[PATCH 1/3] staging: media: lirc: Replace timeval with ktime_t in lirc_serial.c

[PATCH 1/3] staging: media: lirc: Replace timeval with ktime_t in lirc_serial.c

[Arnd Bergmann]

'struct timeval tv' is used to get current time.
'static struct timeval lasttv' is used to get last interrupt time.

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_serial.c file of media: lirc 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. The check to test time
going backwards is also removed. Intialization to static
variable is also removed. ktime_to_us() is used to convert
ktime_t to microsecond value. deltv is changed to delkt, a
ktime_t type varibale from long to assign the ktime_sub value
directly. ktime_compare is used to compare delkt with 15
seconds, which is changed to a nanosecond value by using
ktime_set().

Build tested it.

Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
These three patches were still in my backlog and part of linux-next
but never made it into mainline. Please apply to the v4l tree.

diff --git a/drivers/staging/media/lirc/lirc_serial.c b/drivers/staging/media/lirc/lirc_serial.c
index 64a7b2fc5289..b798b311d32c 100644
--- a/drivers/staging/media/lirc/lirc_serial.c
+++ b/drivers/staging/media/lirc/lirc_serial.c
@@ -59,7 +59,7 @@
 #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>
@@ -204,7 +204,7 @@ static struct lirc_serial hardware[] = {
 
 #define RBUF_LEN 256
 
-static struct timeval lasttv = {0, 0};
+static ktime_t lastkt;
 
 static struct lirc_buffer rbuf;
 
@@ -542,10 +542,10 @@ static void frbwrite(int l)
 
 static irqreturn_t lirc_irq_handler(int i, void *blah)
 {
-	struct timeval tv;
+	ktime_t kt;
 	int counter, dcd;
 	u8 status;
-	long deltv;
+	ktime_t delkt;
 	int data;
 	static int last_dcd = -1;
 
@@ -565,7 +565,7 @@ static irqreturn_t lirc_irq_handler(int i, void *blah)
 		if ((status & hardware[type].signal_pin_change)
 		    && sense != -1) {
 			/* get current time */
-			do_gettimeofday(&tv);
+			kt = ktime_get();
 
 			/* New mode, written by Trent Piepho
 			   <xyzzy@u.washington.edu>. */
@@ -594,34 +594,20 @@ static irqreturn_t lirc_irq_handler(int i, void *blah)
 			dcd = (status & hardware[type].signal_pin) ? 1 : 0;
 
 			if (dcd == last_dcd) {
-				pr_warn("ignoring spike: %d %d %lx %lx %lx %lx\n",
-					dcd, sense,
-					tv.tv_sec, lasttv.tv_sec,
-					(unsigned long)tv.tv_usec,
-					(unsigned long)lasttv.tv_usec);
+				pr_warn("ignoring spike: %d %d %llx %llx\n",
+					dcd, sense, ktime_to_us(kt),
+					ktime_to_us(lastkt));
 				continue;
 			}
 
-			deltv = tv.tv_sec-lasttv.tv_sec;
-			if (tv.tv_sec < lasttv.tv_sec ||
-			    (tv.tv_sec == lasttv.tv_sec &&
-			     tv.tv_usec < lasttv.tv_usec)) {
-				pr_warn("AIEEEE: your clock just jumped backwards\n");
-				pr_warn("%d %d %lx %lx %lx %lx\n",
-					dcd, sense,
-					tv.tv_sec, lasttv.tv_sec,
-					(unsigned long)tv.tv_usec,
-					(unsigned long)lasttv.tv_usec);
-				data = PULSE_MASK;
-			} else if (deltv > 15) {
+			delkt = ktime_sub(kt, lastkt);
+			if (ktime_compare(delkt, ktime_set(15, 0)) > 0) {
 				data = PULSE_MASK; /* really long time */
 				if (!(dcd^sense)) {
 					/* sanity check */
-					pr_warn("AIEEEE: %d %d %lx %lx %lx %lx\n",
-						dcd, sense,
-						tv.tv_sec, lasttv.tv_sec,
-						(unsigned long)tv.tv_usec,
-						(unsigned long)lasttv.tv_usec);
+					pr_warn("AIEEEE: %d %d %llx %llx\n",
+						dcd, sense, ktime_to_us(kt),
+						ktime_to_us(lastkt));
 					/*
 					 * detecting pulse while this
 					 * MUST be a space!
@@ -629,11 +615,9 @@ static irqreturn_t lirc_irq_handler(int i, void *blah)
 					sense = sense ? 0 : 1;
 				}
 			} else
-				data = (int) (deltv*1000000 +
-					       tv.tv_usec -
-					       lasttv.tv_usec);
+				data = (int) ktime_to_us(delkt);
 			frbwrite(dcd^sense ? data : (data|PULSE_BIT));
-			lasttv = tv;
+			lastkt = kt;
 			last_dcd = dcd;
 			wake_up_interruptible(&rbuf.wait_poll);
 		}
@@ -790,7 +774,7 @@ static int set_use_inc(void *data)
 	unsigned long flags;
 
 	/* initialize timestamp */
-	do_gettimeofday(&lasttv);
+	lastkt = ktime_get();
 
 	spin_lock_irqsave(&hardware[type].lock, flags);
 
@@ -979,7 +963,7 @@ static int lirc_serial_resume(struct platform_device *dev)
 
 	spin_lock_irqsave(&hardware[type].lock, flags);
 	/* Enable Interrupt */
-	do_gettimeofday(&lasttv);
+	lastkt = ktime_get();
 	soutp(UART_IER, sinp(UART_IER)|UART_IER_MSI);
 	off();
 

[PATCH 2/3] staging: media: lirc: Replace timeval with ktime_t in lirc_sasem.c

[Arnd Bergmann]

'struct timeval presstime' and 'struct timeval tv' is used to
calculate the time since the last button press.

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 media: lirc driver to use ktime_t.

ktime_get() is  better than using do_gettimeofday(), because it uses
the monotonic clock. ktime_sub() are used to subtract two ktime
variables. 'ms' is only used to check how much time has passed by comparing
to 250. So instead of using expensive ktime_to_ms() call, it has been
changed to hold nanoseconds by using ktime_to_ns().

Build tested it. Tested with sparse too.

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_sasem.c b/drivers/staging/media/lirc/lirc_sasem.c
index f2dca69c2bc0..2218d0042030 100644
--- a/drivers/staging/media/lirc/lirc_sasem.c
+++ b/drivers/staging/media/lirc/lirc_sasem.c
@@ -42,6 +42,7 @@
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/usb.h>
+#include <linux/ktime.h>
 
 #include <media/lirc.h>
 #include <media/lirc_dev.h>
@@ -111,7 +112,7 @@ struct sasem_context {
 	} tx;
 
 	/* for dealing with repeat codes (wish there was a toggle bit!) */
-	struct timeval presstime;
+	ktime_t presstime;
 	char lastcode[8];
 	int codesaved;
 };
@@ -566,8 +567,8 @@ static void incoming_packet(struct sasem_context *context,
 {
 	int len = urb->actual_length;
 	unsigned char *buf = urb->transfer_buffer;
-	long ms;
-	struct timeval tv;
+	u64 ns;
+	ktime_t kt;
 
 	if (len != 8) {
 		dev_warn(&context->dev->dev,
@@ -584,9 +585,8 @@ static void incoming_packet(struct sasem_context *context,
 	 */
 
 	/* get the time since the last button press */
-	do_gettimeofday(&tv);
-	ms = (tv.tv_sec - context->presstime.tv_sec) * 1000 +
-	     (tv.tv_usec - context->presstime.tv_usec) / 1000;
+	kt = ktime_get();
+	ns = ktime_to_ns(ktime_sub(kt, context->presstime));
 
 	if (memcmp(buf, "\x08\0\0\0\0\0\0\0", 8) == 0) {
 		/*
@@ -600,10 +600,9 @@ static void incoming_packet(struct sasem_context *context,
 		 *   in that time and then get a false repeat of the previous
 		 *   press but it is long enough for a genuine repeat
 		 */
-		if ((ms < 250) && (context->codesaved != 0)) {
+		if ((ns < 250 * NSEC_PER_MSEC) && (context->codesaved != 0)) {
 			memcpy(buf, &context->lastcode, 8);
-			context->presstime.tv_sec = tv.tv_sec;
-			context->presstime.tv_usec = tv.tv_usec;
+			context->presstime = kt;
 		}
 	} else {
 		/* save the current valid code for repeats */
@@ -613,8 +612,7 @@ static void incoming_packet(struct sasem_context *context,
 		 * just for safety reasons
 		 */
 		context->codesaved = 1;
-		context->presstime.tv_sec = tv.tv_sec;
-		context->presstime.tv_usec = tv.tv_usec;
+		context->presstime = kt;
 	}
 
 	lirc_buffer_write(context->driver->rbuf, buf);

[PATCH 3/3] staging: media: lirc: Replace timeval with ktime_t in lirc_parallel.c

[Arnd Bergmann]

'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