*
* Adapted for OMAP2420 I2C, r-woodruff2@ti.com
*
+ * Copyright (c) 2013 Lubomir Popov <lpopov@mm-sol.com>, MM Solutions
+ * New i2c_read, i2c_write and i2c_probe functions, tested on OMAP4
+ * (4430/60/70), OMAP5 (5430) and AM335X (3359); should work on older
+ * OMAPs and derivatives as well. The only anticipated exception would
+ * be the OMAP2420, which shall require driver modification.
+ * - Rewritten i2c_read to operate correctly with all types of chips
+ * (old function could not read consistent data from some I2C slaves).
+ * - Optimized i2c_write.
+ * - New i2c_probe, performs write access vs read. The old probe could
+ * hang the system under certain conditions (e.g. unconfigured pads).
+ * - The read/write/probe functions try to identify unconfigured bus.
+ * - 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 Schmelzer <oe5hpm@oevsv.at>, B&R
+ * - Added support for set_speed
+ *
*/
#include <common.h>
+#include <dm.h>
+#include <i2c.h>
#include <asm/arch/i2c.h>
#include <asm/io.h>
#include "omap24xx_i2c.h"
-DECLARE_GLOBAL_DATA_PTR;
-
#define I2C_TIMEOUT 1000
-static int wait_for_bb(void);
-static u16 wait_for_pin(void);
-static void flush_fifo(void);
+/* Absolutely safe for status update at 100 kHz I2C: */
+#define I2C_WAIT 200
+
+struct omap_i2c {
+ struct udevice *clk;
+ struct i2c *regs;
+ unsigned int speed;
+ int waitdelay;
+ int clk_id;
+};
+
+static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
+{
+ unsigned long internal_clk = 0, fclk;
+ unsigned int prescaler;
+
+ /*
+ * This method is only called for Standard and Fast Mode speeds
+ *
+ * For some TI SoCs it is explicitly written in TRM (e,g, SPRUHZ6G,
+ * page 5685, Table 24-7)
+ * that the internal I2C clock (after prescaler) should be between
+ * 7-12 MHz (at least for Fast Mode (FS)).
+ *
+ * Such approach is used in v4.9 Linux kernel in:
+ * ./drivers/i2c/busses/i2c-omap.c (omap_i2c_init function).
+ */
+
+ speed /= 1000; /* convert speed to kHz */
+
+ if (speed > 100)
+ internal_clk = 9600;
+ else
+ internal_clk = 4000;
+
+ fclk = I2C_IP_CLK / 1000;
+ prescaler = fclk / internal_clk;
+ prescaler = prescaler - 1;
+
+ if (speed > 100) {
+ unsigned long scl;
+
+ /* Fast mode */
+ scl = internal_clk / speed;
+ *pscl = scl - (scl / 3) - I2C_FASTSPEED_SCLL_TRIM;
+ *psch = (scl / 3) - I2C_FASTSPEED_SCLH_TRIM;
+ } else {
+ /* Standard mode */
+ *pscl = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLL_TRIM;
+ *psch = internal_clk / (speed * 2) - I2C_FASTSPEED_SCLH_TRIM;
+ }
+
+ debug("%s: speed [kHz]: %d psc: 0x%x sscl: 0x%x ssch: 0x%x\n",
+ __func__, speed, prescaler, *pscl, *psch);
+
+ if (*pscl <= 0 || *psch <= 0 || prescaler <= 0)
+ return -EINVAL;
+
+ return prescaler;
+}
/*
- * For SPL boot some boards need i2c before SDRAM is initialised so force
- * variables to live in SRAM
+ * Wait for the bus to be free by checking the Bus Busy (BB)
+ * bit to become clear
*/
-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;
+static int wait_for_bb(struct i2c *i2c_base, int waitdelay)
+{
+ int timeout = I2C_TIMEOUT;
+ u16 stat;
-void i2c_init(int speed, int slaveadd)
+ writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/
+#if defined(CONFIG_OMAP34XX)
+ while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
+#else
+ /* Read RAW status */
+ while ((stat = readw(&i2c_base->irqstatus_raw) &
+ I2C_STAT_BB) && timeout--) {
+#endif
+ writew(stat, &i2c_base->stat);
+ udelay(waitdelay);
+ }
+
+ if (timeout <= 0) {
+ printf("Timed out in wait_for_bb: status=%04x\n",
+ stat);
+ return 1;
+ }
+ writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
+ return 0;
+}
+
+/*
+ * Wait for the I2C controller to complete current action
+ * and update status
+ */
+static u16 wait_for_event(struct i2c *i2c_base, int waitdelay)
{
- int psc, fsscll, fssclh;
- int hsscll = 0, hssclh = 0;
- u32 scll, sclh;
+ u16 status;
int timeout = I2C_TIMEOUT;
- /* 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;
+ do {
+ udelay(waitdelay);
+#if defined(CONFIG_OMAP34XX)
+ status = readw(&i2c_base->stat);
+#else
+ /* Read RAW status */
+ status = readw(&i2c_base->irqstatus_raw);
+#endif
+ } while (!(status &
+ (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
+ I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
+ I2C_STAT_AL)) && timeout--);
+
+ if (timeout <= 0) {
+ printf("Timed out in wait_for_event: status=%04x\n",
+ status);
+ /*
+ * If status is still 0 here, probably the bus pads have
+ * not been configured for I2C, and/or pull-ups are missing.
+ */
+ printf("Check if pads/pull-ups of bus are properly configured\n");
+ writew(0xFFFF, &i2c_base->stat);
+ status = 0;
}
- 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 status;
+}
+
+static void flush_fifo(struct i2c *i2c_base)
+{
+ u16 stat;
+
+ /*
+ * note: if you try and read data when its not there or ready
+ * you get a bus error
+ */
+ while (1) {
+ stat = readw(&i2c_base->stat);
+ if (stat == I2C_STAT_RRDY) {
+ readb(&i2c_base->data);
+ writew(I2C_STAT_RRDY, &i2c_base->stat);
+ udelay(1000);
+ } else
+ break;
}
+}
- if (speed == OMAP_I2C_HIGH_SPEED) {
+static int __omap24_i2c_setspeed(struct i2c *i2c_base, uint speed,
+ int *waitdelay)
+{
+ int psc, fsscll = 0, fssclh = 0;
+ int hsscll = 0, hssclh = 0;
+ u32 scll = 0, sclh = 0;
+
+ 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;
}
+ }
+
+ *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 */
- scll = (unsigned int)fsscll;
- sclh = (unsigned int)fssclh;
+ return 0;
+}
+
+static void omap24_i2c_deblock(struct i2c *i2c_base)
+{
+ 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 *i2c_base, int speed, int slaveadd,
+ int *waitdelay)
+{
+ 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(i2c_base, speed, waitdelay)) {
+ printf("ERROR: failed to setup I2C bus-speed!\n");
+ return;
+ }
/* own address */
writew(slaveadd, &i2c_base->oa);
- writew(I2C_CON_EN, &i2c_base->con);
- /* have to enable intrrupts or OMAP i2c module doesn't work */
+#if defined(CONFIG_OMAP34XX)
+ /*
+ * Have to enable interrupts for OMAP2/3, these IPs don't have
+ * an 'irqstatus_raw' register and we shall have to poll 'stat'
+ */
writew(I2C_IE_XRDY_IE | I2C_IE_RRDY_IE | I2C_IE_ARDY_IE |
- I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
+ I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
+#endif
udelay(1000);
- flush_fifo();
+ flush_fifo(i2c_base);
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(i2c_base, *waitdelay))
+ if (deblock == 1) {
+ omap24_i2c_deblock(i2c_base);
+ deblock = 0;
+ goto retry;
+ }
}
-static int i2c_read_byte(u8 devaddr, u16 regoffset, u8 alen, u8 *value)
+/*
+ * i2c_probe: Use write access. Allows to identify addresses that are
+ * write-only (like the config register of dual-port EEPROMs)
+ */
+static int __omap24_i2c_probe(struct i2c *i2c_base, int waitdelay, uchar chip)
{
- int i2c_error = 0;
u16 status;
- int i = 2 - alen;
- u8 tmpbuf[2] = {(regoffset) >> 8, regoffset & 0xff};
- u16 w;
+ int res = 1; /* default = fail */
- /* wait until bus not busy */
- if (wait_for_bb())
- return 1;
+ if (chip == readw(&i2c_base->oa))
+ return res;
- /* one byte only */
- writew(alen, &i2c_base->cnt);
- /* set slave address */
- writew(devaddr, &i2c_base->sa);
- /* no stop bit needed here */
- writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
- I2C_CON_TRX, &i2c_base->con);
+ /* Wait until bus is free */
+ if (wait_for_bb(i2c_base, waitdelay))
+ return res;
- /* send register offset */
- while (1) {
- status = wait_for_pin();
- if (status == 0 || status & I2C_STAT_NACK) {
- i2c_error = 1;
- goto read_exit;
- }
- if (status & I2C_STAT_XRDY) {
- w = tmpbuf[i++];
-#if !(defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
- defined(CONFIG_OMAP54XX))
- w |= tmpbuf[i++] << 8;
-#endif
- writew(w, &i2c_base->data);
- writew(I2C_STAT_XRDY, &i2c_base->stat);
- }
- if (status & I2C_STAT_ARDY) {
- writew(I2C_STAT_ARDY, &i2c_base->stat);
- break;
- }
+ /* No data transfer, slave addr only */
+ 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(i2c_base, waitdelay);
+
+ if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
+ /*
+ * With current high-level command implementation, notifying
+ * the user shall flood the console with 127 messages. If
+ * silent exit is desired upon unconfigured bus, remove the
+ * following 'if' section:
+ */
+ if (status == I2C_STAT_XRDY)
+ printf("i2c_probe: pads on bus probably not configured (status=0x%x)\n",
+ status);
+
+ goto pr_exit;
}
- /* set slave address */
- writew(devaddr, &i2c_base->sa);
- /* read one byte from slave */
- writew(1, &i2c_base->cnt);
- /* need stop bit here */
- writew(I2C_CON_EN | I2C_CON_MST |
- I2C_CON_STT | I2C_CON_STP,
- &i2c_base->con);
-
- /* receive data */
- while (1) {
- status = wait_for_pin();
- if (status == 0 || status & I2C_STAT_NACK) {
- i2c_error = 1;
- goto read_exit;
- }
- if (status & I2C_STAT_RRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
- defined(CONFIG_OMAP54XX)
- *value = readb(&i2c_base->data);
-#else
- *value = readw(&i2c_base->data);
-#endif
- writew(I2C_STAT_RRDY, &i2c_base->stat);
- }
- if (status & I2C_STAT_ARDY) {
- writew(I2C_STAT_ARDY, &i2c_base->stat);
- break;
- }
+ /* Check for ACK (!NAK) */
+ if (!(status & I2C_STAT_NACK)) {
+ res = 0; /* Device found */
+ udelay(waitdelay);/* Required by AM335X in SPL */
+ /* Abort transfer (force idle state) */
+ writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */
+ udelay(1000);
+ writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_TRX |
+ I2C_CON_STP, &i2c_base->con); /* STP */
}
-
-read_exit:
- flush_fifo();
+pr_exit:
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
- writew(0, &i2c_base->cnt);
- return i2c_error;
+ return res;
}
-static void flush_fifo(void)
-{ u16 stat;
+/*
+ * i2c_read: Function now uses a single I2C read transaction with bulk transfer
+ * of the requested number of bytes (note that the 'i2c md' command
+ * limits this to 16 bytes anyway). If CONFIG_I2C_REPEATED_START is
+ * defined in the board config header, this transaction shall be with
+ * Repeated Start (Sr) between the address and data phases; otherwise
+ * Stop-Start (P-S) shall be used (some I2C chips do require a P-S).
+ * The address (reg offset) may be 0, 1 or 2 bytes long.
+ * Function now reads correctly from chips that return more than one
+ * byte of data per addressed register (like TI temperature sensors),
+ * or that do not need a register address at all (such as some clock
+ * distributors).
+ */
+static int __omap24_i2c_read(struct i2c *i2c_base, int waitdelay, uchar chip,
+ uint addr, int alen, uchar *buffer, int len)
+{
+ int i2c_error = 0;
+ u16 status;
- /* note: if you try and read data when its not there or ready
- * you get a bus error
- */
- while (1) {
- stat = readw(&i2c_base->stat);
- if (stat == I2C_STAT_RRDY) {
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
- defined(CONFIG_OMAP54XX)
- readb(&i2c_base->data);
-#else
- readw(&i2c_base->data);
-#endif
- writew(I2C_STAT_RRDY, &i2c_base->stat);
- udelay(1000);
- } else
- break;
+ if (alen < 0) {
+ puts("I2C read: addr len < 0\n");
+ return 1;
+ }
+ if (len < 0) {
+ puts("I2C read: data len < 0\n");
+ return 1;
+ }
+ if (buffer == NULL) {
+ puts("I2C read: NULL pointer passed\n");
+ return 1;
}
-}
-int i2c_probe(uchar chip)
-{
- u16 status;
- int res = 1; /* default = fail */
+ if (alen > 2) {
+ printf("I2C read: addr len %d not supported\n", alen);
+ return 1;
+ }
- if (chip == readw(&i2c_base->oa))
- return res;
+ if (addr + len > (1 << 16)) {
+ puts("I2C read: address out of range\n");
+ return 1;
+ }
- /* wait until bus not busy */
- if (wait_for_bb())
- return res;
+#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
+ /*
+ * EEPROM chips that implement "address overflow" are ones
+ * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
+ * address and the extra bits end up in the "chip address"
+ * bit slots. This makes a 24WC08 (1Kbyte) chip look like
+ * four 256 byte chips.
+ *
+ * Note that we consider the length of the address field to
+ * still be one byte because the extra address bits are
+ * hidden in the chip address.
+ */
+ if (alen > 0)
+ chip |= ((addr >> (alen * 8)) &
+ CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
+#endif
- /* try to read one byte */
- writew(1, &i2c_base->cnt);
- /* set slave address */
+ /* Wait until bus not busy */
+ if (wait_for_bb(i2c_base, waitdelay))
+ return 1;
+
+ /* Zero, one or two bytes reg address (offset) */
+ writew(alen, &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_STP, &i2c_base->con);
- while (1) {
- status = wait_for_pin();
- if (status == 0 || status & I2C_STAT_AL) {
- res = 1;
- goto probe_exit;
+ if (alen) {
+ /* Must write reg offset first */
+#ifdef CONFIG_I2C_REPEATED_START
+ /* No stop bit, use Repeated Start (Sr) */
+ writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+ I2C_CON_TRX, &i2c_base->con);
+#else
+ /* Stop - Start (P-S) */
+ writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP |
+ I2C_CON_TRX, &i2c_base->con);
+#endif
+ /* Send register offset */
+ while (1) {
+ status = wait_for_event(i2c_base, waitdelay);
+ /* 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 probably not configured (status=0x%x)\n",
+ status);
+ goto rd_exit;
+ }
+ if (status == 0 || (status & I2C_STAT_NACK)) {
+ i2c_error = 1;
+ printf("i2c_read: error waiting for addr ACK (status=0x%x)\n",
+ status);
+ goto rd_exit;
+ }
+ if (alen) {
+ if (status & I2C_STAT_XRDY) {
+ alen--;
+ /* Do we have to use byte access? */
+ writeb((addr >> (8 * alen)) & 0xff,
+ &i2c_base->data);
+ writew(I2C_STAT_XRDY, &i2c_base->stat);
+ }
+ }
+ if (status & I2C_STAT_ARDY) {
+ writew(I2C_STAT_ARDY, &i2c_base->stat);
+ break;
+ }
}
- if (status & I2C_STAT_NACK) {
- res = 1;
- writew(0xff, &i2c_base->stat);
- writew (readw (&i2c_base->con) | I2C_CON_STP, &i2c_base->con);
-
- if (wait_for_bb())
- res = 1;
+ }
+ /* Set slave address */
+ writew(chip, &i2c_base->sa);
+ /* Read len bytes from slave */
+ writew(len, &i2c_base->cnt);
+ /* Need stop bit here */
+ writew(I2C_CON_EN | I2C_CON_MST |
+ I2C_CON_STT | I2C_CON_STP,
+ &i2c_base->con);
- break;
+ /* Receive data */
+ while (1) {
+ status = wait_for_event(i2c_base, waitdelay);
+ /*
+ * Try to identify bus that is not padconf'd for I2C. This
+ * state could be left over from previous transactions if
+ * the address phase is skipped due to alen=0.
+ */
+ if (status == I2C_STAT_XRDY) {
+ i2c_error = 2;
+ printf("i2c_read (data phase): pads on bus probably not configured (status=0x%x)\n",
+ status);
+ goto rd_exit;
}
- if (status & I2C_STAT_ARDY) {
- writew(I2C_STAT_ARDY, &i2c_base->stat);
- break;
+ if (status == 0 || (status & I2C_STAT_NACK)) {
+ i2c_error = 1;
+ goto rd_exit;
}
if (status & I2C_STAT_RRDY) {
- res = 0;
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
- defined(CONFIG_OMAP54XX)
- readb(&i2c_base->data);
-#else
- readw(&i2c_base->data);
-#endif
+ *buffer++ = readb(&i2c_base->data);
writew(I2C_STAT_RRDY, &i2c_base->stat);
}
+ if (status & I2C_STAT_ARDY) {
+ writew(I2C_STAT_ARDY, &i2c_base->stat);
+ break;
+ }
}
-probe_exit:
- flush_fifo();
- /* don't allow any more data in... we don't want it. */
- writew(0, &i2c_base->cnt);
+rd_exit:
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
- return res;
+ return i2c_error;
}
-int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+/* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
+static int __omap24_i2c_write(struct i2c *i2c_base, int waitdelay, uchar chip,
+ uint addr, int alen, uchar *buffer, int len)
{
int i;
+ u16 status;
+ int i2c_error = 0;
+ int timeout = I2C_TIMEOUT;
- if (alen > 2) {
- printf("I2C read: addr len %d not supported\n", alen);
+ if (alen < 0) {
+ puts("I2C write: addr len < 0\n");
return 1;
}
- if (addr + len > (1 << 16)) {
- puts("I2C read: address out of range\n");
+ if (len < 0) {
+ puts("I2C write: data len < 0\n");
return 1;
}
- for (i = 0; i < len; i++) {
- if (i2c_read_byte(chip, addr + i, alen, &buffer[i])) {
- puts("I2C read: I/O error\n");
- i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
- return 1;
- }
+ if (buffer == NULL) {
+ puts("I2C write: NULL pointer passed\n");
+ return 1;
}
- return 0;
-}
-
-int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
-{
- int i;
- u16 status;
- int i2c_error = 0;
- u16 w;
- u8 tmpbuf[2] = {addr >> 8, addr & 0xff};
-
if (alen > 2) {
printf("I2C write: addr len %d not supported\n", alen);
return 1;
if (addr + len > (1 << 16)) {
printf("I2C write: address 0x%x + 0x%x out of range\n",
- addr, len);
+ addr, len);
return 1;
}
- /* wait until bus not busy */
- if (wait_for_bb())
+#ifdef CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW
+ /*
+ * EEPROM chips that implement "address overflow" are ones
+ * like Catalyst 24WC04/08/16 which has 9/10/11 bits of
+ * address and the extra bits end up in the "chip address"
+ * bit slots. This makes a 24WC08 (1Kbyte) chip look like
+ * four 256 byte chips.
+ *
+ * Note that we consider the length of the address field to
+ * still be one byte because the extra address bits are
+ * hidden in the chip address.
+ */
+ if (alen > 0)
+ chip |= ((addr >> (alen * 8)) &
+ CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW);
+#endif
+
+ /* Wait until bus not busy */
+ if (wait_for_bb(i2c_base, waitdelay))
return 1;
- /* start address phase - will write regoffset + len bytes data */
- /* TODO consider case when !CONFIG_OMAP243X/34XX/44XX */
+ /* Start address phase - will write regoffset + len bytes data */
writew(alen + len, &i2c_base->cnt);
- /* set slave address */
+ /* Set slave address */
writew(chip, &i2c_base->sa);
- /* stop bit needed here */
+ /* Stop bit needed here */
writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
- I2C_CON_STP, &i2c_base->con);
-
- /* Send address and data */
- for (i = -alen; i < len; i++) {
- status = wait_for_pin();
-
- if (status == 0 || status & I2C_STAT_NACK) {
+ I2C_CON_STP, &i2c_base->con);
+
+ while (alen) {
+ /* Must write reg offset (one or two bytes) */
+ status = wait_for_event(i2c_base, waitdelay);
+ /* 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 probably not configured (status=0x%x)\n",
+ status);
+ goto wr_exit;
+ }
+ if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
- printf("i2c error waiting for data ACK (status=0x%x)\n",
- status);
- goto write_exit;
+ printf("i2c_write: error waiting for addr ACK (status=0x%x)\n",
+ status);
+ goto wr_exit;
}
-
if (status & I2C_STAT_XRDY) {
- w = (i < 0) ? tmpbuf[2+i] : buffer[i];
-#if !(defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX) || \
- defined(CONFIG_OMAP44XX) || defined(CONFIG_AM33XX) || \
- defined(CONFIG_OMAP54XX))
- w |= ((++i < 0) ? tmpbuf[2+i] : buffer[i]) << 8;
-#endif
- writew(w, &i2c_base->data);
+ alen--;
+ writeb((addr >> (8 * alen)) & 0xff, &i2c_base->data);
writew(I2C_STAT_XRDY, &i2c_base->stat);
} else {
i2c_error = 1;
- printf("i2c bus not ready for Tx (i=%d)\n", i);
- goto write_exit;
+ printf("i2c_write: bus not ready for addr Tx (status=0x%x)\n",
+ status);
+ goto wr_exit;
}
}
+ /* Address phase is over, now write data */
+ for (i = 0; i < len; i++) {
+ status = wait_for_event(i2c_base, waitdelay);
+ 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;
+ }
+ if (status & I2C_STAT_XRDY) {
+ writeb(buffer[i], &i2c_base->data);
+ writew(I2C_STAT_XRDY, &i2c_base->stat);
+ } else {
+ i2c_error = 1;
+ printf("i2c_write: bus not ready for data Tx (i=%d)\n",
+ i);
+ goto wr_exit;
+ }
+ }
+ /*
+ * poll ARDY bit for making sure that last byte really has been
+ * transferred on the bus.
+ */
+ do {
+ status = wait_for_event(i2c_base, waitdelay);
+ } while (!(status & I2C_STAT_ARDY) && timeout--);
+ if (timeout <= 0)
+ printf("i2c_write: timed out writig last byte!\n");
-write_exit:
- flush_fifo();
+wr_exit:
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
return i2c_error;
}
-static int wait_for_bb(void)
+#ifndef CONFIG_DM_I2C
+/*
+ * The legacy I2C functions. These need to get removed once
+ * all users of this driver are converted to DM.
+ */
+static struct i2c *omap24_get_base(struct i2c_adapter *adap)
{
- int timeout = I2C_TIMEOUT;
- u16 stat;
-
- writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/
- while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
- writew(stat, &i2c_base->stat);
- udelay(1000);
+ switch (adap->hwadapnr) {
+ case 0:
+ return (struct i2c *)I2C_BASE1;
+ break;
+ case 1:
+ return (struct i2c *)I2C_BASE2;
+ break;
+#if (CONFIG_SYS_I2C_BUS_MAX > 2)
+ case 2:
+ return (struct i2c *)I2C_BASE3;
+ break;
+#if (CONFIG_SYS_I2C_BUS_MAX > 3)
+ case 3:
+ return (struct i2c *)I2C_BASE4;
+ break;
+#if (CONFIG_SYS_I2C_BUS_MAX > 4)
+ case 4:
+ return (struct i2c *)I2C_BASE5;
+ break;
+#endif
+#endif
+#endif
+ default:
+ printf("wrong hwadapnr: %d\n", adap->hwadapnr);
+ break;
}
+ return NULL;
+}
- if (timeout <= 0) {
- printf("timed out in wait_for_bb: I2C_STAT=%x\n",
- readw(&i2c_base->stat));
- return 1;
- }
- writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
- return 0;
+
+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);
+
+ return __omap24_i2c_read(i2c_base, adap->waitdelay, chip, addr,
+ alen, buffer, len);
}
-static u16 wait_for_pin(void)
+
+static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
+ int alen, uchar *buffer, int len)
{
- u16 status;
- int timeout = I2C_TIMEOUT;
+ struct i2c *i2c_base = omap24_get_base(adap);
- do {
- udelay(1000);
- status = readw(&i2c_base->stat);
- } while (!(status &
- (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
- I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
- I2C_STAT_AL)) && timeout--);
+ return __omap24_i2c_write(i2c_base, adap->waitdelay, chip, addr,
+ alen, buffer, len);
+}
- if (timeout <= 0) {
- printf("timed out in wait_for_pin: I2C_STAT=%x\n",
- readw(&i2c_base->stat));
- writew(0xFFFF, &i2c_base->stat);
- status = 0;
+static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ int ret;
+
+ ret = __omap24_i2c_setspeed(i2c_base, speed, &adap->waitdelay);
+ if (ret) {
+ pr_err("%s: set i2c speed failed\n", __func__);
+ return ret;
}
- return status;
+ adap->speed = speed;
+
+ return 0;
}
-int i2c_set_bus_num(unsigned int bus)
+static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
{
- if ((bus < 0) || (bus >= I2C_BUS_MAX)) {
- printf("Bad bus: %d\n", bus);
- return -1;
- }
+ struct i2c *i2c_base = omap24_get_base(adap);
-#if I2C_BUS_MAX == 4
- if (bus == 3)
- i2c_base = (struct i2c *)I2C_BASE4;
- else
- if (bus == 2)
- i2c_base = (struct i2c *)I2C_BASE3;
- else
+ return __omap24_i2c_init(i2c_base, speed, slaveadd, &adap->waitdelay);
+}
+
+static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+
+ return __omap24_i2c_probe(i2c_base, adap->waitdelay, chip);
+}
+
+#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
+#define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
#endif
-#if I2C_BUS_MAX == 3
- if (bus == 2)
- i2c_base = (struct i2c *)I2C_BASE3;
- else
+#if !defined(CONFIG_SYS_OMAP24_I2C_SLAVE1)
+#define CONFIG_SYS_OMAP24_I2C_SLAVE1 CONFIG_SYS_OMAP24_I2C_SLAVE
#endif
- if (bus == 1)
- i2c_base = (struct i2c *)I2C_BASE2;
- else
- i2c_base = (struct i2c *)I2C_BASE1;
- current_bus = bus;
+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 (CONFIG_SYS_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
+
+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 (CONFIG_SYS_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
+
+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 (CONFIG_SYS_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
+
+#else /* CONFIG_DM_I2C */
+
+static int omap_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
+{
+ struct omap_i2c *priv = dev_get_priv(bus);
+ int ret;
+
+ debug("i2c_xfer: %d messages\n", nmsgs);
+ for (; nmsgs > 0; nmsgs--, msg++) {
+ debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
+ if (msg->flags & I2C_M_RD) {
+ ret = __omap24_i2c_read(priv->regs, priv->waitdelay,
+ msg->addr, 0, 0, msg->buf,
+ msg->len);
+ } else {
+ ret = __omap24_i2c_write(priv->regs, priv->waitdelay,
+ msg->addr, 0, 0, msg->buf,
+ msg->len);
+ }
+ if (ret) {
+ debug("i2c_write: error sending\n");
+ return -EREMOTEIO;
+ }
+ }
+
+ return 0;
+}
- if (!bus_initialized[current_bus])
- i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+static int omap_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+ struct omap_i2c *priv = dev_get_priv(bus);
+
+ priv->speed = speed;
+
+ return __omap24_i2c_setspeed(priv->regs, speed, &priv->waitdelay);
+}
+
+static int omap_i2c_probe_chip(struct udevice *bus, uint chip_addr,
+ uint chip_flags)
+{
+ struct omap_i2c *priv = dev_get_priv(bus);
+
+ return __omap24_i2c_probe(priv->regs, priv->waitdelay, chip_addr);
+}
+
+static int omap_i2c_probe(struct udevice *bus)
+{
+ struct omap_i2c *priv = dev_get_priv(bus);
+
+ __omap24_i2c_init(priv->regs, priv->speed, 0, &priv->waitdelay);
return 0;
}
-int i2c_get_bus_num(void)
+static int omap_i2c_ofdata_to_platdata(struct udevice *bus)
{
- return (int) current_bus;
+ struct omap_i2c *priv = dev_get_priv(bus);
+
+ priv->regs = map_physmem(devfdt_get_addr(bus), sizeof(void *),
+ MAP_NOCACHE);
+ priv->speed = CONFIG_SYS_OMAP24_I2C_SPEED;
+
+ return 0;
}
+
+static const struct dm_i2c_ops omap_i2c_ops = {
+ .xfer = omap_i2c_xfer,
+ .probe_chip = omap_i2c_probe_chip,
+ .set_bus_speed = omap_i2c_set_bus_speed,
+};
+
+static const struct udevice_id omap_i2c_ids[] = {
+ { .compatible = "ti,omap3-i2c" },
+ { .compatible = "ti,omap4-i2c" },
+ { }
+};
+
+U_BOOT_DRIVER(i2c_omap) = {
+ .name = "i2c_omap",
+ .id = UCLASS_I2C,
+ .of_match = omap_i2c_ids,
+ .ofdata_to_platdata = omap_i2c_ofdata_to_platdata,
+ .probe = omap_i2c_probe,
+ .priv_auto_alloc_size = sizeof(struct omap_i2c),
+ .ops = &omap_i2c_ops,
+ .flags = DM_FLAG_PRE_RELOC,
+};
+
+#endif /* CONFIG_DM_I2C */
projects / u-boot / blobdiff