diff --git a/drivers/rtc/rtc-pcf85063.c b/drivers/rtc/rtc-pcf85063.c index a3af86456ccf..32952e73f2f1 100644 --- a/drivers/rtc/rtc-pcf85063.c +++ b/drivers/rtc/rtc-pcf85063.c @@ -44,6 +44,7 @@ #define PCF85063_REG_CTRL2 0x01 #define PCF85063_CTRL2_AF BIT(6) #define PCF85063_CTRL2_AIE BIT(7) +#define PCF85063_CTRL2_TF BIT(3) #define PCF85063_REG_OFFSET 0x02 #define PCF85063_OFFSET_SIGN_BIT 6 /* 2's complement sign bit */ @@ -63,6 +64,14 @@ #define PCF85063_REG_ALM_S 0x0b #define PCF85063_AEN BIT(7) +#define PCF85063_REG_TIMER_VALUE 0x10 +#define PCF85063_REG_TIMER_MODE 0x11 +#define PCF85063_TIMER_MODE_TI_TP BIT(0) +#define PCF85063_TIMER_MODE_TIE BIT(1) +#define PCF85063_TIMER_MODE_TE BIT(2) +#define PCF85063_TIMER_MODE_TCF_MASK GENMASK(4, 3) +#define PCF85063_TIMER_MODE_TCF_1HZ (2 << 3) + struct pcf85063_config { struct regmap_config regmap; unsigned has_alarms:1; @@ -188,20 +197,75 @@ static int pcf85063_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) return 0; } +/* + * The chip has no dedicated 1 Hz update interrupt. Drive the countdown timer + * at 1 Hz to emulate it, so the RTC core can offload UIE to the hardware + * instead of polling. A free-running timer is left untouched to preserve its + * phase across the per-second re-arming done by the core. + */ +static int pcf85063_set_timer_1hz(struct pcf85063 *pcf85063, bool enable) +{ + unsigned int mask = PCF85063_TIMER_MODE_TCF_MASK | + PCF85063_TIMER_MODE_TIE | + PCF85063_TIMER_MODE_TI_TP | + PCF85063_TIMER_MODE_TE; + unsigned int mode = 0; + unsigned int cur; + int ret; + + if (enable) + mode = PCF85063_TIMER_MODE_TCF_1HZ | PCF85063_TIMER_MODE_TIE | + PCF85063_TIMER_MODE_TI_TP | PCF85063_TIMER_MODE_TE; + + ret = regmap_read(pcf85063->regmap, PCF85063_REG_TIMER_MODE, &cur); + if (ret) + return ret; + + if ((cur & mask) == mode) + return 0; + + /* Stop the counter before changing its reload value. */ + ret = regmap_update_bits(pcf85063->regmap, PCF85063_REG_TIMER_MODE, + PCF85063_TIMER_MODE_TE, 0); + if (ret) + return ret; + + if (enable) { + ret = regmap_write(pcf85063->regmap, PCF85063_REG_TIMER_VALUE, 1); + if (ret) + return ret; + + /* Clear TF but preserve AF */ + ret = regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, + PCF85063_CTRL2_TF | PCF85063_CTRL2_AF, PCF85063_CTRL2_AF); + if (ret) + return ret; + } + + return regmap_update_bits(pcf85063->regmap, PCF85063_REG_TIMER_MODE, + mask, mode); +} + static int pcf85063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct pcf85063 *pcf85063 = dev_get_drvdata(dev); u8 buf[5]; int ret; + ret = pcf85063_set_timer_1hz(pcf85063, pcf85063->rtc->uie_rtctimer.enabled); + if (ret) + return ret; + buf[0] = bin2bcd(alrm->time.tm_sec); buf[1] = bin2bcd(alrm->time.tm_min); buf[2] = bin2bcd(alrm->time.tm_hour); buf[3] = bin2bcd(alrm->time.tm_mday); buf[4] = PCF85063_AEN; /* Do not match on week day */ + /* Preserve TF */ ret = regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF, 0); + PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF, + PCF85063_CTRL2_TF); if (ret) return ret; @@ -211,23 +275,33 @@ static int pcf85063_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) return ret; return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF, - alrm->enabled ? PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF : PCF85063_CTRL2_AF); + PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF, + pcf85063->rtc->aie_timer.enabled ? + PCF85063_CTRL2_AIE | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF : + PCF85063_CTRL2_AF | PCF85063_CTRL2_TF); } static int pcf85063_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct pcf85063 *pcf85063 = dev_get_drvdata(dev); + int ret; + + ret = pcf85063_set_timer_1hz(pcf85063, pcf85063->rtc->uie_rtctimer.enabled); + if (ret) + return ret; return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_CTRL2_AIE, - enabled ? PCF85063_CTRL2_AIE : 0); + PCF85063_CTRL2_AIE | PCF85063_CTRL2_TF, + pcf85063->rtc->aie_timer.enabled ? + PCF85063_CTRL2_AIE | PCF85063_CTRL2_TF : PCF85063_CTRL2_TF); } static irqreturn_t pcf85063_rtc_handle_irq(int irq, void *dev_id) { struct pcf85063 *pcf85063 = dev_id; + unsigned long events = RTC_IRQF; + irqreturn_t ret = IRQ_NONE; unsigned int val; int err; @@ -236,13 +310,33 @@ static irqreturn_t pcf85063_rtc_handle_irq(int irq, void *dev_id) return IRQ_NONE; if (val & PCF85063_CTRL2_AF) { - rtc_update_irq(pcf85063->rtc, 1, RTC_IRQF | RTC_AF); - regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_CTRL2_AF, 0); - return IRQ_HANDLED; + events |= RTC_AF; + val &= ~PCF85063_CTRL2_AF; + ret = IRQ_HANDLED; + } else { + /* Preserve AF if it comes after the above regmap_read() */ + val |= PCF85063_CTRL2_AF; } - return IRQ_NONE; + if (val & PCF85063_CTRL2_TF) { + events |= RTC_UF; + val &= ~PCF85063_CTRL2_TF; + ret = IRQ_HANDLED; + } else { + /* + * While not documented, TF demonstrates the same + * write-1-to-preserve semantics as AF in real HW + */ + val |= PCF85063_CTRL2_TF; + } + + if (ret == IRQ_HANDLED) { + regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, + PCF85063_CTRL2_AF | PCF85063_CTRL2_TF, val); + rtc_update_irq(pcf85063->rtc, 1, events); + } + + return ret; } static int pcf85063_read_offset(struct device *dev, long *offset) @@ -431,8 +525,8 @@ static int pcf85063_clkout_set_rate(struct clk_hw *hw, unsigned long rate, if (clkout_rates[i] == rate) return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_REG_CLKO_F_MASK | PCF85063_CTRL2_AF, - i | PCF85063_CTRL2_AF); + PCF85063_REG_CLKO_F_MASK | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF, + i | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF); return -EINVAL; } @@ -461,8 +555,8 @@ static int pcf85063_clkout_control(struct clk_hw *hw, bool enable) } return regmap_update_bits(pcf85063->regmap, PCF85063_REG_CTRL2, - PCF85063_REG_CLKO_F_MASK | PCF85063_CTRL2_AF, - buf | PCF85063_CTRL2_AF); + PCF85063_REG_CLKO_F_MASK | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF, + buf | PCF85063_CTRL2_AF | PCF85063_CTRL2_TF); } static int pcf85063_clkout_prepare(struct clk_hw *hw) @@ -609,6 +703,7 @@ static int pcf85063_probe(struct device *dev, struct regmap *regmap, int irq, dev_warn(&pcf85063->rtc->dev, "unable to request IRQ, alarms disabled\n"); } else { + set_bit(RTC_FEATURE_UPDATE_INTERRUPT, pcf85063->rtc->features); set_bit(RTC_FEATURE_ALARM, pcf85063->rtc->features); device_init_wakeup(dev, true); err = dev_pm_set_wake_irq(dev, irq);