From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ray Jui Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode Date: Thu, 9 May 2019 10:10:45 -0700 Message-ID: <3f3938ea-3710-99ef-4f35-433cb7156e05@broadcom.com> References: <1557375708-14830-1-git-send-email-rayagonda.kokatanur@broadcom.com> <508d6d50-29a6-dfa7-8e25-b64fa2cbbb8a@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Rayagonda Kokatanur Cc: Wolfram Sang , Rob Herring , Mark Rutland , linux-i2c@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Michael Cheng , Srinath Mannam List-Id: linux-i2c@vger.kernel.org On 5/9/2019 10:03 AM, Rayagonda Kokatanur wrote: > No change,  it's just duplicate, please ignore.  > > I am not able to find my patch over network , I tried sending second > time by setting plain text mode,  but still it's not visible. > I can see your patch from the linux-i2c mailing list: https://patchwork.ozlabs.org/project/linux-i2c/list/ > Best regards  > Rayagonda > > On Thu, May 9, 2019, 9:58 PM Ray Jui wrote: > > Why is the email sent twice? What has changed? > > On 5/8/2019 9:21 PM, Rayagonda Kokatanur wrote: > > Add multiple byte read-write support for slave mode. > > > > Signed-off-by: Rayagonda Kokatanur > > > > Signed-off-by: Srinath Mannam > > > --- > >  drivers/i2c/busses/i2c-bcm-iproc.c | 117 > +++++++++++++++++-------------------- > >  1 file changed, 53 insertions(+), 64 deletions(-) > > > > diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c > b/drivers/i2c/busses/i2c-bcm-iproc.c > > index a845b8d..2c7f145 100644 > > --- a/drivers/i2c/busses/i2c-bcm-iproc.c > > +++ b/drivers/i2c/busses/i2c-bcm-iproc.c > > @@ -165,12 +165,6 @@ enum i2c_slave_read_status { > >       I2C_SLAVE_RX_END, > >  }; > >  > > -enum i2c_slave_xfer_dir { > > -     I2C_SLAVE_DIR_READ = 0, > > -     I2C_SLAVE_DIR_WRITE, > > -     I2C_SLAVE_DIR_NONE, > > -}; > > - > >  enum bus_speed_index { > >       I2C_SPD_100K = 0, > >       I2C_SPD_400K, > > @@ -203,7 +197,6 @@ struct bcm_iproc_i2c_dev { > >       struct i2c_msg *msg; > >  > >       struct i2c_client *slave; > > -     enum i2c_slave_xfer_dir xfer_dir; > >  > >       /* bytes that have been transferred */ > >       unsigned int tx_bytes; > > @@ -219,7 +212,8 @@ struct bcm_iproc_i2c_dev { > >               | BIT(IS_M_RX_THLD_SHIFT)) > >  > >  #define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\ > > -             | BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)) > > +             | BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\ > > +             | BIT(IS_S_TX_UNDERRUN_SHIFT)) > >  > >  static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave); > >  static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave); > > @@ -297,15 +291,11 @@ static void bcm_iproc_i2c_slave_init( > >       /* clear all pending slave interrupts */ > >       iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE); > >  > > -     /* Enable interrupt register for any READ event */ > > -     val = BIT(IE_S_RD_EVENT_SHIFT); > >       /* Enable interrupt register to indicate a valid byte in > receive fifo */ > > -     val |= BIT(IE_S_RX_EVENT_SHIFT); > > +     val = BIT(IE_S_RX_EVENT_SHIFT); > >       /* Enable interrupt register for the Slave BUSY command */ > >       val |= BIT(IE_S_START_BUSY_SHIFT); > >       iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); > > - > > -     iproc_i2c->xfer_dir = I2C_SLAVE_DIR_NONE; > >  } > >  > >  static void bcm_iproc_i2c_check_slave_status( > > @@ -314,8 +304,11 @@ static void bcm_iproc_i2c_check_slave_status( > >       u32 val; > >  > >       val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET); > > -     val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK; > > +     /* status is valid only when START_BUSY is cleared after it > was set */ > > +     if (val & BIT(S_CMD_START_BUSY_SHIFT)) > > +             return; > >  > > +     val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK; > >       if (val == S_CMD_STATUS_TIMEOUT) { > >               dev_err(iproc_i2c->device, "slave random stretch > time timeout\n"); > >  > > @@ -327,70 +320,66 @@ static void bcm_iproc_i2c_check_slave_status( > >  } > >  > >  static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev > *iproc_i2c, > > -                             u32 status) > > +                                 u32 status) > >  { > > -     u8 value; > >       u32 val; > > -     u32 rd_status; > > -     u32 tmp; > > +     u8 value, rx_status; > >  > > -     /* Start of transaction. check address and populate the > direction */ > > -     if (iproc_i2c->xfer_dir == I2C_SLAVE_DIR_NONE) { > > -             tmp = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET); > > -             rd_status = (tmp >> S_RX_STATUS_SHIFT) & > S_RX_STATUS_MASK; > > -             /* This condition checks whether the request is a > new request */ > > -             if (((rd_status == I2C_SLAVE_RX_START) && > > -                     (status & BIT(IS_S_RX_EVENT_SHIFT))) || > > -                     ((rd_status == I2C_SLAVE_RX_END) && > > -                     (status & BIT(IS_S_RD_EVENT_SHIFT)))) { > > - > > -                     /* Last bit is W/R bit. > > -                      * If 1 then its a read request(by master). > > -                      */ > > -                     iproc_i2c->xfer_dir = tmp & > SLAVE_READ_WRITE_BIT_MASK; > > -                     if (iproc_i2c->xfer_dir == I2C_SLAVE_DIR_WRITE) > > -                             i2c_slave_event(iproc_i2c->slave, > > -                                     I2C_SLAVE_READ_REQUESTED, > &value); > > -                     else > > -                             i2c_slave_event(iproc_i2c->slave, > > +     /* Slave RX byte receive */ > > +     if (status & BIT(IS_S_RX_EVENT_SHIFT)) { > > +             val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET); > > +             rx_status = (val >> S_RX_STATUS_SHIFT) & > S_RX_STATUS_MASK; > > +             if (rx_status == I2C_SLAVE_RX_START) { > > +                     /* Start of SMBUS for Master write */ > > +                     i2c_slave_event(iproc_i2c->slave, > >                                       I2C_SLAVE_WRITE_REQUESTED, > &value); > > -             } > > -     } > >  > > -     /* read request from master */ > > -     if ((status & BIT(IS_S_RD_EVENT_SHIFT)) && > > -             (iproc_i2c->xfer_dir == I2C_SLAVE_DIR_WRITE)) { > > -             i2c_slave_event(iproc_i2c->slave, > > -                     I2C_SLAVE_READ_PROCESSED, &value); > > -             iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); > > +                     val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET); > > +                     value = (u8)((val >> S_RX_DATA_SHIFT) & > S_RX_DATA_MASK); > > +                     i2c_slave_event(iproc_i2c->slave, > > +                                     I2C_SLAVE_WRITE_RECEIVED, > &value); > > +             } else if (status & BIT(IS_S_RD_EVENT_SHIFT)) { > > +                     /* Start of SMBUS for Master Read */ > > +                     i2c_slave_event(iproc_i2c->slave, > > +                                     I2C_SLAVE_READ_REQUESTED, > &value); > > +                     iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); > >  > > -             val = BIT(S_CMD_START_BUSY_SHIFT); > > -             iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); > > -     } > > +                     val = BIT(S_CMD_START_BUSY_SHIFT); > > +                     iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); > >  > > -     /* write request from master */ > > -     if ((status & BIT(IS_S_RX_EVENT_SHIFT)) && > > -             (iproc_i2c->xfer_dir == I2C_SLAVE_DIR_READ)) { > > -             val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET); > > -             /* Its a write request by Master to Slave. > > -              * We read data present in receive FIFO > > -              */ > > -             value = (u8)((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK); > > +                     /* > > +                      * Enable interrupt for TX FIFO becomes > empty and > > +                      * less than PKT_LENGTH bytes were output on > the SMBUS > > +                      */ > > +                     val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); > > +                     val |= BIT(IE_S_TX_UNDERRUN_SHIFT); > > +                     iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); > > +             } else { > > +                     /* Master write other than start */ > > +                     value = (u8)((val >> S_RX_DATA_SHIFT) & > S_RX_DATA_MASK); > > +                     i2c_slave_event(iproc_i2c->slave, > > +                                     I2C_SLAVE_WRITE_RECEIVED, > &value); > > +             } > > +     } else if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) { > > +             /* Master read other than start */ > >               i2c_slave_event(iproc_i2c->slave, > > -                     I2C_SLAVE_WRITE_RECEIVED, &value); > > - > > -             /* check the status for the last byte of the > transaction */ > > -             rd_status = (val >> S_RX_STATUS_SHIFT) & > S_RX_STATUS_MASK; > > -             if (rd_status == I2C_SLAVE_RX_END) > > -                     iproc_i2c->xfer_dir = I2C_SLAVE_DIR_NONE; > > +                             I2C_SLAVE_READ_PROCESSED, &value); > >  > > -             dev_dbg(iproc_i2c->device, "\nread value = 0x%x\n", > value); > > +             iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); > > +             val = BIT(S_CMD_START_BUSY_SHIFT); > > +             iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); > >       } > >  > >       /* Stop */ > >       if (status & BIT(IS_S_START_BUSY_SHIFT)) { > >               i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, > &value); > > -             iproc_i2c->xfer_dir = I2C_SLAVE_DIR_NONE; > > +             /* > > +              * Enable interrupt for TX FIFO becomes empty and > > +              * less than PKT_LENGTH bytes were output on the SMBUS > > +              */ > > +             val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET); > > +             val &= ~BIT(IE_S_TX_UNDERRUN_SHIFT); > > +             iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val); > >       } > >  > >       /* clear interrupt status */ > > >