[PATCH AUTOSEL 3.18 16/16] i2c: scmi: Fix probe error on devices with an empty SMB0001 ACPI device node

From: Sasha Levin
Date: Wed Dec 12 2018 - 23:34:18 EST


From: Hans de Goede <hdegoede@xxxxxxxxxx>

[ Upstream commit 0544ee4b1ad574aec3b6379af5f5cdee42840971 ]

Some AMD based HP laptops have a SMB0001 ACPI device node which does not
define any methods.

This leads to the following error in dmesg:

[ 5.222731] cmi: probe of SMB0001:00 failed with error -5

This commit makes acpi_smbus_cmi_add() return -ENODEV instead in this case
silencing the error. In case of a failure of the i2c_add_adapter() call
this commit now propagates the error from that call instead of -EIO.

Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-scmi.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
index efefcfa24a4c..d2178f701b41 100644
--- a/drivers/i2c/busses/i2c-scmi.c
+++ b/drivers/i2c/busses/i2c-scmi.c
@@ -364,6 +364,7 @@ static int acpi_smbus_cmi_add(struct acpi_device *device)
{
struct acpi_smbus_cmi *smbus_cmi;
const struct acpi_device_id *id;
+ int ret;

smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
if (!smbus_cmi)
@@ -385,8 +386,10 @@ static int acpi_smbus_cmi_add(struct acpi_device *device)
acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);

- if (smbus_cmi->cap_info == 0)
+ if (smbus_cmi->cap_info == 0) {
+ ret = -ENODEV;
goto err;
+ }

snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name),
"SMBus CMI adapter %s",
@@ -397,7 +400,8 @@ static int acpi_smbus_cmi_add(struct acpi_device *device)
smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
smbus_cmi->adapter.dev.parent = &device->dev;

- if (i2c_add_adapter(&smbus_cmi->adapter)) {
+ ret = i2c_add_adapter(&smbus_cmi->adapter);
+ if (ret) {
dev_err(&device->dev, "Couldn't register adapter!\n");
goto err;
}
@@ -407,7 +411,7 @@ static int acpi_smbus_cmi_add(struct acpi_device *device)
err:
kfree(smbus_cmi);
device->driver_data = NULL;
- return -EIO;
+ return ret;
}

static int acpi_smbus_cmi_remove(struct acpi_device *device)
--
2.19.1