[U-Boot] [EXT] Re: [PATCH v5] rtc: pcf2127: Fixed bug with rtc settings and getting error time

Chuanhua Han chuanhua.han at nxp.com
Tue Jul 9 08:52:47 UTC 2019



> -----Original Message-----
> From: Heiko Schocher <hs at denx.de>
> Sent: 2019年7月9日 16:50
> To: Chuanhua Han <chuanhua.han at nxp.com>
> Cc: lukma at denx.de; Prabhakar Kushwaha <prabhakar.kushwaha at nxp.com>;
> Biwen Li <biwen.li at nxp.com>; sjg at chromium.org; u-boot at lists.denx.de
> Subject: [EXT] Re: [PATCH v5] rtc: pcf2127: Fixed bug with rtc settings and
> getting error time
> 
> Caution: EXT Email
> 
> Hello Chuanhua Han,
> 
> Am 08.07.2019 um 05:45 schrieb Chuanhua Han:
> > The previous pcf2127 RTC chip could not read and set the correct time.
> > When reading the data of internal registers, the read address was the
> > value of register plus 1. This is because this chip requires the host
> > to send a stop signal after setting the register address and before
> > reading the register data.
> >
> > This patch sets the register address using dm_i2c_write and reads the
> > register data using the original dm_i2c_xfer in order to generate a
> > stop signal after the register address is set, and fixes the bug of
> > the original read and write time.
> >
> > Signed-off-by: Biwen Li <biwen.li at nxp.com>
> > Signed-off-by: Chuanhua Han <chuanhua.han at nxp.com>
> > Reviewed-by: Lukasz Majewski <lukma at denx.de>
> > ---
> > Changes in v5:
> >       - The modification made by i2c core layer is removed, and the
> > RTC time bug is fixed in pcf2127 driver using dm_i2c_xfer.
> > Changes in v4:
> >       - Replace DM_I2C_CHIP_RD_NO_I2C_SETUP_OFFSET with
> > DM_I2C_CHIP_ADDR_STOP.
> > Changes in v3:
> >       - When the rtc time is obtained, the address of the set register
> > is separated from the read data.
> > Changes in v2:
> >       - Split the original patch into 3 patches
> >       - Add detailed description information for each patch
> >
> >   drivers/rtc/pcf2127.c |   33 ++++++++++++++++++++++++---------
> >   1 files changed, 24 insertions(+), 9 deletions(-)
> 
> Looks good to me now, many thanks!
Thank you very much for your advice!
> 
> Reviewed-by: Heiko Schocher <hs at denx.de>
> 
> bye,
> Heiko
> --
> --
> DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: +49-8142-66989-52   Fax: +49-8142-66989-80   Email: hs at denx.de


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