| Message ID | 20180915105430.24052-1-yuehaibing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [-next] iio: potentiometer: mcp4531: merge calls to of_match_device and of_device_get_match_data | expand |
On 2018-09-15 12:54, YueHaibing wrote: > Drop call to of_match_device, which is subsumed by the subsequent > call to of_device_get_match_data. The code becomes simpler, and a > temporary variable can be dropped. > > Found by coccinelle. > > Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Peter Rosin <peda@axentia.se> Cheers, Peter
On Sat, Sep 15, 2018 at 06:54:30PM +0800, YueHaibing wrote: > Drop call to of_match_device, which is subsumed by the subsequent > call to of_device_get_match_data. The code becomes simpler, and a > temporary variable can be dropped. > > Found by coccinelle. > > Signed-off-by: YueHaibing <yuehaibing@huawei.com> Already applied! https://lore.kernel.org/lkml/20180819201752.2280be76@archlinux/ Anyway, if you want to work on making similar changes, you may refer the following cocci script: I tested[1] the changes through 0-day and had few false positives and regressions. Therefore, check the results and compile test the changes before sending patches. Julia, and I had tried to make the confidence "High" but few cases were difficult to resolve, and later neither of us had time to look back at it again. Not all maintainers will acknowledge such a change, but IIRC Rob Herring gave a thumbs up on few cases on the dt-mailing list. [1] https://github.com/himanshujha199640/linux-next/commit/efb7ed923bd00c86fe0a4e67e2ddb636ff0e0ff4 --------------------------------------------------------------------- /// Use of_device_get_match_data() to get matched data in an OF driver //# of_device_get_match_data() returns const * and therefore the left //# argument of assignment should also be a const * for compatible //# types. /// // Confidence: Moderate // Copyright: (C) 2018 Himanshu Jha, GPLv2. // Copyright: (C) 2018 Julia Lawall, INRIA/LIP6. GPLv2. // Keywords: of_match_device, of_device_get_match_data virtual patch virtual context virtual org virtual report @r1 depends on patch && !context && !org && !report@ expression x,y,z; identifier match; type T; statement S; @@ - match = of_match_device(x, y); ( - if(match==NULL) S - z = match->data; + z = of_device_get_match_data(y); | - if(match==NULL) S - z = (T *)match->data; + z = of_device_get_match_data(y); | - if(match==NULL) S - z = (T)match->data; + z = (T)of_device_get_match_data(y); | - if(match!= NULL) - z = match->data; + z = of_device_get_match_data(y); | - if(match!= NULL) - z = (T *)match->data; + z = of_device_get_match_data(y); | - if(match!= NULL) - z = (T)match->data; + z = (T)of_device_get_match_data(y); ) ... when != match @r2 depends on r1 && patch && !context && !org && !report@ type T1; expression e; identifier r1.match; @@ ( - T1 match = e; | - T1 match; ) // ---------------------------------------------------------------------------- @r1_context depends on !patch && (context || org || report)@ type T; identifier match; statement S; expression x, y, z; position j0, j1; @@ * match@j0 = of_match_device(x, y); ( * if(match==NULL) S * z = match@j1->data; | * if(match==NULL) S * z = (T *)match@j1->data; | * if(match==NULL) S * z = (T)match@j1->data; | * if(match!= NULL) * z = match@j1->data; | * if(match!= NULL) * z = (T *)match@j1->data; | * if(match!= NULL) * z = (T)match@j1->data; ) ... when != match @r2_context depends on r1 && !patch && (context || org || report)@ type T1; identifier r1_context.match; expression e; position j0; @@ ( * T1 match@j0 = e; | * T1 match@j0; ) // ---------------------------------------------------------------------------- @script:python r1_org depends on org@ j0 << r1_context.j0; j1 << r1_context.j1; @@ msg = "WARNING: opportunity for of_device_get_match_data." coccilib.org.print_todo(j0[0], msg) coccilib.org.print_link(j1[0], "") // ---------------------------------------------------------------------------- @script:python r1_report depends on report@ j0 << r1_context.j0; j1 << r1_context.j1; @@ msg = "WARNING: opportunity for of_device_get_match_data around line %s." % (j1[0].line) coccilib.report.print_report(j0[0], msg) --------------------------------------------------------------------- Thanks
diff --git a/drivers/iio/potentiometer/mcp4531.c b/drivers/iio/potentiometer/mcp4531.c index df894af..d87ca85 100644 --- a/drivers/iio/potentiometer/mcp4531.c +++ b/drivers/iio/potentiometer/mcp4531.c @@ -360,7 +360,6 @@ static int mcp4531_probe(struct i2c_client *client) struct device *dev = &client->dev; struct mcp4531_data *data; struct iio_dev *indio_dev; - const struct of_device_id *match; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) { @@ -375,10 +374,8 @@ static int mcp4531_probe(struct i2c_client *client) i2c_set_clientdata(client, indio_dev); data->client = client; - match = of_match_device(of_match_ptr(mcp4531_of_match), dev); - if (match) - data->cfg = of_device_get_match_data(dev); - else + data->cfg = of_device_get_match_data(dev); + if (!data->cfg) data->cfg = &mcp4531_cfg[i2c_match_id(mcp4531_id, client)->driver_data]; indio_dev->dev.parent = dev;
Drop call to of_match_device, which is subsumed by the subsequent call to of_device_get_match_data. The code becomes simpler, and a temporary variable can be dropped. Found by coccinelle. Signed-off-by: YueHaibing <yuehaibing@huawei.com> --- drivers/iio/potentiometer/mcp4531.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)