i2c: smbus: add DDR support for SPD

On my x05 laptop I got:
Memory type 0x12 not supported yet, not instantiating SPD

Adding the 0x12 case lead to a successful instantiated SPD AT24 EEPROM.
i801_smbus 0000:00:1f.3: SMBus using polling
i2c i2c-6: 2/2 memory slots populated (from DMI)
at24 6-0050: 256 byte spd EEPROM, read-only
i2c i2c-6: Successfully instantiated SPD at 0x50
at24 6-0051: 256 byte spd EEPROM, read-only

And then, I decoded it successfully via decode-dimms.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index 07c92c8495a3c895551507448e11661d8a4ee691..c85710ed954838c7ff6e949f04f6c9e2447984dc 100644 (file)
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -361,9 +361,15 @@ void i2c_register_spd(struct i2c_adapter *adap)
                return;
        }
 
+       /*
+        * Memory types could be found at section 7.18.2 (Memory Device — Type), table 78
+        * https://www.dmtf.org/sites/default/files/standards/documents/DSP0134_3.6.0.pdf
+        */
        switch (common_mem_type) {
+       case 0x12:      /* DDR */
        case 0x13:      /* DDR2 */
        case 0x18:      /* DDR3 */
+       case 0x1B:      /* LPDDR */
        case 0x1C:      /* LPDDR2 */
        case 0x1D:      /* LPDDR3 */
                name = "spd";