[PATCH v2 1/3] hw/nvram: Add a new auxiliary function to init at24c eeprom

[Yubin Zou <yubinz@google.com>]

From: Hao Wu <wuhaotsh@google.com>

In NPCM7xx boards, at24c eeproms are backed by drives. However,
these drives use unit number as unique identifier. So if we
specify two drives with the same unit number, error will occured:
`Device with id 'none85' exists`.

Instead of using i2c address as unit number, we now assign unique
unit numbers for each eeproms in each board. This avoids conflict
in providing multiple eeprom contents with the same address.

We add an auxiliary function in the at24c eeprom module for this.
This allows it to easily add at24c eeprom to non-nuvoton boards
like aspeed as well.

Change-Id: I2f056cc0507d39164335a03bc18b5c94015b4b11
Signed-off-by: Hao Wu <wuhaotsh@google.com>
---
 hw/nvram/eeprom_at24c.c         | 17 +++++++++++++++++
 include/hw/nvram/eeprom_at24c.h |  4 ++++
 2 files changed, 21 insertions(+)

diff --git a/hw/nvram/eeprom_at24c.c b/hw/nvram/eeprom_at24c.c
index 82ea97e552a15c8bcd38e38939b53545b01ad273..8542ca2b037d6e896c7b394e7ff4b6ec27297ad7 100644
--- a/hw/nvram/eeprom_at24c.c
+++ b/hw/nvram/eeprom_at24c.c
@@ -17,6 +17,7 @@
 #include "hw/qdev-properties.h"
 #include "hw/qdev-properties-system.h"
 #include "system/block-backend.h"
+#include "system/blockdev.h"
 #include "qom/object.h"
 
 /* #define DEBUG_AT24C */
@@ -264,3 +265,19 @@ static void at24c_eeprom_register(void)
 }
 
 type_init(at24c_eeprom_register)
+
+void at24c_eeprom_init_one(I2CBus *i2c_bus, int bus, uint8_t addr,
+                           uint32_t rsize, int unit_number)
+{
+    I2CSlave *i2c_dev = i2c_slave_new("at24c-eeprom", addr);
+    DeviceState *dev = DEVICE(i2c_dev);
+    BlockInterfaceType type = IF_NONE;
+    DriveInfo *dinfo;
+
+    dinfo = drive_get(type, bus, unit_number);
+    if (dinfo) {
+        qdev_prop_set_drive(dev, "drive", blk_by_legacy_dinfo(dinfo));
+    }
+    qdev_prop_set_uint32(dev, "rom-size", rsize);
+    i2c_slave_realize_and_unref(i2c_dev, i2c_bus, &error_abort);
+}
diff --git a/include/hw/nvram/eeprom_at24c.h b/include/hw/nvram/eeprom_at24c.h
index acb9857b2adddd1fe5a924652f6ebae13b674b66..fdac7c1c022f9f73307bb3ecf761caa732e999bc 100644
--- a/include/hw/nvram/eeprom_at24c.h
+++ b/include/hw/nvram/eeprom_at24c.h
@@ -36,4 +36,8 @@ I2CSlave *at24c_eeprom_init(I2CBus *bus, uint8_t address, uint32_t rom_size);
 I2CSlave *at24c_eeprom_init_rom(I2CBus *bus, uint8_t address, uint32_t rom_size,
                                 const uint8_t *init_rom, uint32_t init_rom_size);
 
+/* Init one at24c eeprom device */
+void at24c_eeprom_init_one(I2CBus *i2c_bus, int bus, uint8_t addr,
+                           uint32_t rsize, int unit_number);
+
 #endif

-- 
2.51.2.1041.gc1ab5b90ca-goog