From: Mauro Carvalho Chehab <m.chehab@xxxxxxxxxxx>
Instead of assuming that msleep() is precise, use a jiffies
based code to wait for AC97 to be available.
Signed-off-by: Mauro Carvalho Chehab <m.chehab@xxxxxxxxxxx>
---
drivers/media/usb/em28xx/em28xx-core.c | 7 +++++--
drivers/media/usb/em28xx/em28xx.h | 5 ++++-
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c
index 818248d3fd28..36b2f1ab4474 100644
--- a/drivers/media/usb/em28xx/em28xx-core.c
+++ b/drivers/media/usb/em28xx/em28xx-core.c
@@ -23,6 +23,7 @@
*/
#include <linux/init.h>
+#include <linux/jiffies.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/slab.h>
@@ -254,16 +255,18 @@ EXPORT_SYMBOL_GPL(em28xx_toggle_reg_bits);
*/
static int em28xx_is_ac97_ready(struct em28xx *dev)
{
- int ret, i;
+ unsigned long timeout = jiffies + msecs_to_jiffies(EM2800_AC97_XFER_TIMEOUT);
+ int ret;
/* Wait up to 50 ms for AC97 command to complete */
- for (i = 0; i < 10; i++, msleep(5)) {
+ while (time_is_after_jiffies(timeout)) {
ret = em28xx_read_reg(dev, EM28XX_R43_AC97BUSY);
if (ret < 0)
return ret;
if (!(ret & 0x01))
return 0;
+ msleep (5);
}
em28xx_warn("AC97 command still being executed: not handled properly!\n");
diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h
index 9d6f43e4681f..ac79501f5d9f 100644
--- a/drivers/media/usb/em28xx/em28xx.h
+++ b/drivers/media/usb/em28xx/em28xx.h
@@ -182,9 +182,12 @@
#define EM28XX_INTERLACED_DEFAULT 1
-/* time in msecs to wait for i2c writes to finish */
+/* time in msecs to wait for i2c xfers to finish */
#define EM2800_I2C_XFER_TIMEOUT 20
+/* time in msecs to wait for AC97 xfers to finish */
+#define EM2800_AC97_XFER_TIMEOUT 100
+
/* max. number of button state polling addresses */
#define EM28XX_NUM_BUTTON_ADDRESSES_MAX 5
--
1.8.3.1
--
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