[PATCH] input: mma8450: Add chip id check in probe
From: haibo.chen@nxp.com
Date: 2022-02-22 06:41:05
Subsystem:
input (keyboard, mouse, joystick, touchscreen) drivers, the rest · Maintainers:
Dmitry Torokhov, Linus Torvalds
From: Haibo Chen <haibo.chen@nxp.com> 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@nxp.com> --- 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