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authorMike Isely <isely@pobox.com>2006-03-25 20:43:14 -0300
committerMauro Carvalho Chehab <mchehab@infradead.org>2006-04-02 04:55:14 -0300
commit4263fa8ca6d9f387ce0d005e861f7e945c741e6e (patch)
tree2edf536c8141f657cb976bef0003f82c2c0e8995 /drivers/media/video/cx25840/cx25840-firmware.c
parentdbcb86ed945e42e99884e7afaab2f326a2aff2ec (diff)
V4L/DVB (3639): Reduce FWSEND due to certain I2C bus adapter limits
The FWSEND parameter controls the size of the firmware chunks sent down the I2C bus to the chip. Previously this had been set to 1024 but unfortunately some I2C implementations can't transfer data in such big gulps. Specifically, the pvrusb2 driver has a hard limit of around 60 bytes, due to the encapsulation there of I2C traffic into USB messages. So we have to significantly reduce this parameter. Acked-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mike Isely <isely@pobox.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers/media/video/cx25840/cx25840-firmware.c')
-rw-r--r--drivers/media/video/cx25840/cx25840-firmware.c12
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/media/video/cx25840/cx25840-firmware.c b/drivers/media/video/cx25840/cx25840-firmware.c
index 18dd3475358..f59ced181c5 100644
--- a/drivers/media/video/cx25840/cx25840-firmware.c
+++ b/drivers/media/video/cx25840/cx25840-firmware.c
@@ -25,7 +25,17 @@
#include "cx25840-core.h"
#define FWFILE "v4l-cx25840.fw"
-#define FWSEND 1024
+
+/*
+ * Mike Isely <isely@pobox.com> - The FWSEND parameter controls the
+ * size of the firmware chunks sent down the I2C bus to the chip.
+ * Previously this had been set to 1024 but unfortunately some I2C
+ * implementations can't transfer data in such big gulps.
+ * Specifically, the pvrusb2 driver has a hard limit of around 60
+ * bytes, due to the encapsulation there of I2C traffic into USB
+ * messages. So we have to significantly reduce this parameter.
+ */
+#define FWSEND 48
#define FWDEV(x) &((x)->adapter->dev)