[PATCH V4 4/7] i2c: qup: Transfer each i2c_msg in i2c_msgs without a stop bit

Sricharan sricharan at codeaurora.org
Tue Jul 21 01:09:46 PDT 2015


Hi Ivan,

> -----Original Message-----
> From: Ivan T. Ivanov [mailto:iivanov at mm-sol.com]
> Sent: Monday, July 20, 2015 4:53 PM
> To: Sricharan R
> Cc: devicetree at vger.kernel.org; linux-arm-msm at vger.kernel.org;
> galak at codeaurora.org; linux-kernel at vger.kernel.org; linux-
> i2c at vger.kernel.org; agross at codeaurora.org; dmaengine at vger.kernel.org;
> linux-arm-kernel at lists.infradead.org
> Subject: Re: [PATCH V4 4/7] i2c: qup: Transfer each i2c_msg in i2c_msgs
> without a stop bit
> 
> 
> Hi,
> 
> On Thu, 2015-07-09 at 08:55 +0530, Sricharan R wrote:
> 
> <snip>
> 
> >  #define ONE_BYTE                       0x1
> > +#define QUP_I2C_MX_CONFIG_DURING_RUN   BIT(31)
> >
> >  struct qup_i2c_block {
> >         int     count;
> > @@ -121,6 +122,7 @@ struct qup_i2c_block {
> >         int     rx_tag_len;
> >         int     data_len;
> >         u8      tags[6];
> > +       int     config_run;
> 
> This is not directly related to "block" control logic, right?
> Could it made part of qup_i2c_dev structure?
> 
   Yes, can move it there.

> >  };
> >
> >  struct qup_i2c_dev {
> > @@ -152,6 +154,10 @@ struct qup_i2c_dev {
> >
> >         int (*qup_i2c_write_one)(struct qup_i2c_dev *qup,
> >                                         struct i2c_msg *msg);
> > +       /* Current i2c_msg in i2c_msgs */
> > +       int     cmsg;
> > +       /* total num of i2c_msgs */
> > +       int     num;
> 
> I think it will be simpler with just "bool is_last" evaluated in main xfer loop.
  
   Hmm ok. Will change it that way. Set it one place and use it other places.
> 
> <snip>
> 
> >
> > @@ -374,6 +383,9 @@ static void qup_i2c_get_blk_data(struct
> qup_i2c_dev *qup,
> >         /* There are 2 tag bytes that are read in to fifo for every block */
> >         if (msg->flags & I2C_M_RD)
> >                 qup->blk.rx_tag_len = qup->blk.count * 2;
> > +
> > +       if (qup->cmsg)
> > +               qup->blk.config_run = QUP_I2C_MX_CONFIG_DURING_RUN;
> 
> This could be moved to qup_i2c_xfer_v2() to avoid repeatedly setting it.
     Ok, correct.

Regards,
 Sricharan




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