[PATCH 4/4] i2c: cgbc: Add virtual storage devices on the virtual I2C bus

[Thomas Richard (congatec GmbH)]

Add support for virtual storage devices exposed by the Board Controller
on its virtual I2C bus. There are two device types: EEPROM for persistent
storage and RAM for non-persistent storage:
- Secure Data EEPROM  (64 bytes, RO): static and dynamic board info
- BIOS EEPROM         (32 bytes, RW): reserved for BIOS applications
- BC EEPROM           (32 bytes, RO): Board Controller operational params
- User EEPROM         (32 bytes, RW): user applications
- BIOS RAM            (32 bytes, RW): reserved for BIOS applications
- BC RAM               (8 bytes, RO): Board Controller operational params
- User RAM            (16 bytes, RW): user applications

Use the at24 driver with the 24c01 entry (the most generic one) for all
virtual storage devices, customizing parameters via software_node
properties (size, pagesize, read-only flag, label).

Signed-off-by: Thomas Richard (congatec GmbH) <thomas.richard@xxxxxxxxxxx>
---
 drivers/i2c/busses/i2c-cgbc.c | 151 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 150 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-cgbc.c b/drivers/i2c/busses/i2c-cgbc.c
index c3f1c83b105a..418de90e11bb 100644
--- a/drivers/i2c/busses/i2c-cgbc.c
+++ b/drivers/i2c/busses/i2c-cgbc.c
@@ -372,6 +372,149 @@ static const struct i2c_adapter cgbc_i2c_adapter[] = {
 	},
 };
 
+static const struct property_entry cgbc_secure_data_eeprom_props[] = {
+	PROPERTY_ENTRY_U32("size", 64),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_BOOL("read-only"),
+	PROPERTY_ENTRY_STRING("label", "cgbc-secure-data-eeprom"),
+	{ }
+};
+
+static const struct software_node cgbc_secure_data_eeprom_node = {
+	.properties = cgbc_secure_data_eeprom_props,
+};
+
+static const struct property_entry cgbc_bc_eeprom_props[] = {
+	PROPERTY_ENTRY_U32("size", 32),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_BOOL("read-only"),
+	PROPERTY_ENTRY_STRING("label", "cgbc-bc-eeprom"),
+	{ }
+};
+
+static const struct software_node cgbc_bc_eeprom_node = {
+	.properties = cgbc_bc_eeprom_props,
+};
+
+static const struct property_entry cgbc_user_eeprom_props[] = {
+	PROPERTY_ENTRY_U32("size", 32),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_STRING("label", "cgbc-user-eeprom"),
+	{ }
+};
+
+static const struct software_node cgbc_user_eeprom_node = {
+	.properties = cgbc_user_eeprom_props,
+};
+
+static const struct property_entry cgbc_bios_eeprom_props[] = {
+	PROPERTY_ENTRY_U32("size", 32),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_STRING("label", "cgbc-bios-eprom"),
+	{ }
+};
+
+static const struct software_node cgbc_bios_eeprom_node = {
+	.properties = cgbc_bios_eeprom_props,
+};
+
+static const struct property_entry cgbc_bc_ram_props[] = {
+	PROPERTY_ENTRY_U32("size", 8),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_BOOL("read-only"),
+	PROPERTY_ENTRY_STRING("label", "cgbc-bc-ram"),
+	{ }
+};
+
+static const struct software_node cgbc_bc_ram_node = {
+	.properties = cgbc_bc_ram_props,
+};
+
+static const struct property_entry cgbc_user_ram_props[] = {
+	PROPERTY_ENTRY_U32("size", 16),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_STRING("label", "cgbc-user-ram"),
+	{ }
+};
+
+static const struct software_node cgbc_user_ram_node = {
+	.properties = cgbc_user_ram_props,
+};
+
+static const struct property_entry cgbc_bios_ram_props[] = {
+	PROPERTY_ENTRY_U32("size", 32),
+	PROPERTY_ENTRY_U32("pagesize", 1),
+	PROPERTY_ENTRY_STRING("label", "cgbc-bios-ram"),
+	{ }
+};
+
+static const struct software_node cgbc_bios_ram_node = {
+	.properties = cgbc_bios_ram_props,
+};
+
+static const struct i2c_board_info cgbc_i2c_board_info[] = {
+	{
+		.type = "24c01",
+		.addr = 0x40,
+		.dev_name = "cgbc-secure-data-eeprom",
+		.swnode = &cgbc_secure_data_eeprom_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x48,
+		.dev_name = "cgbc-bc-eeprom",
+		.swnode = &cgbc_bc_eeprom_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x50,
+		.dev_name = "cgbc-user-eeprom",
+		.swnode = &cgbc_user_eeprom_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x58,
+		.dev_name = "cgbc-bios-eeprom",
+		.swnode = &cgbc_bios_eeprom_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x60,
+		.dev_name = "cgbc-bc-ram",
+		.swnode = &cgbc_bc_ram_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x68,
+		.dev_name = "cgbc-user-ram",
+		.swnode = &cgbc_user_ram_node,
+	},
+	{
+		.type = "24c01",
+		.addr = 0x70,
+		.dev_name = "cgbc-bios-ram",
+		.swnode = &cgbc_bios_ram_node,
+	}
+};
+
+static void cgbc_i2c_instantiate_devices(struct i2c_adapter *adap)
+{
+	struct i2c_algo_cgbc_data *algo_data = adap->algo_data;
+	struct i2c_client *client;
+	int i;
+
+	/* We only instantiate devices on Virtual bus */
+	if (algo_data->bus_id != CGBC_I2C_VIRTUAL_BUS_ID)
+		return;
+
+	for (i = 0; i < ARRAY_SIZE(cgbc_i2c_board_info); i++) {
+		client  = i2c_new_client_device(adap, &cgbc_i2c_board_info[i]);
+		if (IS_ERR(client))
+			dev_err(&adap->dev, "Failed to register %s\n",
+				cgbc_i2c_board_info[i].dev_name);
+	}
+}
+
 static int cgbc_i2c_probe(struct platform_device *pdev)
 {
 	struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent);
@@ -393,7 +536,13 @@ static int cgbc_i2c_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	return i2c_add_numbered_adapter(&i2c->adap);
+	ret = i2c_add_numbered_adapter(&i2c->adap);
+	if (ret)
+		return ret;
+
+	cgbc_i2c_instantiate_devices(&i2c->adap);
+
+	return ret;
 }
 
 static void cgbc_i2c_remove(struct platform_device *pdev)

-- 
2.53.0