diff options
Diffstat (limited to 'roms/u-boot/drivers/i2c/i2c-uclass.c')
-rw-r--r-- | roms/u-boot/drivers/i2c/i2c-uclass.c | 735 |
1 files changed, 735 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/i2c/i2c-uclass.c b/roms/u-boot/drivers/i2c/i2c-uclass.c new file mode 100644 index 000000000..be5678521 --- /dev/null +++ b/roms/u-boot/drivers/i2c/i2c-uclass.c @@ -0,0 +1,735 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) 2014 Google, Inc + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <i2c.h> +#include <log.h> +#include <malloc.h> +#include <acpi/acpi_device.h> +#include <dm/acpi.h> +#include <dm/device-internal.h> +#include <dm/lists.h> +#include <dm/pinctrl.h> +#if CONFIG_IS_ENABLED(DM_GPIO) +#include <asm/gpio.h> +#endif +#include <linux/delay.h> +#include "acpi_i2c.h" + +#define I2C_MAX_OFFSET_LEN 4 + +enum { + PIN_SDA = 0, + PIN_SCL, + PIN_COUNT, +}; + +/* Useful debugging function */ +void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs) +{ + int i; + + for (i = 0; i < nmsgs; i++) { + struct i2c_msg *m = &msg[i]; + + printf(" %s %x len=%x", m->flags & I2C_M_RD ? "R" : "W", + msg->addr, msg->len); + if (!(m->flags & I2C_M_RD)) + printf(": %x", m->buf[0]); + printf("\n"); + } +} + +/** + * i2c_setup_offset() - Set up a new message with a chip offset + * + * @chip: Chip to use + * @offset: Byte offset within chip + * @offset_buf: Place to put byte offset + * @msg: Message buffer + * @return 0 if OK, -EADDRNOTAVAIL if the offset length is 0. In that case the + * message is still set up but will not contain an offset. + */ +static int i2c_setup_offset(struct dm_i2c_chip *chip, uint offset, + uint8_t offset_buf[], struct i2c_msg *msg) +{ + int offset_len = chip->offset_len; + + msg->addr = chip->chip_addr; + if (chip->chip_addr_offset_mask) + msg->addr |= (offset >> (8 * offset_len)) & + chip->chip_addr_offset_mask; + msg->flags = chip->flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0; + msg->len = chip->offset_len; + msg->buf = offset_buf; + if (!offset_len) + return -EADDRNOTAVAIL; + assert(offset_len <= I2C_MAX_OFFSET_LEN); + + while (offset_len--) + *offset_buf++ = offset >> (8 * offset_len); + + return 0; +} + +static int i2c_read_bytewise(struct udevice *dev, uint offset, + uint8_t *buffer, int len) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + struct udevice *bus = dev_get_parent(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct i2c_msg msg[2], *ptr; + uint8_t offset_buf[I2C_MAX_OFFSET_LEN]; + int ret; + int i; + + for (i = 0; i < len; i++) { + if (i2c_setup_offset(chip, offset + i, offset_buf, msg)) + return -EINVAL; + ptr = msg + 1; + ptr->addr = msg->addr; + ptr->flags = msg->flags | I2C_M_RD; + ptr->len = 1; + ptr->buf = &buffer[i]; + ptr++; + + ret = ops->xfer(bus, msg, ptr - msg); + if (ret) + return ret; + } + + return 0; +} + +static int i2c_write_bytewise(struct udevice *dev, uint offset, + const uint8_t *buffer, int len) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + struct udevice *bus = dev_get_parent(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct i2c_msg msg[1]; + uint8_t buf[I2C_MAX_OFFSET_LEN + 1]; + int ret; + int i; + + for (i = 0; i < len; i++) { + if (i2c_setup_offset(chip, offset + i, buf, msg)) + return -EINVAL; + buf[msg->len++] = buffer[i]; + + ret = ops->xfer(bus, msg, 1); + if (ret) + return ret; + } + + return 0; +} + +int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + struct udevice *bus = dev_get_parent(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct i2c_msg msg[2], *ptr; + uint8_t offset_buf[I2C_MAX_OFFSET_LEN]; + int msg_count; + + if (!ops->xfer) + return -ENOSYS; + if (chip->flags & DM_I2C_CHIP_RD_ADDRESS) + return i2c_read_bytewise(dev, offset, buffer, len); + ptr = msg; + if (!i2c_setup_offset(chip, offset, offset_buf, ptr)) + ptr++; + + if (len) { + ptr->addr = msg->addr; + ptr->flags = chip->flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0; + ptr->flags |= I2C_M_RD; + ptr->len = len; + ptr->buf = buffer; + ptr++; + } + msg_count = ptr - msg; + + return ops->xfer(bus, msg, msg_count); +} + +int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer, + int len) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + struct udevice *bus = dev_get_parent(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct i2c_msg msg[1]; + + if (!ops->xfer) + return -ENOSYS; + + if (chip->flags & DM_I2C_CHIP_WR_ADDRESS) + return i2c_write_bytewise(dev, offset, buffer, len); + /* + * The simple approach would be to send two messages here: one to + * set the offset and one to write the bytes. However some drivers + * will not be expecting this, and some chips won't like how the + * driver presents this on the I2C bus. + * + * The API does not support separate offset and data. We could extend + * it with a flag indicating that there is data in the next message + * that needs to be processed in the same transaction. We could + * instead add an additional buffer to each message. For now, handle + * this in the uclass since it isn't clear what the impact on drivers + * would be with this extra complication. Unfortunately this means + * copying the message. + * + * Use the stack for small messages, malloc() for larger ones. We + * need to allow space for the offset (up to 4 bytes) and the message + * itself. + */ + if (len < 64) { + uint8_t buf[I2C_MAX_OFFSET_LEN + len]; + + i2c_setup_offset(chip, offset, buf, msg); + msg->len += len; + memcpy(buf + chip->offset_len, buffer, len); + + return ops->xfer(bus, msg, 1); + } else { + uint8_t *buf; + int ret; + + buf = malloc(I2C_MAX_OFFSET_LEN + len); + if (!buf) + return -ENOMEM; + i2c_setup_offset(chip, offset, buf, msg); + msg->len += len; + memcpy(buf + chip->offset_len, buffer, len); + + ret = ops->xfer(bus, msg, 1); + free(buf); + return ret; + } +} + +int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs) +{ + struct udevice *bus = dev_get_parent(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + + if (!ops->xfer) + return -ENOSYS; + + return ops->xfer(bus, msg, nmsgs); +} + +int dm_i2c_reg_read(struct udevice *dev, uint offset) +{ + uint8_t val; + int ret; + + ret = dm_i2c_read(dev, offset, &val, 1); + if (ret < 0) + return ret; + + return val; +} + +int dm_i2c_reg_write(struct udevice *dev, uint offset, uint value) +{ + uint8_t val = value; + + return dm_i2c_write(dev, offset, &val, 1); +} + +/** + * i2c_probe_chip() - probe for a chip on a bus + * + * @bus: Bus to probe + * @chip_addr: Chip address to probe + * @flags: Flags for the chip + * @return 0 if found, -ENOSYS if the driver is invalid, -EREMOTEIO if the chip + * does not respond to probe + */ +static int i2c_probe_chip(struct udevice *bus, uint chip_addr, + enum dm_i2c_chip_flags chip_flags) +{ + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct i2c_msg msg[1]; + int ret; + + if (ops->probe_chip) { + ret = ops->probe_chip(bus, chip_addr, chip_flags); + if (!ret || ret != -ENOSYS) + return ret; + } + + if (!ops->xfer) + return -ENOSYS; + + /* Probe with a zero-length message */ + msg->addr = chip_addr; + msg->flags = chip_flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0; + msg->len = 0; + msg->buf = NULL; + + return ops->xfer(bus, msg, 1); +} + +static int i2c_bind_driver(struct udevice *bus, uint chip_addr, uint offset_len, + struct udevice **devp) +{ + struct dm_i2c_chip *chip; + char name[30], *str; + struct udevice *dev; + int ret; + + snprintf(name, sizeof(name), "generic_%x", chip_addr); + str = strdup(name); + if (!str) + return -ENOMEM; + ret = device_bind_driver(bus, "i2c_generic_chip_drv", str, &dev); + debug("%s: device_bind_driver: ret=%d\n", __func__, ret); + if (ret) + goto err_bind; + + /* Tell the device what we know about it */ + chip = dev_get_parent_plat(dev); + chip->chip_addr = chip_addr; + chip->offset_len = offset_len; + ret = device_probe(dev); + debug("%s: device_probe: ret=%d\n", __func__, ret); + if (ret) + goto err_probe; + + *devp = dev; + return 0; + +err_probe: + /* + * If the device failed to probe, unbind it. There is nothing there + * on the bus so we don't want to leave it lying around + */ + device_unbind(dev); +err_bind: + free(str); + return ret; +} + +int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len, + struct udevice **devp) +{ + struct udevice *dev; + + debug("%s: Searching bus '%s' for address %02x: ", __func__, + bus->name, chip_addr); + for (device_find_first_child(bus, &dev); dev; + device_find_next_child(&dev)) { + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + int ret; + + if (chip->chip_addr == (chip_addr & + ~chip->chip_addr_offset_mask)) { + ret = device_probe(dev); + debug("found, ret=%d\n", ret); + if (ret) + return ret; + *devp = dev; + return 0; + } + } + debug("not found\n"); + return i2c_bind_driver(bus, chip_addr, offset_len, devp); +} + +int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len, + struct udevice **devp) +{ + struct udevice *bus; + int ret; + + ret = uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus); + if (ret) { + debug("Cannot find I2C bus %d\n", busnum); + return ret; + } + + /* detect the presence of the chip on the bus */ + ret = i2c_probe_chip(bus, chip_addr, 0); + debug("%s: bus='%s', address %02x, ret=%d\n", __func__, bus->name, + chip_addr, ret); + if (ret) { + debug("Cannot detect I2C chip %02x on bus %d\n", chip_addr, + busnum); + return ret; + } + + ret = i2c_get_chip(bus, chip_addr, offset_len, devp); + if (ret) { + debug("Cannot find I2C chip %02x on bus %d\n", chip_addr, + busnum); + return ret; + } + + return 0; +} + +int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags, + struct udevice **devp) +{ + int ret; + + *devp = NULL; + + /* First probe that chip */ + ret = i2c_probe_chip(bus, chip_addr, chip_flags); + debug("%s: bus='%s', address %02x, ret=%d\n", __func__, bus->name, + chip_addr, ret); + if (ret) + return ret; + + /* The chip was found, see if we have a driver, and probe it */ + ret = i2c_get_chip(bus, chip_addr, 1, devp); + debug("%s: i2c_get_chip: ret=%d\n", __func__, ret); + + return ret; +} + +int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) +{ + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus); + int ret; + + /* + * If we have a method, call it. If not then the driver probably wants + * to deal with speed changes on the next transfer. It can easily read + * the current speed from this uclass + */ + if (ops->set_bus_speed) { + ret = ops->set_bus_speed(bus, speed); + if (ret) + return ret; + } + i2c->speed_hz = speed; + + return 0; +} + +int dm_i2c_get_bus_speed(struct udevice *bus) +{ + struct dm_i2c_ops *ops = i2c_get_ops(bus); + struct dm_i2c_bus *i2c = dev_get_uclass_priv(bus); + + if (!ops->get_bus_speed) + return i2c->speed_hz; + + return ops->get_bus_speed(bus); +} + +int i2c_set_chip_flags(struct udevice *dev, uint flags) +{ + struct udevice *bus = dev->parent; + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + struct dm_i2c_ops *ops = i2c_get_ops(bus); + int ret; + + if (ops->set_flags) { + ret = ops->set_flags(dev, flags); + if (ret) + return ret; + } + chip->flags = flags; + + return 0; +} + +int i2c_get_chip_flags(struct udevice *dev, uint *flagsp) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + + *flagsp = chip->flags; + + return 0; +} + +int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + + if (offset_len > I2C_MAX_OFFSET_LEN) + return log_ret(-EINVAL); + chip->offset_len = offset_len; + + return 0; +} + +int i2c_get_chip_offset_len(struct udevice *dev) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + + return chip->offset_len; +} + +int i2c_set_chip_addr_offset_mask(struct udevice *dev, uint mask) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + + chip->chip_addr_offset_mask = mask; + + return 0; +} + +uint i2c_get_chip_addr_offset_mask(struct udevice *dev) +{ + struct dm_i2c_chip *chip = dev_get_parent_plat(dev); + + return chip->chip_addr_offset_mask; +} + +#if CONFIG_IS_ENABLED(DM_GPIO) +static void i2c_gpio_set_pin(struct gpio_desc *pin, int bit) +{ + if (bit) + dm_gpio_set_dir_flags(pin, GPIOD_IS_IN); + else + dm_gpio_set_dir_flags(pin, GPIOD_IS_OUT | + GPIOD_ACTIVE_LOW | + GPIOD_IS_OUT_ACTIVE); +} + +static int i2c_gpio_get_pin(struct gpio_desc *pin) +{ + return dm_gpio_get_value(pin); +} + +int i2c_deblock_gpio_loop(struct gpio_desc *sda_pin, + struct gpio_desc *scl_pin, + unsigned int scl_count, + unsigned int start_count, + unsigned int delay) +{ + int i, ret = -EREMOTEIO; + + i2c_gpio_set_pin(sda_pin, 1); + i2c_gpio_set_pin(scl_pin, 1); + udelay(delay); + + /* Toggle SCL until slave release SDA */ + for (; scl_count; --scl_count) { + i2c_gpio_set_pin(scl_pin, 1); + udelay(delay); + i2c_gpio_set_pin(scl_pin, 0); + udelay(delay); + if (i2c_gpio_get_pin(sda_pin)) { + ret = 0; + break; + } + } + + if (!ret && start_count) { + for (i = 0; i < start_count; i++) { + /* Send start condition */ + udelay(delay); + i2c_gpio_set_pin(sda_pin, 1); + udelay(delay); + i2c_gpio_set_pin(scl_pin, 1); + udelay(delay); + i2c_gpio_set_pin(sda_pin, 0); + udelay(delay); + i2c_gpio_set_pin(scl_pin, 0); + } + } + + /* Then, send I2C stop */ + i2c_gpio_set_pin(sda_pin, 0); + udelay(delay); + + i2c_gpio_set_pin(scl_pin, 1); + udelay(delay); + + i2c_gpio_set_pin(sda_pin, 1); + udelay(delay); + + if (!i2c_gpio_get_pin(sda_pin) || !i2c_gpio_get_pin(scl_pin)) + ret = -EREMOTEIO; + + return ret; +} + +static int i2c_deblock_gpio(struct udevice *bus) +{ + struct gpio_desc gpios[PIN_COUNT]; + int ret, ret0; + + ret = gpio_request_list_by_name(bus, "gpios", gpios, + ARRAY_SIZE(gpios), GPIOD_IS_IN); + if (ret != ARRAY_SIZE(gpios)) { + debug("%s: I2C Node '%s' has no 'gpios' property %s\n", + __func__, dev_read_name(bus), bus->name); + if (ret >= 0) { + gpio_free_list(bus, gpios, ret); + ret = -ENOENT; + } + goto out; + } + + ret = pinctrl_select_state(bus, "gpio"); + if (ret) { + debug("%s: I2C Node '%s' has no 'gpio' pinctrl state. %s\n", + __func__, dev_read_name(bus), bus->name); + goto out_no_pinctrl; + } + + ret0 = i2c_deblock_gpio_loop(&gpios[PIN_SDA], &gpios[PIN_SCL], 9, 0, 5); + + ret = pinctrl_select_state(bus, "default"); + if (ret) { + debug("%s: I2C Node '%s' has no 'default' pinctrl state. %s\n", + __func__, dev_read_name(bus), bus->name); + } + + ret = !ret ? ret0 : ret; + +out_no_pinctrl: + gpio_free_list(bus, gpios, ARRAY_SIZE(gpios)); +out: + return ret; +} +#else +static int i2c_deblock_gpio(struct udevice *bus) +{ + return -ENOSYS; +} +#endif /* DM_GPIO */ + +int i2c_deblock(struct udevice *bus) +{ + struct dm_i2c_ops *ops = i2c_get_ops(bus); + + if (!ops->deblock) + return i2c_deblock_gpio(bus); + + return ops->deblock(bus); +} + +#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) +int i2c_chip_of_to_plat(struct udevice *dev, struct dm_i2c_chip *chip) +{ + int addr; + + chip->offset_len = dev_read_u32_default(dev, "u-boot,i2c-offset-len", + 1); + chip->flags = 0; + addr = dev_read_u32_default(dev, "reg", -1); + if (addr == -1) { + debug("%s: I2C Node '%s' has no 'reg' property %s\n", __func__, + dev_read_name(dev), dev->name); + return log_ret(-EINVAL); + } + chip->chip_addr = addr; + + return 0; +} +#endif + +static int i2c_pre_probe(struct udevice *dev) +{ +#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) + struct dm_i2c_bus *i2c = dev_get_uclass_priv(dev); + unsigned int max = 0; + ofnode node; + int ret; + + i2c->max_transaction_bytes = 0; + dev_for_each_subnode(node, dev) { + ret = ofnode_read_u32(node, + "u-boot,i2c-transaction-bytes", + &max); + if (!ret && max > i2c->max_transaction_bytes) + i2c->max_transaction_bytes = max; + } + + debug("%s: I2C bus: %s max transaction bytes: %d\n", __func__, + dev->name, i2c->max_transaction_bytes); +#endif + return 0; +} + +static int i2c_post_probe(struct udevice *dev) +{ +#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) + struct dm_i2c_bus *i2c = dev_get_uclass_priv(dev); + + i2c->speed_hz = dev_read_u32_default(dev, "clock-frequency", + I2C_SPEED_STANDARD_RATE); + + return dm_i2c_set_bus_speed(dev, i2c->speed_hz); +#else + return 0; +#endif +} + +static int i2c_child_post_bind(struct udevice *dev) +{ +#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) + struct dm_i2c_chip *plat = dev_get_parent_plat(dev); + + if (!dev_has_ofnode(dev)) + return 0; + return i2c_chip_of_to_plat(dev, plat); +#else + return 0; +#endif +} + +static int i2c_post_bind(struct udevice *dev) +{ + int ret = 0; + + debug("%s: %s, seq=%d\n", __func__, dev->name, dev_seq(dev)); + +#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA) + ret = dm_scan_fdt_dev(dev); +#endif + return ret; +} + +UCLASS_DRIVER(i2c) = { + .id = UCLASS_I2C, + .name = "i2c", + .flags = DM_UC_FLAG_SEQ_ALIAS, + .post_bind = i2c_post_bind, + .pre_probe = i2c_pre_probe, + .post_probe = i2c_post_probe, + .per_device_auto = sizeof(struct dm_i2c_bus), + .per_child_plat_auto = sizeof(struct dm_i2c_chip), + .child_post_bind = i2c_child_post_bind, +}; + +UCLASS_DRIVER(i2c_generic) = { + .id = UCLASS_I2C_GENERIC, + .name = "i2c_generic", +}; + +static const struct udevice_id generic_chip_i2c_ids[] = { + { .compatible = "i2c-chip", .data = I2C_DEVICE_GENERIC }, +#if CONFIG_IS_ENABLED(ACPIGEN) + { .compatible = "hid-over-i2c", .data = I2C_DEVICE_HID_OVER_I2C }, +#endif + { } +}; + +U_BOOT_DRIVER(i2c_generic_chip_drv) = { + .name = "i2c_generic_chip_drv", + .id = UCLASS_I2C_GENERIC, + .of_match = generic_chip_i2c_ids, +#if CONFIG_IS_ENABLED(ACPIGEN) + .of_to_plat = acpi_i2c_of_to_plat, + .priv_auto = sizeof(struct acpi_i2c_priv), +#endif + ACPI_OPS_PTR(&acpi_i2c_ops) +}; |