From e9b25f2ea1ef24a648f07feeb3604888bdca43e0 Mon Sep 17 00:00:00 2001 From: Moritz Fischer Date: Thu, 12 Jan 2017 09:47:30 -0800 Subject: cros_ec: i2c: Group i2c write / read into single transaction Replace dm_i2c_write() / dm_i2c_read() with transaction using struct i2c_msg[2] in order to allow for i2c controller to detect write/read cycle to emit a repeated start condition. Signed-off-by: Moritz Fischer Cc: Simon Glass Cc: u-boot@lists.denx.de Acked-by: Simon Glass Tested on snow: Tested-by: Simon Glass --- drivers/misc/cros_ec_i2c.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'drivers/misc/cros_ec_i2c.c') diff --git a/drivers/misc/cros_ec_i2c.c b/drivers/misc/cros_ec_i2c.c index 3de18b2d2ad..f2f6961499b 100644 --- a/drivers/misc/cros_ec_i2c.c +++ b/drivers/misc/cros_ec_i2c.c @@ -29,6 +29,8 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd, 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_platdata(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 */ @@ -53,6 +55,11 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd, 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. @@ -85,24 +92,21 @@ static int cros_ec_i2c_command(struct udevice *udev, uint8_t cmd, *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_write(udev, 0, dev->dout, out_bytes); + + ret = dm_i2c_xfer(udev, &i2c_msg[0], 2); if (ret) { - debug("%s: Cannot complete I2C write to %s\n", __func__, + debug("%s: Could not execute transfer to %s\n", __func__, udev->name); ret = -1; } - if (!ret) { - ret = dm_i2c_read(udev, 0, in_ptr, in_bytes); - if (ret) { - debug("%s: Cannot complete I2C read from %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; -- cgit v1.2.3 From 147f785f6737a900d82acd0297a82399f9cba006 Mon Sep 17 00:00:00 2001 From: Moritz Fischer Date: Fri, 20 Jan 2017 12:35:03 -0800 Subject: cros_ec: i2c: Add support for version 3 of the EC protocol Add support for version 3 of the ec protocol. It basically works by stitching some additional header in front (special command code), and having a result and packet_length stitched on for the reply. Signed-off-by: Moritz Fischer Cc: Simon Glass Cc: u-boot@lists.denx.de Acked-by: Simon Glass Tested on snow: Tested-by: Simon Glass --- drivers/misc/cros_ec_i2c.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) (limited to 'drivers/misc/cros_ec_i2c.c') diff --git a/drivers/misc/cros_ec_i2c.c b/drivers/misc/cros_ec_i2c.c index f2f6961499b..6e0934017a3 100644 --- a/drivers/misc/cros_ec_i2c.c +++ b/drivers/misc/cros_ec_i2c.c @@ -24,6 +24,89 @@ #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_platdata(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) @@ -140,6 +223,7 @@ static int cros_ec_probe(struct udevice *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[] = { -- cgit v1.2.3