[PATCH] staging: dgap: removes redundant null check and change paramter for dgap_maxcps_room()

From: Daeseok Youn
Date: Sun Jul 06 2014 - 21:29:15 EST


Null checks for tty, un and ch are already done by caller,
so replace parameter "tty" with "ch" and "un".

And also use a pointer for returning new bytes_available instead of
return variable.

Signed-off-by: Daeseok Youn <daeseok.youn@xxxxxxxxx>
---
drivers/staging/dgap/dgap.c | 29 +++++++----------------------
1 files changed, 7 insertions(+), 22 deletions(-)

diff --git a/drivers/staging/dgap/dgap.c b/drivers/staging/dgap/dgap.c
index e8d3c99..da11dfb 100644
--- a/drivers/staging/dgap/dgap.c
+++ b/drivers/staging/dgap/dgap.c
@@ -2507,31 +2507,18 @@ static int dgap_wait_for_drain(struct tty_struct *tty)
*
* Reduces bytes_available to the max number of characters
* that can be sent currently given the maxcps value, and
- * returns the new bytes_available. This only affects printer
+ * rewrites the new bytes_available. This only affects printer
* output.
*/
-static int dgap_maxcps_room(struct tty_struct *tty, int bytes_available)
+static void dgap_maxcps_room(struct channel_t *ch, struct un_t *un,
+ int *bytes_available)
{
- struct channel_t *ch;
- struct un_t *un;
-
- if (!tty)
- return bytes_available;
-
- un = tty->driver_data;
- if (!un || un->magic != DGAP_UNIT_MAGIC)
- return bytes_available;
-
- ch = un->un_ch;
- if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
- return bytes_available;
-
/*
* If its not the Transparent print device, return
* the full data amount.
*/
if (un->un_type != DGAP_PRINT)
- return bytes_available;
+ return;

if (ch->ch_digi.digi_maxcps > 0 && ch->ch_digi.digi_bufsize > 0) {
int cps_limit = 0;
@@ -2553,10 +2540,8 @@ static int dgap_maxcps_room(struct tty_struct *tty, int bytes_available)
cps_limit = 0;
}

- bytes_available = min(cps_limit, bytes_available);
+ *bytes_available = min(cps_limit, *bytes_available);
}
-
- return bytes_available;
}

static inline void dgap_set_firmware_event(struct un_t *un, unsigned int event)
@@ -2627,7 +2612,7 @@ static int dgap_tty_write_room(struct tty_struct *tty)
ret += ch->ch_tsize;

/* Limit printer to maxcps */
- ret = dgap_maxcps_room(tty, ret);
+ dgap_maxcps_room(ch, un, &ret);

/*
* If we are printer device, leave space for
@@ -2732,7 +2717,7 @@ static int dgap_tty_write(struct tty_struct *tty, const unsigned char *buf,
* Limit printer output to maxcps overall, with bursts allowed
* up to bufsize characters.
*/
- bufcount = dgap_maxcps_room(tty, bufcount);
+ dgap_maxcps_room(ch, un, &bufcount);

/*
* Take minimum of what the user wants to send, and the
--
1.7.1

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