From julia@diku.dk Wed Jan 21 09:18:11 2009 From: Julia Lawall Date: Fri, 19 Dec 2008 18:11:25 +0100 (CET) Subject: Staging: go7007: Move a dereference below a NULL test To: pete@sensoray.com, gregkh@suse.de, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Message-ID: From: Julia Lawall In each case, if the NULL test is necessary, then the dereference should be moved below the NULL test. The semantic patch that makes this change is as follows: (http://www.emn.fr/x-info/coccinelle/). The result has been modified to move the initialization of usb down closer to where it is used. // @@ type T; expression E; identifier i,fld; statement S; @@ - T i = E->fld; + T i; ... when != E when != i if (E == NULL) S + i = E->fld; // Signed-off-by: Julia Lawall Signed-off-by: Greg Kroah-Hartman --- drivers/staging/go7007/s2250-board.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/staging/go7007/s2250-board.c +++ b/drivers/staging/go7007/s2250-board.c @@ -149,7 +149,7 @@ static int go7007_usb_vendor_request(str static int write_reg(struct i2c_client *client, u8 reg, u8 value) { struct go7007 *go = i2c_get_adapdata(client->adapter); - struct go7007_usb *usb = go->hpi_context; + struct go7007_usb *usb; int rc; int dev_addr = client->addr; u8 *buf; @@ -164,6 +164,7 @@ static int write_reg(struct i2c_client * if (buf == NULL) return -ENOMEM; + usb = go->hpi_context; if (down_interruptible(&usb->i2c_lock) != 0) { printk(KERN_INFO "i2c lock failed\n"); return -EINTR; @@ -181,7 +182,7 @@ static int write_reg(struct i2c_client * static int write_reg_fp(struct i2c_client *client, u16 addr, u16 val) { struct go7007 *go = i2c_get_adapdata(client->adapter); - struct go7007_usb *usb = go->hpi_context; + struct go7007_usb *usb; u8 *buf; struct s2250 *dec = i2c_get_clientdata(client); @@ -200,6 +201,7 @@ static int write_reg_fp(struct i2c_clien memset(buf, 0xcd, 6); + usb = go->hpi_context; if (down_interruptible(&usb->i2c_lock) != 0) { printk(KERN_INFO "i2c lock failed\n"); return -EINTR;