[PATCH v5 5/6] i2c: smbus: Support DDR5 and LPDDR5 SPD EEPROMs

From: Guenter Roeck
Date: Mon Jun 10 2024 - 10:43:09 EST


Detect (LP)DDR5 memory and instantiate the SPD5118 driver automatically.

Suggested-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
Cc: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Armin Wolf <W_Armin@xxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
v5: Added reference to LPDDR5 to subject and description
Updated comments associated with i2c_register_spd()
to include support for (LP)DDR5

v4: New patch

drivers/i2c/i2c-smbus.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index 97f338b123b1..f809f0ef2004 100644
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -308,7 +308,7 @@ EXPORT_SYMBOL_GPL(i2c_free_slave_host_notify_device);
* target systems are the same.
* Restrictions to automatic SPD instantiation:
* - Only works if all filled slots have the same memory type
- * - Only works for DDR, DDR2, DDR3 and DDR4 for now
+ * - Only works for (LP)DDR memory types up to DDR5
* - Only works on systems with 1 to 8 memory slots
*/
#if IS_ENABLED(CONFIG_DMI)
@@ -382,6 +382,10 @@ void i2c_register_spd(struct i2c_adapter *adap)
case 0x1E: /* LPDDR4 */
name = "ee1004";
break;
+ case 0x22: /* DDR5 */
+ case 0x23: /* LPDDR5 */
+ name = "spd5118";
+ break;
default:
dev_info(&adap->dev,
"Memory type 0x%02x not supported yet, not instantiating SPD\n",
--
2.39.2