linux-i2c.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Heiner Kallweit <hkallweit1@gmail.com>
To: Wolfram Sang <wsa@the-dreams.de>,
	Jerome Brunet <jbrunet@baylibre.com>,
	Kevin Hilman <khilman@baylibre.com>
Cc: "linux-i2c@vger.kernel.org" <linux-i2c@vger.kernel.org>,
	linux-amlogic@lists.infradead.org
Subject: [PATCH v5 08/10] i2c: meson: don't create separate token chain just for the stop command
Date: Sat, 25 Mar 2017 14:11:08 +0100	[thread overview]
Message-ID: <df09e8d9-71ae-2c7f-5a02-940e39d6de92@gmail.com> (raw)
In-Reply-To: <645519b8-93e6-57b1-ae8f-7804c6beb9b1@gmail.com>

We can directly add the stop token to the token chain including the
last transfer chunk. This is more efficient than creating a separate
token chain just for the stop command.
And it allows us to get rid of state STATE_STOP completely.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
v2:
- rebased
v3:
- no changes
v4:
- no changes
v5:
- no changes
---
 drivers/i2c/busses/i2c-meson.c | 23 +++++------------------
 1 file changed, 5 insertions(+), 18 deletions(-)

diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c
index 081d5b0c..8a088d26 100644
--- a/drivers/i2c/busses/i2c-meson.c
+++ b/drivers/i2c/busses/i2c-meson.c
@@ -55,7 +55,6 @@ enum {
 	STATE_IDLE,
 	STATE_READ,
 	STATE_WRITE,
-	STATE_STOP,
 };
 
 /**
@@ -208,19 +207,9 @@ static void meson_i2c_prepare_xfer(struct meson_i2c *i2c)
 
 	if (write)
 		meson_i2c_put_data(i2c, i2c->msg->buf + i2c->pos, i2c->count);
-}
-
-static void meson_i2c_stop(struct meson_i2c *i2c)
-{
-	dev_dbg(i2c->dev, "%s: last %d\n", __func__, i2c->last);
 
-	if (i2c->last) {
-		i2c->state = STATE_STOP;
+	if (i2c->last && i2c->pos + i2c->count >= i2c->msg->len)
 		meson_i2c_add_token(i2c, TOKEN_STOP);
-	} else {
-		i2c->state = STATE_IDLE;
-		complete(&i2c->done);
-	}
 }
 
 static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
@@ -265,7 +254,8 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
 		}
 
 		if (i2c->pos >= i2c->msg->len) {
-			meson_i2c_stop(i2c);
+			i2c->state = STATE_IDLE;
+			complete(&i2c->done);
 			break;
 		}
 
@@ -275,16 +265,13 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id)
 		i2c->pos += i2c->count;
 
 		if (i2c->pos >= i2c->msg->len) {
-			meson_i2c_stop(i2c);
+			i2c->state = STATE_IDLE;
+			complete(&i2c->done);
 			break;
 		}
 
 		meson_i2c_prepare_xfer(i2c);
 		break;
-	case STATE_STOP:
-		i2c->state = STATE_IDLE;
-		complete(&i2c->done);
-		break;
 	}
 
 out:
-- 
2.12.0

  parent reply	other threads:[~2017-03-25 13:14 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-25 12:57 [PATCH v5 00/10] i2c: meson: series with improvements Heiner Kallweit
2017-03-25 12:58 ` [PATCH v5 01/10] i2c: meson: use min instead of min_t where min_t isn't needed Heiner Kallweit
2017-03-25 13:01 ` [PATCH v5 02/10] i2c: meson: remove member irq from struct meson_i2c Heiner Kallweit
2017-03-25 13:04 ` [PATCH v5 03/10] i2c: meson: set clock divider in probe instead of setting it for each transfer Heiner Kallweit
2017-03-25 13:06 ` [PATCH v5 04/10] i2c: meson: use i2c core for DT clock-frequency parsing Heiner Kallweit
2017-03-25 13:07 ` [PATCH v5 05/10] i2c: meson: use full 12 bits for clock divider Heiner Kallweit
2017-03-25 13:09 ` [PATCH v5 06/10] i2c: meson: remove variable count from meson_i2c_xfer Heiner Kallweit
2017-03-25 13:10 ` [PATCH v5 07/10] i2c: meson: improve interrupt handler and detect spurious interrupts Heiner Kallweit
2017-03-25 13:11 ` Heiner Kallweit [this message]
2017-03-25 13:12 ` [PATCH v5 09/10] i2c: meson: remove meson_i2c_write_tokens Heiner Kallweit
2017-03-25 13:14 ` [PATCH v5 10/10] i2c: meson: improve and simplify interrupt handler Heiner Kallweit
2017-03-30 15:56 ` [PATCH v5 00/10] i2c: meson: series with improvements Wolfram Sang

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=df09e8d9-71ae-2c7f-5a02-940e39d6de92@gmail.com \
    --to=hkallweit1@gmail.com \
    --cc=jbrunet@baylibre.com \
    --cc=khilman@baylibre.com \
    --cc=linux-amlogic@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=wsa@the-dreams.de \
    /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).