Hello Adam Ward,
The patch 46c413d5bb23: "regulator: da9121: Add support for device
variants via devicetree" from Nov 30, 2020, leads to the following
static checker warning:
drivers/regulator/da9121-regulator.c:383 da9121_of_parse_cb()
warn: array off by one? 'da9121_matches[pdata->num_buck]'
drivers/regulator/da9121-regulator.c
348 static int da9121_of_parse_cb(struct device_node *np,
349 const struct regulator_desc *desc,
350 struct regulator_config *config)
351 {
352 struct da9121 *chip = config->driver_data;
353 struct da9121_pdata *pdata;
354 struct gpio_desc *ena_gpiod;
355
356 if (chip->pdata == NULL) {
357 pdata = devm_kzalloc(chip->dev, sizeof(*pdata), GFP_KERNEL);
358 if (!pdata)
359 return -ENOMEM;
360 } else {
361 pdata = chip->pdata;
362 }
363
364 pdata->num_buck++;
365
366 if (pdata->num_buck > variant_parameters[chip->variant_id].num_bucks) {
^^
Smatch is complaining that this sort of looks like it should be >=
instead of >. This looks true to me as well, but I'm not positive
enough to actually send a patch. :P
367 dev_err(chip->dev, "Error: excessive regulators for device\n");
368 return -ENODEV;
369 }
370
371 ena_gpiod = fwnode_gpiod_get_index(of_fwnode_handle(np), "enable", 0,
372 GPIOD_OUT_HIGH |
373 GPIOD_FLAGS_BIT_NONEXCLUSIVE,
374 "da9121-enable");
375 if (!IS_ERR(ena_gpiod))
376 config->ena_gpiod = ena_gpiod;
377
378 if (variant_parameters[chip->variant_id].num_bucks == 2) {
379 uint32_t ripple_cancel;
380 uint32_t ripple_reg;
381 int ret;
382
383 if (of_property_read_u32(da9121_matches[pdata->num_buck].of_node,
^^^^^^^^^^^^^^^
We know that .num_bucks is 2 here so if ->num_buck is == to that then
this is one element beyond the end of the array.
384 "dlg,ripple-cancel", &ripple_cancel)) {
385 if (pdata->num_buck > 1)
386 ripple_reg = DA9xxx_REG_BUCK_BUCK2_7;
387 else
388 ripple_reg = DA9121_REG_BUCK_BUCK1_7;
389
390 ret = regmap_update_bits(chip->regmap, ripple_reg,
391 DA9xxx_MASK_BUCK_BUCKx_7_CHx_RIPPLE_CANCEL,
392 ripple_cancel);
393 if (ret < 0)
regards,
dan carpenter
