Re: [PATCH 1/4] rtc: mcp795: fix invalid month setting.

From: Alexandre Belloni
Date: Mon Dec 05 2016 - 10:10:06 EST


Hi,

On 05/12/2016 at 14:11:50 +0100, Emil Bartczak wrote :
> The 10 month register was always set to value 0 in the RTC hardware.
> Due to the bug month November or December became February.

All your patches are missing your SoB, see Developer's Certificate of
Origin 1.1 in Documentation/SubmittingPatches

> ---
> drivers/rtc/rtc-mcp795.c | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/rtc/rtc-mcp795.c b/drivers/rtc/rtc-mcp795.c
> index 4021fd0..266328b 100644
> --- a/drivers/rtc/rtc-mcp795.c
> +++ b/drivers/rtc/rtc-mcp795.c
> @@ -29,7 +29,7 @@
> #define MCP795_EEWREN 0x06
> #define MCP795_SRREAD 0x05
> #define MCP795_SRWRITE 0x01
> -#define MCP795_READ 0x13
> +#define MCP795_READ 0x13

Unrelated change

> #define MCP795_WRITE 0x12
> #define MCP795_UNLOCK 0x14
> #define MCP795_IDWRITE 0x32
> @@ -39,6 +39,7 @@
>
> #define MCP795_ST_BIT 0x80
> #define MCP795_24_BIT 0x40
> +#define MCP795_LP_BIT 0x20
>
> static int mcp795_rtcc_read(struct device *dev, u8 addr, u8 *buf, u8 count)
> {
> @@ -108,7 +109,8 @@ static int mcp795_set_time(struct device *dev, struct rtc_time *tim)
> data[1] = (data[1] & 0x80) | ((tim->tm_min / 10) << 4) | (tim->tm_min % 10);
> data[2] = ((tim->tm_hour / 10) << 4) | (tim->tm_hour % 10);
> data[4] = ((tim->tm_mday / 10) << 4) | ((tim->tm_mday) % 10);
> - data[5] = (data[5] & 0x10) | (tim->tm_mon / 10) | (tim->tm_mon % 10);
> + data[5] = (data[5] & MCP795_LP_BIT) |

You changed 0x10 in MCP795_LP_BIT which you defined as 0x20, is that
right?

This is also an unrelated change.

> + ((tim->tm_mon / 10) << 4) | (tim->tm_mon % 10);
>
> if (tim->tm_year > 100)
> tim->tm_year -= 100;
> @@ -137,11 +139,11 @@ static int mcp795_read_time(struct device *dev, struct rtc_time *tim)
> if (ret)
> return ret;
>
> - tim->tm_sec = ((data[0] & 0x70) >> 4) * 10 + (data[0] & 0x0f);
> - tim->tm_min = ((data[1] & 0x70) >> 4) * 10 + (data[1] & 0x0f);
> + tim->tm_sec = ((data[0] & 0x70) >> 4) * 10 + (data[0] & 0x0f);
> + tim->tm_min = ((data[1] & 0x70) >> 4) * 10 + (data[1] & 0x0f);
> tim->tm_hour = ((data[2] & 0x30) >> 4) * 10 + (data[2] & 0x0f);
> tim->tm_mday = ((data[4] & 0x30) >> 4) * 10 + (data[4] & 0x0f);
> - tim->tm_mon = ((data[5] & 0x10) >> 4) * 10 + (data[5] & 0x0f);
> + tim->tm_mon = ((data[5] & 0x10) >> 4) * 10 + (data[5] & 0x0f);

All those whitespace changes are actually confusing. Please do them in a
separate patch or in your last patch.

> tim->tm_year = ((data[6] & 0xf0) >> 4) * 10 + (data[6] & 0x0f) + 100; /* Assume we are in 20xx */
>
> dev_dbg(dev, "Read from mcp795: %04d-%02d-%02d %02d:%02d:%02d\n",
> --
> 2.7.4
>

--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com