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media: em28xx: Bulk transfer implementation fix

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Set appropriate bulk/ISOC transfer multiplier on capture start.
This sets ISOC transfer to USB endpoint configuration
This sets bulk transfer to 48128 bytes (188 * 256)

The bulk multiplier is maximum allowed according to Empia.

Signed-off-by: Brad Love <brad@nextdimension.cc>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Brad Love 2018-02-01 17:04:37 -05:00 committed by Mauro Carvalho Chehab
parent 0eeb232f5a
commit 1b5f69f5b9
1 changed files with 13 additions and 0 deletions
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13
drivers/media/usb/em28xx/em28xx-core.c
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@ -638,6 +638,19 @@ int em28xx_capture_start(struct em28xx *dev, int start)
dev->chip_id == CHIP_ID_EM28174 ||
dev->chip_id == CHIP_ID_EM28178) {
/* The Transport Stream Enable Register moved in em2874 */
if (dev->dvb_xfer_bulk) {
/* Max Tx Size = 188 * 256 = 48128 - LCM(188,512) * 2 */
em28xx_write_reg(dev, (dev->ts == PRIMARY_TS) ?
EM2874_R5D_TS1_PKT_SIZE :
EM2874_R5E_TS2_PKT_SIZE,
0xFF);
} else {
/* ISOC Maximum Transfer Size = 188 * 5 */
em28xx_write_reg(dev, (dev->ts == PRIMARY_TS) ?
EM2874_R5D_TS1_PKT_SIZE :
EM2874_R5E_TS2_PKT_SIZE,
dev->dvb_max_pkt_size_isoc / 188);
}
if (dev->ts == PRIMARY_TS)
rc = em28xx_write_reg_bits(dev,
EM2874_R5F_TS_ENABLE,