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USB: Remove redundant test in pxa27x_udc and ftdi_sio
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priv is checked not to be NULL near the beginning of the function and not
changed subsequently, making the test redundant.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
  S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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Julia Lawall authored and Greg Kroah-Hartman committed Mar 24, 2009
1 parent db5e6df commit 00185a6
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Showing 2 changed files with 8 additions and 10 deletions.
2 changes: 1 addition & 1 deletion drivers/usb/gadget/pxa27x_udc.c
Original file line number Diff line number Diff line change
Expand Up @@ -279,7 +279,7 @@ static void pxa_init_debugfs(struct pxa_udc *udc)
goto err_queues;
eps = debugfs_create_file("epstate", 0400, root, udc,
&eps_dbg_fops);
if (!queues)
if (!eps)
goto err_eps;

udc->debugfs_root = root;
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16 changes: 7 additions & 9 deletions drivers/usb/serial/ftdi_sio.c
Original file line number Diff line number Diff line change
Expand Up @@ -1938,15 +1938,13 @@ static void ftdi_process_read(struct work_struct *work)
/* Compare new line status to the old one, signal if different/
N.B. packet may be processed more than once, but differences
are only processed once. */
if (priv != NULL) {
char new_status = data[packet_offset + 0] &
FTDI_STATUS_B0_MASK;
if (new_status != priv->prev_status) {
priv->diff_status |=
new_status ^ priv->prev_status;
wake_up_interruptible(&priv->delta_msr_wait);
priv->prev_status = new_status;
}
char new_status = data[packet_offset + 0] &
FTDI_STATUS_B0_MASK;
if (new_status != priv->prev_status) {
priv->diff_status |=
new_status ^ priv->prev_status;
wake_up_interruptible(&priv->delta_msr_wait);
priv->prev_status = new_status;
}

length = min(PKTSZ, urb->actual_length-packet_offset)-2;
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