[U-Boot] [PATCH 1/2] spi: fix mxc_spi_slave structure allocation to clear memory
Use calloc() instead of malloc() to allocate the mxc_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot. Tested on Efika MX over several years..
Signed-off-by: Matt Sealey matt@genesi-usa.com --- drivers/spi/mxc_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index 2e15318..d1dab18 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -408,7 +408,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, if (bus >= ARRAY_SIZE(spi_bases)) return NULL;
- mxcs = malloc(sizeof(struct mxc_spi_slave)); + mxcs = calloc(sizeof(struct mxc_spi_slave), 1); if (!mxcs) { puts("mxc_spi: SPI Slave not allocated !\n"); return NULL;
Use calloc() instead of malloc() to allocate the mxs_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot.
Signed-off-by: Matt Sealey matt@genesi-usa.com --- drivers/spi/mxs_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index a037c13..5fa7f2b 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -91,7 +91,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, return NULL; }
- mxs_slave = malloc(sizeof(struct mxs_spi_slave)); + mxs_slave = calloc(sizeof(struct mxs_spi_slave), 1); if (!mxs_slave) return NULL;
Am 17/08/2012 20:15, schrieb Matt Sealey:
Use calloc() instead of malloc() to allocate the mxs_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot.
Signed-off-by: Matt Sealey matt@genesi-usa.com
drivers/spi/mxs_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index a037c13..5fa7f2b 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -91,7 +91,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, return NULL; }
- mxs_slave = malloc(sizeof(struct mxs_spi_slave));
- mxs_slave = calloc(sizeof(struct mxs_spi_slave), 1); if (!mxs_slave) return NULL;
Acked-by: Stefano Babic sbabic@denx.de
Best regards, Stefano Babic
On 17/08/2012 20:15, Matt Sealey wrote:
Use calloc() instead of malloc() to allocate the mxs_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot.
Signed-off-by: Matt Sealey matt@genesi-usa.com
drivers/spi/mxs_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxs_spi.c b/drivers/spi/mxs_spi.c index a037c13..5fa7f2b 100644 --- a/drivers/spi/mxs_spi.c +++ b/drivers/spi/mxs_spi.c @@ -91,7 +91,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, return NULL; }
- mxs_slave = malloc(sizeof(struct mxs_spi_slave));
- mxs_slave = calloc(sizeof(struct mxs_spi_slave), 1); if (!mxs_slave) return NULL;
Applied to u-boot-imx, thanks.
Best regards, Stefano Babic
Am 17/08/2012 20:15, schrieb Matt Sealey:
Use calloc() instead of malloc() to allocate the mxc_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot. Tested on Efika MX over several years..
Signed-off-by: Matt Sealey matt@genesi-usa.com
drivers/spi/mxc_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index 2e15318..d1dab18 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -408,7 +408,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, if (bus >= ARRAY_SIZE(spi_bases)) return NULL;
- mxcs = malloc(sizeof(struct mxc_spi_slave));
- mxcs = calloc(sizeof(struct mxc_spi_slave), 1); if (!mxcs) { puts("mxc_spi: SPI Slave not allocated !\n"); return NULL;
Agree, the structure must be zeroed.
Acked-by: Stefano Babic sbabic@denx.de
Best regards, Stefano Babic
On 17/08/2012 20:15, Matt Sealey wrote:
Use calloc() instead of malloc() to allocate the mxc_spi_slave structure. Clearing the memory is necessary since most of the time this gets done super early in boot, but on warm reboots, and when SPI probing is done long after the init stages it could actually pick up previously used memory, and things like the chipselect polarity and other data end up being filled with trash data if not explicitly set by the board files.
This solves a semi-random, almost unreproducable error whereby SPI devices act very, very strangly on boot. Tested on Efika MX over several years..
Signed-off-by: Matt Sealey matt@genesi-usa.com
drivers/spi/mxc_spi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c index 2e15318..d1dab18 100644 --- a/drivers/spi/mxc_spi.c +++ b/drivers/spi/mxc_spi.c @@ -408,7 +408,7 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, if (bus >= ARRAY_SIZE(spi_bases)) return NULL;
- mxcs = malloc(sizeof(struct mxc_spi_slave));
- mxcs = calloc(sizeof(struct mxc_spi_slave), 1); if (!mxcs) { puts("mxc_spi: SPI Slave not allocated !\n"); return NULL;
Applied to u-boot-imx, thanks.
Best regards, Stefano Babic
participants (3)
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Matt Sealey -
Stefano Babic -
stefano babic