diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h index b0aa8497c1a9932cbc78cc231d26e97e776f30bc..efdf3864276885cdd8573aba8536227eadd52b9f 100644 --- a/drivers/media/usb/em28xx/em28xx.h +++ b/drivers/media/usb/em28xx/em28xx.h @@ -183,8 +183,21 @@ #define EM28XX_INTERLACED_DEFAULT 1 -/* time in msecs to wait for i2c writes to finish */ -#define EM2800_I2C_XFER_TIMEOUT 20 +/* + * Time in msecs to wait for i2c xfers to finish. + * 35ms is the maximum time a SMBUS device could wait when + * clock stretching is used. As the transfer itself will take + * some time to happen, set it to 35 ms. + * + * Ok, I2C doesn't specify any limit. So, eventually, we may need + * to increase this timeout. + * + * FIXME: this assumes that an I2C message is not longer than 1ms. + * This is actually dependent on the I2C bus speed, although most + * devices use a 100kHz clock. So, this assumtion is true most of + * the time. + */ +#define EM28XX_I2C_XFER_TIMEOUT 36 /* time in msecs to wait for AC97 xfers to finish */ #define EM28XX_AC97_XFER_TIMEOUT 100