aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/Kconfig3
-rw-r--r--drivers/i2c/busses/i2c-icy.c57
2 files changed, 60 insertions, 0 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 8b97ba4a2c0c..ee7f415a625a 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1320,6 +1320,9 @@ config I2C_ICY
This support is also available as a module. If so, the module
will be called i2c-icy.
+ If you have a 2019 edition board with an LTC2990 sensor at address
+ 0x4c, loading the module 'ltc2990' is sufficient to enable it.
+
config I2C_MLXCPLD
tristate "Mellanox I2C driver"
depends on X86_64
diff --git a/drivers/i2c/busses/i2c-icy.c b/drivers/i2c/busses/i2c-icy.c
index 0d61936dfc0b..8382eb64b424 100644
--- a/drivers/i2c/busses/i2c-icy.c
+++ b/drivers/i2c/busses/i2c-icy.c
@@ -53,6 +53,8 @@ struct icy_i2c {
void __iomem *reg_s0;
void __iomem *reg_s1;
+ struct fwnode_handle *ltc2990_fwnode;
+ struct i2c_client *ltc2990_client;
};
/*
@@ -94,11 +96,34 @@ static void icy_pcf_waitforpin(void *data)
/*
* Main i2c-icy part
*/
+static unsigned short const icy_ltc2990_addresses[] = {
+ 0x4c, 0x4d, 0x4e, 0x4f, I2C_CLIENT_END
+};
+
+/*
+ * Additional sensors exposed once this property is applied:
+ *
+ * in1 will be the voltage of the 5V rail, divided by 2.
+ * in2 will be the voltage of the 12V rail, divided by 4.
+ * temp3 will be measured using a PCB loop next the chip.
+ */
+static const u32 icy_ltc2990_meas_mode[] = {0, 3};
+
+static const struct property_entry icy_ltc2990_props[] = {
+ PROPERTY_ENTRY_U32_ARRAY("lltc,meas-mode", icy_ltc2990_meas_mode),
+ { }
+};
+
static int icy_probe(struct zorro_dev *z,
const struct zorro_device_id *ent)
{
struct icy_i2c *i2c;
struct i2c_algo_pcf_data *algo_data;
+ struct fwnode_handle *new_fwnode;
+ struct i2c_board_info ltc2990_info = {
+ .type = "ltc2990",
+ .addr = 0x4c,
+ };
i2c = devm_kzalloc(&z->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
@@ -140,6 +165,35 @@ static int icy_probe(struct zorro_dev *z,
dev_info(&z->dev, "ICY I2C controller at %pa, IRQ not implemented\n",
&z->resource.start);
+ /*
+ * The 2019 a1k.org PCBs have an LTC2990 at 0x4c, so start
+ * it automatically once ltc2990 is modprobed.
+ *
+ * in0 is the voltage of the internal 5V power supply.
+ * temp1 is the temperature inside the chip.
+ *
+ * See property_entry above for in1, in2, temp3.
+ */
+ new_fwnode = fwnode_create_software_node(icy_ltc2990_props, NULL);
+ if (IS_ERR(new_fwnode)) {
+ dev_info(&z->dev, "Failed to create fwnode for LTC2990, error: %ld\n",
+ PTR_ERR(new_fwnode));
+ } else {
+ /*
+ * Store the fwnode so we can destroy it on .remove().
+ * Only store it on success, as fwnode_remove_software_node()
+ * is NULL safe, but not PTR_ERR safe.
+ */
+ i2c->ltc2990_fwnode = new_fwnode;
+ ltc2990_info.fwnode = new_fwnode;
+
+ i2c->ltc2990_client =
+ i2c_new_probed_device(&i2c->adapter,
+ &ltc2990_info,
+ icy_ltc2990_addresses,
+ NULL);
+ }
+
return 0;
}
@@ -147,6 +201,9 @@ static void icy_remove(struct zorro_dev *z)
{
struct icy_i2c *i2c = dev_get_drvdata(&z->dev);
+ i2c_unregister_device(i2c->ltc2990_client);
+ fwnode_remove_software_node(i2c->ltc2990_fwnode);
+
i2c_del_adapter(&i2c->adapter);
}