#include <common.h>
#include <asm/arch/clock.h>
#include <asm/arch/imx-regs.h>
-#include <asm/errno.h>
-#include <asm/imx-common/mxc_i2c.h>
+#include <linux/errno.h>
+#include <asm/mach-imx/mxc_i2c.h>
#include <asm/io.h>
#include <i2c.h>
#include <watchdog.h>
#include <dm.h>
+#include <dm/pinctrl.h>
#include <fdtdec.h>
DECLARE_GLOBAL_DATA_PTR;
#define IMX_I2C_REGSHIFT 2
#define VF610_I2C_REGSHIFT 0
+
+#define I2C_EARLY_INIT_INDEX 0
+#ifdef CONFIG_SYS_I2C_IFDR_DIV
+#define I2C_IFDR_DIV_CONSERVATIVE CONFIG_SYS_I2C_IFDR_DIV
+#else
+#define I2C_IFDR_DIV_CONSERVATIVE 0x7e
+#endif
+
/* Register index */
#define IADR 0
#define IFDR 1
#define I2SR_IIF_CLEAR (0 << 1)
#endif
-#if defined(CONFIG_HARD_I2C) && !defined(CONFIG_SYS_I2C_BASE)
-#error "define CONFIG_SYS_I2C_BASE to use the mxc_i2c driver"
-#endif
-
#ifdef I2C_QUIRK_REG
static u16 i2c_clk_div[60][2] = {
{ 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 },
int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
if (!base)
- return -ENODEV;
+ return -EINVAL;
/* Store divider value */
writeb(idx, base + (IFDR << reg_shift));
if (ret < 0)
return ret;
if (ret & I2SR_RX_NO_AK)
- return -ENODEV;
+ return -EREMOTEIO;
return 0;
}
temp |= I2CR_MTX | I2CR_TX_NO_AK;
writeb(temp, base + (I2CR << reg_shift));
- /* write slave address */
- ret = tx_byte(i2c_bus, chip << 1);
- if (ret < 0)
- return ret;
-
- while (alen--) {
- ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
+ if (alen >= 0) {
+ /* write slave address */
+ ret = tx_byte(i2c_bus, chip << 1);
if (ret < 0)
return ret;
+
+ while (alen--) {
+ ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
+ if (ret < 0)
+ return ret;
+ }
}
+
return 0;
}
}
#else
/*
- * Since pinmux is not supported, implement a weak function here.
- * You can implement your i2c_bus_idle in board file. When pinctrl
- * is supported, this can be removed.
+ * See Linux Documentation/devicetree/bindings/i2c/i2c-imx.txt
+ * "
+ * scl-gpios: specify the gpio related to SCL pin
+ * sda-gpios: specify the gpio related to SDA pin
+ * add pinctrl to configure i2c pins to gpio function for i2c
+ * bus recovery, call it "gpio" state
+ * "
+ *
+ * The i2c_idle_bus is an implementation following Linux Kernel.
*/
-int __i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
+int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
{
- return 0;
-}
+ struct udevice *bus = i2c_bus->bus;
+ struct gpio_desc *scl_gpio = &i2c_bus->scl_gpio;
+ struct gpio_desc *sda_gpio = &i2c_bus->sda_gpio;
+ int sda, scl;
+ int i, ret = 0;
+ ulong elapsed, start_time;
-int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
- __attribute__((weak, alias("__i2c_idle_bus")));
+ if (pinctrl_select_state(bus, "gpio")) {
+ dev_dbg(bus, "Can not to switch to use gpio pinmux\n");
+ /*
+ * GPIO pinctrl for i2c force idle is not a must,
+ * but it is strongly recommended to be used.
+ * Because it can help you to recover from bad
+ * i2c bus state. Do not return failure, because
+ * it is not a must.
+ */
+ return 0;
+ }
+
+ dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
+ dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
+ scl = dm_gpio_get_value(scl_gpio);
+ sda = dm_gpio_get_value(sda_gpio);
+
+ if ((sda & scl) == 1)
+ goto exit; /* Bus is idle already */
+
+ /* Send high and low on the SCL line */
+ for (i = 0; i < 9; i++) {
+ dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_OUT);
+ dm_gpio_set_value(scl_gpio, 0);
+ udelay(50);
+ dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
+ udelay(50);
+ }
+ start_time = get_timer(0);
+ for (;;) {
+ dm_gpio_set_dir_flags(scl_gpio, GPIOD_IS_IN);
+ dm_gpio_set_dir_flags(sda_gpio, GPIOD_IS_IN);
+ scl = dm_gpio_get_value(scl_gpio);
+ sda = dm_gpio_get_value(sda_gpio);
+ if ((sda & scl) == 1)
+ break;
+ WATCHDOG_RESET();
+ elapsed = get_timer(start_time);
+ if (elapsed > (CONFIG_SYS_HZ / 5)) { /* .2 seconds */
+ ret = -EBUSY;
+ printf("%s: failed to clear bus, sda=%d scl=%d\n", __func__, sda, scl);
+ break;
+ }
+ }
+
+exit:
+ pinctrl_select_state(bus, "default");
+ return ret;
+}
#endif
static int i2c_init_transfer(struct mxc_i2c_bus *i2c_bus, u8 chip,
VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
if (!i2c_bus->base)
- return -ENODEV;
+ return -EINVAL;
for (retry = 0; retry < 3; retry++) {
ret = i2c_init_transfer_(i2c_bus, chip, addr, alen);
if (ret >= 0)
return 0;
i2c_imx_stop(i2c_bus);
- if (ret == -ENODEV)
+ if (ret == -EREMOTEIO)
return ret;
printf("%s: failed for chip 0x%x retry=%d\n", __func__, chip,
if (ret < 0)
return ret;
- temp = readb(base + (I2CR << reg_shift));
- temp |= I2CR_RSTA;
- writeb(temp, base + (I2CR << reg_shift));
+ if (alen >= 0) {
+ temp = readb(base + (I2CR << reg_shift));
+ temp |= I2CR_RSTA;
+ writeb(temp, base + (I2CR << reg_shift));
+ }
ret = tx_byte(i2c_bus, (chip << 1) | 1);
if (ret < 0) {
#endif
static struct mxc_i2c_bus mxc_i2c_buses[] = {
-#if defined(CONFIG_LS102XA) || defined(CONFIG_FSL_LSCH3)
+#if defined(CONFIG_ARCH_LS1021A) || defined(CONFIG_VF610) || \
+ defined(CONFIG_FSL_LAYERSCAPE)
{ 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
{ 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
{ 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
return;
}
- mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
- mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
+ /*
+ * Warning: Be careful to allow the assignment to a static
+ * variable here. This function could be called while U-Boot is
+ * still running in flash memory. So such assignment is equal
+ * to write data to flash without erasing.
+ */
+ if (idle_bus_fn)
+ mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
+ if (idle_bus_data)
+ mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
ret = enable_i2c_clk(1, index);
if (ret < 0) {
bus_i2c_set_bus_speed(&mxc_i2c_buses[index], speed);
}
+/*
+ * Early init I2C for prepare read the clk through I2C.
+ */
+void i2c_early_init_f(void)
+{
+ ulong base = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].base;
+ bool quirk = mxc_i2c_buses[I2C_EARLY_INIT_INDEX].driver_data
+ & I2C_QUIRK_FLAG ? true : false;
+ int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+
+ /* Set I2C divider value */
+ writeb(I2C_IFDR_DIV_CONSERVATIVE, base + (IFDR << reg_shift));
+ /* Reset module */
+ writeb(I2CR_IDIS, base + (I2CR << reg_shift));
+ writeb(0, base + (I2SR << reg_shift));
+ /* Enable I2C */
+ writeb(I2CR_IEN, base + (I2CR << reg_shift));
+}
+
/*
* Init I2C Bus
*/
/*
* Register mxc i2c adapters
*/
+#ifdef CONFIG_SYS_I2C_MXC_I2C1
U_BOOT_I2C_ADAP_COMPLETE(mxc0, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C1_SPEED,
CONFIG_SYS_MXC_I2C1_SLAVE, 0)
+#endif
+
+#ifdef CONFIG_SYS_I2C_MXC_I2C2
U_BOOT_I2C_ADAP_COMPLETE(mxc1, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
mxc_i2c_set_bus_speed,
CONFIG_SYS_MXC_I2C2_SPEED,
CONFIG_SYS_MXC_I2C2_SLAVE, 1)
+#endif
+
#ifdef CONFIG_SYS_I2C_MXC_I2C3
U_BOOT_I2C_ADAP_COMPLETE(mxc2, mxc_i2c_init, mxc_i2c_probe,
mxc_i2c_read, mxc_i2c_write,
static int mxc_i2c_probe(struct udevice *bus)
{
struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
+ const void *fdt = gd->fdt_blob;
+ int node = dev_of_offset(bus);
fdt_addr_t addr;
- int ret;
+ int ret, ret2;
i2c_bus->driver_data = dev_get_driver_data(bus);
- addr = dev_get_addr(bus);
+ addr = devfdt_get_addr(bus);
if (addr == FDT_ADDR_T_NONE)
- return -ENODEV;
+ return -EINVAL;
i2c_bus->base = addr;
i2c_bus->index = bus->seq;
+ i2c_bus->bus = bus;
/* Enable clk */
ret = enable_i2c_clk(1, bus->seq);
if (ret < 0)
return ret;
+ /*
+ * See Documentation/devicetree/bindings/i2c/i2c-imx.txt
+ * Use gpio to force bus idle when necessary.
+ */
+ ret = fdt_stringlist_search(fdt, node, "pinctrl-names", "gpio");
+ if (ret < 0) {
+ debug("i2c bus %d at 0x%2lx, no gpio pinctrl state.\n", bus->seq, i2c_bus->base);
+ } else {
+ ret = gpio_request_by_name_nodev(offset_to_ofnode(node),
+ "scl-gpios", 0, &i2c_bus->scl_gpio,
+ GPIOD_IS_OUT);
+ ret2 = gpio_request_by_name_nodev(offset_to_ofnode(node),
+ "sda-gpios", 0, &i2c_bus->sda_gpio,
+ GPIOD_IS_OUT);
+ if (!dm_gpio_is_valid(&i2c_bus->sda_gpio) ||
+ !dm_gpio_is_valid(&i2c_bus->scl_gpio) ||
+ ret || ret2) {
+ dev_err(dev, "i2c bus %d at %lu, fail to request scl/sda gpio\n", bus->seq, i2c_bus->base);
+ return -EINVAL;
+ }
+ }
+
ret = i2c_idle_bus(i2c_bus);
if (ret < 0) {
/* Disable clk */