From: Mohit Aggarwal maggarwa@codeaurora.org
[ Upstream commit 83220bf38b77a830f8e62ab1a0d0408304f9b966 ]
In order to set time in rtc, need to disable rtc hw before writing into rtc registers.
Also fixes disabling of alarm while setting rtc time.
Signed-off-by: Mohit Aggarwal maggarwa@codeaurora.org Signed-off-by: Alexandre Belloni alexandre.belloni@bootlin.com Signed-off-by: Lee Jones lee.jones@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/rtc/rtc-pm8xxx.c | 49 ++++++++++++++++++++++++++++++++++++----------- 1 file changed, 38 insertions(+), 11 deletions(-)
--- a/drivers/rtc/rtc-pm8xxx.c +++ b/drivers/rtc/rtc-pm8xxx.c @@ -74,16 +74,18 @@ struct pm8xxx_rtc { /* * Steps to write the RTC registers. * 1. Disable alarm if enabled. - * 2. Write 0x00 to LSB. - * 3. Write Byte[1], Byte[2], Byte[3] then Byte[0]. - * 4. Enable alarm if disabled in step 1. + * 2. Disable rtc if enabled. + * 3. Write 0x00 to LSB. + * 4. Write Byte[1], Byte[2], Byte[3] then Byte[0]. + * 5. Enable rtc if disabled in step 2. + * 6. Enable alarm if disabled in step 1. */ static int pm8xxx_rtc_set_time(struct device *dev, struct rtc_time *tm) { int rc, i; unsigned long secs, irq_flags; - u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0; - unsigned int ctrl_reg; + u8 value[NUM_8_BIT_RTC_REGS], alarm_enabled = 0, rtc_disabled = 0; + unsigned int ctrl_reg, rtc_ctrl_reg; struct pm8xxx_rtc *rtc_dd = dev_get_drvdata(dev); const struct pm8xxx_rtc_regs *regs = rtc_dd->regs;
@@ -92,23 +94,38 @@ static int pm8xxx_rtc_set_time(struct de
rtc_tm_to_time(tm, &secs);
+ dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs); + for (i = 0; i < NUM_8_BIT_RTC_REGS; i++) { value[i] = secs & 0xFF; secs >>= 8; }
- dev_dbg(dev, "Seconds value to be written to RTC = %lu\n", secs); - spin_lock_irqsave(&rtc_dd->ctrl_reg_lock, irq_flags);
- rc = regmap_read(rtc_dd->regmap, regs->ctrl, &ctrl_reg); + rc = regmap_read(rtc_dd->regmap, regs->alarm_ctrl, &ctrl_reg); if (rc) goto rtc_rw_fail;
if (ctrl_reg & regs->alarm_en) { alarm_enabled = 1; ctrl_reg &= ~regs->alarm_en; - rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg); + rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg); + if (rc) { + dev_err(dev, "Write to RTC Alarm control register failed\n"); + goto rtc_rw_fail; + } + } + + /* Disable RTC H/w before writing on RTC register */ + rc = regmap_read(rtc_dd->regmap, regs->ctrl, &rtc_ctrl_reg); + if (rc) + goto rtc_rw_fail; + + if (rtc_ctrl_reg & PM8xxx_RTC_ENABLE) { + rtc_disabled = 1; + rtc_ctrl_reg &= ~PM8xxx_RTC_ENABLE; + rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg); if (rc) { dev_err(dev, "Write to RTC control register failed\n"); goto rtc_rw_fail; @@ -137,11 +154,21 @@ static int pm8xxx_rtc_set_time(struct de goto rtc_rw_fail; }
+ /* Enable RTC H/w after writing on RTC register */ + if (rtc_disabled) { + rtc_ctrl_reg |= PM8xxx_RTC_ENABLE; + rc = regmap_write(rtc_dd->regmap, regs->ctrl, rtc_ctrl_reg); + if (rc) { + dev_err(dev, "Write to RTC control register failed\n"); + goto rtc_rw_fail; + } + } + if (alarm_enabled) { ctrl_reg |= regs->alarm_en; - rc = regmap_write(rtc_dd->regmap, regs->ctrl, ctrl_reg); + rc = regmap_write(rtc_dd->regmap, regs->alarm_ctrl, ctrl_reg); if (rc) { - dev_err(dev, "Write to RTC control register failed\n"); + dev_err(dev, "Write to RTC Alarm control register failed\n"); goto rtc_rw_fail; } }