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authorAaron Durbin <adurbin@chromium.org>2014-08-06 14:38:52 -0500
committerPatrick Georgi <pgeorgi@google.com>2015-03-21 10:43:30 +0100
commitaee78f0dbe3ee9984c8c1b8969a0a4b97c4e5d16 (patch)
treeffe863497e7912cc551325dfd8d6a97fd75e20ea /src/ec/google/chromeec
parent828272767d067cc215ff6c7dc93bd731a1a61765 (diff)
chromeec: provide proto v3 over i2c support
Certain boards need to speak proto v3 over i2c. Leverage the transport agnostic API to share the logic with other proto v3 impelementations. BUG=chrome-os-partner:31148 BRANCH=None TEST=Built and ran on ryu. Can talk to the EC successfully. Change-Id: I1d0cd6907057af4ded3c4460193bbe1d897a1db7 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: cb9ac965ad04c9491f40fd9aa595176a28a467b3 Original-Change-Id: Ib699120fd232392e8caa0889c2bf40f4587a8a35 Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/211139 Original-Reviewed-by: Stefan Reinauer <reinauer@google.com> Original-Reviewed-by: Tom Warren <twarren@nvidia.com> Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org> Original-Tested-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: http://review.coreboot.org/8828 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/ec/google/chromeec')
-rw-r--r--src/ec/google/chromeec/Kconfig7
-rw-r--r--src/ec/google/chromeec/ec_i2c.c107
2 files changed, 114 insertions, 0 deletions
diff --git a/src/ec/google/chromeec/Kconfig b/src/ec/google/chromeec/Kconfig
index cad1b487bd..bec12fb10a 100644
--- a/src/ec/google/chromeec/Kconfig
+++ b/src/ec/google/chromeec/Kconfig
@@ -19,6 +19,13 @@ config EC_GOOGLE_CHROMEEC_I2C_CHIP
hex
default 0x1e
+config EC_GOOGLE_CHROMEEC_I2C_PROTO3
+ depends on EC_GOOGLE_CHROMEEC_I2C
+ bool
+ default n
+ help
+ Use only proto3 for i2c EC communication.
+
config EC_GOOGLE_CHROMEEC_LPC
depends on EC_GOOGLE_CHROMEEC && ARCH_X86 # Needs Plug-and-play.
def_bool y
diff --git a/src/ec/google/chromeec/ec_i2c.c b/src/ec/google/chromeec/ec_i2c.c
index 551c3b9a87..03e2b365a1 100644
--- a/src/ec/google/chromeec/ec_i2c.c
+++ b/src/ec/google/chromeec/ec_i2c.c
@@ -27,6 +27,111 @@
#include "ec.h"
#include "ec_commands.h"
+#if IS_ENABLED(CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3)
+
+#define PROTO3_FRAMING_BYTES sizeof(uint32_t)
+/* Just use the LPC host packet size to size the buffer. */
+#define PROTO3_MAX_PACKET_SIZE 268
+
+struct proto3_i2c_buf {
+ uint8_t framing_bytes[PROTO3_FRAMING_BYTES];
+ uint8_t data[PROTO3_MAX_PACKET_SIZE];
+} __attribute__((aligned(sizeof(uint32_t))));
+
+static struct proto3_i2c_buf req_buf;
+static struct proto3_i2c_buf resp_buf;
+
+enum {
+ CMD_INDEX,
+ RESP_INDEX,
+ SEGS_PER_CMD,
+};
+
+struct i2c_ec {
+ int bus;
+ struct i2c_seg segs[SEGS_PER_CMD];
+};
+
+static struct i2c_ec ec_dev = {
+ .bus = CONFIG_EC_GOOGLE_CHROMEEC_I2C_BUS,
+ .segs[CMD_INDEX] = {
+ .read = 0,
+ .chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP,
+ /* Framing byte to be transferred prior to request. */
+ .buf = &req_buf.framing_bytes[3],
+ },
+ .segs[RESP_INDEX] = {
+ .read = 1,
+ .chip = CONFIG_EC_GOOGLE_CHROMEEC_I2C_CHIP,
+ /* return code and total length before full response. */
+ .buf = &resp_buf.framing_bytes[2],
+ },
+};
+
+void *crosec_get_buffer(size_t size, int req)
+{
+ struct proto3_i2c_buf *ib;
+
+ if (size > PROTO3_MAX_PACKET_SIZE) {
+ printk(BIOS_DEBUG, "Proto v3 buffer request too large: %zu!\n",
+ size);
+ return NULL;
+ }
+
+ if (req)
+ ib = &req_buf;
+ else
+ ib = &resp_buf;
+
+ return &ib->data[0];
+}
+
+static int crosec_i2c_io(size_t req_size, size_t resp_size, void *context)
+{
+ struct i2c_ec *ec = context;
+ uint8_t ret_code;
+ size_t resp_len;
+
+ if (req_size > PROTO3_MAX_PACKET_SIZE ||
+ resp_size > PROTO3_MAX_PACKET_SIZE)
+ return -1;
+
+ /* Place the framing byte and set size accordingly. */
+ ec->segs[CMD_INDEX].len = req_size + 1;
+ ec->segs[CMD_INDEX].buf[0] = EC_COMMAND_PROTOCOL_3;
+ /* Return code and length returned prior to packet data. */
+ ec->segs[RESP_INDEX].len = resp_size + 2;
+
+ if (i2c_transfer(ec->bus, ec->segs, ARRAY_SIZE(ec->segs)) != 0) {
+ printk(BIOS_ERR, "%s: Cannot complete read from i2c-%d:%#x\n",
+ __func__, ec->bus, ec->segs[0].chip);
+ return -1;
+ }
+
+ ret_code = ec->segs[RESP_INDEX].buf[0];
+ resp_len = ec->segs[RESP_INDEX].buf[1];
+
+ if (ret_code != 0) {
+ printk(BIOS_ERR, "EC command returned 0x%x\n", ret_code);
+ return -1;
+ }
+
+ if (resp_len > resp_size) {
+ printk(BIOS_ERR, "Response length mismatch %zu vs %zu\n",
+ resp_len, resp_size);
+ return -1;
+ }
+
+ return 0;
+}
+
+int google_chromeec_command(struct chromeec_command *cec_command)
+{
+ return crosec_command_proto(cec_command, crosec_i2c_io, &ec_dev);
+}
+
+#else /* CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3 */
+
/* Command (host->device) format for I2C:
* uint8_t version, cmd, len, data[len], checksum;
*
@@ -151,6 +256,8 @@ int google_chromeec_command(struct chromeec_command *cec_command)
return 0;
}
+#endif /* CONFIG_EC_GOOGLE_CHROMEEC_I2C_PROTO3 */
+
#ifndef __PRE_RAM__
u8 google_chromeec_get_event(void)
{