* - Status functions now read irqstatus_raw as per TRM guidelines
* (except for OMAP243X and OMAP34XX).
* - Driver now supports up to I2C5 (OMAP5).
+ *
+ * Copyright (c) 2014 Hannes Petermaier <oe5hpm@oevsv.at>, B&R
+ * - Added support for set_speed
+ *
*/
#include <common.h>
+#include <i2c.h>
#include <asm/arch/i2c.h>
#include <asm/io.h>
/* Absolutely safe for status update at 100 kHz I2C: */
#define I2C_WAIT 200
-static int wait_for_bb(void);
-static u16 wait_for_event(void);
-static void flush_fifo(void);
+static int wait_for_bb(struct i2c_adapter *adap);
+static struct i2c *omap24_get_base(struct i2c_adapter *adap);
+static u16 wait_for_event(struct i2c_adapter *adap);
+static void flush_fifo(struct i2c_adapter *adap);
+static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
+{
+ unsigned int sampleclk, prescaler;
+ int fsscll, fssclh;
-/*
- * For SPL boot some boards need i2c before SDRAM is initialised so force
- * variables to live in SRAM
- */
-static struct i2c __attribute__((section (".data"))) *i2c_base =
- (struct i2c *)I2C_DEFAULT_BASE;
-static unsigned int __attribute__((section (".data"))) bus_initialized[I2C_BUS_MAX] =
- { [0 ... (I2C_BUS_MAX-1)] = 0 };
-static unsigned int __attribute__((section (".data"))) current_bus = 0;
+ speed <<= 1;
+ prescaler = 0;
+ /*
+ * some divisors may cause a precission loss, but shouldn't
+ * be a big thing, because i2c_clk is then allready very slow.
+ */
+ while (prescaler <= 0xFF) {
+ sampleclk = I2C_IP_CLK / (prescaler+1);
-void i2c_init(int speed, int slaveadd)
-{
- int psc, fsscll, fssclh;
- int hsscll = 0, hssclh = 0;
- u32 scll, sclh;
- int timeout = I2C_TIMEOUT;
+ fsscll = sampleclk / speed;
+ fssclh = fsscll;
+ fsscll -= I2C_FASTSPEED_SCLL_TRIM;
+ fssclh -= I2C_FASTSPEED_SCLH_TRIM;
- /* Only handle standard, fast and high speeds */
- if ((speed != OMAP_I2C_STANDARD) &&
- (speed != OMAP_I2C_FAST_MODE) &&
- (speed != OMAP_I2C_HIGH_SPEED)) {
- printf("Error : I2C unsupported speed %d\n", speed);
- return;
- }
+ if (((fsscll > 0) && (fssclh > 0)) &&
+ ((fsscll <= (255-I2C_FASTSPEED_SCLL_TRIM)) &&
+ (fssclh <= (255-I2C_FASTSPEED_SCLH_TRIM)))) {
+ if (pscl)
+ *pscl = fsscll;
+ if (psch)
+ *psch = fssclh;
- psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
- psc -= 1;
- if (psc < I2C_PSC_MIN) {
- printf("Error : I2C unsupported prescalar %d\n", psc);
- return;
+ return prescaler;
+ }
+ prescaler++;
}
+ return -1;
+}
+static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ int psc, fsscll = 0, fssclh = 0;
+ int hsscll = 0, hssclh = 0;
+ u32 scll = 0, sclh = 0;
- if (speed == OMAP_I2C_HIGH_SPEED) {
+ if (speed >= OMAP_I2C_HIGH_SPEED) {
/* High speed */
+ psc = I2C_IP_CLK / I2C_INTERNAL_SAMPLING_CLK;
+ psc -= 1;
+ if (psc < I2C_PSC_MIN) {
+ printf("Error : I2C unsupported prescaler %d\n", psc);
+ return -1;
+ }
/* For first phase of HS mode */
- fsscll = fssclh = I2C_INTERNAL_SAMPLING_CLK /
- (2 * OMAP_I2C_FAST_MODE);
+ fsscll = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
+
+ fssclh = fsscll;
fsscll -= I2C_HIGHSPEED_PHASE_ONE_SCLL_TRIM;
fssclh -= I2C_HIGHSPEED_PHASE_ONE_SCLH_TRIM;
if (((fsscll < 0) || (fssclh < 0)) ||
((fsscll > 255) || (fssclh > 255))) {
puts("Error : I2C initializing first phase clock\n");
- return;
+ return -1;
}
/* For second phase of HS mode */
if (((fsscll < 0) || (fssclh < 0)) ||
((fsscll > 255) || (fssclh > 255))) {
puts("Error : I2C initializing second phase clock\n");
- return;
+ return -1;
}
scll = (unsigned int)hsscll << 8 | (unsigned int)fsscll;
} else {
/* Standard and fast speed */
- fsscll = fssclh = I2C_INTERNAL_SAMPLING_CLK / (2 * speed);
-
- fsscll -= I2C_FASTSPEED_SCLL_TRIM;
- fssclh -= I2C_FASTSPEED_SCLH_TRIM;
- if (((fsscll < 0) || (fssclh < 0)) ||
- ((fsscll > 255) || (fssclh > 255))) {
+ psc = omap24_i2c_findpsc(&scll, &sclh, speed);
+ if (0 > psc) {
puts("Error : I2C initializing clock\n");
- return;
+ return -1;
}
+ }
+
+ adap->speed = speed;
+ adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */
+ writew(0, &i2c_base->con);
+ writew(psc, &i2c_base->psc);
+ writew(scll, &i2c_base->scll);
+ writew(sclh, &i2c_base->sclh);
+ writew(I2C_CON_EN, &i2c_base->con);
+ writew(0xFFFF, &i2c_base->stat); /* clear all pending status */
+
+ return 0;
+}
- scll = (unsigned int)fsscll;
- sclh = (unsigned int)fssclh;
+static void omap24_i2c_deblock(struct i2c_adapter *adap)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ int i;
+ u16 systest;
+ u16 orgsystest;
+
+ /* set test mode ST_EN = 1 */
+ orgsystest = readw(&i2c_base->systest);
+ systest = orgsystest;
+ /* enable testmode */
+ systest |= I2C_SYSTEST_ST_EN;
+ writew(systest, &i2c_base->systest);
+ systest &= ~I2C_SYSTEST_TMODE_MASK;
+ systest |= 3 << I2C_SYSTEST_TMODE_SHIFT;
+ writew(systest, &i2c_base->systest);
+
+ /* set SCL, SDA = 1 */
+ systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
+ writew(systest, &i2c_base->systest);
+ udelay(10);
+
+ /* toggle scl 9 clocks */
+ for (i = 0; i < 9; i++) {
+ /* SCL = 0 */
+ systest &= ~I2C_SYSTEST_SCL_O;
+ writew(systest, &i2c_base->systest);
+ udelay(10);
+ /* SCL = 1 */
+ systest |= I2C_SYSTEST_SCL_O;
+ writew(systest, &i2c_base->systest);
+ udelay(10);
}
+ /* send stop */
+ systest &= ~I2C_SYSTEST_SDA_O;
+ writew(systest, &i2c_base->systest);
+ udelay(10);
+ systest |= I2C_SYSTEST_SCL_O | I2C_SYSTEST_SDA_O;
+ writew(systest, &i2c_base->systest);
+ udelay(10);
+
+ /* restore original mode */
+ writew(orgsystest, &i2c_base->systest);
+}
+
+static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ int timeout = I2C_TIMEOUT;
+ int deblock = 1;
+
+retry:
if (readw(&i2c_base->con) & I2C_CON_EN) {
writew(0, &i2c_base->con);
udelay(50000);
udelay(1000);
}
- writew(0, &i2c_base->con);
- writew(psc, &i2c_base->psc);
- writew(scll, &i2c_base->scll);
- writew(sclh, &i2c_base->sclh);
+ if (0 != omap24_i2c_setspeed(adap, speed)) {
+ printf("ERROR: failed to setup I2C bus-speed!\n");
+ return;
+ }
/* own address */
writew(slaveadd, &i2c_base->oa);
- writew(I2C_CON_EN, &i2c_base->con);
+
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
/*
* Have to enable interrupts for OMAP2/3, these IPs don't have
I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
#endif
udelay(1000);
- flush_fifo();
+ flush_fifo(adap);
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
- if (gd->flags & GD_FLG_RELOC)
- bus_initialized[current_bus] = 1;
+ /* Handle possible failed I2C state */
+ if (wait_for_bb(adap))
+ if (deblock == 1) {
+ omap24_i2c_deblock(adap);
+ deblock = 0;
+ goto retry;
+ }
}
-static void flush_fifo(void)
-{ u16 stat;
+static void flush_fifo(struct i2c_adapter *adap)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ u16 stat;
- /* note: if you try and read data when its not there or ready
+ /*
+ * note: if you try and read data when its not there or ready
* you get a bus error
*/
while (1) {
* i2c_probe: Use write access. Allows to identify addresses that are
* write-only (like the config register of dual-port EEPROMs)
*/
-int i2c_probe(uchar chip)
+static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
{
+ struct i2c *i2c_base = omap24_get_base(adap);
u16 status;
int res = 1; /* default = fail */
return res;
/* Wait until bus is free */
- if (wait_for_bb())
+ if (wait_for_bb(adap))
return res;
/* No data transfer, slave addr only */
- writew(0, &i2c_base->cnt);
- /* Set slave address */
writew(chip, &i2c_base->sa);
/* Stop bit needed here */
writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
I2C_CON_STP, &i2c_base->con);
- status = wait_for_event();
+ status = wait_for_event(adap);
if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
/*
*/
if (status == I2C_STAT_XRDY)
printf("i2c_probe: pads on bus %d probably not configured (status=0x%x)\n",
- current_bus, status);
+ adap->hwadapnr, status);
goto pr_exit;
}
/* Check for ACK (!NAK) */
if (!(status & I2C_STAT_NACK)) {
- res = 0; /* Device found */
- udelay(I2C_WAIT); /* Required by AM335X in SPL */
+ res = 0; /* Device found */
+ udelay(adap->waitdelay);/* Required by AM335X in SPL */
/* Abort transfer (force idle state) */
writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */
udelay(1000);
I2C_CON_STP, &i2c_base->con); /* STP */
}
pr_exit:
- flush_fifo();
+ flush_fifo(adap);
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
return res;
}
* or that do not need a register address at all (such as some clock
* distributors).
*/
-int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
+ int alen, uchar *buffer, int len)
{
+ struct i2c *i2c_base = omap24_get_base(adap);
int i2c_error = 0;
u16 status;
}
/* Wait until bus not busy */
- if (wait_for_bb())
+ if (wait_for_bb(adap))
return 1;
/* Zero, one or two bytes reg address (offset) */
#endif
/* Send register offset */
while (1) {
- status = wait_for_event();
+ status = wait_for_event(adap);
/* Try to identify bus that is not padconf'd for I2C */
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
printf("i2c_read (addr phase): pads on bus %d probably not configured (status=0x%x)\n",
- current_bus, status);
+ adap->hwadapnr, status);
goto rd_exit;
}
- if (status == 0 || status & I2C_STAT_NACK) {
+ if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
printf("i2c_read: error waiting for addr ACK (status=0x%x)\n",
status);
/* Receive data */
while (1) {
- status = wait_for_event();
+ status = wait_for_event(adap);
/*
* Try to identify bus that is not padconf'd for I2C. This
* state could be left over from previous transactions if
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
printf("i2c_read (data phase): pads on bus %d probably not configured (status=0x%x)\n",
- current_bus, status);
+ adap->hwadapnr, status);
goto rd_exit;
}
- if (status == 0 || status & I2C_STAT_NACK) {
+ if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
goto rd_exit;
}
}
rd_exit:
- flush_fifo();
+ flush_fifo(adap);
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
return i2c_error;
}
/* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
-int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
+ int alen, uchar *buffer, int len)
{
+ struct i2c *i2c_base = omap24_get_base(adap);
int i;
u16 status;
int i2c_error = 0;
+ int timeout = I2C_TIMEOUT;
if (alen < 0) {
puts("I2C write: addr len < 0\n");
}
/* Wait until bus not busy */
- if (wait_for_bb())
+ if (wait_for_bb(adap))
return 1;
/* Start address phase - will write regoffset + len bytes data */
while (alen) {
/* Must write reg offset (one or two bytes) */
- status = wait_for_event();
+ status = wait_for_event(adap);
/* Try to identify bus that is not padconf'd for I2C */
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
printf("i2c_write: pads on bus %d probably not configured (status=0x%x)\n",
- current_bus, status);
+ adap->hwadapnr, status);
goto wr_exit;
}
- if (status == 0 || status & I2C_STAT_NACK) {
+ if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
printf("i2c_write: error waiting for addr ACK (status=0x%x)\n",
status);
}
/* Address phase is over, now write data */
for (i = 0; i < len; i++) {
- status = wait_for_event();
- if (status == 0 || status & I2C_STAT_NACK) {
+ status = wait_for_event(adap);
+ if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
printf("i2c_write: error waiting for data ACK (status=0x%x)\n",
status);
goto wr_exit;
}
}
+ /*
+ * poll ARDY bit for making sure that last byte really has been
+ * transferred on the bus.
+ */
+ do {
+ status = wait_for_event(adap);
+ } while (!(status & I2C_STAT_ARDY) && timeout--);
+ if (timeout <= 0)
+ printf("i2c_write: timed out writig last byte!\n");
wr_exit:
- flush_fifo();
+ flush_fifo(adap);
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
return i2c_error;
}
* Wait for the bus to be free by checking the Bus Busy (BB)
* bit to become clear
*/
-static int wait_for_bb(void)
+static int wait_for_bb(struct i2c_adapter *adap)
{
+ struct i2c *i2c_base = omap24_get_base(adap);
int timeout = I2C_TIMEOUT;
u16 stat;
I2C_STAT_BB) && timeout--) {
#endif
writew(stat, &i2c_base->stat);
- udelay(I2C_WAIT);
+ udelay(adap->waitdelay);
}
if (timeout <= 0) {
* Wait for the I2C controller to complete current action
* and update status
*/
-static u16 wait_for_event(void)
+static u16 wait_for_event(struct i2c_adapter *adap)
{
+ struct i2c *i2c_base = omap24_get_base(adap);
u16 status;
int timeout = I2C_TIMEOUT;
do {
- udelay(I2C_WAIT);
+ udelay(adap->waitdelay);
#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
status = readw(&i2c_base->stat);
#else
* not been configured for I2C, and/or pull-ups are missing.
*/
printf("Check if pads/pull-ups of bus %d are properly configured\n",
- current_bus);
+ adap->hwadapnr);
writew(0xFFFF, &i2c_base->stat);
status = 0;
}
return status;
}
-int i2c_set_bus_num(unsigned int bus)
+static struct i2c *omap24_get_base(struct i2c_adapter *adap)
{
- if (bus >= I2C_BUS_MAX) {
- printf("Bad bus: %x\n", bus);
- return -1;
- }
-
- switch (bus) {
- default:
- bus = 0; /* Fall through */
+ switch (adap->hwadapnr) {
case 0:
- i2c_base = (struct i2c *)I2C_BASE1;
+ return (struct i2c *)I2C_BASE1;
break;
case 1:
- i2c_base = (struct i2c *)I2C_BASE2;
+ return (struct i2c *)I2C_BASE2;
break;
#if (I2C_BUS_MAX > 2)
case 2:
- i2c_base = (struct i2c *)I2C_BASE3;
+ return (struct i2c *)I2C_BASE3;
break;
#if (I2C_BUS_MAX > 3)
case 3:
- i2c_base = (struct i2c *)I2C_BASE4;
+ return (struct i2c *)I2C_BASE4;
break;
#if (I2C_BUS_MAX > 4)
case 4:
- i2c_base = (struct i2c *)I2C_BASE5;
+ return (struct i2c *)I2C_BASE5;
break;
#endif
#endif
#endif
+ default:
+ printf("wrong hwadapnr: %d\n", adap->hwadapnr);
+ break;
}
+ return NULL;
+}
- current_bus = bus;
+#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
+#define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
+#endif
+#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1)
+#define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE
+#endif
- if (!bus_initialized[current_bus])
- i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+U_BOOT_I2C_ADAP_COMPLETE(omap24_0, omap24_i2c_init, omap24_i2c_probe,
+ omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
+ CONFIG_SYS_OMAP24_I2C_SPEED,
+ CONFIG_SYS_OMAP24_I2C_SLAVE,
+ 0)
+U_BOOT_I2C_ADAP_COMPLETE(omap24_1, omap24_i2c_init, omap24_i2c_probe,
+ omap24_i2c_read, omap24_i2c_write, omap24_i2c_setspeed,
+ CONFIG_SYS_OMAP24_I2C_SPEED1,
+ CONFIG_SYS_OMAP24_I2C_SLAVE1,
+ 1)
+#if (I2C_BUS_MAX > 2)
+#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED2)
+#define CONFIG_SYS_OMAP24_I2C_SPEED2 CONFIG_SYS_OMAP24_I2C_SPEED
+#endif
+#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE2)
+#define CONFIG_SYS_OMAP24_I2C_SLAVE2 CONFIG_SYS_OMAP24_I2C_SLAVE
+#endif
- return 0;
-}
+U_BOOT_I2C_ADAP_COMPLETE(omap24_2, omap24_i2c_init, omap24_i2c_probe,
+ omap24_i2c_read, omap24_i2c_write, NULL,
+ CONFIG_SYS_OMAP24_I2C_SPEED2,
+ CONFIG_SYS_OMAP24_I2C_SLAVE2,
+ 2)
+#if (I2C_BUS_MAX > 3)
+#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED3)
+#define CONFIG_SYS_OMAP24_I2C_SPEED3 CONFIG_SYS_OMAP24_I2C_SPEED
+#endif
+#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE3)
+#define CONFIG_SYS_OMAP24_I2C_SLAVE3 CONFIG_SYS_OMAP24_I2C_SLAVE
+#endif
-int i2c_get_bus_num(void)
-{
- return (int) current_bus;
-}
+U_BOOT_I2C_ADAP_COMPLETE(omap24_3, omap24_i2c_init, omap24_i2c_probe,
+ omap24_i2c_read, omap24_i2c_write, NULL,
+ CONFIG_SYS_OMAP24_I2C_SPEED3,
+ CONFIG_SYS_OMAP24_I2C_SLAVE3,
+ 3)
+#if (I2C_BUS_MAX > 4)
+#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED4)
+#define CONFIG_SYS_OMAP24_I2C_SPEED4 CONFIG_SYS_OMAP24_I2C_SPEED
+#endif
+#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE4)
+#define CONFIG_SYS_OMAP24_I2C_SLAVE4 CONFIG_SYS_OMAP24_I2C_SLAVE
+#endif
+
+U_BOOT_I2C_ADAP_COMPLETE(omap24_4, omap24_i2c_init, omap24_i2c_probe,
+ omap24_i2c_read, omap24_i2c_write, NULL,
+ CONFIG_SYS_OMAP24_I2C_SPEED4,
+ CONFIG_SYS_OMAP24_I2C_SLAVE4,
+ 4)
+#endif
+#endif
+#endif
projects / u-boot / blobdiff