diff options
| -rw-r--r-- | drivers/gpio/gpio-mcp23s08.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c index d7f384f9cde0..00fbb30b9b10 100644 --- a/drivers/gpio/gpio-mcp23s08.c +++ b/drivers/gpio/gpio-mcp23s08.c @@ -895,8 +895,13 @@ static int mcp23s08_probe(struct spi_device *spi) return -ENODEV; } - for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) + for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) { pullups[addr] = 0; + if (spi_present_mask & (1 << addr)) + chips++; + } + if (!chips) + return -ENODEV; } else { type = spi_get_device_id(spi)->driver_data; pdata = dev_get_platdata(&spi->dev); @@ -935,6 +940,10 @@ static int mcp23s08_probe(struct spi_device *spi) if (!(spi_present_mask & (1 << addr))) continue; chips--; + if (chips < 0) { + dev_err(&spi->dev, "FATAL: invalid negative chip id\n"); + goto fail; + } data->mcp[addr] = &data->chip[chips]; status = mcp23s08_probe_one(data->mcp[addr], &spi->dev, spi, 0x40 | (addr << 1), type, base, |