From 1863f213d3e878d10589ebc0aae1c861c3b0f0c3 Mon Sep 17 00:00:00 2001 From: Luwei Zhou Date: Mon, 16 Dec 2024 10:28:51 -0800 Subject: [PATCH] Input: mma8450 - add chip ID check in probe 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 Signed-off-by: Fugang Duan Signed-off-by: Vipul Kumar Signed-off-by: Dong Aisheng Signed-off-by: Frank Li Link: https://lore.kernel.org/r/20241216173205.211058-1-Frank.Li@nxp.com Signed-off-by: Dmitry Torokhov --- drivers/input/misc/mma8450.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/drivers/input/misc/mma8450.c b/drivers/input/misc/mma8450.c index 08412239b8e6..0c661140fb88 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 +150,20 @@ 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 doesn't support SMBUS BYTE"); + + client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I); + if (client_id != MMA8450_ID) + return dev_err_probe(&c->dev, -EINVAL, + "unexpected chip ID 0x%x (vs 0x%x)\n", + client_id, MMA8450_ID); input = devm_input_allocate_device(&c->dev); if (!input) -- 2.50.1