rtc: omap: Add external clock enabling support

Configure the clock source to external clock if available.
External clock is preferred as it can be ticking during suspend.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
This commit is contained in:
Keerthy 2015-08-18 15:11:16 +05:30 committed by Alexandre Belloni
parent 532409aa1b
commit 399cf0f63f

View file

@ -108,6 +108,7 @@
/* OMAP_RTC_OSC_REG bit fields: */
#define OMAP_RTC_OSC_32KCLK_EN BIT(6)
#define OMAP_RTC_OSC_SEL_32KCLK_SRC BIT(3)
/* OMAP_RTC_IRQWAKEEN bit fields: */
#define OMAP_RTC_IRQWAKEEN_ALARM_WAKEEN BIT(1)
@ -138,6 +139,7 @@ struct omap_rtc {
int irq_timer;
u8 interrupts_reg;
bool is_pmic_controller;
bool has_ext_clk;
const struct omap_rtc_device_type *type;
};
@ -555,7 +557,11 @@ static int omap_rtc_probe(struct platform_device *pdev)
if (rtc->irq_alarm <= 0)
return -ENOENT;
rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
rtc->clk = devm_clk_get(&pdev->dev, "ext-clk");
if (!IS_ERR(rtc->clk))
rtc->has_ext_clk = true;
else
rtc->clk = devm_clk_get(&pdev->dev, "int-clk");
if (!IS_ERR(rtc->clk))
clk_prepare_enable(rtc->clk);
@ -634,6 +640,16 @@ static int omap_rtc_probe(struct platform_device *pdev)
if (reg != new_ctrl)
rtc_write(rtc, OMAP_RTC_CTRL_REG, new_ctrl);
/*
* If we have the external clock then switch to it so we can keep
* ticking across suspend.
*/
if (rtc->has_ext_clk) {
reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
rtc_write(rtc, OMAP_RTC_OSC_REG,
reg | OMAP_RTC_OSC_SEL_32KCLK_SRC);
}
rtc->type->lock(rtc);
device_init_wakeup(&pdev->dev, true);
@ -679,6 +695,7 @@ static int omap_rtc_probe(struct platform_device *pdev)
static int __exit omap_rtc_remove(struct platform_device *pdev)
{
struct omap_rtc *rtc = platform_get_drvdata(pdev);
u8 reg;
if (pm_power_off == omap_rtc_power_off &&
omap_rtc_power_off_rtc == rtc) {
@ -695,6 +712,12 @@ static int __exit omap_rtc_remove(struct platform_device *pdev)
/* leave rtc running, but disable irqs */
rtc_write(rtc, OMAP_RTC_INTERRUPTS_REG, 0);
if (rtc->has_ext_clk) {
reg = rtc_read(rtc, OMAP_RTC_OSC_REG);
reg &= ~OMAP_RTC_OSC_SEL_32KCLK_SRC;
rtc_write(rtc, OMAP_RTC_OSC_REG, reg);
}
rtc->type->lock(rtc);
/* Disable the clock/module */