--- /dev/null
+/*
+ * TI DaVinci (TMS320DM644x) I2C driver.
+ *
+ * (C) Copyright 2012-2014
+ * Texas Instruments Incorporated, <www.ti.com>
+ * (C) Copyright 2007 Sergey Kubushyn <ksi@koi8.net>
+ * --------------------------------------------------------
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/i2c_defs.h>
+#include <asm/io.h>
+#include "davinci_i2c.h"
+
+#define CHECK_NACK() \
+ do {\
+ if (tmp & (I2C_TIMEOUT | I2C_STAT_NACK)) {\
+ REG(&(i2c_base->i2c_con)) = 0;\
+ return 1;\
+ } \
+ } while (0)
+
+static struct i2c_regs *davinci_get_base(struct i2c_adapter *adap);
+
+static int wait_for_bus(struct i2c_adapter *adap)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ int stat, timeout;
+
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+
+ for (timeout = 0; timeout < 10; timeout++) {
+ stat = REG(&(i2c_base->i2c_stat));
+ if (!((stat) & I2C_STAT_BB)) {
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ return 0;
+ }
+
+ REG(&(i2c_base->i2c_stat)) = stat;
+ udelay(50000);
+ }
+
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ return 1;
+}
+
+
+static int poll_i2c_irq(struct i2c_adapter *adap, int mask)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ int stat, timeout;
+
+ for (timeout = 0; timeout < 10; timeout++) {
+ udelay(1000);
+ stat = REG(&(i2c_base->i2c_stat));
+ if (stat & mask)
+ return stat;
+ }
+
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ return stat | I2C_TIMEOUT;
+}
+
+static void flush_rx(struct i2c_adapter *adap)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+
+ while (1) {
+ if (!(REG(&(i2c_base->i2c_stat)) & I2C_STAT_RRDY))
+ break;
+
+ REG(&(i2c_base->i2c_drr));
+ REG(&(i2c_base->i2c_stat)) = I2C_STAT_RRDY;
+ udelay(1000);
+ }
+}
+
+static uint davinci_i2c_setspeed(struct i2c_adapter *adap, uint speed)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ uint32_t div, psc;
+
+ psc = 2;
+ /* SCLL + SCLH */
+ div = (CONFIG_SYS_HZ_CLOCK / ((psc + 1) * speed)) - 10;
+ REG(&(i2c_base->i2c_psc)) = psc; /* 27MHz / (2 + 1) = 9MHz */
+ REG(&(i2c_base->i2c_scll)) = (div * 50) / 100; /* 50% Duty */
+ REG(&(i2c_base->i2c_sclh)) = div - REG(&(i2c_base->i2c_scll));
+
+ adap->speed = speed;
+ return 0;
+}
+
+static void davinci_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+
+ if (REG(&(i2c_base->i2c_con)) & I2C_CON_EN) {
+ REG(&(i2c_base->i2c_con)) = 0;
+ udelay(50000);
+ }
+
+ davinci_i2c_setspeed(adap, speed);
+
+ REG(&(i2c_base->i2c_oa)) = slaveadd;
+ REG(&(i2c_base->i2c_cnt)) = 0;
+
+ /* Interrupts must be enabled or I2C module won't work */
+ REG(&(i2c_base->i2c_ie)) = I2C_IE_SCD_IE | I2C_IE_XRDY_IE |
+ I2C_IE_RRDY_IE | I2C_IE_ARDY_IE | I2C_IE_NACK_IE;
+
+ /* Now enable I2C controller (get it out of reset) */
+ REG(&(i2c_base->i2c_con)) = I2C_CON_EN;
+
+ udelay(1000);
+}
+
+static int davinci_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ int rc = 1;
+
+ if (chip == REG(&(i2c_base->i2c_oa)))
+ return rc;
+
+ REG(&(i2c_base->i2c_con)) = 0;
+ if (wait_for_bus(adap))
+ return 1;
+
+ /* try to read one byte from current (or only) address */
+ REG(&(i2c_base->i2c_cnt)) = 1;
+ REG(&(i2c_base->i2c_sa)) = chip;
+ REG(&(i2c_base->i2c_con)) = (I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+ I2C_CON_STP);
+ udelay(50000);
+
+ if (!(REG(&(i2c_base->i2c_stat)) & I2C_STAT_NACK)) {
+ rc = 0;
+ flush_rx(adap);
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ } else {
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ REG(&(i2c_base->i2c_con)) |= I2C_CON_STP;
+ udelay(20000);
+ if (wait_for_bus(adap))
+ return 1;
+ }
+
+ flush_rx(adap);
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ REG(&(i2c_base->i2c_cnt)) = 0;
+ return rc;
+}
+
+static int davinci_i2c_read(struct i2c_adapter *adap, uint8_t chip,
+ uint32_t addr, int alen, uint8_t *buf, int len)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ uint32_t tmp;
+ int i;
+
+ if ((alen < 0) || (alen > 2)) {
+ printf("%s(): bogus address length %x\n", __func__, alen);
+ return 1;
+ }
+
+ if (wait_for_bus(adap))
+ return 1;
+
+ if (alen != 0) {
+ /* Start address phase */
+ tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX;
+ REG(&(i2c_base->i2c_cnt)) = alen;
+ REG(&(i2c_base->i2c_sa)) = chip;
+ REG(&(i2c_base->i2c_con)) = tmp;
+
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ switch (alen) {
+ case 2:
+ /* Send address MSByte */
+ if (tmp & I2C_STAT_XRDY) {
+ REG(&(i2c_base->i2c_dxr)) = (addr >> 8) & 0xff;
+ } else {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY | I2C_STAT_NACK);
+
+ CHECK_NACK();
+ /* No break, fall through */
+ case 1:
+ /* Send address LSByte */
+ if (tmp & I2C_STAT_XRDY) {
+ REG(&(i2c_base->i2c_dxr)) = addr & 0xff;
+ } else {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY |
+ I2C_STAT_NACK | I2C_STAT_ARDY);
+
+ CHECK_NACK();
+
+ if (!(tmp & I2C_STAT_ARDY)) {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+ }
+ }
+
+ /* Address phase is over, now read 'len' bytes and stop */
+ tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_STP;
+ REG(&(i2c_base->i2c_cnt)) = len & 0xffff;
+ REG(&(i2c_base->i2c_sa)) = chip;
+ REG(&(i2c_base->i2c_con)) = tmp;
+
+ for (i = 0; i < len; i++) {
+ tmp = poll_i2c_irq(adap, I2C_STAT_RRDY | I2C_STAT_NACK |
+ I2C_STAT_ROVR);
+
+ CHECK_NACK();
+
+ if (tmp & I2C_STAT_RRDY) {
+ buf[i] = REG(&(i2c_base->i2c_drr));
+ } else {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+ }
+
+ tmp = poll_i2c_irq(adap, I2C_STAT_SCD | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ if (!(tmp & I2C_STAT_SCD)) {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+
+ flush_rx(adap);
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ REG(&(i2c_base->i2c_cnt)) = 0;
+ REG(&(i2c_base->i2c_con)) = 0;
+
+ return 0;
+}
+
+static int davinci_i2c_write(struct i2c_adapter *adap, uint8_t chip,
+ uint32_t addr, int alen, uint8_t *buf, int len)
+{
+ struct i2c_regs *i2c_base = davinci_get_base(adap);
+ uint32_t tmp;
+ int i;
+
+ if ((alen < 0) || (alen > 2)) {
+ printf("%s(): bogus address length %x\n", __func__, alen);
+ return 1;
+ }
+ if (len < 0) {
+ printf("%s(): bogus length %x\n", __func__, len);
+ return 1;
+ }
+
+ if (wait_for_bus(adap))
+ return 1;
+
+ /* Start address phase */
+ tmp = I2C_CON_EN | I2C_CON_MST | I2C_CON_STT |
+ I2C_CON_TRX | I2C_CON_STP;
+ REG(&(i2c_base->i2c_cnt)) = (alen == 0) ?
+ len & 0xffff : (len & 0xffff) + alen;
+ REG(&(i2c_base->i2c_sa)) = chip;
+ REG(&(i2c_base->i2c_con)) = tmp;
+
+ switch (alen) {
+ case 2:
+ /* Send address MSByte */
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ if (tmp & I2C_STAT_XRDY) {
+ REG(&(i2c_base->i2c_dxr)) = (addr >> 8) & 0xff;
+ } else {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+ /* No break, fall through */
+ case 1:
+ /* Send address LSByte */
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ if (tmp & I2C_STAT_XRDY) {
+ REG(&(i2c_base->i2c_dxr)) = addr & 0xff;
+ } else {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+ }
+
+ for (i = 0; i < len; i++) {
+ tmp = poll_i2c_irq(adap, I2C_STAT_XRDY | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ if (tmp & I2C_STAT_XRDY)
+ REG(&(i2c_base->i2c_dxr)) = buf[i];
+ else
+ return 1;
+ }
+
+ tmp = poll_i2c_irq(adap, I2C_STAT_SCD | I2C_STAT_NACK);
+
+ CHECK_NACK();
+
+ if (!(tmp & I2C_STAT_SCD)) {
+ REG(&(i2c_base->i2c_con)) = 0;
+ return 1;
+ }
+
+ flush_rx(adap);
+ REG(&(i2c_base->i2c_stat)) = 0xffff;
+ REG(&(i2c_base->i2c_cnt)) = 0;
+ REG(&(i2c_base->i2c_con)) = 0;
+
+ return 0;
+}
+
+static struct i2c_regs *davinci_get_base(struct i2c_adapter *adap)
+{
+ switch (adap->hwadapnr) {
+#if I2C_BUS_MAX >= 3
+ case 2:
+ return (struct i2c_regs *)I2C2_BASE;
+#endif
+#if I2C_BUS_MAX >= 2
+ case 1:
+ return (struct i2c_regs *)I2C1_BASE;
+#endif
+ case 0:
+ return (struct i2c_regs *)I2C_BASE;
+
+ default:
+ printf("wrong hwadapnr: %d\n", adap->hwadapnr);
+ }
+
+ return NULL;
+}
+
+U_BOOT_I2C_ADAP_COMPLETE(davinci_0, davinci_i2c_init, davinci_i2c_probe,
+ davinci_i2c_read, davinci_i2c_write,
+ davinci_i2c_setspeed,
+ CONFIG_SYS_DAVINCI_I2C_SPEED,
+ CONFIG_SYS_DAVINCI_I2C_SLAVE,
+ 0)
+
+#if I2C_BUS_MAX >= 2
+U_BOOT_I2C_ADAP_COMPLETE(davinci_1, davinci_i2c_init, davinci_i2c_probe,
+ davinci_i2c_read, davinci_i2c_write,
+ davinci_i2c_setspeed,
+ CONFIG_SYS_DAVINCI_I2C_SPEED1,
+ CONFIG_SYS_DAVINCI_I2C_SLAVE1,
+ 1)
+#endif
+
+#if I2C_BUS_MAX >= 3
+U_BOOT_I2C_ADAP_COMPLETE(davinci_2, davinci_i2c_init, davinci_i2c_probe,
+ davinci_i2c_read, davinci_i2c_write,
+ davinci_i2c_setspeed,
+ CONFIG_SYS_DAVINCI_I2C_SPEED2,
+ CONFIG_SYS_DAVINCI_I2C_SLAVE2,
+ 2)
+#endif
Code Review / kvmfornfv.git / blobdiff