From: Mike Frysinger <vapier-aBrp7R+bbdUdnm+yROfE0A@public.gmane.org>
To: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Ben Dooks <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>
Cc: uclinux-dist-devel-ZG0+EudsQA8dtHy/vicBwGD2FQJk+8+b@public.gmane.org,
Sonic Zhang <sonic.zhang-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>
Subject: [PATCH 2/4] i2c-bfin-twi: stop receive operation after last byte rx interrupt
Date: Wed, 25 May 2011 16:26:36 -0400 [thread overview]
Message-ID: <1306355198-18530-2-git-send-email-vapier@gentoo.org> (raw)
In-Reply-To: <1306355198-18530-1-git-send-email-vapier-aBrp7R+bbdUdnm+yROfE0A@public.gmane.org>
From: Sonic Zhang <sonic.zhang-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>
Once the last byte has been received, we can then move on to further
processing of the transfer rather than delaying. This improves the
response times with long transfers.
Signed-off-by: Sonic Zhang <sonic.zhang-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>
Signed-off-by: Mike Frysinger <vapier-aBrp7R+bbdUdnm+yROfE0A@public.gmane.org>
---
drivers/i2c/busses/i2c-bfin-twi.c | 41 ++++++++++++++++++++----------------
1 files changed, 23 insertions(+), 18 deletions(-)
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c
index 5ed6c2f..aaabd5d 100644
--- a/drivers/i2c/busses/i2c-bfin-twi.c
+++ b/drivers/i2c/busses/i2c-bfin-twi.c
@@ -130,21 +130,25 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface,
}
iface->transPtr++;
iface->readNum--;
- } else if (iface->manual_stop) {
- /* Avoid possible bus stall -
- * Flush FIFO before issuing the STOP condition
- */
- read_RCV_DATA16(iface);
- write_MASTER_CTL(iface,
- read_MASTER_CTL(iface) | STOP);
- } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
- iface->cur_msg + 1 < iface->msg_num) {
- if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
- write_MASTER_CTL(iface,
- read_MASTER_CTL(iface) | RSTART | MDIR);
- else
+ }
+
+ if (iface->readNum == 0) {
+ if (iface->manual_stop) {
+ /* Avoid possible bus stall -
+ * Flush FIFO before issuing the STOP condition
+ */
+ read_RCV_DATA16(iface);
write_MASTER_CTL(iface,
- (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
+ read_MASTER_CTL(iface) | STOP);
+ } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
+ iface->cur_msg + 1 < iface->msg_num) {
+ if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
+ write_MASTER_CTL(iface,
+ read_MASTER_CTL(iface) | RSTART | MDIR);
+ else
+ write_MASTER_CTL(iface,
+ (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
+ }
}
}
if (twi_int_status & MERR) {
@@ -239,12 +243,13 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface,
}
}
- if (iface->pmsg[iface->cur_msg].len <= 255)
- write_MASTER_CTL(iface,
+ if (iface->pmsg[iface->cur_msg].len <= 255) {
+ write_MASTER_CTL(iface,
(read_MASTER_CTL(iface) &
(~(0xff << 6))) |
- (iface->pmsg[iface->cur_msg].len << 6));
- else {
+ (iface->pmsg[iface->cur_msg].len << 6));
+ iface->manual_stop = 0;
+ } else {
write_MASTER_CTL(iface,
(read_MASTER_CTL(iface) |
(0xff << 6)));
--
1.7.5.rc3
next prev parent reply other threads:[~2011-05-25 20:26 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-25 20:26 [PATCH 1/4] i2c-bfin-twi: work around illegal i2c bus lock with long transfers Mike Frysinger
[not found] ` <1306355198-18530-1-git-send-email-vapier-aBrp7R+bbdUdnm+yROfE0A@public.gmane.org>
2011-05-25 20:26 ` Mike Frysinger [this message]
2011-05-25 20:26 ` [PATCH 3/4] i2c-bfin-twi: wake up waiting processes after transfer has finished Mike Frysinger
2011-05-25 20:26 ` [PATCH 4/4] i2c-bfin-twi: add a timeout to busbusy polling Mike Frysinger
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1306355198-18530-2-git-send-email-vapier@gentoo.org \
--to=vapier-abrp7r+bbdudnm+yrofe0a@public.gmane.org \
--cc=ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org \
--cc=linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=sonic.zhang-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org \
--cc=uclinux-dist-devel-ZG0+EudsQA8dtHy/vicBwGD2FQJk+8+b@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).