Re: [PATCH 2/3] tegra: pwm-backlight: add tegra pwm-bl driver
From: Mark Zhang <hidden>
Date: 2013-01-21 07:36:08
Also in:
linux-tegra, lkml
On 01/19/2013 06:30 PM, Alexandre Courbot wrote:
Add a PWM-backlight subdriver for Tegra boards, with support for Ventana. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> ---
[...]
+ backlight {
+ compatible = "pwm-backlight-ventana";
+ brightness-levels = <0 16 32 48 64 80 96 112 128 144 160 176 192 208 224 240 255>;
+ default-brightness-level = <12>;
+
+ pwms = <&pwm 2 5000000>;After read the codes of tegra pwm driver & pwm framework, I got to know the meaning of this property. So I think we need to add a doc(e.g: Documentation/devicetree/bindings/video/backlight/nvidia,tegra20-bl.txt) to explain this, "Documentation/devicetree/bindings/pwm/pwm.txt" doesn't explain this, because this may be different between different pwm drivers.
+ pwm-names = "backlight"; + + power-supply = <&vdd_bl_reg>; + panel-supply = <&vdd_pnl_reg>; + bl-gpio = <&gpio 28 0>; + bl-panel = <&gpio 10 0>; + }; +
[...]
quoted hunk ↗ jump to hunk
diff --git a/drivers/video/backlight/pwm_bl_tegra.c b/drivers/video/backlight/pwm_bl_tegra.c new file mode 100644 index 0000000..8f2195b --- /dev/null +++ b/drivers/video/backlight/pwm_bl_tegra.c
So according to the filename, I think we can put all tegra boards codes here, right? Just like what you do for Ventana, if I wanna add support for cardhu, I can define similar functions -- let's say "init_cardhu", "exit_cardhu", "notify_cardhu" and "notify_after_cardhu", right? But I think if we do in this way, the file will become very long soon. And there are a lot of redundant codes in it. So do you have any suggestions? Mark
quoted hunk ↗ jump to hunk
@@ -0,0 +1,159 @@ +/* + * pwm-backlight subdriver for Tegra. + * + * Copyright (c) 2013 NVIDIA CORPORATION. All rights reserved. + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */
[...]
+MODULE_DESCRIPTION("Backlight Driver for Tegra boards");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pwm-tegra-backlight");
+
+