Re: [PATCH v3 2/2] pwm: rockchip: Added to support for RK3288 SoC

[caesar]

Hi Heiko,

在 2014年07月24日 16:05, Heiko Stübner 写道:

Hi caesar.

Am Donnerstag, 24. Juli 2014, 10:13:55 schrieb caesar:

+static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip, bool
enable)
+{
+       struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+       u32 val = 0;
+       u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
+
+       val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+
+       if (enable)
+               val |= enable_conf;
+       else
+               val &= ~enable_conf;
+
+       writel_relaxed(val, pc->base + pc->data->regs.ctrl);
+}
+
+static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip, bool
enable)
+{
+       struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+       u32 val = 0;
+       u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+               PWM_CONTINUOUS | PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
+
+       val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+
+       if (enable)
+               val |= enable_conf;
+       else
+               val &= ~enable_conf;
+
+       writel_relaxed(val, pc->base + pc->data->regs.ctrl);
+}
+
+static void rockchip_pwm_set_enable_vop(struct pwm_chip *chip, bool
enable) +{
+       struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+       u32 val = 0;
+       u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+               PWM_CONTINUOUS | PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
+
+       val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+
+       if (enable)
+               val |= enable_conf;
+       else
+               val &= ~enable_conf;
+
+       writel_relaxed(val, pc->base + pc->data->regs.ctrl);
+}

not sure if I'm just blind ... do rockchip_pwm_set_enable_v2 and
rockchip_pwm_set_enable_vop differ at all?

If they don't differ, I guess pwm_data_vop should just use
rockchip_pwm_set_enable_v2 instead of duplicating it.

Yes, the rockchip_pwm_set_enable_v1 & v2 & vop is similar.

So my v2 patch use "u32 enable_conf" instead of it .
+struct rockchip_pwm_data {

  > + .........
  > + u32 enable_conf;
  > +};

The thierry has suggested it [1] in my v2 patch:

For this I think it would be more readable to provide function pointers
rather than a variable. That is:

        struct rockchip_pwm_data {
                ...
                int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm);
                int (*disable)(struct pwm_chip *chip, struct pwm_device *pwm);
        };
Then you can implement these for each variant of the chip and call them
from the common rockchip_pwm_enable(), somewhat like this.


Perhaps,thierry's suggestion I got it wrong.

Using the function pointers like Thierry suggested looks nice, so no I don't
think you got it wrong :-)

What I meant was to simply reuse the existing function
rockchip_pwm_set_enable_v2 when there is _no_ difference at all to
rockchip_pwm_set_enable_vop, like

static const struct rockchip_pwm_data pwm_data_v2 = {
        .regs.duty = PWM_LRC,
        .regs.period = PWM_HRC,
        .regs.cntr = PWM_CNTR,
        .regs.ctrl = PWM_CTRL,
        .prescaler = PRESCALER-1,
        .set_enable = rockchip_pwm_set_enable_v2,
};

static const struct rockchip_pwm_data pwm_data_vop = {
        .regs.duty = PWM_LRC,
        .regs.period = PWM_HRC,
        .regs.cntr = PWM_CTRL,
        .regs.ctrl = PWM_CNTR,
        .prescaler = PRESCALER-1,
        .set_enable = rockchip_pwm_set_enable_v2,
};


Heiko

:-( ok, I will fix this and the other issuses in v4, thanks.

Hi thierry& Heiko :-)
Maybe,could you suggest solve it reasonable? thanks.

[1]: https://lkml.org/lkml/2014/7/21/113

+

   static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device

*pwm, int duty_ns, int period_ns)

   {

@@ -52,20 +126,20 @@ static int rockchip_pwm_config(struct pwm_chip
*chip,
struct pwm_device *pwm, * default prescaler value for all practical clock
rate values.

         */
        
        div = clk_rate * period_ns;

-       do_div(div, PRESCALER * NSEC_PER_SEC);
+       do_div(div, pc->data->prescaler * NSEC_PER_SEC);

        period = div;
        
        div = clk_rate * duty_ns;

-       do_div(div, PRESCALER * NSEC_PER_SEC);
+       do_div(div, pc->data->prescaler * NSEC_PER_SEC);

        duty = div;
        
        ret = clk_enable(pc->clk);
        if (ret)
        
                return ret;

-       writel(period, pc->base + PWM_LRC);
-       writel(duty, pc->base + PWM_HRC);
-       writel(0, pc->base + PWM_CNTR);
+       writel(period, pc->base + pc->data->regs.period);
+       writel(duty, pc->base + pc->data->regs.duty);
+       writel(0, pc->base + pc->data->regs.cntr);

        clk_disable(pc->clk);

@@ -76,15 +150,12 @@ static int rockchip_pwm_enable(struct pwm_chip
*chip,
struct pwm_device *pwm) {

        struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
        int ret;

-       u32 val;

        ret = clk_enable(pc->clk);
        if (ret)
        
                return ret;

-       val = readl_relaxed(pc->base + PWM_CTRL);
-       val |= PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
-       writel_relaxed(val, pc->base + PWM_CTRL);
+       pc->data->set_enable(chip, true);

        return 0;

}

@@ -92,11 +163,8 @@ static int rockchip_pwm_enable(struct pwm_chip *chip,
struct pwm_device *pwm) static void rockchip_pwm_disable(struct pwm_chip
*chip, struct pwm_device *pwm) {

        struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);

-       u32 val;

-       val = readl_relaxed(pc->base + PWM_CTRL);
-       val &= ~(PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN);
-       writel_relaxed(val, pc->base + PWM_CTRL);
+       pc->data->set_enable(chip, false);

        clk_disable(pc->clk);

}

@@ -108,12 +176,52 @@ static const struct pwm_ops rockchip_pwm_ops = {

        .owner = THIS_MODULE,

};

+static const struct rockchip_pwm_data pwm_data_v1 = {
+       .regs.duty = PWM_HRC,
+       .regs.period = PWM_LRC,
+       .regs.cntr = PWM_CNTR,
+       .regs.ctrl = PWM_CTRL,
+       .prescaler = PRESCALER,
+       .set_enable = rockchip_pwm_set_enable_v1,
+};
+
+static const struct rockchip_pwm_data pwm_data_v2 = {
+       .regs.duty = PWM_LRC,
+       .regs.period = PWM_HRC,
+       .regs.cntr = PWM_CNTR,
+       .regs.ctrl = PWM_CTRL,
+       .prescaler = PRESCALER-1,
+       .set_enable = rockchip_pwm_set_enable_v2,
+};
+
+static const struct rockchip_pwm_data pwm_data_vop = {
+       .regs.duty = PWM_LRC,
+       .regs.period = PWM_HRC,
+       .regs.cntr = PWM_CTRL,
+       .regs.ctrl = PWM_CNTR,
+       .prescaler = PRESCALER-1,
+       .set_enable = rockchip_pwm_set_enable_vop,
+};
+
+static const struct of_device_id rockchip_pwm_dt_ids[] = {
+       { .compatible = "rockchip,rk2928-pwm", .data = &pwm_data_v1},
+       { .compatible = "rockchip,rk3288-pwm", .data = &pwm_data_v2},
+       { .compatible = "rockchip,vop-pwm", .data = &pwm_data_vop},
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
+

   static int rockchip_pwm_probe(struct platform_device *pdev)
   {

+       const struct of_device_id *id;

        struct rockchip_pwm_chip *pc;
        struct resource *r;
        int ret;

+       id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
+       if (!id)
+               return -EINVAL;
+

        pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
        if (!pc)
        
                return -ENOMEM;

@@ -133,6 +241,7 @@ static int rockchip_pwm_probe(struct platform_device
*pdev)

        platform_set_drvdata(pdev, pc);

+       pc->data = id->data;

        pc->chip.dev = &pdev->dev;
        pc->chip.ops = &rockchip_pwm_ops;
        pc->chip.base = -1;

@@ -156,12 +265,6 @@ static int rockchip_pwm_remove(struct
platform_device
*pdev) return pwmchip_remove(&pc->chip);

   }

-static const struct of_device_id rockchip_pwm_dt_ids[] = {
-       { .compatible = "rockchip,rk2928-pwm" },
-       { /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, rockchip_pwm_dt_ids);
-

   static struct platform_driver rockchip_pwm_driver = {

.driver = {

        
                .name = "rockchip-pwm",

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