|
|
|
|
data[i] = readb(&i2c_dev[i2c_bus_num]->dr);
|
|
}
|
|
|
|
return i;
|
|
}
|
|
|
|
int
|
|
i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
|
|
{
|
|
int i = -1; /* signal error */
|
|
u8 *a = (u8*)&addr;
|
|
|
|
if (i2c_wait4bus() >= 0
|
|
&& i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0
|
|
&& __i2c_write(&a[4 - alen], alen) == alen)
|
|
i = 0; /* No error so far */
|
|
|
|
if (length
|
|
&& i2c_write_addr(dev, I2C_READ_BIT, 1) != 0)
|
|
i = __i2c_read(data, length);
|
|
|
|
writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr);
|
|
|
|
if (i == length)
|
|
return 0;
|
|
|
|
return -1;
|
|
}
|
|
|
|
int
|
|
i2c_write(u8 dev, uint addr, int alen, u8 *data, int length)
|
|
{
|
|
int i = -1; /* signal error */
|
|
u8 *a = (u8*)&addr;
|
|
|
|
if (i2c_wait4bus() >= 0
|
|
&& i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0
|
|
&& __i2c_write(&a[4 - alen], alen) == alen) {
|
|
i = __i2c_write(data, length);
|
|
}
|
|
|
|
writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr);
|
|
|
|
if (i == length)
|
|
return 0;
|
|
|
|
return -1;
|
|
}
|
|
|
|
int
|
|
i2c_probe(uchar chip)
|
|
{
|
|
/* For unknow reason the controller will ACK when
|
|
* probing for a slave with the same address, so skip
|
|
* it.
|
|
*/
|
|
if (chip == (readb(&i2c_dev[i2c_bus_num]->adr) >> 1))
|
|
return -1;
|
|
|
|
return i2c_read(chip, 0, 0, NULL, 0);
|
|
}
|
|
|
|
int i2c_set_bus_num(unsigned int bus)
|
|
{
|
|
#if defined(CONFIG_I2C_MUX)
|
|
if (bus < CONFIG_SYS_MAX_I2C_BUS) {
|
|
i2c_bus_num = bus;
|
|
} else {
|
|
int ret;
|
|
|
|
ret = i2x_mux_select_mux(bus);
|
|
if (ret)
|
|
return ret;
|
|
i2c_bus_num = 0;
|
|
}
|
|
i2c_bus_num_mux = bus;
|
|
#else
|
|
#ifdef CONFIG_SYS_I2C2_OFFSET
|
|
if (bus > 1) {
|
|
#else
|
|
if (bus > 0) {
|
|
#endif
|
|
return -1;
|
|
}
|
|
|
|
i2c_bus_num = bus;
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
int i2c_set_bus_speed(unsigned int speed)
|
|
{
|
|
unsigned int i2c_clk = (i2c_bus_num == 1) ? gd->i2c2_clk : gd->i2c1_clk;
|
|
|
|
writeb(0, &i2c_dev[i2c_bus_num]->cr); /* stop controller */
|
|
i2c_bus_speed[i2c_bus_num] =
|
|
set_i2c_bus_speed(i2c_dev[i2c_bus_num], i2c_clk, speed);
|
|
writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr); /* start controller */
|
|
|
|
return 0;
|
|
}
|
|
|
|
unsigned int i2c_get_bus_num(void)
|
|
{
|
|
#if defined(CONFIG_I2C_MUX)
|
|
return i2c_bus_num_mux;
|
|
#else
|
|
return i2c_bus_num;
|
|
#endif
|
|
}
|
|
|
|
unsigned int i2c_get_bus_speed(void)
|
|
{
|
|
return i2c_bus_speed[i2c_bus_num];
|
|
}
|
|
|
|
#endif /* CONFIG_HARD_I2C */
|