diff options
Diffstat (limited to 'chip/g/usb_upgrade.c')
| -rw-r--r-- | chip/g/usb_upgrade.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/chip/g/usb_upgrade.c b/chip/g/usb_upgrade.c index df3d34ca11..634556cffb 100644 --- a/chip/g/usb_upgrade.c +++ b/chip/g/usb_upgrade.c @@ -97,6 +97,8 @@ static uint32_t block_index; */ static uint64_t prev_activity_timestamp; +#define UPGRADE_PROTOCOL_VERSION 1 + /* Called to deal with data from the host */ static void upgrade_out_handler(struct consumer const *consumer, size_t count) { @@ -124,6 +126,29 @@ static void upgrade_out_handler(struct consumer const *consumer, size_t count) } if (rx_state_ == rx_idle) { + /* + * When responding to the very first packet of the upgrade + * sequence, the original implementation was responding with a + * four byte value, just as to any other block of the transfer + * sequence. + * + * It became clear that there is a need to be able to enhance + * the upgrade protocol, while stayng backwards compatible. To + * achieve that we respond to the very first packet with an 8 + * byte value, the first 4 bytes the same as before, the + * second 4 bytes - the protocol version number. + * + * This way if on the host side receiving of a four byte value + * in response to the first packet is an indication of the + * 'legacy' protocol, version 0. Receiving of an 8 byte + * response would communicate the protocol version in the + * second 4 bytes. + */ + struct { + uint32_t value; + uint32_t version; + } startup_resp; + /* This better be the first block, of zero size. */ if (count != sizeof(struct update_pdu_header)) { CPRINTS("FW update: wrong first block size %d", @@ -140,15 +165,19 @@ static void upgrade_out_handler(struct consumer const *consumer, size_t count) &resp_size); if (resp_size == 4) { - resp_value = updu.resp; /* Already in network order. */ + /* Already in network order. */ + startup_resp.value = updu.resp; rx_state_ = rx_outside_block; } else { /* This must be a single byte error code. */ - resp_value = htobe32(*((uint8_t *)&updu.resp)); + startup_resp.value = htobe32(*((uint8_t *)&updu.resp)); } + + startup_resp.version = htobe32(UPGRADE_PROTOCOL_VERSION); + /* Let the host know what upgrader had to say. */ - QUEUE_ADD_UNITS(&upgrade_to_usb, &resp_value, - sizeof(resp_value)); + QUEUE_ADD_UNITS(&upgrade_to_usb, &startup_resp, + sizeof(startup_resp)); return; } |