[PATCH 1/6] rtc: sun6i: Expose the 32kHz oscillator
From: Alexandre Belloni <hidden>
Date: 2017-01-22 14:17:08
Also in:
linux-devicetree, linux-rtc
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.
quoted hunk
+ 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