[PATCH 3.13 102/212] gpio: mcp23s08: Bug fix of SPI device tree registration.

Kamal Mostafa
2014-06-17T21:43:16Z

From: Michael Welling <mwelling@ieee.org>

commit 99e4b98dbe3ad1fe38a74d12c3b8d44a55930de4 upstream.

The chips variable needs to be incremented for each chip that is
found in the spi_present_mask when registering via device tree.
Without this and the checking a negative index is passed to the
data->chip array in a subsequent loop.

Signed-off-by: Michael Welling <mwelling@ieee.org>
Acked-by: Peter Korsgaard <peter@korsgaard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/gpio/gpio-mcp23s08.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpio-mcp23s08.c b/drivers/gpio/gpio-mcp23s08.c
index 2deb0c5..114e1aa 100644
--- a/drivers/gpio/gpio-mcp23s08.c
+++ b/drivers/gpio/gpio-mcp23s08.c
@@ -656,9 +656,11 @@ static int mcp23s08_probe(struct spi_device *spi)
dev_err(&spi->dev, "invalid spi-present-mask\n");
return -ENODEV;
}
-
- for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++)
+ for (addr = 0; addr < ARRAY_SIZE(pdata->chip); addr++) {
+ if ((spi_present_mask & (1 << addr)))
+ chips++;
pullups[addr] = 0;
+ }
} else {
type = spi_get_device_id(spi)->driver_data;
pdata = dev_get_platdata(&spi->dev);
@@ -681,12 +683,12 @@ static int mcp23s08_probe(struct spi_device *spi)
pullups[addr] = pdata->chip[addr].pullups;
}

- if (!chips)
- return -ENODEV;
-
base = pdata->base;
}

+ if (!chips)
+ return -ENODEV;
+
data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08),
GFP_KERNEL);
if (!data)
--
1.9.1