diff options
Diffstat (limited to 'arch/arm/mach-sa1100/ssp.c')
| -rw-r--r-- | arch/arm/mach-sa1100/ssp.c | 46 |
1 files changed, 38 insertions, 8 deletions
diff --git a/arch/arm/mach-sa1100/ssp.c b/arch/arm/mach-sa1100/ssp.c index 1604dadf27f..5eba5fbbb56 100644 --- a/arch/arm/mach-sa1100/ssp.c +++ b/arch/arm/mach-sa1100/ssp.c @@ -23,6 +23,8 @@ #include <asm/hardware.h> #include <asm/hardware/ssp.h> +#define TIMEOUT 100000 + static irqreturn_t ssp_interrupt(int irq, void *dev_id, struct pt_regs *regs) { unsigned int status = Ser4SSSR; @@ -47,18 +49,27 @@ static irqreturn_t ssp_interrupt(int irq, void *dev_id, struct pt_regs *regs) * The caller is expected to perform the necessary locking. * * Returns: - * %-ETIMEDOUT timeout occurred (for future) + * %-ETIMEDOUT timeout occurred * 0 success */ int ssp_write_word(u16 data) { - while (!(Ser4SSSR & SSSR_TNF)) + int timeout = TIMEOUT; + + while (!(Ser4SSSR & SSSR_TNF)) { + if (!--timeout) + return -ETIMEDOUT; cpu_relax(); + } Ser4SSDR = data; - while (!(Ser4SSSR & SSSR_BSY)) + timeout = TIMEOUT; + while (!(Ser4SSSR & SSSR_BSY)) { + if (!--timeout) + return -ETIMEDOUT; cpu_relax(); + } return 0; } @@ -75,15 +86,22 @@ int ssp_write_word(u16 data) * The caller is expected to perform the necessary locking. * * Returns: - * %-ETIMEDOUT timeout occurred (for future) + * %-ETIMEDOUT timeout occurred * 16-bit data success */ -int ssp_read_word(void) +int ssp_read_word(u16 *data) { - while (!(Ser4SSSR & SSSR_RNE)) + int timeout = TIMEOUT; + + while (!(Ser4SSSR & SSSR_RNE)) { + if (!--timeout) + return -ETIMEDOUT; cpu_relax(); + } + + *data = (u16)Ser4SSDR; - return Ser4SSDR; + return 0; } /** @@ -93,14 +111,26 @@ int ssp_read_word(void) * is empty. * * The caller is expected to perform the necessary locking. + * + * Returns: + * %-ETIMEDOUT timeout occurred + * 0 success */ -void ssp_flush(void) +int ssp_flush(void) { + int timeout = TIMEOUT * 2; + do { while (Ser4SSSR & SSSR_RNE) { + if (!--timeout) + return -ETIMEDOUT; (void) Ser4SSDR; } + if (!--timeout) + return -ETIMEDOUT; } while (Ser4SSSR & SSSR_BSY); + + return 0; } /** |