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 <[email protected]> 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 <[email protected]> Signed-off-by: Haojian Zhuang <[email protected]> Signed-off-by: Samuel Ortiz <[email protected]> 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) +#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: -- 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/
