[PATCH] fbdev: radeon: Remove 'struct timeval' usage

From: Tina Ruchandani
Date: Mon May 25 2015 - 00:07:26 EST


'struct timeval' uses a 32-bit representation for the
seconds field which will overflow in the year 2038 and beyond.
This patch replaces the usage of 'struct timeval' with
ktime_t which uses a 64-bit time representation and does not
suffer from the y2038 problem. This patch is part of a larger
effort to remove all instances of 'struct timeval', 'struct
timespec', time_t and other 32-bit timekeeping variables
from the kernel.
The patch also replaces the use of real time (do_gettimeofday)
with monotonic time (ktime_get).

Signed-off-by: Tina Ruchandani <ruchandani.tina@xxxxxxxxx>
---
drivers/video/fbdev/aty/radeon_base.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/drivers/video/fbdev/aty/radeon_base.c b/drivers/video/fbdev/aty/radeon_base.c
index 01237c8..9747e9e 100644
--- a/drivers/video/fbdev/aty/radeon_base.c
+++ b/drivers/video/fbdev/aty/radeon_base.c
@@ -64,6 +64,7 @@
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/time.h>
+#include <linux/ktime.h>
#include <linux/fb.h>
#include <linux/ioport.h>
#include <linux/init.h>
@@ -461,8 +462,8 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo)
int hTotal, vTotal, num, denom, m, n;
unsigned long long hz, vclk;
long xtal;
- struct timeval start_tv, stop_tv;
- long total_secs, total_usecs;
+ ktime_t start, stop;
+ s64 delta;
int i;

/* Ugh, we cut interrupts, bad bad bad, but we want some precision
@@ -478,7 +479,7 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo)
if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) == 0)
break;

- do_gettimeofday(&start_tv);
+ start = ktime_get();

for(i=0; i<1000000; i++)
if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) != 0)
@@ -487,20 +488,18 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo)
for(i=0; i<1000000; i++)
if (((INREG(CRTC_VLINE_CRNT_VLINE) >> 16) & 0x3ff) == 0)
break;
-
- do_gettimeofday(&stop_tv);
-
+
+ stop = ktime_get();
+
local_irq_enable();

- total_secs = stop_tv.tv_sec - start_tv.tv_sec;
- if (total_secs > 10)
+ delta = ktime_us_delta(stop, start);
+
+ /* Return -1 if more than 10 seconds have elapsed */
+ if (delta > (10*1000000))
return -1;
- total_usecs = stop_tv.tv_usec - start_tv.tv_usec;
- total_usecs += total_secs * 1000000;
- if (total_usecs < 0)
- total_usecs = -total_usecs;
- hz = 1000000/total_usecs;
-
+ hz = 1000000/delta;
+
hTotal = ((INREG(CRTC_H_TOTAL_DISP) & 0x1ff) + 1) * 8;
vTotal = ((INREG(CRTC_V_TOTAL_DISP) & 0x3ff) + 1);
vclk = (long long)hTotal * (long long)vTotal * hz;
@@ -548,7 +547,7 @@ static int radeon_probe_pll_params(struct radeonfb_info *rinfo)
denom *= 3;
break;
case 6:
- denom *= 6;
+ denom *= 6;
break;
case 7:
denom *= 12;
--
2.2.0.rc0.207.ga3a616c

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