ectool prefers /dev/cros_ec, then falls back to i2c, lpc

This is preparation for the common userspace EC interface. If/when that
appears, this will be ready.

BUG=chromium:239197
BRANCH=all
TEST=manual

Build, install, run it. Shouldn't be any change.

Change-Id: I9fa78515ec5443ba659f10a66bbaadcb7f4802b0
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/56131

1 files changed, 77 insertions, 78 deletions

diff --git a/util/comm-lpc.c b/util/comm-lpc.c
index dbae5a7ecc..3548f4eb29 100644
--- a/util/comm-lpc.c
+++ b/util/comm-lpc.c
@@ -14,59 +14,6 @@
 #define INITIAL_UDELAY 5     /* 5 us */
 #define MAXIMUM_UDELAY 10000 /* 10 ms */
 
-int comm_init(void)
-{
-	int i;
-	int byte = 0xff;
-
-	/* Request I/O privilege */
-	if (iopl(3) < 0) {
-		perror("Error getting I/O privilege");
-		return -3;
-	}
-
-	/*
-	 * Test if the I/O port has been configured for Chromium EC LPC
-	 * interface.  If all the bytes are 0xff, very likely that Chromium EC
-	 * is not present.
-	 *
-	 * TODO: (crosbug.com/p/10963) Should only need to look at the command
-	 * byte, since we don't support ACPI burst mode and thus bit 4 should
-	 * be 0.
-	 */
-	byte &= inb(EC_LPC_ADDR_HOST_CMD);
-	byte &= inb(EC_LPC_ADDR_HOST_DATA);
-	for (i = 0; i < EC_HOST_PARAM_SIZE && byte == 0xff; ++i)
-		byte &= inb(EC_LPC_ADDR_HOST_PARAM + i);
-	if (byte == 0xff) {
-		fprintf(stderr, "Port 0x%x,0x%x,0x%x-0x%x are all 0xFF.\n",
-			EC_LPC_ADDR_HOST_CMD, EC_LPC_ADDR_HOST_DATA,
-			EC_LPC_ADDR_HOST_PARAM,
-			EC_LPC_ADDR_HOST_PARAM + EC_HOST_PARAM_SIZE - 1);
-		fprintf(stderr,
-			"Very likely this board doesn't have a Chromium EC.\n");
-		return -4;
-	}
-
-	/*
-	 * Test if LPC command args are supported.
-	 *
-	 * The cheapest way to do this is by looking for the memory-mapped
-	 * flag.  This is faster than sending a new-style 'hello' command and
-	 * seeing whether the EC sets the EC_HOST_ARGS_FLAG_FROM_HOST flag
-	 * in args when it responds.
-	 */
-	if (inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID) != 'E' ||
-	    inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID + 1) != 'C' ||
-	    !(inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_HOST_CMD_FLAGS) &
-	      EC_HOST_CMD_FLAG_LPC_ARGS_SUPPORTED)) {
-		fprintf(stderr, "EC doesn't support command args.\n");
-		return -5;
-	}
-
-	return 0;
-}
-
 /*
  * Wait for the EC to be unbusy.  Returns 0 if unbusy, non-zero if
  * timeout.
@@ -97,9 +44,10 @@ static int wait_for_ec(int status_addr, int timeout_usec)
 	return -1;  /* Timeout */
 }
 
-int ec_command(int command, int version, const void *indata, int insize,
-	       void *outdata, int outsize) {
-
+static int ec_command_lpc(int command, int version,
+			  const void *outdata, int outsize,
+			  void *indata, int insize)
+{
 	struct ec_lpc_host_args args;
 	const uint8_t *d;
 	uint8_t *dout;
@@ -109,13 +57,13 @@ int ec_command(int command, int version, const void *indata, int insize,
 	/* Fill in args */
 	args.flags = EC_HOST_ARGS_FLAG_FROM_HOST;
 	args.command_version = version;
-	args.data_size = insize;
+	args.data_size = outsize;
 
 	/* Initialize checksum */
 	csum = command + args.flags + args.command_version + args.data_size;
 
 	/* Write data and update checksum */
-	for (i = 0, d = (uint8_t *)indata; i < insize; i++, d++) {
+	for (i = 0, d = (uint8_t *)outdata; i < outsize; i++, d++) {
 		outb(*d, EC_LPC_ADDR_HOST_PARAM + i);
 		csum += *d;
 	}
@@ -153,7 +101,7 @@ int ec_command(int command, int version, const void *indata, int insize,
 		return -EC_RES_INVALID_RESPONSE;
 	}
 
-	if (args.data_size > outsize) {
+	if (args.data_size > insize) {
 		fprintf(stderr, "EC returned too much data\n");
 		return -EC_RES_INVALID_RESPONSE;
 	}
@@ -162,7 +110,7 @@ int ec_command(int command, int version, const void *indata, int insize,
 	csum = command + args.flags + args.command_version + args.data_size;
 
 	/* Read response and update checksum */
-	for (i = 0, dout = (uint8_t *)outdata; i < args.data_size;
+	for (i = 0, dout = (uint8_t *)indata; i < args.data_size;
 	     i++, dout++) {
 		*dout = inb(EC_LPC_ADDR_HOST_PARAM + i);
 		csum += *dout;
@@ -179,31 +127,82 @@ int ec_command(int command, int version, const void *indata, int insize,
 }
 
 
-uint8_t read_mapped_mem8(uint8_t offset)
+static int ec_readmem_lpc(int offset, int bytes, void *dest)
 {
-	return inb(EC_LPC_ADDR_MEMMAP + offset);
-}
+	int i = offset;
+	char *s = dest;
+	int cnt = 0;
+
+	if (offset >= EC_MEMMAP_SIZE - bytes)
+		return -1;
+
+	if (bytes) {				/* fixed length */
+		for (; cnt < bytes; i++, s++, cnt++)
+			*s = inb(EC_LPC_ADDR_MEMMAP + i);
+	} else {				/* string */
+		for (; i < EC_MEMMAP_SIZE; i++, s++) {
+			*s = inb(EC_LPC_ADDR_MEMMAP + i);
+			cnt++;
+			if (!*s)
+				break;
+		}
+	}
 
-uint16_t read_mapped_mem16(uint8_t offset)
-{
-	return inw(EC_LPC_ADDR_MEMMAP + offset);
+	return cnt;
 }
 
-uint32_t read_mapped_mem32(uint8_t offset)
+int comm_init_lpc(void)
 {
-	return inl(EC_LPC_ADDR_MEMMAP + offset);
-}
+	int i;
+	int byte = 0xff;
 
-int read_mapped_string(uint8_t offset, char *buf)
-{
-	int c;
+	/* Request I/O privilege */
+	if (iopl(3) < 0) {
+		perror("Error getting I/O privilege");
+		return -3;
+	}
+
+	/*
+	 * Test if the I/O port has been configured for Chromium EC LPC
+	 * interface.  If all the bytes are 0xff, very likely that Chromium EC
+	 * is not present.
+	 *
+	 * TODO: (crosbug.com/p/10963) Should only need to look at the command
+	 * byte, since we don't support ACPI burst mode and thus bit 4 should
+	 * be 0.
+	 */
+	byte &= inb(EC_LPC_ADDR_HOST_CMD);
+	byte &= inb(EC_LPC_ADDR_HOST_DATA);
+	for (i = 0; i < EC_HOST_PARAM_SIZE && byte == 0xff; ++i)
+		byte &= inb(EC_LPC_ADDR_HOST_PARAM + i);
+	if (byte == 0xff) {
+		fprintf(stderr, "Port 0x%x,0x%x,0x%x-0x%x are all 0xFF.\n",
+			EC_LPC_ADDR_HOST_CMD, EC_LPC_ADDR_HOST_DATA,
+			EC_LPC_ADDR_HOST_PARAM,
+			EC_LPC_ADDR_HOST_PARAM + EC_HOST_PARAM_SIZE - 1);
+		fprintf(stderr,
+			"Very likely this board doesn't have a Chromium EC.\n");
+		return -4;
+	}
 
-	for (c = 0; c < EC_MEMMAP_TEXT_MAX; c++) {
-		buf[c] = inb(EC_LPC_ADDR_MEMMAP + offset + c);
-		if (buf[c] == 0)
-			return c;
+	/*
+	 * Test if LPC command args are supported.
+	 *
+	 * The cheapest way to do this is by looking for the memory-mapped
+	 * flag.  This is faster than sending a new-style 'hello' command and
+	 * seeing whether the EC sets the EC_HOST_ARGS_FLAG_FROM_HOST flag
+	 * in args when it responds.
+	 */
+	if (inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID) != 'E' ||
+	    inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_ID + 1) != 'C' ||
+	    !(inb(EC_LPC_ADDR_MEMMAP + EC_MEMMAP_HOST_CMD_FLAGS) &
+	      EC_HOST_CMD_FLAG_LPC_ARGS_SUPPORTED)) {
+		fprintf(stderr, "EC doesn't support command args.\n");
+		return -5;
 	}
 
-	buf[EC_MEMMAP_TEXT_MAX - 1] = 0;
-	return EC_MEMMAP_TEXT_MAX - 1;
+	/* Okay, this works */
+	ec_command = ec_command_lpc;
+	ec_readmem = ec_readmem_lpc;
+	return 0;
 }