'struct timeval tv' and 'struct timeval now' is used to calculate the elapsed time. 'LIRC_SFH506_DELAY' is a delay t_phl in usecs.
32-bit systems using 'struct timeval' will break in the year 2038, so we have to replace that code with more appropriate types. This patch changes the lirc_parallel.c file of media: lirc driver to use ktime_t.
ktime_get() is better than using do_gettimeofday(), because it uses the monotonic clock. ktime_sub is used to subtract two ktime variables. ktime_to_us() is used to convert ktime to microsecond.
New ktime_t variable timeout, is added in lirc_off(),to improve clarity. Introduced a new ktime_t variable in lirc_lirc_irq_handler() function, to avoid the use of signal variable for storing seconds in the first part of this fucntion as later it uses a time unit that is defined by the global "timer" variable. This makes it more clear.
ktime_set() is used to set a value in seconds to a value in nanosecond so that ktime_compare() can be used appropriately. ktime_compare() is used to compare two ktime values. ktime_add_ns() is used to increment a ktime value by 1 sec.
One comment is also shifted a line up, as it was creating a 80 character warning.
Build tested it. Also tested it with sparse.
Signed-off-by: Tapasweni Pathak tapaswenipathak@gmail.com Reviewed-by: Arnd Bergmann arnd@arndb.de Signed-off-by: Arnd Bergmann arnd@arndb.de
diff --git a/drivers/staging/media/lirc/lirc_parallel.c b/drivers/staging/media/lirc/lirc_parallel.c index c1408342b1d0..c7987c01d9e0 100644 --- a/drivers/staging/media/lirc/lirc_parallel.c +++ b/drivers/staging/media/lirc/lirc_parallel.c @@ -33,7 +33,7 @@ #include <linux/fs.h> #include <linux/kernel.h> #include <linux/ioport.h> -#include <linux/time.h> +#include <linux/ktime.h> #include <linux/mm.h> #include <linux/delay.h>
@@ -144,25 +144,22 @@ static void lirc_off(void)
static unsigned int init_lirc_timer(void) { - struct timeval tv, now; + ktime_t kt, now, timeout; unsigned int level, newlevel, timeelapsed, newtimer; int count = 0;
- do_gettimeofday(&tv); - tv.tv_sec++; /* wait max. 1 sec. */ + kt = ktime_get(); + /* wait max. 1 sec. */ + timeout = ktime_add_ns(kt, NSEC_PER_SEC); level = lirc_get_timer(); do { newlevel = lirc_get_timer(); if (level == 0 && newlevel != 0) count++; level = newlevel; - do_gettimeofday(&now); - } while (count < 1000 && (now.tv_sec < tv.tv_sec - || (now.tv_sec == tv.tv_sec - && now.tv_usec < tv.tv_usec))); - - timeelapsed = (now.tv_sec + 1 - tv.tv_sec)*1000000 - + (now.tv_usec - tv.tv_usec); + now = ktime_get(); + } while (count < 1000 && (ktime_before(now, timeout))); + timeelapsed = ktime_us_delta(now, kt); if (count >= 1000 && timeelapsed > 0) { if (default_timer == 0) { /* autodetect timer */ @@ -220,8 +217,8 @@ static void rbuf_write(int signal)
static void lirc_lirc_irq_handler(void *blah) { - struct timeval tv; - static struct timeval lasttv; + ktime_t kt, delkt; + static ktime_t lastkt; static int init; long signal; int data; @@ -244,16 +241,14 @@ static void lirc_lirc_irq_handler(void *blah)
#ifdef LIRC_TIMER if (init) { - do_gettimeofday(&tv); + kt = ktime_get();
- signal = tv.tv_sec - lasttv.tv_sec; - if (signal > 15) + delkt = ktime_sub(kt, lastkt); + if (ktime_compare(delkt, ktime_set(15, 0)) > 0) /* really long time */ data = PULSE_MASK; else - data = (int) (signal*1000000 + - tv.tv_usec - lasttv.tv_usec + - LIRC_SFH506_DELAY); + data = (int) (ktime_to_us(delkt) + LIRC_SFH506_DELAY);
rbuf_write(data); /* space */ } else { @@ -301,7 +296,7 @@ static void lirc_lirc_irq_handler(void *blah) data = 1; rbuf_write(PULSE_BIT|data); /* pulse */ } - do_gettimeofday(&lasttv); + lastkt = ktime_get(); #else /* add your code here */ #endif