On Mon, 14 Feb 2011, Marek Vasut wrote: > On Sunday 13 February 2011 13:12:12 Julia Lawall wrote: > > Request_region should be used with release_region, not release_resource. > > > > The result of request_mem_region is no longer stored. Instead the field > > ioarea is used to store a pointer to the resource structure that contains > > the start address. This is the information that is needed later in > > nuc900_i2c_remove to release the region. The field ioarea is also printed > > in some debugging code. > > > > The semantic match that finds this problem is as follows: > > (http://coccinelle.lip6.fr/) > > > > // <smpl> > > @@ > > expression x,E; > > @@ > > ( > > *x = request_region(...) > > > > *x = request_mem_region(...) > > ) > > ... when != release_region(x) > > when != x = E > > * release_resource(x); > > // </smpl> > > > > Signed-off-by: Julia Lawall <julia@xxxxxxx> > > > > --- > > Not compiled due to incompatible architecture. > > > > drivers/i2c/busses/i2c-nuc900.c | 13 +++++-------- > > 1 file changed, 5 insertions(+), 8 deletions(-) > > > > diff --git a/drivers/i2c/busses/i2c-nuc900.c > > b/drivers/i2c/busses/i2c-nuc900.c index 7243426..97b16b7 100644 > > --- a/drivers/i2c/busses/i2c-nuc900.c > > +++ b/drivers/i2c/busses/i2c-nuc900.c > > @@ -568,15 +568,13 @@ static int __devinit nuc900_i2c_probe(struct > > platform_device *pdev) goto err_clk; > > } > > > > - i2c->ioarea = request_mem_region(res->start, resource_size(res), > > - pdev->name); > > - > > - if (i2c->ioarea == NULL) { > > + if (!request_mem_region(res->start, resource_size(res), pdev->name)) { > > I prefer the original version here -- it's clearer and also, doesn't the new > version violate line-over-80 principle ? The line ends before column 80. I'm not sure that the result of request_mem_region is the proper argment to give to release_region. In any case, all of the other calls to request_mem_region that do use release_region do not use the return value. They just test it directly as I have done here. julia > > dev_err(&pdev->dev, "cannot request IO\n"); > > ret = -ENXIO; > > goto err_clk; > > } > > > > + i2c->ioarea = res; > > i2c->regs = ioremap(res->start, resource_size(res)); > > > > if (i2c->regs == NULL) { > > @@ -645,8 +643,7 @@ static int __devinit nuc900_i2c_probe(struct > > platform_device *pdev) iounmap(i2c->regs); > > > > err_ioarea: > > - release_resource(i2c->ioarea); > > - kfree(i2c->ioarea); > > + release_mem_region(res->start, resource_size(res)); > > > > err_clk: > > clk_disable(i2c->clk); > > @@ -665,6 +662,7 @@ static int __devinit nuc900_i2c_probe(struct > > platform_device *pdev) static int __devexit nuc900_i2c_remove(struct > > platform_device *pdev) { > > struct nuc900_i2c *i2c = platform_get_drvdata(pdev); > > + struct resource *res = i2c->ioarea; > > No need for this ... > > > > i2c_del_adapter(&i2c->adap); > > free_irq(i2c->irq, i2c); > > @@ -674,8 +672,7 @@ static int __devexit nuc900_i2c_remove(struct > > platform_device *pdev) > > > > iounmap(i2c->regs); > > > > - release_resource(i2c->ioarea); > > - kfree(i2c->ioarea); > > ... the i2c pointer is still available here, why introducing struct resource > *res. release_mem_region() looks like a sane change to me though. > > > + release_mem_region(res->start, resource_size(res)); > > kfree(i2c); > > > > return 0; > -- > To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
