[PATCH 1/6] rtc: sun6i: Expose the 32kHz oscillator

[Alexandre Belloni]

Hi,

On 20/01/2017 at 16:56:38 +0100, Maxime Ripard wrote :
> +
> +	rtc = kzalloc(sizeof(*rtc), GFP_KERNEL);
> +	if (!rtc)
> +		pr_crit("Can't allocate RTC structure\n");
> +

The message is unnecessary but you probably want to stop there and
return.

> +	rtc->base = of_io_request_and_map(node, 0, of_node_full_name(node));
> +	if (!rtc->base) {
> +		pr_crit("Can't map RTC registers");
> +		return;
> +	}
> +
> +	rtc->int_osc = clk_hw_register_fixed_rate_with_accuracy(NULL,
> +								"rtc-int-osc",
> +								NULL, 0,
> +								667000,
> +								300000000);
> +	if (IS_ERR(rtc->int_osc)) {
> +		pr_crit("Couldn't register the internal oscillator\n");
> +		return;
> +	}
> +
> +	/*
> +	 * Due to the missing clocks property we had to express the
> +	 * parenthood with the external oscillator that cannot fix (or
> +	 * at least expect to have) in the old DTs, we have to be a
> +	 * bit smart here.
> +	 *
> +	 * We deal with that by simply registering the internal
> +	 * oscillator as our parent in all cases, and try to get the
> +	 * external oscillator from the DT.
> +	 *
> +	 * In the case where we don't have it, of_clk_get_parent_name
> +	 * will return NULL, which is ok, and of_clk_get_parent_count
> +	 * will return 0, which is fine too. We will just register a
> +	 * single parent, everything works.
> +	 */
> +	parents[0] = clk_hw_get_name(rtc->int_osc);
> +	parents[1] = of_clk_get_parent_name(node, 0);
> +
> +	rtc->hw.init = &init;
> +
> +	init.parent_names = parents;
> +	init.num_parents = of_clk_get_parent_count(node) + 1;
> +	init.name = "rtc-osc";
> +	of_property_read_string(node, "clock-output-names", &init.name);
> +
> +	rtc->losc = clk_register(NULL, &rtc->hw);
> +	if (IS_ERR(rtc->losc)) {
> +		pr_crit("Couldn't register the LOSC clock\n");
> +		return;
> +	}
> +
> +	of_clk_add_hw_provider(node, of_clk_hw_simple_get, &rtc->hw);
> +
> +	/* Yes, I know, this is ugly. */
> +	sun6i_rtc = rtc;
> +}
> +CLK_OF_DECLARE_DRIVER(sun6i_rtc_clk, "allwinner,sun6i-a31-rtc",
> +		      sun6i_rtc_clk_init);
> +
>  static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id)
>  {
>  	struct sun6i_rtc_dev *chip = (struct sun6i_rtc_dev *) id;
> @@ -349,22 +476,15 @@ static const struct rtc_class_ops sun6i_rtc_ops = {
>  
>  static int sun6i_rtc_probe(struct platform_device *pdev)
>  {
> -	struct sun6i_rtc_dev *chip;
> -	struct resource *res;
> +	struct sun6i_rtc_dev *chip = sun6i_rtc;
>  	int ret;
>  
> -	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
>  	if (!chip)
> -		return -ENOMEM;
> +		return -ENODEV;
>  
>  	platform_set_drvdata(pdev, chip);
>  	chip->dev = &pdev->dev;
>  
> -	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -	chip->base = devm_ioremap_resource(&pdev->dev, res);
> -	if (IS_ERR(chip->base))
> -		return PTR_ERR(chip->base);
> -
>  	chip->irq = platform_get_irq(pdev, 0);
>  	if (chip->irq < 0) {
>  		dev_err(&pdev->dev, "No IRQ resource\n");
> @@ -404,6 +524,8 @@ static int sun6i_rtc_probe(struct platform_device *pdev)
>  	/* disable alarm wakeup */
>  	writel(0, chip->base + SUN6I_ALARM_CONFIG);
>  
> +	clk_prepare_enable(chip->losc);
> +
>  	chip->rtc = rtc_device_register("rtc-sun6i", &pdev->dev,
>  					&sun6i_rtc_ops, THIS_MODULE);
>  	if (IS_ERR(chip->rtc)) {
> -- 
> git-series 0.8.11

-- 
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com