Re: [PATCH V3 3/3] rtc: omap: Support regulator supply for RTC
From: Nishanth Menon <nm@ti.com>
Date: 2014-10-24 13:26:43
Also in:
linux-arm-kernel, linux-omap
On 10/23/2014 11:53 PM, Lokesh Vutla wrote:
On some Soc's RTC is powered by an external power regulator.
SoC ? -> could you rephrase this to indicate "certain SoCs such as DRA7, RTC is an independent voltage domain of it's own and on platforms such as DRA7-evm, this may be supplied by individual regulator on it's own.
e.g. RTC on DRA7 SoC. Make the OMAP RTC driver support a power regulator.
Question ofcourse is what voltage would you like that regulator to be at? As you are aware, certain LDOs and SMPS can drive varying voltage and just enable/disable would do just the default voltage of the SMPS/LDO, right? OR am i missing something here?
quoted hunk ↗ jump to hunk
Signed-off-by: Lokesh Vutla <redacted> --- Documentation/devicetree/bindings/rtc/rtc-omap.txt | 3 +++ drivers/rtc/rtc-omap.c | 24 ++++++++++++++++++++++ 2 files changed, 27 insertions(+)diff --git a/Documentation/devicetree/bindings/rtc/rtc-omap.txt b/Documentation/devicetree/bindings/rtc/rtc-omap.txt index 750efd4..e7ad12b 100644 --- a/Documentation/devicetree/bindings/rtc/rtc-omap.txt +++ b/Documentation/devicetree/bindings/rtc/rtc-omap.txt@@ -15,6 +15,8 @@ Required properties: Optional properties: - ti,system-power-controller: whether the rtc is controlling the system power through pmic_power_en +Optional Properties:
^^ already commented on..
+- vrtc-supply: phandle to the regulator device tree node if needed
"phandle to supply regulator" ? since it is optional, "if needed" is redundant?
quoted hunk ↗ jump to hunk
Example:@@ -25,4 +27,5 @@ rtc@1c23000 { 19>; interrupt-parent = <&intc>; ti,system-power-controller; + vrtc-supply = <&ldo9_reg>; };diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c index d9bb5e7..61fe630 100644 --- a/drivers/rtc/rtc-omap.c +++ b/drivers/rtc/rtc-omap.c@@ -25,6 +25,7 @@ #include <linux/of_device.h> #include <linux/pm_runtime.h> #include <linux/io.h> +#include <linux/regulator/consumer.h> /* * The OMAP RTC is a year/month/day/hours/minutes/seconds BCD clock@@ -134,6 +135,7 @@ struct omap_rtc { u8 interrupts_reg; bool is_pmic_controller; const struct omap_rtc_device_type *type; + struct regulator *supply; }; static inline u8 rtc_read(struct omap_rtc *rtc, unsigned int reg)@@ -516,6 +518,22 @@ static int omap_rtc_probe(struct platform_device *pdev) platform_set_drvdata(pdev, rtc); + rtc->supply = devm_regulator_get_optional(&pdev->dev, "vrtc"); + if (IS_ERR(rtc->supply)) { + if (PTR_ERR(rtc->supply) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + rtc->supply = NULL; + } + + if (rtc->supply) { + ret = regulator_enable(rtc->supply); + if (ret) { + dev_err(&pdev->dev, "regulator enable failed\n");
would be nice to print the result as well - since it helps debug from log a little easier. -- Regards, Nishanth Menon