Hello Gabriel FERNANDEZ,
The patch 062589b13991: "Input: add st-keyscan driver" from Apr 12,
2014, leads to the following static checker warning:
drivers/input/keyboard/st-keyscan.c:156 keyscan_probe()
error: potential zalloc NULL dereference: 'keypad_data->input_dev'
drivers/input/keyboard/st-keyscan.c
125 static int keyscan_probe(struct platform_device *pdev)
126 {
127 struct st_keyscan *keypad_data;
128 struct input_dev *input_dev;
129 struct resource *res;
130 int error;
131
132 if (!pdev->dev.of_node) {
133 dev_err(&pdev->dev, "no DT data present\n");
134 return -EINVAL;
135 }
136
137 keypad_data = devm_kzalloc(&pdev->dev, sizeof(*keypad_data),
138 GFP_KERNEL);
139 if (!keypad_data)
140 return -ENOMEM;
141
142 input_dev = devm_input_allocate_device(&pdev->dev);
143 if (!input_dev) {
144 dev_err(&pdev->dev, "failed to allocate the input device\n");
145 return -ENOMEM;
146 }
147
148 input_dev->name = pdev->name;
149 input_dev->phys = "keyscan-keys/input0";
150 input_dev->dev.parent = &pdev->dev;
151 input_dev->open = keyscan_open;
152 input_dev->close = keyscan_close;
153
154 input_dev->id.bustype = BUS_HOST;
155
--> 156 error = keypad_matrix_key_parse_dt(keypad_data);
^^^^^^^^^^^
This assumes we have set "keypad_data->input_dev = input_dev;" but we
don't do that until...
157 if (error)
158 return error;
159
160 error = matrix_keypad_build_keymap(NULL, NULL,
161 keypad_data->n_rows,
162 keypad_data->n_cols,
163 NULL, input_dev);
164 if (error) {
165 dev_err(&pdev->dev, "failed to build keymap\n");
166 return error;
167 }
168
169 input_set_drvdata(input_dev, keypad_data);
170
171 keypad_data->input_dev = input_dev;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
this line here. This driver has never worked and it was included almost
five years ago. Is it worth fixing?
172
173 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
174 keypad_data->base = devm_ioremap_resource(&pdev->dev, res);
175 if (IS_ERR(keypad_data->base))
176 return PTR_ERR(keypad_data->base);
177
regards,
dan carpenter
