| Message ID | 20131217095658.GD13823@ulmo.nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Thierry Reding <thierry.reding@gmail.com> writes: > I hadn't anticipated that =(. In fact I had been holding this patch back > for a release cycle because I was waiting for a specific regulator patch > to land which provides a dummy regulator if one wasn't specified. It > seems that that patch only works when booting from DT, though. > > The correct way to fix this would be to provide a lookup table with the > dummy regulator in the board file. I've attached a patch (compile-tested > only) that might work. > > If it does, please let me know and, if nobody else volunteers, I'll see > if I can come up with a set of patches to fix this for any other boards > that have the same issue. Actually, it needs a very small "tweak" to work : - REGULATOR_SUPPLY("power", "pwm-backlight.0"), + REGULATOR_SUPPLY("power", "pwm-backlight"), Without it regulator_dev_lookup() won't match the device. Moreover, it requires a config option, CONFIG_REGULATOR_FIXED_VOLTAGE=y. That's not a problem for my specific platform, but I haven't seen *any* PXA platform with it activated, which means all defconfigs have to be patched, which is unfortunate. As for my specific mioa701, your change with the tweak is perfectly fine and tested. Cheers. -- Robert
On Tue, Dec 17, 2013 at 07:31:21PM +0100, Robert Jarzmik wrote: > Thierry Reding <thierry.reding@gmail.com> writes: > > > I hadn't anticipated that =(. In fact I had been holding this patch back > > for a release cycle because I was waiting for a specific regulator patch > > to land which provides a dummy regulator if one wasn't specified. It > > seems that that patch only works when booting from DT, though. > > > > The correct way to fix this would be to provide a lookup table with the > > dummy regulator in the board file. I've attached a patch (compile-tested > > only) that might work. > > > > If it does, please let me know and, if nobody else volunteers, I'll see > > if I can come up with a set of patches to fix this for any other boards > > that have the same issue. > Actually, it needs a very small "tweak" to work : > - REGULATOR_SUPPLY("power", "pwm-backlight.0"), > + REGULATOR_SUPPLY("power", "pwm-backlight"), > > Without it regulator_dev_lookup() won't match the device. > > Moreover, it requires a config option, CONFIG_REGULATOR_FIXED_VOLTAGE=y. That's > not a problem for my specific platform, Okay. I'll submit a patch with that tweak of yours rolled in and Haojian can merge that via the PXA tree. > but I haven't seen *any* PXA platform > with it activated, which means all defconfigs have to be patched, which is > unfortunate. Unfortunate indeed! > As for my specific mioa701, your change with the tweak is perfectly fine and > tested. Great, I'll add your Tested-by. Thanks, Thierry
From 8c25d9b1465acd2dcd05644f2c984b54ae3dfc53 Mon Sep 17 00:00:00 2001 From: Thierry Reding <thierry.reding@gmail.com> Date: Tue, 17 Dec 2013 10:52:36 +0100 Subject: [PATCH] ARM: pxa: Add dummy power supply for backlight for Mitac Mio A701 Recent changes to the pwm-backlight driver have made the power supply mandatory. There is code in the regulator core to deal with situations where no regulator is specified and provide a dummy, but that works on DT-based boards only. The situation can be remedied by adding a dummy regulator during board initialization. Signed-off-by: Thierry Reding <thierry.reding@gmail.com> --- arch/arm/mach-pxa/mioa701.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/mach-pxa/mioa701.c b/arch/arm/mach-pxa/mioa701.c index f70583fee59f..5cb3a3b33772 100644 --- a/arch/arm/mach-pxa/mioa701.c +++ b/arch/arm/mach-pxa/mioa701.c @@ -38,6 +38,7 @@ #include <linux/mtd/physmap.h> #include <linux/usb/gpio_vbus.h> #include <linux/reboot.h> +#include <linux/regulator/fixed.h> #include <linux/regulator/max1586.h> #include <linux/slab.h> #include <linux/i2c/pxa-i2c.h> @@ -714,6 +715,10 @@ static struct gpio global_gpios[] = { { GPIO56_MT9M111_nOE, GPIOF_OUT_INIT_LOW, "Camera nOE" }, }; +static struct regulator_consumer_supply fixed_5v0_consumers[] = { + REGULATOR_SUPPLY("power", "pwm-backlight.0"), +}; + static void __init mioa701_machine_init(void) { int rc; @@ -753,6 +758,10 @@ static void __init mioa701_machine_init(void) pxa_set_i2c_info(&i2c_pdata); pxa27x_set_i2c_power_info(NULL); pxa_set_camera_info(&mioa701_pxacamera_platform_data); + + regulator_register_always_on(0, "fixed-5.0V", fixed_5v0_consumers, + ARRAY_SIZE(fixed_5v0_consumers), + 5000000); } static void mioa701_machine_exit(void) -- 1.8.4.2