'struct timeval last_tv' is used to get the time of last signal change and 'struct timeval last_intr_tv' is used to get the time of last UART interrupt. 32-bit systems using 'struct timeval' will break in the year 2038, so we have to replace that code with more appropriate types. Here struct timeval is replaced with ktime_t.
Signed-off-by: Ksenija Stanojevic ksenija.stanojevic@gmail.com --- Changes in v3: - as John suggested delta function is changed to inline function, checkpatch signals a warning to change min to min_t. Is it a false positive? - change variable names.
Changes in v2: - change subject line
drivers/staging/media/lirc/lirc_sir.c | 51 +++++++++++++---------------------- 1 file changed, 18 insertions(+), 33 deletions(-)
diff --git a/drivers/staging/media/lirc/lirc_sir.c b/drivers/staging/media/lirc/lirc_sir.c index 29087f6..c98c486 100644 --- a/drivers/staging/media/lirc/lirc_sir.c +++ b/drivers/staging/media/lirc/lirc_sir.c @@ -44,7 +44,7 @@ #include <linux/ioport.h> #include <linux/kernel.h> #include <linux/serial_reg.h> -#include <linux/time.h> +#include <linux/ktime.h> #include <linux/string.h> #include <linux/types.h> #include <linux/wait.h> @@ -127,9 +127,9 @@ static int threshold = 3; static DEFINE_SPINLOCK(timer_lock); static struct timer_list timerlist; /* time of last signal change detected */ -static struct timeval last_tv = {0, 0}; +static ktime_t last; /* time of last UART data ready interrupt */ -static struct timeval last_intr_tv = {0, 0}; +static ktime_t last_intr_time; static int last_value;
static DECLARE_WAIT_QUEUE_HEAD(lirc_read_queue); @@ -400,18 +400,11 @@ static void drop_chrdev(void) }
/* SECTION: Hardware */ -static long delta(struct timeval *tv1, struct timeval *tv2) +static inline long delta(ktime_t t1, ktime_t t2) { - unsigned long deltv; - - deltv = tv2->tv_sec - tv1->tv_sec; - if (deltv > 15) - deltv = 0xFFFFFF; - else - deltv = deltv*1000000 + - tv2->tv_usec - - tv1->tv_usec; - return deltv; + /* return the delta in 32bit usecs, but cap to UINTMAX in case the + * delta is greater then 32bits */ + return (long) min((unsigned int) ktime_us_delta(t1, t2), UINT_MAX); }
static void sir_timeout(unsigned long data) @@ -432,12 +425,12 @@ static void sir_timeout(unsigned long data) /* clear unread bits in UART and restart */ outb(UART_FCR_CLEAR_RCVR, io + UART_FCR); /* determine 'virtual' pulse end: */ - pulse_end = delta(&last_tv, &last_intr_tv); + pulse_end = delta(last, last_intr_time); dev_dbg(driver.dev, "timeout add %d for %lu usec\n", last_value, pulse_end); add_read_queue(last_value, pulse_end); last_value = 0; - last_tv = last_intr_tv; + last = last_intr_time; } spin_unlock_irqrestore(&timer_lock, flags); } @@ -445,7 +438,7 @@ static void sir_timeout(unsigned long data) static irqreturn_t sir_interrupt(int irq, void *dev_id) { unsigned char data; - struct timeval curr_tv; + ktime_t curr_time; static unsigned long deltv; unsigned long deltintrtv; unsigned long flags; @@ -471,9 +464,9 @@ static irqreturn_t sir_interrupt(int irq, void *dev_id) do { del_timer(&timerlist); data = inb(io + UART_RX); - do_gettimeofday(&curr_tv); - deltv = delta(&last_tv, &curr_tv); - deltintrtv = delta(&last_intr_tv, &curr_tv); + curr_time = ktime_get(); + deltv = delta(last, curr_time); + deltintrtv = delta(last_intr_time, curr_time); dev_dbg(driver.dev, "t %lu, d %d\n", deltintrtv, (int)data); /* @@ -488,10 +481,7 @@ static irqreturn_t sir_interrupt(int irq, void *dev_id) deltv - deltintrtv); last_value = 0; - last_tv.tv_sec = - last_intr_tv.tv_sec; - last_tv.tv_usec = - last_intr_tv.tv_usec; + last = last_intr_time; deltv = deltintrtv; } } @@ -504,16 +494,11 @@ static irqreturn_t sir_interrupt(int irq, void *dev_id) add_read_queue(last_value, deltv-TIME_CONST); last_value = data; - last_tv = curr_tv; - if (last_tv.tv_usec >= TIME_CONST) { - last_tv.tv_usec -= TIME_CONST; - } else { - last_tv.tv_sec--; - last_tv.tv_usec += 1000000 - - TIME_CONST; - } + last = curr_time; + last = ktime_sub_us(last, + TIME_CONST); } - last_intr_tv = curr_tv; + last_intr_time = curr_time; if (data) { /* * start timer for end of