Re: [PATCH v3 3/3] backlight: as3711: add OF support
From: Andrew Morton <akpm@linux-foundation.org>
Date: 2013-03-25 22:40:50
Also in:
linux-devicetree, lkml
On Fri, 22 Mar 2013 17:15:49 +0100 Guennadi Liakhovetski [off-list ref] wrote:
quoted hunk ↗ jump to hunk
Add support for configuring AS3711 backlight driver from DT. Signed-off-by: Guennadi Liakhovetski <redacted> Reviwed-by: Mark Brown [off-list ref] --- drivers/video/backlight/as3711_bl.c | 118 ++++++++++++++++++++++++++++++++++- 1 files changed, 117 insertions(+), 1 deletions(-)diff --git a/drivers/video/backlight/as3711_bl.c b/drivers/video/backlight/as3711_bl.c index 41d52fe..123887c 100644 --- a/drivers/video/backlight/as3711_bl.c +++ b/drivers/video/backlight/as3711_bl.c@@ -258,6 +258,109 @@ static int as3711_bl_register(struct platform_device *pdev, return 0; } +static int as3711_backlight_parse_dt(struct device *dev) +{ + struct as3711_bl_pdata *pdata = dev_get_platdata(dev); + struct device_node *bl > + of_find_node_by_name(dev->parent->of_node, "backlight"), *fb; + int ret;
It's tidier to do struct device_node *bl; bl = of_find_node_by_name(dev->parent->of_node, "backlight"), *fb; and avoid the 80-col trickery.
quoted hunk ↗ jump to hunk
+ if (!bl) { + dev_dbg(dev, "backlight node not found\n"); + return -ENODEV; + } + + fb = of_parse_phandle(bl, "su1-dev", 0); + if (fb) { + pdata->su1_fb = fb->full_name; + + ret = of_property_read_u32(bl, "su1-max-uA", &pdata->su1_max_uA); + if (pdata->su1_max_uA <= 0) + ret = -EINVAL; + if (ret < 0) + return ret; + } + + fb = of_parse_phandle(bl, "su2-dev", 0); + if (fb) { + int count = 0; + + pdata->su2_fb = fb->full_name; + + ret = of_property_read_u32(bl, "su2-max-uA", &pdata->su2_max_uA); + if (pdata->su2_max_uA <= 0) + ret = -EINVAL; + if (ret < 0) + return ret; + + if (of_find_property(bl, "su2-feedback-voltage", NULL)) { + pdata->su2_feedback = AS3711_SU2_VOLTAGE; + count++; + } + if (of_find_property(bl, "su2-feedback-curr1", NULL)) { + pdata->su2_feedback = AS3711_SU2_CURR1; + count++; + } + if (of_find_property(bl, "su2-feedback-curr2", NULL)) { + pdata->su2_feedback = AS3711_SU2_CURR2; + count++; + } + if (of_find_property(bl, "su2-feedback-curr3", NULL)) { + pdata->su2_feedback = AS3711_SU2_CURR3; + count++; + } + if (of_find_property(bl, "su2-feedback-curr-auto", NULL)) { + pdata->su2_feedback = AS3711_SU2_CURR_AUTO; + count++; + } + if (count != 1) + return -EINVAL;
This looks odd. If the firmware provides both su2-feedback-voltage and su2-feedback-curr1, we fail? Firmware developers are notoriously flakey - can the code be more defensive here?
+ count = 0;
+ if (of_find_property(bl, "su2-fbprot-lx-sd4", NULL)) {
+ pdata->su2_fbprot = AS3711_SU2_LX_SD4;
+ count++;
+ }
+ if (of_find_property(bl, "su2-fbprot-gpio2", NULL)) {
+ pdata->su2_fbprot = AS3711_SU2_GPIO2;
+ count++;
+ }
+ if (of_find_property(bl, "su2-fbprot-gpio3", NULL)) {
+ pdata->su2_fbprot = AS3711_SU2_GPIO3;
+ count++;
+ }
+ if (of_find_property(bl, "su2-fbprot-gpio4", NULL)) {
+ pdata->su2_fbprot = AS3711_SU2_GPIO4;
+ count++;
+ }
+ if (count != 1)
+ return -EINVAL;
+
+ count = 0;
+ if (of_find_property(bl, "su2-auto-curr1", NULL)) {
+ pdata->su2_auto_curr1 = true;
+ count++;
+ }
+ if (of_find_property(bl, "su2-auto-curr2", NULL)) {
+ pdata->su2_auto_curr2 = true;
+ count++;
+ }
+ if (of_find_property(bl, "su2-auto-curr3", NULL)) {
+ pdata->su2_auto_curr3 = true;
+ count++;
+ }
+
+ /*
+ * At least one su2-auto-curr* must be specified iff
+ * AS3711_SU2_CURR_AUTO is used
+ */
+ if (!count ^ (pdata->su2_feedback != AS3711_SU2_CURR_AUTO))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
...