Re: [PATCH v2 2/2] pwm: add this patch to support the new pwm of Rockchip SoCs

From: caesar
Date: Fri Jul 25 2014 - 06:29:50 EST


Hi Thierry,



å 2014å07æ21æ 21:27, Thierry Reding åé:
On Mon, Jul 21, 2014 at 08:58:42PM +0800, caesar wrote:
ä 2014å07æ21æ 16:50, Thierry Reding åé:
On Sat, Jul 19, 2014 at 08:55:29PM +0800, Caesar Wang wrote:
[...]
struct rockchip_pwm_chip *pc;
struct resource *r;
int ret;
@@ -119,7 +182,10 @@ static int rockchip_pwm_probe(struct platform_device *pdev)
return -ENOMEM;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pc->base = devm_ioremap_resource(&pdev->dev, r);
+ if (!strcmp(of_id->compatible, "rockchip,vop-pwm"))
+ pc->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+ else
+ pc->base = devm_ioremap_resource(&pdev->dev, r);
Sorry, this still isn't an option. You really shouldn't remap I/O
regions that other drivers may be using. You hinted at a shared register
space during the review of the initial version. Can you provide more
detail about what exactly the memory map looks like of the rk3288? Is
there some kind of technical reference manual that I could look at? Or
do you have a device tree extract that shows what the memory map looks
like?

Thierry
Maybe,you can look at the ARM: dts: rk3288:
https://github.com/rkchrome/kernel/blob/master/arch/arm/boot/dts/rk3288.dtsi
There is some lcdc and vop-pwm map address for rk3288.

,and you can look at the vop-introduce.pdf and vop-register.pdf in Annex.

Maybe,I should put the vop-pwm in lcdc driver,but I don't hope do so it.

Could you give a suggestion to solve it? Thanks.
It looks like you could turn the lcdc device into an MFD device so that
it can instantiate two devices, one for the display controller, the
other for the PWM. Or perhaps it would even work with only a single
child device.

The device tree would become something like this:

lcdc@ff930000 {
compatible = "rockchip,rk3288-lcdc";
...

pwm@ff9301a0 {
compatible = "rockchip,vop-pwm";
...
};
};

And your driver would do something like:

static const struct resource pwm_resources[] = {
{
.start = 0x1a0,
.end = 0x1af,
.flags = IORESOURCE_MEM,
},
};

static const struct mfd_cell subdevices[] = {
{
.name = "pwm",
.id = 1,
.of_compatible = "rockchip,vop-pwm",
.num_resources = ARRAY_SIZE(pwm_resources),
.resources = pwm_resources,
},
};

static int lcdc_probe(struct platform_device *pdev)
{
struct resource *regs;
...

regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);

...

err = mfd_add_devices(&pdev->dev, 0, subdevices, ARRAY_SIZE(subdevices),
regs, NULL, NULL);
...
}

Thierry
Sorry,I might a little trouble for the changes.

The driver changes only for lcdc? If that is the case,I suddenly don't know how to do it ?

Maybe,I didn't say it clearly.

lcdc0: lcdc@ff930000 | vop0pwm: pwm@ff9301a0
reg = <0xff930000 0x10000> | reg = <0xff9301a0 0x10>;

The lcdc has to add resource's address from 0xff930000 to 0xff93ffff.

When the pwm driver is loading vop0pwm. the "devm_ioremap_resource()" will be used in probe();

I think it will be occur a fail. because the resource [mem 0xff9301a0-0xff9301af] has be requested by lcdc.
=>rockchip-pwm ff9301a0.pwm: can't request region for resource [mem 0xff9301a0-0xff9301af]

If I do the changes in pwm driver,do you have a other suggestion for it? thanks.:-)


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