Introduce I3C support by defining I3C accessors for regmap and
implementing an I3C driver. Enable I3C for the NXP P3T1755.
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Two things I would like to discuss:
- Shall we reuse i2c_device_id's to get a proper name for the chip?
Looks strange, but adding all the info again for I3C looks strange as
well
- are there some suitable kernel helpers for dealing with big/little
endianess in lm75_i3c_regmap_bus? Note: I also tried to use the
non-*_reg callbacks for the regmap bus. But the constified
void-pointers make it ugly as we need to change buffers because some
registers are big endian and some little endian.
drivers/hwmon/Kconfig | 2 +
drivers/hwmon/lm75.c | 114 +++++++++++++++++++++++++++++++++++++++++-
2 files changed, 115 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index dd376602f3f1..86897b4d105f 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1412,7 +1412,9 @@ config SENSORS_LM73
config SENSORS_LM75
tristate "National Semiconductor LM75 and compatibles"
depends on I2C
+ depends on I3C || !I3C
select REGMAP_I2C
+ select REGMAP_I3C if I3C
help
If you say yes here you get support for one common type of
temperature sensor chip, with models including:
diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
index 8b4f324524da..2979f1746585 100644
--- a/drivers/hwmon/lm75.c
+++ b/drivers/hwmon/lm75.c
@@ -11,6 +11,7 @@
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
+#include <linux/i3c/device.h>
#include <linux/hwmon.h>
#include <linux/err.h>
#include <linux/of.h>
@@ -112,6 +113,8 @@ struct lm75_data {
unsigned int sample_time; /* In ms */
enum lm75_type kind;
const struct lm75_params *params;
+ u8 reg_buf[1];
+ u8 val_buf[3];
};
/*-----------------------------------------------------------------------*/
@@ -606,6 +609,77 @@ static const struct regmap_bus lm75_i2c_regmap_bus = {
.reg_write = lm75_i2c_reg_write,
};
+static int lm75_i3c_reg_read(void *context, unsigned int reg, unsigned int *val)
+{
+ struct i3c_device *i3cdev = context;
+ struct lm75_data *data = i3cdev_get_drvdata(i3cdev);
+ struct i3c_priv_xfer xfers[] = {
+ {
+ .rnw = false,
+ .len = 1,
+ .data.out = data->reg_buf,
+ },
+ {
+ .rnw = true,
+ .len = 2,
+ .data.out = data->val_buf,
+ },
+ };
+ int ret;
+
+ data->reg_buf[0] = reg;
+
+ if (reg == LM75_REG_CONF && !data->params->config_reg_16bits)
+ xfers[1].len--;
+
+ ret = i3c_device_do_priv_xfers(i3cdev, xfers, 2);
+ if (ret < 0)
+ return ret;
+
+ if (reg == LM75_REG_CONF && !data->params->config_reg_16bits)
+ *val = data->val_buf[0];
+ else if (reg == LM75_REG_CONF)
+ *val = data->val_buf[0] | (data->val_buf[1] << 8);
+ else
+ *val = data->val_buf[1] | (data->val_buf[0] << 8);
+
+ return 0;
+}
+
+static int lm75_i3c_reg_write(void *context, unsigned int reg, unsigned int val)
+{
+ struct i3c_device *i3cdev = context;
+ struct lm75_data *data = i3cdev_get_drvdata(i3cdev);
+ struct i3c_priv_xfer xfers[] = {
+ {
+ .rnw = false,
+ .len = 3,
+ .data.out = data->val_buf,
+ },
+ };
+
+ data->val_buf[0] = reg;
+
+ if (reg == PCT2075_REG_IDLE ||
+ (reg == LM75_REG_CONF && !data->params->config_reg_16bits)) {
+ xfers[0].len--;
+ data->val_buf[1] = val & 0xff;
+ } else if (reg == LM75_REG_CONF) {
+ data->val_buf[1] = val & 0xff;
+ data->val_buf[2] = (val >> 8) & 0xff;
+ } else {
+ data->val_buf[2] = val & 0xff;
+ data->val_buf[1] = (val >> 8) & 0xff;
+ }
+
+ return i3c_device_do_priv_xfers(i3cdev, xfers, 1);
+}
+
+static const struct regmap_bus lm75_i3c_regmap_bus = {
+ .reg_read = lm75_i3c_reg_read,
+ .reg_write = lm75_i3c_reg_write,
+};
+
static const struct regmap_config lm75_regmap_config = {
.reg_bits = 8,
.val_bits = 16,
@@ -750,6 +824,36 @@ static const struct i2c_device_id lm75_i2c_ids[] = {
};
MODULE_DEVICE_TABLE(i2c, lm75_i2c_ids);
+static const struct i3c_device_id lm75_i3c_ids[] = {
+ I3C_DEVICE(0x011b, 0x152a, (void *)p3t1755),
+ { /* LIST END */ }
+};
+MODULE_DEVICE_TABLE(i3c, lm75_i3c_ids);
+
+static int lm75_i3c_probe(struct i3c_device *i3cdev)
+{
+ struct device *dev = i3cdev_to_dev(i3cdev);
+ const struct i3c_device_id *id;
+ struct regmap *regmap;
+ const char *name;
+ unsigned int i;
+
+ regmap = devm_regmap_init(dev, &lm75_i3c_regmap_bus, i3cdev, &lm75_regmap_config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ id = i3c_device_match_id(i3cdev, lm75_i3c_ids);
+
+ /* Reuse i2c_device_ids is OK? Or do we want a third copy of this data in lm75_i3c_ids? */
+ for (i = 0; lm75_i2c_ids[i].name[0]; i++)
+ if ((kernel_ulong_t)id->data == lm75_i2c_ids[i].driver_data)
+ break;
+
+ name = lm75_i2c_ids[i].name[0] ? lm75_i2c_ids[i].name : "lm75compatible";
+
+ return lm75_generic_probe(dev, name, id->data, 0, regmap);
+}
+
static const struct of_device_id __maybe_unused lm75_of_match[] = {
{
.compatible = "adi,adt75",
@@ -1008,7 +1112,15 @@ static struct i2c_driver lm75_i2c_driver = {
.address_list = normal_i2c,
};
-module_i2c_driver(lm75_i2c_driver);
+static struct i3c_driver lm75_i3c_driver = {
+ .driver = {
+ .name = "lm75_i3c",
+ },
+ .probe = lm75_i3c_probe,
+ .id_table = lm75_i3c_ids,
+};
+
+module_i3c_i2c_driver(lm75_i3c_driver, &lm75_i2c_driver)
MODULE_AUTHOR("Frodo Looijaard <frodol@xxxxxx>");
MODULE_DESCRIPTION("LM75 driver");
--
2.45.2
