On 5/30/24 13:20, Thomas Weißschuh wrote:
On 2024-05-29 13:52:03+0000, Guenter Roeck wrote:
Add support for SPD5118 (Jedec JESD300-5B.01) compliant temperature
sensors. Such sensors are typically found on DDR5 memory modules.
I can get the module to automatically probe with this change:
diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index 97f338b123b1..8d9218f755d7 100644
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -382,6 +386,10 @@ 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",
(Credits go to Paul Menzel [0])
Maybe you can add that to your series.
That is specifically for SPD (eeprom) support, which I didn't provide
in the driver. It does not register the equivalent jc42.4 temperature
sensor either. Given that, using the code to register a temperature
sensor seems inappropriate.
I didn't include accessing the SPD eeprom to the driver because I don't
have a use case. I don't mind adding it, though, if others think that it is
important.
To also work with my PIIX4 I2C bus, I also need:
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index fe6e8a1bb607..ff66e883b348 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -195,6 +195,7 @@ config I2C_ISMT
config I2C_PIIX4
tristate "Intel PIIX4 and compatible (ATI/AMD/Serverworks/Broadcom/SMSC)"
depends on PCI && HAS_IOPORT
+ select I2C_SMBUS
help
If you say yes to this option, support will be included for the Intel
PIIX4 family of mainboard I2C interfaces. Specifically, the following
diff --git a/drivers/i2c/busses/i2c-piix4.c b/drivers/i2c/busses/i2c-piix4.c
index 6a0392172b2f..f8d81f8c0cb3 100644
--- a/drivers/i2c/busses/i2c-piix4.c
+++ b/drivers/i2c/busses/i2c-piix4.c
@@ -29,6 +29,7 @@
#include <linux/stddef.h>
#include <linux/ioport.h>
#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
#include <linux/slab.h>
#include <linux/dmi.h>
#include <linux/acpi.h>
@@ -982,6 +983,8 @@ static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
return retval;
}
+ i2c_register_spd(adap);
+
*padap = adap;
return 0;
}
Though I guess it's not the right place to call i2c_register_sdp(),
I'll look at it some more and then submit it.
Hmm, I didn't find a better place though.
Please copy me when you submit a patch; I can test it on an AMD system with
DDR4.
Thanks,
Guenter
