[PATCH v2 00/17] Big OMAP I2C Cleanup

[PATCH v2 00/17] Big OMAP I2C Cleanup

[Felipe Balbi]

Hi guys,

I have dropped a few patches from the series and also
tested every single patch on my pandaboard. I2C messages
are still working fine with panda after each patch.

There's still lots of work to be done on the i2c-omap.c
driver but it's now easier to read, IMO.

Changes since v1:
	- removed tabification on patch 6/17
	- removed dev_err() which was introduced on patch 09/17

Felipe Balbi (17):
  i2c: omap: simplify num_bytes handling
  i2c: omap: decrease indentation level on data handling
  i2c: omap: add blank lines
  i2c: omap: simplify omap_i2c_ack_stat()
  i2c: omap: split out [XR]DR and [XR]RDY
  i2c: omap: improve 1p153 errata handling
  i2c: omap: re-factor receive/transmit data loop
  i2c: omap: switch over to do {} while loop
  i2c: omap: ack IRQ in parts
  i2c: omap: get rid of the "complete" label
  i2c: omap: switch to devm_* API
  i2c: omap: switch to platform_get_irq()
  i2c: omap: bus: add a receiver flag
  i2c: omap: simplify errata check
  i2c: omap: always return IRQ_HANDLED
  i2c: omap: simplify IRQ exit path
  i2c: omap: resize fifos before each message

 drivers/i2c/busses/i2c-omap.c |  385 +++++++++++++++++++++++------------------
 1 file changed, 220 insertions(+), 165 deletions(-)

-- 
1.7.10.4

[PATCH v2 01/17] i2c: omap: simplify num_bytes handling

[Felipe Balbi]

trivial patch, no functional changes

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 801df60..9b532cd 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -855,8 +855,7 @@ complete:
 							OMAP_I2C_BUFSTAT_REG)
 							>> 8) & 0x3F;
 			}
-			while (num_bytes) {
-				num_bytes--;
+			while (num_bytes--) {
 				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 				if (dev->buf_len) {
 					*dev->buf++ = w;
@@ -898,8 +897,7 @@ complete:
 							OMAP_I2C_BUFSTAT_REG)
 							& 0x3F;
 			}
-			while (num_bytes) {
-				num_bytes--;
+			while (num_bytes--) {
 				w = 0;
 				if (dev->buf_len) {
 					w = *dev->buf++;
-- 
1.7.10.4

[PATCH v2 02/17] i2c: omap: decrease indentation level on data handling

[Felipe Balbi]

trivial patch, no functional changes.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   63 ++++++++++++++++++++---------------------
 1 file changed, 31 insertions(+), 32 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 9b532cd..39d5583 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -856,22 +856,7 @@ complete:
 							>> 8) & 0x3F;
 			}
 			while (num_bytes--) {
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				if (dev->buf_len) {
-					*dev->buf++ = w;
-					dev->buf_len--;
-					/*
-					 * Data reg in 2430, omap3 and
-					 * omap4 is 8 bit wide
-					 */
-					if (dev->flags &
-						 OMAP_I2C_FLAG_16BIT_DATA_REG) {
-						if (dev->buf_len) {
-							*dev->buf++ = w >> 8;
-							dev->buf_len--;
-						}
-					}
-				} else {
+				if (!dev->buf_len) {
 					if (stat & OMAP_I2C_STAT_RRDY)
 						dev_err(dev->dev,
 							"RRDY IRQ while no data"
@@ -882,6 +867,21 @@ complete:
 								" requested\n");
 					break;
 				}
+
+				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+				*dev->buf++ = w;
+				dev->buf_len--;
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						*dev->buf++ = w >> 8;
+						dev->buf_len--;
+					}
+				}
 			}
 			omap_i2c_ack_stat(dev,
 				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
@@ -898,22 +898,7 @@ complete:
 							& 0x3F;
 			}
 			while (num_bytes--) {
-				w = 0;
-				if (dev->buf_len) {
-					w = *dev->buf++;
-					dev->buf_len--;
-					/*
-					 * Data reg in 2430, omap3 and
-					 * omap4 is 8 bit wide
-					 */
-					if (dev->flags &
-						 OMAP_I2C_FLAG_16BIT_DATA_REG) {
-						if (dev->buf_len) {
-							w |= *dev->buf++ << 8;
-							dev->buf_len--;
-						}
-					}
-				} else {
+				if (!dev->buf_len) {
 					if (stat & OMAP_I2C_STAT_XRDY)
 						dev_err(dev->dev,
 							"XRDY IRQ while no "
@@ -925,6 +910,20 @@ complete:
 					break;
 				}
 
+				w = *dev->buf++;
+				dev->buf_len--;
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						w |= *dev->buf++ << 8;
+						dev->buf_len--;
+					}
+				}
+
 				if ((dev->errata & I2C_OMAP3_1P153) &&
 				    errata_omap3_1p153(dev, &stat, &err))
 					goto complete;
-- 
1.7.10.4

[PATCH v2 03/17] i2c: omap: add blank lines

[Felipe Balbi]

trivial patch to aid readability. No functional
changes.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 39d5583..07ae391 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -829,6 +829,7 @@ complete:
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
 		}
+
 		/*
 		 * ProDB0017052: Clear ARDY bit twice
 		 */
@@ -841,6 +842,7 @@ complete:
 			omap_i2c_complete_cmd(dev, err);
 			return IRQ_HANDLED;
 		}
+
 		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
 			u8 num_bytes = 1;
 
@@ -887,6 +889,7 @@ complete:
 				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
 			continue;
 		}
+
 		if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
 			u8 num_bytes = 1;
 			if (dev->fifo_size) {
@@ -934,10 +937,12 @@ complete:
 				stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
 			continue;
 		}
+
 		if (stat & OMAP_I2C_STAT_ROVR) {
 			dev_err(dev->dev, "Receive overrun\n");
 			dev->cmd_err |= OMAP_I2C_STAT_ROVR;
 		}
+
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
 			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
-- 
1.7.10.4

[PATCH v2 04/17] i2c: omap: simplify omap_i2c_ack_stat()

[Felipe Balbi]

stat & BIT(1) is the same as BIT(1), so let's
simplify things a bit by removing "stat &" from
all omap_i2c_ack_stat() calls.

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 07ae391..fa9ddb6 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -774,8 +774,8 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 
 	while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
 		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
-							OMAP_I2C_STAT_XDR));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
+					OMAP_I2C_STAT_XDR));
 			*err |= OMAP_I2C_STAT_XUDF;
 			return -ETIMEDOUT;
 		}
@@ -835,10 +835,11 @@ complete:
 		 */
 		if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
 					OMAP_I2C_STAT_AL)) {
-			omap_i2c_ack_stat(dev, stat &
-				(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
-				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
-				OMAP_I2C_STAT_ARDY));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
+						OMAP_I2C_STAT_RDR |
+						OMAP_I2C_STAT_XRDY |
+						OMAP_I2C_STAT_XDR |
+						OMAP_I2C_STAT_ARDY));
 			omap_i2c_complete_cmd(dev, err);
 			return IRQ_HANDLED;
 		}
@@ -885,8 +886,8 @@ complete:
 					}
 				}
 			}
-			omap_i2c_ack_stat(dev,
-				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
+						OMAP_I2C_STAT_RDR));
 			continue;
 		}
 
@@ -933,8 +934,8 @@ complete:
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
-			omap_i2c_ack_stat(dev,
-				stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
+			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
+						OMAP_I2C_STAT_XDR));
 			continue;
 		}
 
-- 
1.7.10.4

[PATCH v2 05/17] i2c: omap: split out [XR]DR and [XR]RDY

[Felipe Balbi]

While they do pretty much the same thing, there
are a few peculiarities. Specially WRT erratas,
it's best to split those out and re-factor the
read/write loop to another function which both
cases call.

This last part will be done on another patch.

While at that, also avoid an unncessary register
read since dev->fifo_len will always contain the
correct amount of data to be transferred.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |  126 ++++++++++++++++++++++++++++++-----------
 1 file changed, 92 insertions(+), 34 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index fa9ddb6..0661ca1 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -844,36 +844,62 @@ complete:
 			return IRQ_HANDLED;
 		}
 
-		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
+		if (stat & OMAP_I2C_STAT_RDR) {
 			u8 num_bytes = 1;
 
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
+			while (num_bytes--) {
+				if (!dev->buf_len) {
+					dev_err(dev->dev,
+							"RDR IRQ while no data"
+							" requested\n");
+					break;
+				}
+
+				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+				*dev->buf++ = w;
+				dev->buf_len--;
+
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						*dev->buf++ = w >> 8;
+						dev->buf_len--;
+					}
+				}
+			}
+
 			if (dev->errata & I2C_OMAP_ERRATA_I207)
 				i2c_omap_errata_i207(dev, stat);
 
-			if (dev->fifo_size) {
-				if (stat & OMAP_I2C_STAT_RRDY)
-					num_bytes = dev->fifo_size;
-				else    /* read RXSTAT on RDR interrupt */
-					num_bytes = (omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG)
-							>> 8) & 0x3F;
-			}
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+			continue;
+		}
+
+		if (stat & OMAP_I2C_STAT_RRDY) {
+			u8 num_bytes = 1;
+
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
 			while (num_bytes--) {
 				if (!dev->buf_len) {
-					if (stat & OMAP_I2C_STAT_RRDY)
-						dev_err(dev->dev,
+					dev_err(dev->dev,
 							"RRDY IRQ while no data"
-								" requested\n");
-					if (stat & OMAP_I2C_STAT_RDR)
-						dev_err(dev->dev,
-							"RDR IRQ while no data"
-								" requested\n");
+							" requested\n");
 					break;
 				}
 
 				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 				*dev->buf++ = w;
 				dev->buf_len--;
+
 				/*
 				 * Data reg in 2430, omap3 and
 				 * omap4 is 8 bit wide
@@ -886,36 +912,68 @@ complete:
 					}
 				}
 			}
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
-						OMAP_I2C_STAT_RDR));
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
 			continue;
 		}
 
-		if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
+		if (stat & OMAP_I2C_STAT_XDR) {
 			u8 num_bytes = 1;
-			if (dev->fifo_size) {
-				if (stat & OMAP_I2C_STAT_XRDY)
-					num_bytes = dev->fifo_size;
-				else    /* read TXSTAT on XDR interrupt */
-					num_bytes = omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG)
-							& 0x3F;
+
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
+			while (num_bytes--) {
+				if (!dev->buf_len) {
+					dev_err(dev->dev,
+							"XDR IRQ while no "
+							"data to send\n");
+					break;
+				}
+
+				w = *dev->buf++;
+				dev->buf_len--;
+
+				/*
+				 * Data reg in 2430, omap3 and
+				 * omap4 is 8 bit wide
+				 */
+				if (dev->flags &
+						OMAP_I2C_FLAG_16BIT_DATA_REG) {
+					if (dev->buf_len) {
+						w |= *dev->buf++ << 8;
+						dev->buf_len--;
+					}
+				}
+
+				if ((dev->errata & I2C_OMAP3_1P153) &&
+				    errata_omap3_1p153(dev, &stat, &err))
+					goto complete;
+
+				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
+			continue;
+		}
+
+		if (stat & OMAP_I2C_STAT_XRDY) {
+			u8 num_bytes = 1;
+
+			if (dev->fifo_size)
+				num_bytes = dev->fifo_size;
+
 			while (num_bytes--) {
 				if (!dev->buf_len) {
-					if (stat & OMAP_I2C_STAT_XRDY)
-						dev_err(dev->dev,
+					dev_err(dev->dev,
 							"XRDY IRQ while no "
 							"data to send\n");
-					if (stat & OMAP_I2C_STAT_XDR)
-						dev_err(dev->dev,
-							"XDR IRQ while no "
-							"data to send\n");
 					break;
 				}
 
 				w = *dev->buf++;
 				dev->buf_len--;
+
 				/*
 				 * Data reg in 2430, omap3 and
 				 * omap4 is 8 bit wide
@@ -934,8 +992,8 @@ complete:
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
-			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
-						OMAP_I2C_STAT_XDR));
+
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
 			continue;
 		}
 
-- 
1.7.10.4

[PATCH v2 05/17] i2c: omap: split out [XR]DR and [XR]RDY

[Shubhrajyoti]

Hi Felipe,
On Thursday 14 June 2012 09:54 PM, Felipe Balbi wrote:
>  			return IRQ_HANDLED;
>  		}
>  
> -		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
> +		if (stat & OMAP_I2C_STAT_RDR) {
>  			u8 num_bytes = 1;
>  
> +			if (dev->fifo_size)
> +				num_bytes = dev->fifo_size;
In case of a draining interrupt. The byte count may not be the fifo size.
Do you agree?
> +
> +			while (num_bytes--) {
> +				if (!dev->buf_len) {

[PATCH v2 05/17] i2c: omap: split out [XR]DR and [XR]RDY

[Felipe Balbi]

On Tue, Jun 26, 2012 at 04:11:30PM +0530, Shubhrajyoti wrote:
> Hi Felipe,
> On Thursday 14 June 2012 09:54 PM, Felipe Balbi wrote:
> >  			return IRQ_HANDLED;
> >  		}
> >  
> > -		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
> > +		if (stat & OMAP_I2C_STAT_RDR) {
> >  			u8 num_bytes = 1;
> >  
> > +			if (dev->fifo_size)
> > +				num_bytes = dev->fifo_size;
> In case of a draining interrupt. The byte count may not be the fifo size.
> Do you agree?

hmm... indeed, that should be dev->buf_len... can you fix that up or
want me to resend ?

-- 
balbi
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[PATCH v2 05/17] i2c: omap: split out [XR]DR and [XR]RDY

[Shubhrajyoti]

On Monday 02 July 2012 05:03 PM, Felipe Balbi wrote:
>>> +				num_bytes = dev->fifo_size;
>> > In case of a draining interrupt. The byte count may not be the fifo size.
>> > Do you agree?
> hmm... indeed, that should be dev->buf_len... can you fix that up or
> want me to resend ?
Nope I can fix that up.
Thanks,

[PATCH v2 06/17] i2c: omap: improve 1p153 errata handling

[Felipe Balbi]

Make it not depend on ISR's local variables
in order to make it easier to re-factor the
transmit data loop.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   45 ++++++++++++++++++++++++++++++-----------
 1 file changed, 33 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 0661ca1..41cec32 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -768,21 +768,24 @@ omap_i2c_omap1_isr(int this_irq, void *dev_id)
  * data to DATA_REG. Otherwise some data bytes can be lost while transferring
  * them from the memory to the I2C interface.
  */
-static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
+static int errata_omap3_1p153(struct omap_i2c_dev *dev)
 {
 	unsigned long timeout = 10000;
+	u16 stat;
 
-	while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
-		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
+	do {
+		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		if (stat & OMAP_I2C_STAT_XUDF)
+			break;
+
+		if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 			omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
 					OMAP_I2C_STAT_XDR));
-			*err |= OMAP_I2C_STAT_XUDF;
 			return -ETIMEDOUT;
 		}
 
 		cpu_relax();
-		*stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
-	}
+	} while (--timeout);
 
 	if (!timeout) {
 		dev_err(dev->dev, "timeout waiting on XUDF bit\n");
@@ -946,9 +949,18 @@ complete:
 					}
 				}
 
-				if ((dev->errata & I2C_OMAP3_1P153) &&
-				    errata_omap3_1p153(dev, &stat, &err))
-					goto complete;
+				if (dev->errata & I2C_OMAP3_1P153) {
+					int ret;
+
+					ret = errata_omap3_1p153(dev);
+					stat = omap_i2c_read_reg(dev,
+							OMAP_I2C_STAT_REG);
+
+					if (ret < 0) {
+						err |= OMAP_I2C_STAT_XUDF;
+						goto complete;
+					}
+				}
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
@@ -986,9 +998,18 @@ complete:
 					}
 				}
 
-				if ((dev->errata & I2C_OMAP3_1P153) &&
-				    errata_omap3_1p153(dev, &stat, &err))
-					goto complete;
+				if (dev->errata & I2C_OMAP3_1P153) {
+					int ret;
+
+					ret = errata_omap3_1p153(dev);
+					stat = omap_i2c_read_reg(dev,
+							OMAP_I2C_STAT_REG);
+
+					if (ret < 0) {
+						err |= OMAP_I2C_STAT_XUDF;
+						goto complete;
+					}
+				}
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
 			}
-- 
1.7.10.4

[PATCH v2 07/17] i2c: omap: re-factor receive/transmit data loop

[Felipe Balbi]

re-factor the common parts to a separate function,
so that code is easier to read and understand.

No functional changes.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |  208 +++++++++++++++++------------------------
 1 file changed, 84 insertions(+), 124 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 41cec32..94d6c6a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -795,12 +795,81 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev)
 	return 0;
 }
 
+static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
+		bool is_rdr)
+{
+	u16		w;
+
+	while (num_bytes--) {
+		if (!dev->buf_len) {
+			dev_err(dev->dev, "%s without data",
+					is_rdr ? "RDR" : "RRDY");
+			break;
+		}
+
+		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+		*dev->buf++ = w;
+		dev->buf_len--;
+
+		/*
+		 * Data reg in 2430, omap3 and
+		 * omap4 is 8 bit wide
+		 */
+		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			if (dev->buf_len) {
+				*dev->buf++ = w >> 8;
+				dev->buf_len--;
+			}
+		}
+	}
+}
+
+static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
+		bool is_xdr)
+{
+	u16		w;
+
+	while (num_bytes--) {
+		if (!dev->buf_len) {
+			dev_err(dev->dev, "%s without data",
+					is_xdr ? "XDR" : "XRDY");
+			break;
+		}
+
+		w = *dev->buf++;
+		dev->buf_len--;
+
+		/*
+		 * Data reg in 2430, omap3 and
+		 * omap4 is 8 bit wide
+		 */
+		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+			if (dev->buf_len) {
+				w |= *dev->buf++ << 8;
+				dev->buf_len--;
+			}
+		}
+
+		if (dev->errata & I2C_OMAP3_1P153) {
+			int ret;
+
+			ret = errata_omap3_1p153(dev);
+			if (ret < 0)
+				return ret;
+		}
+
+		omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+	}
+
+	return 0;
+}
+
 static irqreturn_t
 omap_i2c_isr(int this_irq, void *dev_id)
 {
 	struct omap_i2c_dev *dev = dev_id;
 	u16 bits;
-	u16 stat, w;
+	u16 stat;
 	int err, count = 0;
 
 	if (pm_runtime_suspended(dev->dev))
@@ -853,30 +922,7 @@ complete:
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"RDR IRQ while no data"
-							" requested\n");
-					break;
-				}
-
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				*dev->buf++ = w;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						*dev->buf++ = w >> 8;
-						dev->buf_len--;
-					}
-				}
-			}
+			omap_i2c_receive_data(dev, num_bytes, true);
 
 			if (dev->errata & I2C_OMAP_ERRATA_I207)
 				i2c_omap_errata_i207(dev, stat);
@@ -891,78 +937,23 @@ complete:
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"RRDY IRQ while no data"
-							" requested\n");
-					break;
-				}
-
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				*dev->buf++ = w;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						*dev->buf++ = w >> 8;
-						dev->buf_len--;
-					}
-				}
-			}
-
+			omap_i2c_receive_data(dev, num_bytes, false);
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
 			continue;
 		}
 
 		if (stat & OMAP_I2C_STAT_XDR) {
+			int ret;
 			u8 num_bytes = 1;
 
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"XDR IRQ while no "
-							"data to send\n");
-					break;
-				}
-
-				w = *dev->buf++;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						w |= *dev->buf++ << 8;
-						dev->buf_len--;
-					}
-				}
-
-				if (dev->errata & I2C_OMAP3_1P153) {
-					int ret;
-
-					ret = errata_omap3_1p153(dev);
-					stat = omap_i2c_read_reg(dev,
-							OMAP_I2C_STAT_REG);
-
-					if (ret < 0) {
-						err |= OMAP_I2C_STAT_XUDF;
-						goto complete;
-					}
-				}
-
-				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+			ret = omap_i2c_transmit_data(dev, num_bytes, true);
+			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+			if (ret < 0) {
+				err |= OMAP_I2C_STAT_XUDF;
+				goto complete;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
@@ -970,48 +961,17 @@ complete:
 		}
 
 		if (stat & OMAP_I2C_STAT_XRDY) {
+			int ret;
 			u8 num_bytes = 1;
 
 			if (dev->fifo_size)
 				num_bytes = dev->fifo_size;
 
-			while (num_bytes--) {
-				if (!dev->buf_len) {
-					dev_err(dev->dev,
-							"XRDY IRQ while no "
-							"data to send\n");
-					break;
-				}
-
-				w = *dev->buf++;
-				dev->buf_len--;
-
-				/*
-				 * Data reg in 2430, omap3 and
-				 * omap4 is 8 bit wide
-				 */
-				if (dev->flags &
-						OMAP_I2C_FLAG_16BIT_DATA_REG) {
-					if (dev->buf_len) {
-						w |= *dev->buf++ << 8;
-						dev->buf_len--;
-					}
-				}
-
-				if (dev->errata & I2C_OMAP3_1P153) {
-					int ret;
-
-					ret = errata_omap3_1p153(dev);
-					stat = omap_i2c_read_reg(dev,
-							OMAP_I2C_STAT_REG);
-
-					if (ret < 0) {
-						err |= OMAP_I2C_STAT_XUDF;
-						goto complete;
-					}
-				}
-
-				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
+			ret = omap_i2c_transmit_data(dev, num_bytes, false);
+			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+			if (ret < 0) {
+				err |= OMAP_I2C_STAT_XUDF;
+				goto complete;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
-- 
1.7.10.4

[PATCH v2 08/17] i2c: omap: switch over to do {} while loop

[Felipe Balbi]

this will make sure that we execute at least once.
No functional changes otherwise.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 94d6c6a..a035d16 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -870,20 +870,29 @@ omap_i2c_isr(int this_irq, void *dev_id)
 	struct omap_i2c_dev *dev = dev_id;
 	u16 bits;
 	u16 stat;
-	int err, count = 0;
+	int err = 0, count = 0;
 
 	if (pm_runtime_suspended(dev->dev))
 		return IRQ_NONE;
 
-	bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
-	while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
+	do {
+		bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
+		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+		stat &= bits;
+
+		if (!stat) {
+			/* my work here is done */
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
+		}
+
 		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
 			dev_warn(dev->dev, "Too much work in one IRQ\n");
-			break;
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
-		err = 0;
 complete:
 		/*
 		 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
@@ -987,7 +996,7 @@ complete:
 			dev_err(dev->dev, "Transmit underflow\n");
 			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
 		}
-	}
+	} while (stat);
 
 	return count ? IRQ_HANDLED : IRQ_NONE;
 }
-- 
1.7.10.4

[PATCH v2 09/17] i2c: omap: ack IRQ in parts

[Felipe Balbi]

According to flow diagrams on OMAP TRMs,
we should ACK the IRQ as they happen.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index a035d16..83ae06a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -894,21 +894,19 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		}
 
 complete:
-		/*
-		 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
-		 * acked after the data operation is complete.
-		 * Ref: TRM SWPU114Q Figure 18-31
-		 */
-		omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
-				~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
-				OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
-
-		if (stat & OMAP_I2C_STAT_NACK)
+		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
+		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
 		/*
@@ -989,12 +987,18 @@ complete:
 
 		if (stat & OMAP_I2C_STAT_ROVR) {
 			dev_err(dev->dev, "Receive overrun\n");
-			dev->cmd_err |= OMAP_I2C_STAT_ROVR;
+			err |= OMAP_I2C_STAT_ROVR;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
-			dev->cmd_err |= OMAP_I2C_STAT_XUDF;
+			err |= OMAP_I2C_STAT_XUDF;
+			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
+			omap_i2c_complete_cmd(dev, err);
+			return IRQ_HANDLED;
 		}
 	} while (stat);
 
-- 
1.7.10.4

[PATCH v2 10/17] i2c: omap: get rid of the "complete" label

[Felipe Balbi]

we can ack stat and complete the command from
the errata handling itself.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 83ae06a..7171ea1 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -893,7 +893,6 @@ omap_i2c_isr(int this_irq, void *dev_id)
 			return IRQ_HANDLED;
 		}
 
-complete:
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
@@ -957,10 +956,12 @@ complete:
 				num_bytes = dev->fifo_size;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, true);
-			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0) {
 				err |= OMAP_I2C_STAT_XUDF;
-				goto complete;
+				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF |
+						OMAP_I2C_STAT_XDR);
+				omap_i2c_complete_cmd(dev, err);
+				return IRQ_HANDLED;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
@@ -975,10 +976,12 @@ complete:
 				num_bytes = dev->fifo_size;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
-			stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 			if (ret < 0) {
 				err |= OMAP_I2C_STAT_XUDF;
-				goto complete;
+				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF |
+						OMAP_I2C_STAT_XRDY);
+				omap_i2c_complete_cmd(dev, err);
+				return IRQ_HANDLED;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
-- 
1.7.10.4

[PATCH v2 11/17] i2c: omap: switch to devm_* API

[Felipe Balbi]

that helps deleting some boiler plate code
and lets driver-core manage our resources
for us.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   43 +++++++++++------------------------------
 1 file changed, 11 insertions(+), 32 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 7171ea1..e368f67 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1044,7 +1044,7 @@ omap_i2c_probe(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev;
 	struct i2c_adapter	*adap;
-	struct resource		*mem, *irq, *ioarea;
+	struct resource		*mem, *irq;
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;
@@ -1057,23 +1057,17 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "no mem resource?\n");
 		return -ENODEV;
 	}
+
 	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq) {
 		dev_err(&pdev->dev, "no irq resource?\n");
 		return -ENODEV;
 	}
 
-	ioarea = request_mem_region(mem->start, resource_size(mem),
-			pdev->name);
-	if (!ioarea) {
-		dev_err(&pdev->dev, "I2C region already claimed\n");
-		return -EBUSY;
-	}
-
-	dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
+	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
 	if (!dev) {
-		r = -ENOMEM;
-		goto err_release_region;
+		dev_err(&pdev->dev, "not enough memory\n");
+		return -ENOMEM;
 	}
 
 	match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
@@ -1096,10 +1090,10 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	dev->dev = &pdev->dev;
 	dev->irq = irq->start;
-	dev->base = ioremap(mem->start, resource_size(mem));
+	dev->base = devm_request_and_ioremap(&pdev->dev, mem);
 	if (!dev->base) {
-		r = -ENOMEM;
-		goto err_free_mem;
+		dev_err(&pdev->dev, "ioremap failed\n");
+		return -ENOMEM;
 	}
 
 	platform_set_drvdata(pdev, dev);
@@ -1150,7 +1144,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
 								   omap_i2c_isr;
-	r = request_irq(dev->irq, isr, 0, pdev->name, dev);
+	r = devm_request_irq(&pdev->dev, dev->irq, isr, 0, pdev->name, dev);
 
 	if (r) {
 		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
@@ -1176,24 +1170,16 @@ omap_i2c_probe(struct platform_device *pdev)
 	r = i2c_add_numbered_adapter(adap);
 	if (r) {
 		dev_err(dev->dev, "failure adding adapter\n");
-		goto err_free_irq;
+		goto err_unuse_clocks;
 	}
 
 	of_i2c_register_devices(adap);
 
 	return 0;
 
-err_free_irq:
-	free_irq(dev->irq, dev);
 err_unuse_clocks:
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(dev->dev);
-	iounmap(dev->base);
-err_free_mem:
-	platform_set_drvdata(pdev, NULL);
-	kfree(dev);
-err_release_region:
-	release_mem_region(mem->start, resource_size(mem));
 
 	return r;
 }
@@ -1202,17 +1188,10 @@ static int
 omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
-	struct resource		*mem;
 
-	platform_set_drvdata(pdev, NULL);
-
-	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
-	iounmap(dev->base);
-	kfree(dev);
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	release_mem_region(mem->start, resource_size(mem));
+
 	return 0;
 }
 
-- 
1.7.10.4

[PATCH v2 12/17] i2c: omap: switch to platform_get_irq()

[Felipe Balbi]

that's a nice helper from drivers core which
will give us the exact IRQ number, instead
of a pointer to an IRQ resource.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index e368f67..be7ac1a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1044,11 +1044,12 @@ omap_i2c_probe(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev;
 	struct i2c_adapter	*adap;
-	struct resource		*mem, *irq;
+	struct resource		*mem;
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;
 	irq_handler_t isr;
+	int irq;
 	int r;
 
 	/* NOTE: driver uses the static register mapping */
@@ -1058,10 +1059,10 @@ omap_i2c_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-	if (!irq) {
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
 		dev_err(&pdev->dev, "no irq resource?\n");
-		return -ENODEV;
+		return irq;
 	}
 
 	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
@@ -1089,7 +1090,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	}
 
 	dev->dev = &pdev->dev;
-	dev->irq = irq->start;
+	dev->irq = irq;
 	dev->base = devm_request_and_ioremap(&pdev->dev, mem);
 	if (!dev->base) {
 		dev_err(&pdev->dev, "ioremap failed\n");
-- 
1.7.10.4

[PATCH v2 13/17] i2c: omap: bus: add a receiver flag

[Felipe Balbi]

that way we can ignore TX IRQs while in receiver
mode and ignore RX IRQs while in transmitter mode.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index be7ac1a..6a7395a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -199,6 +199,7 @@ struct omap_i2c_dev {
 						 */
 	u8			rev;
 	unsigned		b_hw:1;		/* bad h/w fixes */
+	unsigned		receiver:1;	/* true when we're in receiver mode */
 	u16			iestate;	/* Saved interrupt register */
 	u16			pscstate;
 	u16			scllstate;
@@ -538,6 +539,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 
 	init_completion(&dev->cmd_complete);
 	dev->cmd_err = 0;
+	dev->receiver = !!(msg->flags & I2C_M_RD);
 
 	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 
@@ -880,6 +882,13 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
 		stat &= bits;
 
+		/* If we're in receiver mode, ignore XDR/XRDY */
+		if (dev->receiver) {
+			stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
+		} else {
+			stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
+		}
+
 		if (!stat) {
 			/* my work here is done */
 			omap_i2c_complete_cmd(dev, err);
-- 
1.7.10.4

[PATCH v2 14/17] i2c: omap: simplify errata check

[Felipe Balbi]

omap_i2c_dev is allocated with kzalloc(),
so we need not initialize b_hw to zero.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 6a7395a..6e97d86 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1138,9 +1138,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
 		dev->fifo_size = (dev->fifo_size / 2);
 
-		if (dev->rev >= OMAP_I2C_REV_ON_3530_4430)
-			dev->b_hw = 0; /* Disable hardware fixes */
-		else
+		if (dev->rev < OMAP_I2C_REV_ON_3530_4430)
 			dev->b_hw = 1; /* Enable hardware fixes */
 
 		/* calculate wakeup latency constraint for MPU */
-- 
1.7.10.4

[PATCH v2 15/17] i2c: omap: always return IRQ_HANDLED

[Felipe Balbi]

otherwise we could get our IRQ line disabled due
to many spurious IRQs.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 6e97d86..572fad7 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1014,7 +1014,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		}
 	} while (stat);
 
-	return count ? IRQ_HANDLED : IRQ_NONE;
+	return IRQ_HANDLED;
 }
 
 static const struct i2c_algorithm omap_i2c_algo = {
-- 
1.7.10.4

[PATCH v2 16/17] i2c: omap: simplify IRQ exit path

[Felipe Balbi]

instead of having multiple return points, use
a goto statement to make that clearer.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 572fad7..82cb7d4 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -889,32 +889,26 @@ omap_i2c_isr(int this_irq, void *dev_id)
 			stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
 		}
 
-		if (!stat) {
-			/* my work here is done */
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
-		}
+		if (!stat)
+			goto out;
 
 		dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
 		if (count++ == 100) {
 			dev_warn(dev->dev, "Too much work in one IRQ\n");
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_NACK) {
 			err |= OMAP_I2C_STAT_NACK;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_AL) {
 			dev_err(dev->dev, "Arbitration lost\n");
 			err |= OMAP_I2C_STAT_AL;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		/*
@@ -927,8 +921,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 						OMAP_I2C_STAT_XRDY |
 						OMAP_I2C_STAT_XDR |
 						OMAP_I2C_STAT_ARDY));
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_RDR) {
@@ -969,8 +962,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				err |= OMAP_I2C_STAT_XUDF;
 				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF |
 						OMAP_I2C_STAT_XDR);
-				omap_i2c_complete_cmd(dev, err);
-				return IRQ_HANDLED;
+				goto out;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
@@ -989,8 +981,7 @@ omap_i2c_isr(int this_irq, void *dev_id)
 				err |= OMAP_I2C_STAT_XUDF;
 				omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF |
 						OMAP_I2C_STAT_XRDY);
-				omap_i2c_complete_cmd(dev, err);
-				return IRQ_HANDLED;
+				goto out;
 			}
 
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
@@ -1001,19 +992,19 @@ omap_i2c_isr(int this_irq, void *dev_id)
 			dev_err(dev->dev, "Receive overrun\n");
 			err |= OMAP_I2C_STAT_ROVR;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 
 		if (stat & OMAP_I2C_STAT_XUDF) {
 			dev_err(dev->dev, "Transmit underflow\n");
 			err |= OMAP_I2C_STAT_XUDF;
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
-			omap_i2c_complete_cmd(dev, err);
-			return IRQ_HANDLED;
+			goto out;
 		}
 	} while (stat);
 
+out:
+	omap_i2c_complete_cmd(dev, err);
 	return IRQ_HANDLED;
 }
 
-- 
1.7.10.4

[PATCH v2 17/17] i2c: omap: resize fifos before each message

[Felipe Balbi]

This patch will try to avoid the usage of
draining feature by reconfiguring the FIFO
the start condition of each message based
on the message's size.

By doing that, we will be better utilizing
the FIFO when doing big transfers.

While at that also drop the now uneeded
check for dev->buf_len as we always know
the amount of data to be transmitted.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   83 +++++++++++++++++++++++++----------------
 1 file changed, 51 insertions(+), 32 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 82cb7d4..aa14e24 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -193,6 +193,7 @@ struct omap_i2c_dev {
 	u8			*regs;
 	size_t			buf_len;
 	struct i2c_adapter	adapter;
+	u8			threshold;
 	u8			fifo_size;	/* use as flag and value
 						 * fifo_size==0 implies no fifo
 						 * if set, should be trsh+1
@@ -459,13 +460,6 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
 	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
 
-	if (dev->fifo_size) {
-		/* Note: setup required fifo size - 1. RTRSH and XTRSH */
-		buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
-			(dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
-		omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
-	}
-
 	/* Take the I2C module out of reset: */
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 
@@ -508,6 +502,45 @@ static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 	return 0;
 }
 
+static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
+{
+	u16		buf;
+
+	if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
+		return;
+
+	/*
+	 * Set up notification threshold based on message size. We're doing
+	 * this to try and avoid draining feature as much as possible. Whenever
+	 * we have big messages to transfer (bigger than our total fifo size)
+	 * then we might use draining feature to transfer the remaining bytes.
+	 */
+
+	dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
+
+	buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
+
+	if (is_rx) {
+		/* Clear RX Threshold */
+		buf &= ~(0x3f << 8);
+		buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
+	} else {
+		/* Clear TX Threshold */
+		buf &= ~0x3f;
+		buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
+	}
+
+	omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
+
+	if (dev->rev < OMAP_I2C_REV_ON_3530_4430)
+		dev->b_hw = 1; /* Enable hardware fixes */
+
+	/* calculate wakeup latency constraint for MPU */
+	if (dev->set_mpu_wkup_lat != NULL)
+		dev->latency = (1000000 * dev->threshold) /
+			(1000 * dev->speed / 8);
+}
+
 /*
  * Low level master read/write transaction.
  */
@@ -524,6 +557,9 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	if (msg->len == 0)
 		return -EINVAL;
 
+	dev->receiver = !!(msg->flags & I2C_M_RD);
+	omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
+
 	omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
 
 	/* REVISIT: Could the STB bit of I2C_CON be used with probing? */
@@ -539,7 +575,6 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 
 	init_completion(&dev->cmd_complete);
 	dev->cmd_err = 0;
-	dev->receiver = !!(msg->flags & I2C_M_RD);
 
 	w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
 
@@ -803,12 +838,6 @@ static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 	u16		w;
 
 	while (num_bytes--) {
-		if (!dev->buf_len) {
-			dev_err(dev->dev, "%s without data",
-					is_rdr ? "RDR" : "RRDY");
-			break;
-		}
-
 		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
 		*dev->buf++ = w;
 		dev->buf_len--;
@@ -818,10 +847,8 @@ static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
 		 * omap4 is 8 bit wide
 		 */
 		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			if (dev->buf_len) {
-				*dev->buf++ = w >> 8;
-				dev->buf_len--;
-			}
+			*dev->buf++ = w >> 8;
+			dev->buf_len--;
 		}
 	}
 }
@@ -832,12 +859,6 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 	u16		w;
 
 	while (num_bytes--) {
-		if (!dev->buf_len) {
-			dev_err(dev->dev, "%s without data",
-					is_xdr ? "XDR" : "XRDY");
-			break;
-		}
-
 		w = *dev->buf++;
 		dev->buf_len--;
 
@@ -846,10 +867,8 @@ static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
 		 * omap4 is 8 bit wide
 		 */
 		if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
-			if (dev->buf_len) {
-				w |= *dev->buf++ << 8;
-				dev->buf_len--;
-			}
+			w |= *dev->buf++ << 8;
+			dev->buf_len--;
 		}
 
 		if (dev->errata & I2C_OMAP3_1P153) {
@@ -942,8 +961,8 @@ omap_i2c_isr(int this_irq, void *dev_id)
 		if (stat & OMAP_I2C_STAT_RRDY) {
 			u8 num_bytes = 1;
 
-			if (dev->fifo_size)
-				num_bytes = dev->fifo_size;
+			if (dev->threshold)
+				num_bytes = dev->threshold;
 
 			omap_i2c_receive_data(dev, num_bytes, false);
 			omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
@@ -973,8 +992,8 @@ omap_i2c_isr(int this_irq, void *dev_id)
 			int ret;
 			u8 num_bytes = 1;
 
-			if (dev->fifo_size)
-				num_bytes = dev->fifo_size;
+			if (dev->threshold)
+				num_bytes = dev->threshold;
 
 			ret = omap_i2c_transmit_data(dev, num_bytes, false);
 			if (ret < 0) {
-- 
1.7.10.4

[PATCH v2 00/17] Big OMAP I2C Cleanup

[Wolfram Sang]

On Thu, Jun 14, 2012 at 07:24:10PM +0300, Felipe Balbi wrote:
> Hi guys,
> 
> I have dropped a few patches from the series and also
> tested every single patch on my pandaboard. I2C messages
> are still working fine with panda after each patch.
> 
> There's still lots of work to be done on the i2c-omap.c
> driver but it's now easier to read, IMO.
> 
> Changes since v1:
> 	- removed tabification on patch 6/17
> 	- removed dev_err() which was introduced on patch 09/17

To prevent the list being flooded, I would appreciate if you could wait
a few days to collect reviews before resending. It will take some time
until I pick this series anyhow, because I want people to have time to
donate Tested-by tags.

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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[PATCH v2 00/17] Big OMAP I2C Cleanup

[Shubhrajyoti]

On Thursday 14 June 2012 11:29 PM, Wolfram Sang wrote:
>> 	- removed dev_err() which was introduced on patch 09/17
> To prevent the list being flooded, I would appreciate if you could wait
> a few days to collect reviews before resending. It will take some time
> until I pick this series anyhow, because I want people to have time to
> donate Tested-by tags.
Felipe thats a good cleanup.
The series look good to me.

Also draining interrupt I had some queries.
Looks good to me.

I have tested it after rebasing.
Tested-by : Shubhrajyoti <shubhrajyoti@ti.com>


Thanks,

[PATCH v2 00/17] Big OMAP I2C Cleanup

[Felipe Balbi]

Hi,

On Tue, Jun 26, 2012 at 04:21:30PM +0530, Shubhrajyoti wrote:
> On Thursday 14 June 2012 11:29 PM, Wolfram Sang wrote:
> >> 	- removed dev_err() which was introduced on patch 09/17
> > To prevent the list being flooded, I would appreciate if you could wait
> > a few days to collect reviews before resending. It will take some time
> > until I pick this series anyhow, because I want people to have time to
> > donate Tested-by tags.
> Felipe thats a good cleanup.
> The series look good to me.
> 
> Also draining interrupt I had some queries.
> Looks good to me.
> 
> I have tested it after rebasing.

rebasing on top of what ? You should resend the series so that I know
what changes you have made to my original patchset. Make sure to list on
the commit log what where the changes you made, so that it looks
something like this commit below where I changed commit log a bit:

| commit 3daf74d78dfcd552445c35f1b82a271ca305ceb9
| Author: Pratyush Anand <pratyush.anand@st.com>
| Date:   Sat Jun 23 02:23:08 2012 +0530
| 
| usb: dwc3: remove WARN_ON from dwc_stop_active_transfer
| 
| Now we are sure that, if res_trans_idx is zero, then endpoint has been
| stopped. So it's safe to just return if endpoint is already stopped. No
| need to generate warning anymore.
| 
| While doing so, it's better to return when res_trans_idx is zero and
| decrease one level of indentation.
| 
| Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
| 
| [ balbi at ti.com: slightly changed commit log ]
| 
| Signed-off-by: Felipe Balbi <balbi@ti.com>

> Tested-by : Shubhrajyoti <shubhrajyoti@ti.com>

since you will send, you should, probably, add your Signed-off-by,
instead of Tested-by. dunno.

-- 
balbi
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[PATCH v2 00/17] Big OMAP I2C Cleanup

[Shubhrajyoti]

On Monday 02 July 2012 05:07 PM, Felipe Balbi wrote:
> Hi,
>
> On Tue, Jun 26, 2012 at 04:21:30PM +0530, Shubhrajyoti wrote:
>> On Thursday 14 June 2012 11:29 PM, Wolfram Sang wrote:
>>>> 	- removed dev_err() which was introduced on patch 09/17
>>> To prevent the list being flooded, I would appreciate if you could wait
>>> a few days to collect reviews before resending. It will take some time
>>> until I pick this series anyhow, because I want people to have time to
>>> donate Tested-by tags.
>> Felipe thats a good cleanup.
>> The series look good to me.
>>
>> Also draining interrupt I had some queries.
>> Looks good to me.
>>
>> I have tested it after rebasing.
> rebasing on top of what ? 
On top of embedded i2c branch of Wolfram.

> You should resend the series so that I know
> what changes you have made to my original patchset. Make sure to list on
> the commit log what where the changes you made, so that it looks
> something like this commit below where I changed commit log a bit:
Will do that.
Thanks,

> | commit 3daf74d78dfcd552445c35f1b82a271ca305ceb9
> | Author: Pratyush Anand <pratyush.anand@st.com>
> | Date:   Sat Jun 23 02:23:08 2012 +0530
> | 
> | usb: dwc3: remove WARN_ON from dwc_stop_active_transfer
> | 
> | Now we are sure that, if res_trans_idx is zero, then endpoint has been
> | stopped. So it's safe to just return if endpoint is already stopped. No
> | need to generate warning anymore.
> | 
> | While doing so, it's better to return when res_trans_idx is zero and
> | decrease one level of indentation.
> | 
> | Signed-off-by: Pratyush Anand <pratyush.anand@st.com>
> | 
> | [ balbi at ti.com: slightly changed commit log ]
> | 
> | Signed-off-by: Felipe Balbi <balbi@ti.com>
>
>> Tested-by : Shubhrajyoti <shubhrajyoti@ti.com>
> since you will send, you should, probably, add your Signed-off-by,
> instead of Tested-by. dunno.
>