On Thursday, July 25, 2013 12:42 AM, Olof Johansson wrote: > > The device-tree enablement for max8925 has several problems, but besides > the bindings being wrong (and not having seen review) there's also some > bad coding practices on how to fill in the platform_data from device tree. > > I came across this since it causes a warning when compiling > mmp2_defconfig, and instead of doing the minimal fix to silence the > warning, I restructured the code a bit. > > This silences the 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] > > Note that the bindings themselves need to be revisited too, but that will > affect more than just the backlight driver and is best done separately; > this just fixes the bad code for the backlight driver. > > Signed-off-by: Olof Johansson <[email protected]> > --- > > Richard, Jingoo, this would be good to see go into 3.11 if you're > comfortable with it.
CC'ed Andrew Morton Hi Olof Johansson, Currently, there is not git tree for Backlight subsystem. I hope that this would go into 3.11 through one of other trees with my Ack. If not, it will go into 3.12-rc1 through mm-tree. Acked-by: Jingoo Han <[email protected]> Best regards, Jingoo Han > > > -Olof > > drivers/video/backlight/max8925_bl.c | 41 > +++++++++++++++++----------------- > 1 file changed, 21 insertions(+), 20 deletions(-) > > diff --git a/drivers/video/backlight/max8925_bl.c > b/drivers/video/backlight/max8925_bl.c > index 5ca11b0..886e797 100644 > --- a/drivers/video/backlight/max8925_bl.c > +++ b/drivers/video/backlight/max8925_bl.c > @@ -101,33 +101,37 @@ 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) > +static void max8925_backlight_dt_init(struct platform_device *pdev) > { > struct device_node *nproot = pdev->dev.parent->of_node, *np; > - int dual_string; > + struct max8925_backlight_pdata *pdata; > + u32 val; > + > + if (!nproot || !IS_ENABLED(CONFIG_OF)) > + return; > + > + pdata = devm_kzalloc(&pdev->dev, > + sizeof(struct max8925_backlight_pdata), > + GFP_KERNEL); > + if (!pdata) > + return; > > - 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; > + return; > } > > - of_property_read_u32(np, "maxim,max8925-dual-string", &dual_string); > - pdata->dual_string = dual_string; > - return 0; > + if (!of_property_read_u32(np, "maxim,max8925-dual-string", &val)) > + pdata->dual_string = val; > + > + pdev->dev.platform_data = pdata; > } > -#else > -#define max8925_backlight_dt_init(x, y) (-1) > -#endif > > static int max8925_backlight_probe(struct platform_device *pdev) > { > struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); > - struct max8925_backlight_pdata *pdata = pdev->dev.platform_data; > + struct max8925_backlight_pdata *pdata; > struct max8925_backlight_data *data; > struct backlight_device *bl; > struct backlight_properties props; > @@ -170,13 +174,10 @@ 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 (!pdev->dev.platform_data) > + max8925_backlight_dt_init(pdev); > > + pdata = pdev->dev.platform_data; > if (pdata) { > if (pdata->lxw_scl) > value |= (1 << 7); > -- > 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
