1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/tpm/tis_i2c.c b/drivers/tpm/tis_i2c.c
new file mode 100644
index 0000000..e818fba
--- /dev/null
+++ b/drivers/tpm/tis_i2c.c
@@ -0,0 +1,181 @@
+/*
+ * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <config.h>
+#include <common.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include "slb9635_i2c/tpm.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* TPM configuration */
+struct tpm {
+	int i2c_bus;
+	int slave_addr;
+	char inited;
+	int old_bus;
+} tpm;
+
+
+static int tpm_select(void)
+{
+	int ret;
+
+	tpm.old_bus = i2c_get_bus_num();
+	if (tpm.old_bus != tpm.i2c_bus) {
+		ret = i2c_set_bus_num(tpm.i2c_bus);
+		if (ret) {
+			debug("%s: Fail to set i2c bus %d\n", __func__,
+			      tpm.i2c_bus);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static int tpm_deselect(void)
+{
+	int ret;
+
+	if (tpm.old_bus != i2c_get_bus_num()) {
+		ret = i2c_set_bus_num(tpm.old_bus);
+		if (ret) {
+			debug("%s: Fail to restore i2c bus %d\n",
+			      __func__, tpm.old_bus);
+			return -1;
+		}
+	}
+	tpm.old_bus = -1;
+	return 0;
+}
+
+/**
+ * Decode TPM configuration.
+ *
+ * @param dev	Returns a configuration of TPM device
+ * @return 0 if ok, -1 on error
+ */
+static int tpm_decode_config(struct tpm *dev)
+{
+#ifdef CONFIG_OF_CONTROL
+	const void *blob = gd->fdt_blob;
+	int node, parent;
+	int i2c_bus;
+
+	node = fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM);
+	if (node < 0) {
+		debug("%s: Node not found\n", __func__);
+		return -1;
+	}
+	parent = fdt_parent_offset(blob, node);
+	if (parent < 0) {
+		debug("%s: Cannot find node parent\n", __func__);
+		return -1;
+	}
+	i2c_bus = i2c_get_bus_num_fdt(parent);
+	if (i2c_bus < 0)
+		return -1;
+	dev->i2c_bus = i2c_bus;
+	dev->slave_addr = fdtdec_get_addr(blob, node, "reg");
+#else
+	dev->i2c_bus = CONFIG_INFINEON_TPM_I2C_BUS;
+	dev->slave_addr = CONFIG_INFINEON_TPM_I2C_ADDR;
+#endif
+	return 0;
+}
+
+int tis_init(void)
+{
+	if (tpm.inited)
+		return 0;
+
+	if (tpm_decode_config(&tpm))
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	/*
+	 * Probe TPM twice; the first probing might fail because TPM is asleep,
+	 * and the probing can wake up TPM.
+	 */
+	if (i2c_probe(tpm.slave_addr) && i2c_probe(tpm.slave_addr)) {
+		debug("%s: fail to probe i2c addr 0x%x\n", __func__,
+		      tpm.slave_addr);
+		return -1;
+	}
+
+	tpm_deselect();
+
+	tpm.inited = 1;
+
+	return 0;
+}
+
+int tis_open(void)
+{
+	int rc;
+
+	if (!tpm.inited)
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	rc = tpm_open(tpm.slave_addr);
+
+	tpm_deselect();
+
+	return rc;
+}
+
+int tis_close(void)
+{
+	if (!tpm.inited)
+		return -1;
+
+	if (tpm_select())
+		return -1;
+
+	tpm_close();
+
+	tpm_deselect();
+
+	return 0;
+}
+
+int tis_sendrecv(const uint8_t *sendbuf, size_t sbuf_size,
+		uint8_t *recvbuf, size_t *rbuf_len)
+{
+	int len;
+	uint8_t buf[4096];
+
+	if (!tpm.inited)
+		return -1;
+
+	if (sizeof(buf) < sbuf_size)
+		return -1;
+
+	memcpy(buf, sendbuf, sbuf_size);
+
+	if (tpm_select())
+		return -1;
+
+	len = tpm_transmit(buf, sbuf_size);
+
+	tpm_deselect();
+
+	if (len < 10) {
+		*rbuf_len = 0;
+		return -1;
+	}
+
+	memcpy(recvbuf, buf, len);
+	*rbuf_len = len;
+
+	return 0;
+}