[PATCH] usbvision: constify i2c_algorithm structure

From: Gustavo A. R. Silva
Date: Sun Jul 09 2017 - 18:04:55 EST


Check for i2c_algorithm structures that are only stored in
the algo field of an i2c_adapter structure. This field is
declared const, so i2c_algorithm structures that have this
property can be declared as const also.

This issue was identified using Coccinelle and the following
semantic patch:

@r disable optional_qualifier@
identifier i;
position p;
@@
static struct i2c_algorithm i@p = { ... };

@ok@
identifier r.i;
struct i2c_adapter e;
position p;
@@
e.algo = &i@p;

@bad@
position p != {r.p,ok.p};
identifier r.i;
@@
i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
struct i2c_algorithm i = { ... };

Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
---
drivers/media/usb/usbvision/usbvision-i2c.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/usb/usbvision/usbvision-i2c.c b/drivers/media/usb/usbvision/usbvision-i2c.c
index fdf6b6e..f86a0e0 100644
--- a/drivers/media/usb/usbvision/usbvision-i2c.c
+++ b/drivers/media/usb/usbvision/usbvision-i2c.c
@@ -163,7 +163,7 @@ static u32 functionality(struct i2c_adapter *adap)

/* -----exported algorithm data: ------------------------------------- */

-static struct i2c_algorithm usbvision_algo = {
+static const struct i2c_algorithm usbvision_algo = {
.master_xfer = usbvision_i2c_xfer,
.smbus_xfer = NULL,
.functionality = functionality,
--
2.5.0