From: Haibo Chen <haibo.chen@xxxxxxx>
Add chip ID check in probe function. Add this to avoid the
continuously polling error log when this device is not connect
on the i2c bus.
Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
---
drivers/input/misc/mma8450.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c
index 1b5a5e19230a..c9f7e2ee7c91 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)
{
@@ -150,7 +152,23 @@ static int mma8450_probe(struct i2c_client *c,
const struct i2c_device_id *id)
{
struct input_dev *input;
- int err;
+ int err, client_id;
+ struct i2c_adapter *adapter = NULL;
+
+ adapter = to_i2c_adapter(c->dev.parent);
+ err = i2c_check_functionality(adapter,
+ I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA);
+ if (!err)
+ return err;
+
+ client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
+ if (MMA8450_ID != client_id) {
+ dev_err(&c->dev,
+ "read chip ID 0x%x is not equal to 0x%x!\n", client_id,
+ MMA8450_ID);
+ return -EINVAL;
+ }
input = devm_input_allocate_device(&c->dev);
if (!input)
--
2.25.1
