#include <asm/errno.h>
#include <asm/io.h>
#include <i2c.h>
+#include <watchdog.h>
struct mxc_i2c_regs {
uint32_t iadr;
#define I2SR_ICF (1 << 7)
#define I2SR_IBB (1 << 5)
+#define I2SR_IAL (1 << 4)
#define I2SR_IIF (1 << 1)
#define I2SR_RX_NO_AK (1 << 0)
-#ifdef CONFIG_SYS_I2C_BASE
-#define I2C_BASE CONFIG_SYS_I2C_BASE
-#else
+#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_SYS_I2C_BASE)
#error "define CONFIG_SYS_I2C_BASE to use the mxc_i2c driver"
#endif
-#define I2C_MAX_TIMEOUT 10000
-
static u16 i2c_clk_div[50][2] = {
{ 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
{ 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
#endif
/* Divider value calculation */
- i2c_clk_rate = mxc_get_clock(MXC_IPG_PERCLK);
+ i2c_clk_rate = mxc_get_clock(MXC_I2C_CLK);
div = (i2c_clk_rate + rate - 1) / rate;
if (div < i2c_clk_div[0][0])
clk_div = 0;
}
/*
- * Reset I2C Controller
- */
-void i2c_reset(void)
-{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
-
- writeb(0, &i2c_regs->i2cr); /* Reset module */
- writeb(0, &i2c_regs->i2sr);
-}
-
-/*
- * Init I2C Bus
+ * Set I2C Bus speed
*/
-void i2c_init(int speed, int unused)
+static int bus_i2c_set_bus_speed(void *base, int speed)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
+ struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
u8 clk_idx = i2c_imx_get_clk(speed);
u8 idx = i2c_clk_div[clk_idx][1];
/* Store divider value */
writeb(idx, &i2c_regs->ifdr);
- i2c_reset();
-}
-
-/*
- * Set I2C Speed
- */
-int i2c_set_bus_speed(unsigned int speed)
-{
- i2c_init(speed, 0);
+ /* Reset module */
+ writeb(0, &i2c_regs->i2cr);
+ writeb(0, &i2c_regs->i2sr);
return 0;
}
/*
* Get I2C Speed
*/
-unsigned int i2c_get_bus_speed(void)
+static unsigned int bus_i2c_get_bus_speed(void *base)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
+ struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
u8 clk_idx = readb(&i2c_regs->ifdr);
u8 clk_div;
for (clk_div = 0; i2c_clk_div[clk_div][1] != clk_idx; clk_div++)
;
- return mxc_get_clock(MXC_IPG_PERCLK) / i2c_clk_div[clk_div][0];
+ return mxc_get_clock(MXC_I2C_CLK) / i2c_clk_div[clk_div][0];
}
-/*
- * Wait for bus to be busy (or free if for_busy = 0)
- *
- * for_busy = 1: Wait for IBB to be asserted
- * for_busy = 0: Wait for IBB to be de-asserted
- */
-int i2c_imx_bus_busy(int for_busy)
-{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
- unsigned int temp;
-
- int timeout = I2C_MAX_TIMEOUT;
-
- while (timeout--) {
- temp = readb(&i2c_regs->i2sr);
-
- if (for_busy && (temp & I2SR_IBB))
- return 0;
- if (!for_busy && !(temp & I2SR_IBB))
- return 0;
-
- udelay(1);
- }
-
- return 1;
-}
+#define ST_BUS_IDLE (0 | (I2SR_IBB << 8))
+#define ST_BUS_BUSY (I2SR_IBB | (I2SR_IBB << 8))
+#define ST_IIF (I2SR_IIF | (I2SR_IIF << 8))
-/*
- * Wait for transaction to complete
- */
-int i2c_imx_trx_complete(void)
+static int wait_for_sr_state(struct mxc_i2c_regs *i2c_regs, unsigned state)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
- int timeout = I2C_MAX_TIMEOUT;
-
- while (timeout--) {
- if (readb(&i2c_regs->i2sr) & I2SR_IIF)
- return 0;
-
- udelay(1);
+ unsigned sr;
+ ulong elapsed;
+ ulong start_time = get_timer(0);
+ for (;;) {
+ sr = readb(&i2c_regs->i2sr);
+ if (sr & I2SR_IAL) {
+ writeb(sr & ~I2SR_IAL, &i2c_regs->i2sr);
+ printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
+ __func__, sr, readb(&i2c_regs->i2cr), state);
+ return -ERESTART;
+ }
+ if ((sr & (state >> 8)) == (unsigned char)state)
+ return sr;
+ WATCHDOG_RESET();
+ elapsed = get_timer(start_time);
+ if (elapsed > (CONFIG_SYS_HZ / 10)) /* .1 seconds */
+ break;
}
-
+ printf("%s: failed sr=%x cr=%x state=%x\n", __func__,
+ sr, readb(&i2c_regs->i2cr), state);
return -ETIMEDOUT;
}
writeb(0, &i2c_regs->i2sr);
writeb(byte, &i2c_regs->i2dr);
- ret = i2c_imx_trx_complete();
+ ret = wait_for_sr_state(i2c_regs, ST_IIF);
if (ret < 0)
return ret;
- ret = readb(&i2c_regs->i2sr);
if (ret & I2SR_RX_NO_AK)
return -ENODEV;
return 0;
}
/*
- * Start the controller
+ * Stop I2C transaction
*/
-int i2c_imx_start(void)
+static void i2c_imx_stop(struct mxc_i2c_regs *i2c_regs)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
- unsigned int temp = 0;
- int result;
-
- /* Enable I2C controller */
- writeb(0, &i2c_regs->i2sr);
- writeb(I2CR_IEN, &i2c_regs->i2cr);
-
- /* Wait controller to be stable */
- udelay(50);
-
- /* Start I2C transaction */
- temp = readb(&i2c_regs->i2cr);
- temp |= I2CR_MSTA;
- writeb(temp, &i2c_regs->i2cr);
-
- result = i2c_imx_bus_busy(1);
- if (result)
- return result;
+ int ret;
+ unsigned int temp = readb(&i2c_regs->i2cr);
- temp |= I2CR_MTX | I2CR_TX_NO_AK;
+ temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, &i2c_regs->i2cr);
-
- return 0;
+ ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
+ if (ret < 0)
+ printf("%s:trigger stop failed\n", __func__);
}
/*
- * Stop the controller
+ * Send start signal, chip address and
+ * write register address
*/
-void i2c_imx_stop(void)
+static int i2c_init_transfer_(struct mxc_i2c_regs *i2c_regs,
+ uchar chip, uint addr, int alen)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
- unsigned int temp = 0;
+ unsigned int temp;
+ int ret;
+
+ /* Enable I2C controller */
+ if (!(readb(&i2c_regs->i2cr) & I2CR_IEN)) {
+ writeb(I2CR_IEN, &i2c_regs->i2cr);
+ /* Wait for controller to be stable */
+ udelay(50);
+ }
+ if (readb(&i2c_regs->iadr) == (chip << 1))
+ writeb((chip << 1) ^ 2, &i2c_regs->iadr);
+ writeb(0, &i2c_regs->i2sr);
+ ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
+ if (ret < 0)
+ return ret;
- /* Stop I2C transaction */
+ /* Start I2C transaction */
temp = readb(&i2c_regs->i2cr);
- temp &= ~(I2CR_MSTA | I2CR_MTX);
+ temp |= I2CR_MSTA;
writeb(temp, &i2c_regs->i2cr);
- i2c_imx_bus_busy(0);
-
- /* Disable I2C controller */
- writeb(0, &i2c_regs->i2cr);
-}
+ ret = wait_for_sr_state(i2c_regs, ST_BUS_BUSY);
+ if (ret < 0)
+ return ret;
-/*
- * Send start signal, chip address and
- * write register address
- */
-static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
- uchar chip, uint addr, int alen)
-{
- int ret = i2c_imx_start();
- if (ret)
- goto exit;
+ temp |= I2CR_MTX | I2CR_TX_NO_AK;
+ writeb(temp, &i2c_regs->i2cr);
/* write slave address */
ret = tx_byte(i2c_regs, chip << 1);
if (ret < 0)
- goto exit;
+ return ret;
while (alen--) {
ret = tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
if (ret < 0)
- goto exit;
+ return ret;
}
return 0;
-exit:
- i2c_imx_stop();
- return ret;
}
-/*
- * Try if a chip add given address responds (probe the chip)
- */
-int i2c_probe(uchar chip)
+static int i2c_idle_bus(void *base);
+
+static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
+ uchar chip, uint addr, int alen)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
+ int retry;
int ret;
+ for (retry = 0; retry < 3; retry++) {
+ ret = i2c_init_transfer_(i2c_regs, chip, addr, alen);
+ if (ret >= 0)
+ return 0;
+ i2c_imx_stop(i2c_regs);
+ if (ret == -ENODEV)
+ return ret;
- ret = i2c_imx_start();
- if (ret)
- return ret;
-
- ret = tx_byte(i2c_regs, chip << 1);
- i2c_imx_stop();
+ printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
+ retry);
+ if (ret != -ERESTART)
+ writeb(0, &i2c_regs->i2cr); /* Disable controller */
+ udelay(100);
+ if (i2c_idle_bus(i2c_regs) < 0)
+ break;
+ }
+ printf("%s: give up i2c_regs=%p\n", __func__, i2c_regs);
return ret;
}
/*
* Read data from I2C device
*/
-int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
+int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
+ int len)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
int ret;
unsigned int temp;
int i;
+ struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
if (ret < 0)
ret = tx_byte(i2c_regs, (chip << 1) | 1);
if (ret < 0) {
- i2c_imx_stop();
+ i2c_imx_stop(i2c_regs);
return ret;
}
/* read data */
for (i = 0; i < len; i++) {
- ret = i2c_imx_trx_complete();
- if (ret) {
- i2c_imx_stop();
+ ret = wait_for_sr_state(i2c_regs, ST_IIF);
+ if (ret < 0) {
+ i2c_imx_stop(i2c_regs);
return ret;
}
* controller from generating another clock cycle
*/
if (i == (len - 1)) {
- temp = readb(&i2c_regs->i2cr);
- temp &= ~(I2CR_MSTA | I2CR_MTX);
- writeb(temp, &i2c_regs->i2cr);
- i2c_imx_bus_busy(0);
+ i2c_imx_stop(i2c_regs);
} else if (i == (len - 2)) {
temp = readb(&i2c_regs->i2cr);
temp |= I2CR_TX_NO_AK;
writeb(temp, &i2c_regs->i2cr);
}
-
writeb(0, &i2c_regs->i2sr);
buf[i] = readb(&i2c_regs->i2dr);
}
-
- i2c_imx_stop();
-
- return ret;
+ i2c_imx_stop(i2c_regs);
+ return 0;
}
/*
* Write data to I2C device
*/
-int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
+int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
+ const uchar *buf, int len)
{
- struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
int ret;
int i;
+ struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
if (ret < 0)
if (ret < 0)
break;
}
+ i2c_imx_stop(i2c_regs);
+ return ret;
+}
- i2c_imx_stop();
+struct i2c_parms {
+ void *base;
+ void *idle_bus_data;
+ int (*idle_bus_fn)(void *p);
+};
- return ret;
+struct sram_data {
+ unsigned curr_i2c_bus;
+ struct i2c_parms i2c_data[3];
+};
+
+/*
+ * For SPL boot some boards need i2c before SDRAM is initialized so force
+ * variables to live in SRAM
+ */
+static struct sram_data __attribute__((section(".data"))) srdata;
+
+void *get_base(void)
+{
+#ifdef CONFIG_SYS_I2C_BASE
+#ifdef CONFIG_I2C_MULTI_BUS
+ void *ret = srdata.i2c_data[srdata.curr_i2c_bus].base;
+ if (ret)
+ return ret;
+#endif
+ return (void *)CONFIG_SYS_I2C_BASE;
+#elif defined(CONFIG_I2C_MULTI_BUS)
+ return srdata.i2c_data[srdata.curr_i2c_bus].base;
+#else
+ return srdata.i2c_data[0].base;
+#endif
+}
+
+static struct i2c_parms *i2c_get_parms(void *base)
+{
+ int i = 0;
+ struct i2c_parms *p = srdata.i2c_data;
+ while (i < ARRAY_SIZE(srdata.i2c_data)) {
+ if (p->base == base)
+ return p;
+ p++;
+ i++;
+ }
+ printf("Invalid I2C base: %p\n", base);
+ return NULL;
+}
+
+static int i2c_idle_bus(void *base)
+{
+ struct i2c_parms *p = i2c_get_parms(base);
+ if (p && p->idle_bus_fn)
+ return p->idle_bus_fn(p->idle_bus_data);
+ return 0;
+}
+
+#ifdef CONFIG_I2C_MULTI_BUS
+unsigned int i2c_get_bus_num(void)
+{
+ return srdata.curr_i2c_bus;
+}
+
+int i2c_set_bus_num(unsigned bus_idx)
+{
+ if (bus_idx >= ARRAY_SIZE(srdata.i2c_data))
+ return -1;
+ if (!srdata.i2c_data[bus_idx].base)
+ return -1;
+ srdata.curr_i2c_bus = bus_idx;
+ return 0;
+}
+#endif
+
+int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
+{
+ return bus_i2c_read(get_base(), chip, addr, alen, buf, len);
+}
+
+int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
+{
+ return bus_i2c_write(get_base(), chip, addr, alen, buf, len);
+}
+
+/*
+ * Test if a chip at a given address responds (probe the chip)
+ */
+int i2c_probe(uchar chip)
+{
+ return bus_i2c_write(get_base(), chip, 0, 0, NULL, 0);
+}
+
+void bus_i2c_init(void *base, int speed, int unused,
+ int (*idle_bus_fn)(void *p), void *idle_bus_data)
+{
+ int i = 0;
+ struct i2c_parms *p = srdata.i2c_data;
+ if (!base)
+ return;
+ for (;;) {
+ if (!p->base || (p->base == base)) {
+ p->base = base;
+ if (idle_bus_fn) {
+ p->idle_bus_fn = idle_bus_fn;
+ p->idle_bus_data = idle_bus_data;
+ }
+ break;
+ }
+ p++;
+ i++;
+ if (i >= ARRAY_SIZE(srdata.i2c_data))
+ return;
+ }
+ bus_i2c_set_bus_speed(base, speed);
+}
+
+/*
+ * Init I2C Bus
+ */
+void i2c_init(int speed, int unused)
+{
+ bus_i2c_init(get_base(), speed, unused, NULL, NULL);
+}
+
+/*
+ * Set I2C Speed
+ */
+int i2c_set_bus_speed(unsigned int speed)
+{
+ return bus_i2c_set_bus_speed(get_base(), speed);
+}
+
+/*
+ * Get I2C Speed
+ */
+unsigned int i2c_get_bus_speed(void)
+{
+ return bus_i2c_get_bus_speed(get_base());
}
projects / platform / kernel / u-boot.git / blobdiff