dm: tpm: sandbox: Convert TPM driver to driver model

Convert the sandbox TPM driver to use driver model. Add it to the device
tree so that it can be found on start-up.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Heiko Schocher <hs@denx.de>

arch/sandbox/dts/sandbox.dts

@@ -156,6 +156,10 @@
 		sides = <4>;
 	};
 
+	tpm {
+		compatible = "google,sandbox-tpm";
+	};
+
 	triangle {
 		compatible = "demo-shape";
 		colour = "cyan";

configs/sandbox_defconfig

@@ -31,6 +31,7 @@ CONFIG_CROS_EC_KEYB=y
 CONFIG_LED=y
 CONFIG_LED_GPIO=y
 CONFIG_SANDBOX_SERIAL=y
+CONFIG_DM_TPM=y
 CONFIG_TPM_TIS_SANDBOX=y
 CONFIG_SYS_I2C_SANDBOX=y
 CONFIG_SANDBOX_SPI=y

drivers/tpm/tpm_tis_sandbox.c

@@ -5,6 +5,8 @@
  */
 
 #include <common.h>
+#include <dm.h>
+#include <tpm.h>
 #include <asm/state.h>
 #include <asm/unaligned.h>
 #include <linux/crc8.h>
@@ -56,7 +58,7 @@ enum {
  */
 static struct tpm_state {
 	uint8_t nvdata[NV_SEQ_COUNT][NV_DATA_SIZE];
-} state;
+} g_state;
 
 /**
  * sandbox_tpm_read_state() - read the sandbox EC state from the state file
@@ -82,7 +84,7 @@ static int sandbox_tpm_read_state(const void *blob, int node)
 		sprintf(prop_name, "nvdata%d", i);
 		prop = fdt_getprop(blob, node, prop_name, &len);
 		if (prop && len == NV_DATA_SIZE)
-			memcpy(state.nvdata[i], prop, NV_DATA_SIZE);
+			memcpy(g_state.nvdata[i], prop, NV_DATA_SIZE);
 	}
 
 	return 0;
@@ -110,7 +112,7 @@ static int sandbox_tpm_write_state(void *blob, int node)
 		char prop_name[20];
 
 		sprintf(prop_name, "nvdata%d", i);
-		fdt_setprop(blob, node, prop_name, state.nvdata[i],
+		fdt_setprop(blob, node, prop_name, g_state.nvdata[i],
 			    NV_DATA_SIZE);
 	}
 
@@ -135,10 +137,11 @@ static int index_to_seq(uint32_t index)
 	return -1;
 }
 
-int tis_sendrecv(const u8 *sendbuf, size_t send_size,
+static int sandbox_tpm_xfer(struct udevice *dev, const uint8_t *sendbuf,
-		 u8 *recvbuf, size_t *recv_len)
+			    size_t send_size, uint8_t *recvbuf,
+			    size_t *recv_len)
 {
-	struct tpm_state *tpm = &state;
+	struct tpm_state *tpm = dev_get_priv(dev);
 	uint32_t code, index, length, type;
 	uint8_t *data;
 	int seq;
@@ -241,20 +244,50 @@ int tis_sendrecv(const u8 *sendbuf, size_t send_size,
 	return 0;
 }
 
-int tis_open(void)
+static int sandbox_tpm_get_desc(struct udevice *dev, char *buf, int size)
 {
-	printf("%s\n", __func__);
+	if (size < 15)
+		return -ENOSPC;
+
+	return snprintf(buf, size, "sandbox TPM");
+}
+
+static int sandbox_tpm_probe(struct udevice *dev)
+{
+	struct tpm_state *tpm = dev_get_priv(dev);
+
+	memcpy(tpm, &g_state, sizeof(*tpm));
+
 	return 0;
 }
 
-int tis_close(void)
+static int sandbox_tpm_open(struct udevice *dev)
 {
-	printf("%s\n", __func__);
 	return 0;
 }
 
-int tis_init(void)
+static int sandbox_tpm_close(struct udevice *dev)
 {
-	printf("%s\n", __func__);
 	return 0;
 }
+
+static const struct tpm_ops sandbox_tpm_ops = {
+	.open		= sandbox_tpm_open,
+	.close		= sandbox_tpm_close,
+	.get_desc	= sandbox_tpm_get_desc,
+	.xfer		= sandbox_tpm_xfer,
+};
+
+static const struct udevice_id sandbox_tpm_ids[] = {
+	{ .compatible = "google,sandbox-tpm" },
+	{ }
+};
+
+U_BOOT_DRIVER(sandbox_tpm) = {
+	.name   = "sandbox_tpm",
+	.id     = UCLASS_TPM,
+	.of_match = sandbox_tpm_ids,
+	.ops    = &sandbox_tpm_ops,
+	.probe	= sandbox_tpm_probe,
+	.priv_auto_alloc_size = sizeof(struct tpm_state),
+};