diff options
Diffstat (limited to 'drivers/rtc/rtc-sun6i.c')
| -rw-r--r-- | drivers/rtc/rtc-sun6i.c | 182 |
1 files changed, 153 insertions, 29 deletions
diff --git a/drivers/rtc/rtc-sun6i.c b/drivers/rtc/rtc-sun6i.c index c169a2cd4727..39cbc1238b92 100644 --- a/drivers/rtc/rtc-sun6i.c +++ b/drivers/rtc/rtc-sun6i.c @@ -20,6 +20,8 @@ * more details. */ +#include <linux/clk.h> +#include <linux/clk-provider.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/fs.h> @@ -33,15 +35,20 @@ #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/rtc.h> +#include <linux/slab.h> #include <linux/types.h> /* Control register */ #define SUN6I_LOSC_CTRL 0x0000 +#define SUN6I_LOSC_CTRL_KEY (0x16aa << 16) #define SUN6I_LOSC_CTRL_ALM_DHMS_ACC BIT(9) #define SUN6I_LOSC_CTRL_RTC_HMS_ACC BIT(8) #define SUN6I_LOSC_CTRL_RTC_YMD_ACC BIT(7) +#define SUN6I_LOSC_CTRL_EXT_OSC BIT(0) #define SUN6I_LOSC_CTRL_ACC_MASK GENMASK(9, 7) +#define SUN6I_LOSC_CLK_PRESCAL 0x0008 + /* RTC */ #define SUN6I_RTC_YMD 0x0010 #define SUN6I_RTC_HMS 0x0014 @@ -114,13 +121,142 @@ struct sun6i_rtc_dev { void __iomem *base; int irq; unsigned long alarm; + + struct clk_hw hw; + struct clk_hw *int_osc; + struct clk *losc; + + spinlock_t lock; +}; + +static struct sun6i_rtc_dev *sun6i_rtc; + +static unsigned long sun6i_rtc_osc_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw); + u32 val; + + val = readl(rtc->base + SUN6I_LOSC_CTRL); + if (val & SUN6I_LOSC_CTRL_EXT_OSC) + return parent_rate; + + val = readl(rtc->base + SUN6I_LOSC_CLK_PRESCAL); + val &= GENMASK(4, 0); + + return parent_rate / (val + 1); +} + +static u8 sun6i_rtc_osc_get_parent(struct clk_hw *hw) +{ + struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw); + + return readl(rtc->base + SUN6I_LOSC_CTRL) & SUN6I_LOSC_CTRL_EXT_OSC; +} + +static int sun6i_rtc_osc_set_parent(struct clk_hw *hw, u8 index) +{ + struct sun6i_rtc_dev *rtc = container_of(hw, struct sun6i_rtc_dev, hw); + unsigned long flags; + u32 val; + + if (index > 1) + return -EINVAL; + + spin_lock_irqsave(&rtc->lock, flags); + val = readl(rtc->base + SUN6I_LOSC_CTRL); + val &= ~SUN6I_LOSC_CTRL_EXT_OSC; + val |= SUN6I_LOSC_CTRL_KEY; + val |= index ? SUN6I_LOSC_CTRL_EXT_OSC : 0; + writel(val, rtc->base + SUN6I_LOSC_CTRL); + spin_unlock_irqrestore(&rtc->lock, flags); + + return 0; +} + +static const struct clk_ops sun6i_rtc_osc_ops = { + .recalc_rate = sun6i_rtc_osc_recalc_rate, + + .get_parent = sun6i_rtc_osc_get_parent, + .set_parent = sun6i_rtc_osc_set_parent, }; +static void __init sun6i_rtc_clk_init(struct device_node *node) +{ + struct clk_hw_onecell_data *clk_data; + struct sun6i_rtc_dev *rtc; + struct clk_init_data init = { + .ops = &sun6i_rtc_osc_ops, + }; + const char *parents[2]; + + rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return; + spin_lock_init(&rtc->lock); + + clk_data = kzalloc(sizeof(*clk_data) + sizeof(*clk_data->hws), + GFP_KERNEL); + if (!clk_data) + return; + spin_lock_init(&rtc->lock); + + rtc->base = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(rtc->base)) { + pr_crit("Can't map RTC registers"); + return; + } + + /* Switch to the external, more precise, oscillator */ + writel(SUN6I_LOSC_CTRL_KEY | SUN6I_LOSC_CTRL_EXT_OSC, + rtc->base + SUN6I_LOSC_CTRL); + + /* Yes, I know, this is ugly. */ + sun6i_rtc = rtc; + + /* Deal with old DTs */ + if (!of_get_property(node, "clocks", NULL)) + 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; + } + + 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; + 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; + } + + clk_data->num = 1; + clk_data->hws[0] = &rtc->hw; + of_clk_add_hw_provider(node, of_clk_hw_onecell_get, clk_data); +} +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; + irqreturn_t ret = IRQ_NONE; u32 val; + spin_lock(&chip->lock); val = readl(chip->base + SUN6I_ALRM_IRQ_STA); if (val & SUN6I_ALRM_IRQ_STA_CNT_IRQ_PEND) { @@ -129,10 +265,11 @@ static irqreturn_t sun6i_rtc_alarmirq(int irq, void *id) rtc_update_irq(chip->rtc, 1, RTC_AF | RTC_IRQF); - return IRQ_HANDLED; + ret = IRQ_HANDLED; } + spin_unlock(&chip->lock); - return IRQ_NONE; + return ret; } static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip) @@ -140,6 +277,7 @@ static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip) u32 alrm_val = 0; u32 alrm_irq_val = 0; u32 alrm_wake_val = 0; + unsigned long flags; if (to) { alrm_val = SUN6I_ALRM_EN_CNT_EN; @@ -150,9 +288,11 @@ static void sun6i_rtc_setaie(int to, struct sun6i_rtc_dev *chip) chip->base + SUN6I_ALRM_IRQ_STA); } + spin_lock_irqsave(&chip->lock, flags); writel(alrm_val, chip->base + SUN6I_ALRM_EN); writel(alrm_irq_val, chip->base + SUN6I_ALRM_IRQ_EN); writel(alrm_wake_val, chip->base + SUN6I_ALARM_CONFIG); + spin_unlock_irqrestore(&chip->lock, flags); } static int sun6i_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) @@ -191,11 +331,15 @@ static int sun6i_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) static int sun6i_rtc_getalarm(struct device *dev, struct rtc_wkalrm *wkalrm) { struct sun6i_rtc_dev *chip = dev_get_drvdata(dev); + unsigned long flags; u32 alrm_st; u32 alrm_en; + spin_lock_irqsave(&chip->lock, flags); alrm_en = readl(chip->base + SUN6I_ALRM_IRQ_EN); alrm_st = readl(chip->base + SUN6I_ALRM_IRQ_STA); + spin_unlock_irqrestore(&chip->lock, flags); + wkalrm->enabled = !!(alrm_en & SUN6I_ALRM_EN_CNT_EN); wkalrm->pending = !!(alrm_st & SUN6I_ALRM_EN_CNT_EN); rtc_time_to_tm(chip->alarm, &wkalrm->time); @@ -349,22 +493,15 @@ 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"); @@ -404,8 +541,10 @@ static int sun6i_rtc_probe(struct platform_device *pdev) /* disable alarm wakeup */ writel(0, chip->base + SUN6I_ALARM_CONFIG); - chip->rtc = rtc_device_register("rtc-sun6i", &pdev->dev, - &sun6i_rtc_ops, THIS_MODULE); + clk_prepare_enable(chip->losc); + + chip->rtc = devm_rtc_device_register(&pdev->dev, "rtc-sun6i", + &sun6i_rtc_ops, THIS_MODULE); if (IS_ERR(chip->rtc)) { dev_err(&pdev->dev, "unable to register device\n"); return PTR_ERR(chip->rtc); @@ -416,15 +555,6 @@ static int sun6i_rtc_probe(struct platform_device *pdev) return 0; } -static int sun6i_rtc_remove(struct platform_device *pdev) -{ - struct sun6i_rtc_dev *chip = platform_get_drvdata(pdev); - - rtc_device_unregister(chip->rtc); - - return 0; -} - static const struct of_device_id sun6i_rtc_dt_ids[] = { { .compatible = "allwinner,sun6i-a31-rtc" }, { /* sentinel */ }, @@ -433,15 +563,9 @@ MODULE_DEVICE_TABLE(of, sun6i_rtc_dt_ids); static struct platform_driver sun6i_rtc_driver = { .probe = sun6i_rtc_probe, - .remove = sun6i_rtc_remove, .driver = { .name = "sun6i-rtc", .of_match_table = sun6i_rtc_dt_ids, }, }; - -module_platform_driver(sun6i_rtc_driver); - -MODULE_DESCRIPTION("sun6i RTC driver"); -MODULE_AUTHOR("Chen-Yu Tsai <wens@csie.org>"); -MODULE_LICENSE("GPL"); +builtin_platform_driver(sun6i_rtc_driver); |