From: Luwei Zhou <b45643@xxxxxxxxxxxxx>
Prevent continuous polling error logs by adding a chip ID check in the
probe function. This ensures the driver only proceeds when the mma8450 is
present, avoiding issues in scenarios like missing add-on cards.
Signed-off-by: Luwei Zhou <b45643@xxxxxxxxxxxxx>
Signed-off-by: Fugang Duan <B38611@xxxxxxxxxxxxx>
Signed-off-by: Vipul Kumar <vipul_kumar@xxxxxxxxxx>
Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
---
change from v2 to v3
- add if (client_id < 0)
return dev_err_probe(&c->dev, client_id, "Failed to read chip ID\n");
change from v1 to v2
- Use *adapter = c->adapter
- Use if (!i2c_check_functionality())
---
drivers/input/misc/mma8450.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
index 08412239b8e69..5d1455bffbb05 100644
--- a/drivers/input/misc/mma8450.c
+++ b/drivers/input/misc/mma8450.c
@@ -38,6 +38,8 @@
#define MMA8450_CTRL_REG1 0x38
#define MMA8450_CTRL_REG2 0x39
+#define MMA8450_ID 0xc6
+#define MMA8450_WHO_AM_I 0x0f
static int mma8450_read(struct i2c_client *c, unsigned int off)
{
@@ -148,8 +150,19 @@ static void mma8450_close(struct input_dev *input)
*/
static int mma8450_probe(struct i2c_client *c)
{
+ struct i2c_adapter *adapter = c->adapter;
struct input_dev *input;
- int err;
+ int err, client_id;
+
+ if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_BYTE_DATA))
+ return dev_err_probe(&c->dev, -EINVAL, "I2C adapter can't support SMBUS BYTE");
+
+ client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
+ if (client_id < 0)
+ return dev_err_probe(&c->dev, client_id, "Failed to read chip ID\n");
+ if (client_id != MMA8450_ID)
+ return dev_err_probe(&c->dev, -EINVAL, "Read chip ID 0x%x is not equal to 0x%x!\n",
+ client_id, MMA8450_ID);
input = devm_input_allocate_device(&c->dev);
if (!input)
--
2.34.1
