2019-05-09 04:24:54

by Rayagonda Kokatanur

[permalink] [raw]
Subject: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

Add multiple byte read-write support for slave mode.

Signed-off-by: Rayagonda Kokatanur <[email protected]>
Signed-off-by: Srinath Mannam <[email protected]>
---
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 */
--
1.9.1


2019-05-09 16:31:10

by Ray Jui

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

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 <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>
> ---
> 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 */
>

2019-05-09 17:12:48

by Ray Jui

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode



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 <[email protected]
> <mailto:[email protected]> 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
> <[email protected]
> <mailto:[email protected]>>
> > Signed-off-by: Srinath Mannam <[email protected]
> <mailto:[email protected]>>
> > ---
> >  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 */
> >
>

2019-05-15 16:29:48

by Rayagonda Kokatanur

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

No change, it's just duplicate, please ignore first patch and review
second patch.

Best regards
Rayagonda



On Thu, May 9, 2019 at 9:58 PM Ray Jui <[email protected]> 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 <[email protected]>
> > Signed-off-by: Srinath Mannam <[email protected]>
> > ---
> > 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 */
> >

2019-05-27 03:31:41

by Rayagonda Kokatanur

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

Hi All,

Please review the patch and let me know your review comments if any.

Best regards,
Rayagonda


On Wed, May 15, 2019 at 9:58 PM Rayagonda Kokatanur
<[email protected]> wrote:
>
> No change, it's just duplicate, please ignore first patch and review
> second patch.
>
> Best regards
> Rayagonda
>
>
>
> On Thu, May 9, 2019 at 9:58 PM Ray Jui <[email protected]> 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 <[email protected]>
> > > Signed-off-by: Srinath Mannam <[email protected]>
> > > ---
> > > 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 */
> > >

2019-05-27 16:28:03

by Ray Jui

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

Hi Rayagonda,

On 5/8/2019 9:21 PM, Rayagonda Kokatanur wrote:
> Add multiple byte read-write support for slave mode.
>
> Signed-off-by: Rayagonda Kokatanur <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>
> ---
> 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 */
>

This was already reviewed internally. I just reviewed it again and it
looks fine to me. Thanks.

Reviewed-by: Ray Jui <[email protected]>

2019-05-27 19:48:27

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH 1/1] i2c: iproc: Add multi byte read-write support for slave mode

On Thu, May 09, 2019 at 09:51:48AM +0530, Rayagonda Kokatanur wrote:
> Add multiple byte read-write support for slave mode.
>
> Signed-off-by: Rayagonda Kokatanur <[email protected]>
> Signed-off-by: Srinath Mannam <[email protected]>

Applied to for-next, thanks!

But please quote only relevant parts of the message.


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