lkml.org 
[lkml]   [2015]   [Mar]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [rtc-linux] [PATCH 2/2] rtc: mediatek: Add MT63xx RTC driver
    Hi Eddie,

    On Fri, Mar 13, 2015 at 06:29:23PM +0800, Eddie Huang wrote:
    > > regmap_read() and regmap_write() can return errors. There is no
    > > checking for this.
    > >
    >
    > I encounter some trouble when I add code to check return value of
    > regmap_read and regmap_write. Every RTC register access through regmap,
    > and there are many register read/write in this driver. If I check every
    > return value, the driver will become ugly. I try to make this driver
    > clean using following macro.
    >
    > static int __rtc_read(struct mt6397_rtc *rtc, u32 offset, u32 *data)
    > {
    > u32 addr = rtc->addr_base + offset;
    >
    > if (offset < rtc->addr_range)
    > return regmap_read(rtc->regmap, addr, data);
    >
    > return -EINVAL;
    > }
    >
    > #define rtc_read(ret, rtc, offset, data) \
    > ({ \
    > ret = __rtc_read(rtc, offset, data); \
    > if (ret < 0) \
    > goto rtc_exit; \
    > }) \

    Hiding a goto (or return) in a macro is a very bad idea.

    what you can do is

    ret |= regmap_read(rtc->regmap, RTC_TC_SEC, &tm->tm_sec);
    ret |= regmap_read(rtc->regmap, RTC_TC_MIN, &tm->tm_min);

    if (ret)
    return -EIO;

    (Don't return ret in this case though as it might contain different
    error codes orred together)

    Another possibilty at least for contiguous registers would be
    regmap_bulk_read().

    Sascha

    --
    Pengutronix e.K. | |
    Industrial Linux Solutions | http://www.pengutronix.de/ |
    Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
    Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |


    \
     
     \ /
      Last update: 2015-03-13 12:01    [W:4.804 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site