Hello, On Tue, May 07, 2013 at 04:17:34AM -0500, Robin Holt wrote: > I noticed a warning while cross-compiling all arm defconfigs. > > The mmp2_defconfig gave this warning: > > drivers/video/backlight/max8925_bl.c: In function 'max8925_backlight_probe': > drivers/video/backlight/max8925_bl.c:177:3: warning: statement with no effect > [-Wunused-value] > > This appears to have been introduced by the above commit when !CONFIG_OF > > Looking at this more closely, I am not sure how this was ever intended > to be handled or how the errors returned in the CONFIG_OF case were > intended to be handled as the return from max8925_backlight_dt_init is > always ignored. > > I think this needs some more attention, but do not feel like I know > enough about it or have any means to test it to weigh in. > > Thanks, > Robin > > > commit 47ec340cb8e232671e7c4a4689ff32c3bdf329da > Author: Qing Xu <qi...@marvell.com> > Date: Mon Feb 4 23:40:45 2013 +0800 > > mfd: max8925: Support dt for backlight > > Add device tree support in max8925 backlight. > > Signed-off-by: Qing Xu <qi...@marvell.com> > Signed-off-by: Haojian Zhuang <haojian.zhu...@gmail.com> > Signed-off-by: Samuel Ortiz <sa...@linux.intel.com> > > diff --git a/drivers/video/backlight/max8925_bl.c > b/drivers/video/backlight/max8925_bl.c > index 2c9bce0..5ca11b0 100644 > --- a/drivers/video/backlight/max8925_bl.c > +++ b/drivers/video/backlight/max8925_bl.c > @@ -101,6 +101,29 @@ static const struct backlight_ops max8925_backlight_ops > = { > .get_brightness = max8925_backlight_get_brightness, > }; > > +#ifdef CONFIG_OF > +static int max8925_backlight_dt_init(struct platform_device *pdev, > + struct max8925_backlight_pdata *pdata) > +{ > + struct device_node *nproot = pdev->dev.parent->of_node, *np; > + int dual_string; > + > + if (!nproot) > + return -ENODEV; > + np = of_find_node_by_name(nproot, "backlight"); > + if (!np) { > + dev_err(&pdev->dev, "failed to find backlight node\n"); > + return -ENODEV; > + } > + > + of_property_read_u32(np, "maxim,max8925-dual-string", &dual_string); > + pdata->dual_string = dual_string; > + return 0; > +} > +#else > +#define max8925_backlight_dt_init(x, y) (-1) It's probably best to make this:
static inline max8925_backlight_dt_init(struct platform_device *pdev, struct max8925_backlight_pdata *pdata) { return -ENODEV; } > +#endif > + > static int max8925_backlight_probe(struct platform_device *pdev) > { > struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); > @@ -147,6 +170,13 @@ static int max8925_backlight_probe(struct > platform_device *pdev) > platform_set_drvdata(pdev, bl); > > value = 0; > + if (pdev->dev.parent->of_node && !pdata) { > + pdata = devm_kzalloc(&pdev->dev, > + sizeof(struct max8925_backlight_pdata), > + GFP_KERNEL); > + max8925_backlight_dt_init(pdev, pdata); > + } > + > if (pdata) { > if (pdata->lxw_scl) > value |= (1 << 7); > @@ -158,7 +188,6 @@ static int max8925_backlight_probe(struct platform_device > *pdev) > ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 0xfe, value); > if (ret < 0) > goto out_brt; > - > backlight_update_status(bl); > return 0; > out_brt: > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-ker...@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel > -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ | -- 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/