diff options
| author | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2013-12-27 00:28:57 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2014-01-10 06:06:20 -0200 |
| commit | 5022a2088687baeda87b03889d0791b1b908266b (patch) | |
| tree | 82c9f3366c55aee1bd5e29b88c84d2132489199e /drivers/media | |
| parent | 2276bf70a7433c2afec541257eab28a43ed6c9cf (diff) | |
[media] em28xx: properly implement AC97 wait code
Instead of assuming that msleep() is precise, use a jiffies
based code to wait for AC97 to be available.
Reviewed-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/usb/em28xx/em28xx-core.c | 7 | ||||
| -rw-r--r-- | drivers/media/usb/em28xx/em28xx.h | 3 |
2 files changed, 8 insertions, 2 deletions
diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c index b5f49703f7c..b6dc3327c51 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> @@ -252,16 +253,18 @@ 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(EM28XX_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 b792f2225ab..b0aa8497c1a 100644 --- a/drivers/media/usb/em28xx/em28xx.h +++ b/drivers/media/usb/em28xx/em28xx.h @@ -186,6 +186,9 @@ /* time in msecs to wait for i2c writes to finish */ #define EM2800_I2C_XFER_TIMEOUT 20 +/* time in msecs to wait for AC97 xfers to finish */ +#define EM28XX_AC97_XFER_TIMEOUT 100 + /* max. number of button state polling addresses */ #define EM28XX_NUM_BUTTON_ADDRESSES_MAX 5 |