Instead of hard-coded values and ifdefs, store the year offset in the
platform_data struct.
Tested-by: Daniel Palmer <daniel@0x0f.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
---
I tested this for regressions using qemu-system-sparc64.
Also, Daniel tested the RTC functionality on his MVME147 system.
---
arch/sparc/kernel/time_32.c | 1 +
arch/sparc/kernel/time_64.c | 1 +
drivers/rtc/rtc-m48t59.c | 26 ++++----------------------
include/linux/rtc/m48t59.h | 3 +++
4 files changed, 9 insertions(+), 22 deletions(-)
diff --git a/arch/sparc/kernel/time_32.c b/arch/sparc/kernel/time_32.c
index 08bbdc458596..578fd0d49f30 100644
--- a/arch/sparc/kernel/time_32.c
+++ b/arch/sparc/kernel/time_32.c
@@ -255,6 +255,7 @@ static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
static struct m48t59_plat_data m48t59_data = {
.read_byte = mostek_read_byte,
.write_byte = mostek_write_byte,
+ .yy_offset = 68,
};
/* resource is set at runtime */
diff --git a/arch/sparc/kernel/time_64.c b/arch/sparc/kernel/time_64.c
index 60f1c8cc5363..b32f27f929d1 100644
--- a/arch/sparc/kernel/time_64.c
+++ b/arch/sparc/kernel/time_64.c
@@ -544,6 +544,7 @@ static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
static struct m48t59_plat_data m48t59_data = {
.read_byte = mostek_read_byte,
.write_byte = mostek_write_byte,
+ .yy_offset = 68,
};
static struct platform_device m48t59_rtc = {
diff --git a/drivers/rtc/rtc-m48t59.c b/drivers/rtc/rtc-m48t59.c
index f0f6b9b6daec..4c339fb45b5c 100644
--- a/drivers/rtc/rtc-m48t59.c
+++ b/drivers/rtc/rtc-m48t59.c
@@ -71,7 +71,7 @@ static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
/* Issue the READ command */
M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
- tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
+ tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR)) + pdata->yy_offset;
/* tm_mon is 0-11 */
tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
tm->tm_mday = bcd2bin(M48T59_READ(M48T59_MDAY));
@@ -82,10 +82,6 @@ static int m48t59_rtc_read_time(struct device *dev, struct rtc_time *tm)
dev_dbg(dev, "Century bit is enabled\n");
tm->tm_year += 100; /* one century */
}
-#ifdef CONFIG_SPARC
- /* Sun SPARC machines count years since 1968 */
- tm->tm_year += 68;
-#endif
tm->tm_wday = bcd2bin(val & 0x07);
tm->tm_hour = bcd2bin(M48T59_READ(M48T59_HOUR) & 0x3F);
@@ -106,12 +102,7 @@ static int m48t59_rtc_set_time(struct device *dev, struct rtc_time *tm)
struct m48t59_private *m48t59 = dev_get_drvdata(dev);
unsigned long flags;
u8 val = 0;
- int year = tm->tm_year;
-
-#ifdef CONFIG_SPARC
- /* Sun SPARC machines count years since 1968 */
- year -= 68;
-#endif
+ int year = tm->tm_year - pdata->yy_offset;
dev_dbg(dev, "RTC set time %04d-%02d-%02d %02d/%02d/%02d\n",
year + 1900, tm->tm_mon, tm->tm_mday,
@@ -162,11 +153,7 @@ static int m48t59_rtc_readalarm(struct device *dev, struct rtc_wkalrm *alrm)
/* Issue the READ command */
M48T59_SET_BITS(M48T59_CNTL_READ, M48T59_CNTL);
- tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR));
-#ifdef CONFIG_SPARC
- /* Sun SPARC machines count years since 1968 */
- tm->tm_year += 68;
-#endif
+ tm->tm_year = bcd2bin(M48T59_READ(M48T59_YEAR)) + pdata->yy_offset;
/* tm_mon is 0-11 */
tm->tm_mon = bcd2bin(M48T59_READ(M48T59_MONTH)) - 1;
@@ -197,12 +184,7 @@ static int m48t59_rtc_setalarm(struct device *dev, struct rtc_wkalrm *alrm)
struct rtc_time *tm = &alrm->time;
u8 mday, hour, min, sec;
unsigned long flags;
- int year = tm->tm_year;
-
-#ifdef CONFIG_SPARC
- /* Sun SPARC machines count years since 1968 */
- year -= 68;
-#endif
+ int year = tm->tm_year - pdata->yy_offset;
/* If no irq, we don't support ALARM */
if (m48t59->irq == NO_IRQ)
diff --git a/include/linux/rtc/m48t59.h b/include/linux/rtc/m48t59.h
index 9465d5405fe2..6ac1eb2cbeac 100644
--- a/include/linux/rtc/m48t59.h
+++ b/include/linux/rtc/m48t59.h
@@ -56,6 +56,9 @@ struct m48t59_plat_data {
void __iomem *ioaddr;
/* offset to RTC registers, automatically set according to the type */
unsigned int offset;
+
+ /* YY digits (in RTC) are offset, i.e. year is 1900 + yy_offset + YY */
+ time64_t yy_offset;
};
#endif /* _LINUX_RTC_M48T59_H_ */
--
2.39.5Hi Finn,
On Tue, Oct 8, 2024 at 12:43 AM Finn Thain <fthain@linux-m68k.org> wrote:
> Instead of hard-coded values and ifdefs, store the year offset in the
> platform_data struct.
>
> Tested-by: Daniel Palmer <daniel@0x0f.com>
> Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Thanks for your patch!
> --- a/include/linux/rtc/m48t59.h
> +++ b/include/linux/rtc/m48t59.h
> @@ -56,6 +56,9 @@ struct m48t59_plat_data {
> void __iomem *ioaddr;
> /* offset to RTC registers, automatically set according to the type */
> unsigned int offset;
> +
> + /* YY digits (in RTC) are offset, i.e. year is 1900 + yy_offset + YY */
> + time64_t yy_offset;
time64_t sounds like overkill to me...
> };
>
> #endif /* _LINUX_RTC_M48T59_H_ */
The rest LGTM.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
On Tue, 8 Oct 2024, Geert Uytterhoeven wrote:
> Hi Finn,
>
> On Tue, Oct 8, 2024 at 12:43 AM Finn Thain <fthain@linux-m68k.org> wrote:
> > Instead of hard-coded values and ifdefs, store the year offset in the
> > platform_data struct.
> >
> > Tested-by: Daniel Palmer <daniel@0x0f.com>
> > Signed-off-by: Finn Thain <fthain@linux-m68k.org>
>
> Thanks for your patch!
>
Thanks for your review.
> > --- a/include/linux/rtc/m48t59.h
> > +++ b/include/linux/rtc/m48t59.h
> > @@ -56,6 +56,9 @@ struct m48t59_plat_data {
> > void __iomem *ioaddr;
> > /* offset to RTC registers, automatically set according to the type */
> > unsigned int offset;
> > +
> > + /* YY digits (in RTC) are offset, i.e. year is 1900 + yy_offset + YY */
> > + time64_t yy_offset;
>
> time64_t sounds like overkill to me...
>
A vestige of an earlier experiment. Sorry about that. I shall send v3.
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