Am 07.10.2012 18:50, schrieb Julia Lawall: > On Sun, 7 Oct 2012, walter harms wrote: > >> >> >> Am 07.10.2012 17:38, schrieb Julia Lawall: >>> From: Julia Lawall <julia.law...@lip6.fr> >>> >>> Introduce use of I2c_MSG_READ/WRITE/OP, for readability. >>> >>> A length expressed as an explicit constant is also re-expressed as >>> the size >>> of the buffer in each case. >>> >>> A simplified version of the semantic patch that makes this change is as >>> follows: (http://coccinelle.lip6.fr/) >>> >>> // <smpl> >>> @@ >>> expression a,b,c; >>> identifier x; >>> @@ >>> >>> struct i2c_msg x = >>> - {.addr = a, .buf = b, .len = c, .flags = I2C_M_RD} >>> + I2C_MSG_READ(a,b,c) >>> ; >>> >>> @@ >>> expression a,b,c; >>> identifier x; >>> @@ >>> >>> struct i2c_msg x = >>> - {.addr = a, .buf = b, .len = c, .flags = 0} >>> + I2C_MSG_WRITE(a,b,c) >>> ; >>> >>> @@ >>> expression a,b,c,d; >>> identifier x; >>> @@ >>> >>> struct i2c_msg x = >>> - {.addr = a, .buf = b, .len = c, .flags = d} >>> + I2C_MSG_OP(a,b,c,d) >>> ; >>> // </smpl> >>> >>> Signed-off-by: Julia Lawall <julia.law...@lip6.fr> >>> >>> --- >>> drivers/media/tuners/fc0011.c | 9 +++------ >>> 1 file changed, 3 insertions(+), 6 deletions(-) >>> >>> diff --git a/drivers/media/tuners/fc0011.c >>> b/drivers/media/tuners/fc0011.c >>> index e488254..5dbba98 100644 >>> --- a/drivers/media/tuners/fc0011.c >>> +++ b/drivers/media/tuners/fc0011.c >>> @@ -80,8 +80,7 @@ struct fc0011_priv { >>> static int fc0011_writereg(struct fc0011_priv *priv, u8 reg, u8 val) >>> { >>> u8 buf[2] = { reg, val }; >>> - struct i2c_msg msg = { .addr = priv->addr, >>> - .flags = 0, .buf = buf, .len = 2 }; >>> + struct i2c_msg msg = I2C_MSG_WRITE(priv->addr, buf, sizeof(buf)); >>> >>> if (i2c_transfer(priv->i2c, &msg, 1) != 1) { >>> dev_err(&priv->i2c->dev, >>> @@ -97,10 +96,8 @@ static int fc0011_readreg(struct fc0011_priv >>> *priv, u8 reg, u8 *val) >>> { >>> u8 dummy; >>> struct i2c_msg msg[2] = { >>> - { .addr = priv->addr, >>> - .flags = 0, .buf = ®, .len = 1 }, >>> - { .addr = priv->addr, >>> - .flags = I2C_M_RD, .buf = val ? : &dummy, .len = 1 }, >>> + I2C_MSG_WRITE(priv->addr, ®, sizeof(reg)), >>> + I2C_MSG_READ(priv->addr, val ? : &dummy, sizeof(dummy)), >>> }; >>> >> >> This dummy looks strange, can it be that this is used uninitialised ? > > I'm not sure to understand the question. The read, when it happens in > i2c_transfer will initialize dummy. On the other hand, I don't know > what i2c_transfer does when the buffer is NULL and the size is 1. It > does not look very elegant at least. >
mea culpa, i mixed read and write re, wh > julia > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
