Thread (13 messages) 13 messages, 4 authors, 2020-03-09

Re: [PATCH v8 4/5] rtc: mt6397: Add support for the MediaTek MT6358 RTC

From: Nicolas Boichat <hidden>
Date: 2020-03-04 13:00:09
Also in: linux-devicetree, linux-mediatek, linux-rtc, lkml

Hi,

On Mon, Feb 17, 2020 at 11:52 AM Ran Bi [off-list ref] wrote:
On Tue, 2020-02-04 at 00:50 +0800, Yingjoe Chen wrote:
quoted
quoted
diff --git a/include/linux/mfd/mt6397/rtc.h b/include/linux/mfd/mt6397/rtc.h
index f84b916..fffe34a 100644
--- a/include/linux/mfd/mt6397/rtc.h
+++ b/include/linux/mfd/mt6397/rtc.h
@@ -18,7 +18,8 @@
 #define RTC_BBPU_CBUSY         BIT(6)
 #define RTC_BBPU_KEY            (0x43 << 8)

-#define RTC_WRTGR              0x003c
+#define RTC_WRTGR_MT6358       0x3a
+#define RTC_WRTGR_MT6397       0x3c

 #define RTC_IRQ_STA            0x0002
 #define RTC_IRQ_STA_AL         BIT(0)
@@ -57,6 +58,10 @@
 #define MTK_RTC_POLL_DELAY_US  10
 #define MTK_RTC_POLL_TIMEOUT   (jiffies_to_usecs(HZ))

+struct mtk_rtc_data {
+   u32                     wrtgr;
+};
+
 struct mt6397_rtc {
    struct device           *dev;
    struct rtc_device       *rtc_dev;
@@ -66,6 +71,15 @@ struct mt6397_rtc {
    struct regmap           *regmap;
    int                     irq;
    u32                     addr_base;
+   const struct mtk_rtc_data *data;
+};
+
+static const struct mtk_rtc_data mt6358_rtc_data = {
+   .wrtgr = RTC_WRTGR_MT6358,
+};
+
+static const struct mtk_rtc_data mt6397_rtc_data = {
+   .wrtgr = RTC_WRTGR_MT6397,
 };
Hi,

Putting these in header file doesn't looks right to me.
Who need this? can you move them back to rtc-mt6397.c?
Joe.C
This could also effect kernel/drivers/power/reset/mt6323-poweroff.c
which using same region of RTC registers.
There are 2 ways of modification:
1. kernel/drivers/rtc/rtc-mt6397.c implement do_pwroff function and
export to mt6323-poweroff.c
2. Just modify mt6323-poweroff.c file to compatible this patch. I mean
using RTC_WRTGR_MT6397 to replace RTC_WRTGR. Or modify mt6323-poweroff.c
like rtc-mt6397.c
Oh, I see, so basically both rtc-mt6397.c and mt6323-poweroff.c need
to know at what offset RTC_WRTGR actually is. Correct?

Is there any plan to have mt6323-poweroff.c support any of the other
PMICs (not just MT6323?)?

a. If not, I'd just add:
#define RTC_WRTGR_MT6323 RTC_WRTGR_MT6397
in rtc.h, for added clarity, use that in mt6323-poweroff.c
(s/RTC_WRTGR/RTC_WRTGR_MT6323/), and be done with it.

Actually, even if there's a plan, you can go ahead with this simpler
solution for now, and fix later when the issue comes up.

b. If you ever want to support multiple PMICs with mt6323-poweroff.c,
you'd need that offset for 2 different sub-devices under the same mfd,
so the matching logic belongs in the main mfd device, not in
rtc/poweroff driver.

So I'd move the matching logic in drivers/mfd/mt6397-core.c, and add
rtc_wrtgr offset (or a full _data structure) to `struct mt6397_chip`,
or, probably better, add a IORESOURCE_REG to the matching resources to
specify the offset (that's what drivers/mfd/88pm860x-core.c seems to
be doing, for example).

And then mt6323-poweroff.c should probably be renamed to mt6397-poweroff.c.

(actually, looking at this, I'm even questioning if mt6323-poweroff.c
should even exist, and if you should just fold it into rtc-mt6397.c?
Since they use the same registers?)

Hope this makes sense?

Best,

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help