[continue tests from thread *Re: [PATCH v4 5/6] i2c: smbus: Support DDR5
SPD EEPROMs* [1] here]
[Cc: +Jean Delvare]
Dear Guenter,
Am 18.06.24 um 21:53 schrieb Guenter Roeck:
regmap write operations on i801 controllers were observed to fail with
-ENXIO errors. It appears that the i801 controller and/or at least some
spd5118 compatible chips do not support the I2C_FUNC_SMBUS_I2C_BLOCK
operation used by the regmap-i2c core if I2C_FUNC_SMBUS_I2C_BLOCK is
supported by the I2C/SMBus controller.
Stop using the regmap-i2c core and always use basic SMBus operations
instead.
Reported-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx>
Closes: https://lore.kernel.org/linux-hwmon/33f369c1-1098-458e-9398-30037bd8c5aa@xxxxxxxxxxxxx/
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
v2: Added patch
drivers/hwmon/Kconfig | 2 +-
drivers/hwmon/spd5118.c | 28 +++++++++++++++++++++++++++-
2 files changed, 28 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index d5eced417fc3..fdfa778a965d 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2184,7 +2184,7 @@ config SENSORS_INA3221
config SENSORS_SPD5118
tristate "SPD5118 Compliant Temperature Sensors"
depends on I2C
- select REGMAP_I2C
+ select REGMAP
help
If you say yes here you get support for SPD5118 (JEDEC JESD300)
compliant temperature sensors. Such sensors are found on DDR5 memory
diff --git a/drivers/hwmon/spd5118.c b/drivers/hwmon/spd5118.c
index d405c5ef755d..995c45e2a997 100644
--- a/drivers/hwmon/spd5118.c
+++ b/drivers/hwmon/spd5118.c
@@ -489,6 +489,31 @@ static bool spd5118_volatile_reg(struct device *dev, unsigned int reg)
}
}
+static int spd5118_regmap_reg_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(context, reg);
+ if (ret < 0)
+ return ret;
+
+ *val = ret;
+
+ return 0;
+}
+
+static int spd5118_regmap_reg_write(void *context, unsigned int reg,
+ unsigned int val)
+{
+ return i2c_smbus_write_byte_data(context, reg, val);
+}
+
+static const struct regmap_bus spd5118_regmap_bus = {
+ .reg_write = spd5118_regmap_reg_write,
+ .reg_read = spd5118_regmap_reg_read,
+};
+
static const struct regmap_range_cfg spd5118_regmap_range_cfg[] = {
{
.selector_reg = SPD5118_REG_I2C_LEGACY_MODE,
@@ -526,7 +551,8 @@ static int spd5118_probe(struct i2c_client *client)
if (!data)
return -ENOMEM;
- regmap = devm_regmap_init_i2c(client, &spd5118_regmap_config);
+ regmap = devm_regmap_init(dev, &spd5118_regmap_bus, client,
+ &spd5118_regmap_config);
if (IS_ERR(regmap))
return dev_err_probe(dev, PTR_ERR(regmap), "regmap init failed\n");
Unfortunately, it still fails:
$ git log --no-decorate --oneline -4
7ddcff2d44ae3 hwmon: (spd5118) Add support for Renesas/ITD SPD5118
hub controllers
e89136743324f hwmon: (spd5118) Use spd5118 specific read/write
operations
0fcc7279f0cc4 hwmon: (spd5118) Use regmap to implement paging
801b6aad6fa7a hwmon: (spd5118) Add configuration option for
auto-detection
$ uname -r
6.10.0-rc4.mx64.461-00050-g7ddcff2d44ae
$ sudo bash -c 'echo 56000 > /sys/class/hwmon/hwmon3/temp1_max'
bash: line 1: echo: write error: No such device or address
Kind regards,
Paul
[1]:
https://lore.kernel.org/all/342dae24-56c5-4b81-9591-dc23ddbb2806@xxxxxxxxxxxx/
