Refactor API for host commands, and handle variable length data better

Added version mask field to DECLARE_HOST_COMMAND() because it's
convenient to do so when I'm touching all host command
implementations, but all commands simply declare version 0 and nothing
checks it yet.  Will add version support in a followup CL.

This change is internal to the EC; it does not change the data sent
over the host interface.

BUG=chrome-os-partner:11275
TEST=manual

ectool version && ectool echash; should get sane data from both

ectool flashread 0x80 0x40 /tmp/foo && od -tx1 /tmp/foo
should match data from offset 0x80 of ec.bin (od -j128 -n64 -tx1 ec.bin)

Change-Id: I5699f72b8d5e1ac23929353c9a34158d76c44206
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/27172
Reviewed-by: Bill Richardson <wfrichar@chromium.org>

1 files changed, 23 insertions, 22 deletions

diff --git a/common/pstore_commands.c b/common/pstore_commands.c
index fdd0eaf26c..9717d3ccdb 100644
--- a/common/pstore_commands.c
+++ b/common/pstore_commands.c
@@ -5,42 +5,40 @@
 
 /* Persistent storage commands for Chrome EC */
 
-#include "board.h"
+#include "common.h"
 #include "eeprom.h"
 #include "host_command.h"
 #include "util.h"
 
-
-int pstore_command_get_info(uint8_t *data, int *resp_size)
+int pstore_command_get_info(struct host_cmd_handler_args *args)
 {
 	struct ec_response_pstore_info *r =
-			(struct ec_response_pstore_info *)data;
+			(struct ec_response_pstore_info *)args->response;
 
 	ASSERT(EEPROM_BLOCK_START_PSTORE + EEPROM_BLOCK_COUNT_PSTORE <=
 	       eeprom_get_block_count());
 
 	r->pstore_size = EEPROM_BLOCK_COUNT_PSTORE * eeprom_get_block_size();
 	r->access_size = sizeof(uint32_t);
-	*resp_size = sizeof(struct ec_response_pstore_info);
+	args->response_size = sizeof(*r);
 	return EC_RES_SUCCESS;
 }
-DECLARE_HOST_COMMAND(EC_CMD_PSTORE_INFO, pstore_command_get_info);
-
+DECLARE_HOST_COMMAND(EC_CMD_PSTORE_INFO,
+		     pstore_command_get_info,
+		     EC_VER_MASK(0));
 
-int pstore_command_read(uint8_t *data, int *resp_size)
+int pstore_command_read(struct host_cmd_handler_args *args)
 {
-	struct ec_params_pstore_read *p =
-			(struct ec_params_pstore_read *)data;
-	struct ec_response_pstore_read *r =
-			(struct ec_response_pstore_read *)data;
-	char *dest = r->data;
+	const struct ec_params_pstore_read *p =
+			(const struct ec_params_pstore_read *)args->params;
+	char *dest = args->response;
 	int block_size = eeprom_get_block_size();
 	int block = p->offset / block_size + EEPROM_BLOCK_COUNT_PSTORE;
 	int offset = p->offset % block_size;
 	int bytes_left = p->size;
 
-	if (p->size > sizeof(r->data))
-		return EC_RES_ERROR;
+	if (p->size > sizeof(EC_PARAM_SIZE))
+		return EC_RES_INVALID_PARAM;
 
 	while (bytes_left) {
 		/* Read what we can from the current block */
@@ -60,16 +58,17 @@ int pstore_command_read(uint8_t *data, int *resp_size)
 		dest += bytes_this;
 	}
 
-	*resp_size = sizeof(struct ec_response_pstore_read);
+	args->response_size = p->size;
 	return EC_RES_SUCCESS;
 }
-DECLARE_HOST_COMMAND(EC_CMD_PSTORE_READ, pstore_command_read);
-
+DECLARE_HOST_COMMAND(EC_CMD_PSTORE_READ,
+		     pstore_command_read,
+		     EC_VER_MASK(0));
 
-int pstore_command_write(uint8_t *data, int *resp_size)
+int pstore_command_write(struct host_cmd_handler_args *args)
 {
-	struct ec_params_pstore_write *p =
-			(struct ec_params_pstore_write *)data;
+	const struct ec_params_pstore_write *p =
+			(const struct ec_params_pstore_write *)args->params;
 
 	const char *src = p->data;
 	int block_size = eeprom_get_block_size();
@@ -100,4 +99,6 @@ int pstore_command_write(uint8_t *data, int *resp_size)
 
 	return EC_RES_SUCCESS;
 }
-DECLARE_HOST_COMMAND(EC_CMD_PSTORE_WRITE, pstore_command_write);
+DECLARE_HOST_COMMAND(EC_CMD_PSTORE_WRITE,
+		     pstore_command_write,
+		     EC_VER_MASK(0));