From: Torsten Fleischer <torfl6...@gmail.com>
The assignment of SPI_GPIO_NO_CHIPSELECT to cs_gpios[0] causes the following
compiler warning, when building for 64 bit systems:
"warning: overflow in implicit constant conversion [-Woverflow]".
This is because the SPI_GPIO_NO_CHIPSELECT flag is a '-1' type casted to
unsigned long and cs_gpios is of the type int.
Furthermore the chip select's GPIO number is locally stored as unsigned int
and compared with SPI_GPIO_NO_CHIPSELECT. Thus the result of the comparison
is always false, if unsigned long and unsigned int have a different size.
As part of the fix this patch adds a check for the device tree's cs-gpios
property.
Reported-by: kbuild test robot <fengguang...@intel.com>
Signed-off-by: Torsten Fleischer <torfl6...@gmail.com>
---
drivers/spi/spi-gpio.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index f0492c9..4b600d4 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -48,7 +48,7 @@ struct spi_gpio {
struct spi_bitbang bitbang;
struct spi_gpio_platform_data pdata;
struct platform_device *pdev;
- int cs_gpios[0];
+ unsigned long cs_gpios[0];
};
/*----------------------------------------------------------------------*/
@@ -220,7 +220,7 @@ static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device
*spi,
static void spi_gpio_chipselect(struct spi_device *spi, int is_active)
{
struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
- unsigned int cs = spi_gpio->cs_gpios[spi->chip_select];
+ unsigned long cs = spi_gpio->cs_gpios[spi->chip_select];
/* set initial clock polarity */
if (is_active)
@@ -234,7 +234,7 @@ static void spi_gpio_chipselect(struct spi_device *spi, int
is_active)
static int spi_gpio_setup(struct spi_device *spi)
{
- unsigned int cs;
+ unsigned long cs;
int status = 0;
struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
struct device_node *np = spi->master->dev.of_node;
@@ -249,7 +249,7 @@ static int spi_gpio_setup(struct spi_device *spi)
/*
* ... otherwise, take it from spi->controller_data
*/
- cs = (unsigned int)(uintptr_t) spi->controller_data;
+ cs = (uintptr_t) spi->controller_data;
}
if (!spi->controller_state) {
@@ -277,7 +277,7 @@ static int spi_gpio_setup(struct spi_device *spi)
static void spi_gpio_cleanup(struct spi_device *spi)
{
struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
- unsigned int cs = spi_gpio->cs_gpios[spi->chip_select];
+ unsigned long cs = spi_gpio->cs_gpios[spi->chip_select];
if (cs != SPI_GPIO_NO_CHIPSELECT)
gpio_free(cs);
@@ -437,7 +437,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
return status;
master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) +
- (sizeof(int) * num_devices));
+ (sizeof(unsigned long) * num_devices));
if (!master) {
status = -ENOMEM;
goto gpio_free;
@@ -470,9 +470,15 @@ static int spi_gpio_probe(struct platform_device *pdev)
if (!SPI_N_CHIPSEL)
spi_gpio->cs_gpios[0] = SPI_GPIO_NO_CHIPSELECT;
else
- for (i = 0; i < SPI_N_CHIPSEL; i++)
- spi_gpio->cs_gpios[i] =
- of_get_named_gpio(np, "cs-gpios", i);
+ for (i = 0; i < SPI_N_CHIPSEL; i++) {
+ status = of_get_named_gpio(np, "cs-gpios", i);
+ if (status < 0) {
+ dev_err(&pdev->dev,
+ "invalid cs-gpios property\n");
+ goto gpio_free;
+ }
+ spi_gpio->cs_gpios[i] = status;
+ }
}
#endif
--
1.8.4.5
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