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author | 2023-10-10 14:33:42 +0000 | |
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committer | 2023-10-10 14:33:42 +0000 | |
commit | af1a266670d040d2f4083ff309d732d648afba2a (patch) | |
tree | 2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/u-boot/drivers/misc/cros_ec_i2c.c | |
parent | e02cda008591317b1625707ff8e115a4841aa889 (diff) |
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/u-boot/drivers/misc/cros_ec_i2c.c')
-rw-r--r-- | roms/u-boot/drivers/misc/cros_ec_i2c.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/misc/cros_ec_i2c.c b/roms/u-boot/drivers/misc/cros_ec_i2c.c new file mode 100644 index 000000000..a1b78a304 --- /dev/null +++ b/roms/u-boot/drivers/misc/cros_ec_i2c.c @@ -0,0 +1,240 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Chromium OS cros_ec driver - I2C interface + * + * Copyright (c) 2012 The Chromium OS Authors. + */ + +/* + * The Matrix Keyboard Protocol driver handles talking to the keyboard + * controller chip. Mostly this is for keyboard functions, but some other + * things have slipped in, so we provide generic services to talk to the + * KBC. + */ + +#include <common.h> +#include <dm.h> +#include <i2c.h> +#include <cros_ec.h> +#include <log.h> + +#ifdef DEBUG_TRACE +#define debug_trace(fmt, b...) debug(fmt, #b) +#else +#define debug_trace(fmt, b...) +#endif + +/** + * Request format for protocol v3 + * byte 0 0xda (EC_COMMAND_PROTOCOL_3) + * byte 1-8 struct ec_host_request + * byte 10- response data + */ +struct ec_host_request_i2c { + /* Always 0xda to backward compatible with v2 struct */ + uint8_t command_protocol; + struct ec_host_request ec_request; +} __packed; + +/* + * Response format for protocol v3 + * byte 0 result code + * byte 1 packet_length + * byte 2-9 struct ec_host_response + * byte 10- response data + */ +struct ec_host_response_i2c { + uint8_t result; + uint8_t packet_length; + struct ec_host_response ec_response; +} __packed; + +static int cros_ec_i2c_packet(struct udevice *udev, int out_bytes, int in_bytes) +{ + struct cros_ec_dev *dev = dev_get_uclass_priv(udev); + struct dm_i2c_chip *chip = dev_get_parent_plat(udev); + struct ec_host_request_i2c *ec_request_i2c = + (struct ec_host_request_i2c *)dev->dout; + struct ec_host_response_i2c *ec_response_i2c = + (struct ec_host_response_i2c *)dev->din; + struct i2c_msg i2c_msg[2]; + int ret; + + i2c_msg[0].addr = chip->chip_addr; + i2c_msg[0].flags = 0; + i2c_msg[1].addr = chip->chip_addr; + i2c_msg[1].flags = I2C_M_RD; + + /* one extra byte, to indicate v3 */ + i2c_msg[0].len = out_bytes + 1; + i2c_msg[0].buf = dev->dout; + + /* stitch on EC_COMMAND_PROTOCOL_3 */ + memmove(&ec_request_i2c->ec_request, dev->dout, out_bytes); + ec_request_i2c->command_protocol = EC_COMMAND_PROTOCOL_3; + + /* two extra bytes for v3 */ + i2c_msg[1].len = in_bytes + 2; + i2c_msg[1].buf = dev->din; + + ret = dm_i2c_xfer(udev, &i2c_msg[0], 2); + if (ret) { + printf("%s: Could not execute transfer: %d\n", __func__, ret); + return ret; + } + + /* When we send a v3 request to v2 ec, ec won't recognize the 0xda + * (EC_COMMAND_PROTOCOL_3) and will return with status + * EC_RES_INVALID_COMMAND with zero data length + * + * In case of invalid command for v3 protocol the data length + * will be at least sizeof(struct ec_host_response) + */ + if (ec_response_i2c->result == EC_RES_INVALID_COMMAND && + ec_response_i2c->packet_length == 0) + return -EPROTONOSUPPORT; + + if (ec_response_i2c->packet_length < sizeof(struct ec_host_response)) { + printf("%s: response of %u bytes too short; not a full hdr\n", + __func__, ec_response_i2c->packet_length); + return -EBADMSG; + } + + + /* drop result and packet_len */ + memmove(dev->din, &ec_response_i2c->ec_response, in_bytes); + + return in_bytes; +} + +static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd, + int cmd_version, const uint8_t *dout, + int dout_len, uint8_t **dinp, int din_len) +{ + struct cros_ec_dev *dev = dev_get_uclass_priv(udev); + struct dm_i2c_chip *chip = dev_get_parent_plat(udev); + struct i2c_msg i2c_msg[2]; + /* version8, cmd8, arglen8, out8[dout_len], csum8 */ + int out_bytes = dout_len + 4; + /* response8, arglen8, in8[din_len], checksum8 */ + int in_bytes = din_len + 3; + uint8_t *ptr; + /* Receive input data, so that args will be dword aligned */ + uint8_t *in_ptr; + int len, csum, ret; + + /* + * Sanity-check I/O sizes given transaction overhead in internal + * buffers. + */ + if (out_bytes > sizeof(dev->dout)) { + debug("%s: Cannot send %d bytes\n", __func__, dout_len); + return -1; + } + if (in_bytes > sizeof(dev->din)) { + debug("%s: Cannot receive %d bytes\n", __func__, din_len); + return -1; + } + assert(dout_len >= 0); + assert(dinp); + + i2c_msg[0].addr = chip->chip_addr; + i2c_msg[0].len = out_bytes; + i2c_msg[0].buf = dev->dout; + i2c_msg[0].flags = 0; + + /* + * Copy command and data into output buffer so we can do a single I2C + * burst transaction. + */ + ptr = dev->dout; + + /* + * in_ptr starts of pointing to a dword-aligned input data buffer. + * We decrement it back by the number of header bytes we expect to + * receive, so that the first parameter of the resulting input data + * will be dword aligned. + */ + in_ptr = dev->din + sizeof(int64_t); + + if (dev->protocol_version != 2) { + /* Something we don't support */ + debug("%s: Protocol version %d unsupported\n", + __func__, dev->protocol_version); + return -1; + } + + *ptr++ = EC_CMD_VERSION0 + cmd_version; + *ptr++ = cmd; + *ptr++ = dout_len; + in_ptr -= 2; /* Expect status, length bytes */ + + memcpy(ptr, dout, dout_len); + ptr += dout_len; + + *ptr++ = (uint8_t) + cros_ec_calc_checksum(dev->dout, dout_len + 3); + + i2c_msg[1].addr = chip->chip_addr; + i2c_msg[1].len = in_bytes; + i2c_msg[1].buf = in_ptr; + i2c_msg[1].flags = I2C_M_RD; + + /* Send output data */ + cros_ec_dump_data("out", -1, dev->dout, out_bytes); + + ret = dm_i2c_xfer(udev, &i2c_msg[0], 2); + if (ret) { + debug("%s: Could not execute transfer to %s\n", __func__, + udev->name); + ret = -1; + } + + if (*in_ptr != EC_RES_SUCCESS) { + debug("%s: Received bad result code %d\n", __func__, *in_ptr); + return -(int)*in_ptr; + } + + len = in_ptr[1]; + if (len + 3 > sizeof(dev->din)) { + debug("%s: Received length %#02x too large\n", + __func__, len); + return -1; + } + csum = cros_ec_calc_checksum(in_ptr, 2 + len); + if (csum != in_ptr[2 + len]) { + debug("%s: Invalid checksum rx %#02x, calced %#02x\n", + __func__, in_ptr[2 + din_len], csum); + return -1; + } + din_len = min(din_len, len); + cros_ec_dump_data("in", -1, in_ptr, din_len + 3); + + /* Return pointer to dword-aligned input data, if any */ + *dinp = dev->din + sizeof(int64_t); + + return din_len; +} + +static int cros_ec_probe(struct udevice *dev) +{ + return cros_ec_register(dev); +} + +static struct dm_cros_ec_ops cros_ec_ops = { + .command = cros_ec_i2c_command, + .packet = cros_ec_i2c_packet, +}; + +static const struct udevice_id cros_ec_ids[] = { + { .compatible = "google,cros-ec-i2c" }, + { } +}; + +U_BOOT_DRIVER(google_cros_ec_i2c) = { + .name = "google_cros_ec_i2c", + .id = UCLASS_CROS_EC, + .of_match = cros_ec_ids, + .probe = cros_ec_probe, + .ops = &cros_ec_ops, +}; |