[PATCH] i2c: omap: re-factor omap_i2c_init function

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti D]

re-factor omap_i2c_init() so that we can re-use it for resume.
While at it also remove the bufstate variable as we write it
in omap_i2c_resize_fifo for every transfer.

Signed-off-by: Shubhrajyoti D <shubhrajyoti-l0cyMroinI0@public.gmane.org>
---
Applies on Felipe's series
http://www.spinics.net/lists/linux-omap/msg79995.html

Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
on omap3636 beagle both idle and suspend.

Functional testing on omap4sdp.

 drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
 1 files changed, 28 insertions(+), 40 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 5e5cefb..338cee7 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -209,7 +209,6 @@ struct omap_i2c_dev {
 	u16			pscstate;
 	u16			scllstate;
 	u16			sclhstate;
-	u16			bufstate;
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
@@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 	}
 }
 
+static void __omap_i2c_init(struct omap_i2c_dev *dev)
+{
+
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
+	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
+
+	/* SCL low and high time values */
+	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
+	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
+	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
+		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
+	/* Take the I2C module out of reset: */
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
+
+}
 static int omap_i2c_init(struct omap_i2c_dev *dev)
 {
-	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
+	u16 psc = 0, scll = 0, sclh = 0;
 	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 	unsigned long fclk_rate = 12000000;
 	unsigned long timeout;
@@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 			 * REVISIT: Some wkup sources might not be needed.
 			 */
 			dev->westate = OMAP_I2C_WE_ALL;
-			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
-							dev->westate);
 		}
 	}
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
 	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 		/*
@@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 	}
 
-	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
-	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
-
-	/* SCL low and high time values */
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
-
-	/* Take the I2C module out of reset: */
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-
 	/* Enable interrupts */
 	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
 			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
 				OMAP_I2C_IE_XDR) : 0);
-	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
-	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-		dev->pscstate = psc;
-		dev->scllstate = scll;
-		dev->sclhstate = sclh;
-		dev->bufstate = buf;
-	}
+
+	dev->pscstate = psc;
+	dev->scllstate = scll;
+	dev->sclhstate = sclh;
+
+	__omap_i2c_init(dev);
+
 	return 0;
 }
 
@@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	if (IS_ERR_VALUE(r))
 		goto err_free_mem;
 
-	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
 
 	dev->errata = 0;
 
@@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
 {
 	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
 
-	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
-		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-	}
-
-	/*
-	 * Don't write to this register if the IE state is 0 as it can
-	 * cause deadlock.
-	 */
-	if (_dev->iestate)
-		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
+	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
+		__omap_i2c_init(_dev);
 
 	return 0;
 }
-- 
1.7.5.4

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti D]

re-factor omap_i2c_init() so that we can re-use it for resume.
While at it also remove the bufstate variable as we write it
in omap_i2c_resize_fifo for every transfer.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
Applies on Felipe's series
http://www.spinics.net/lists/linux-omap/msg79995.html

Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
on omap3636 beagle both idle and suspend.

Functional testing on omap4sdp.

 drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
 1 files changed, 28 insertions(+), 40 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 5e5cefb..338cee7 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -209,7 +209,6 @@ struct omap_i2c_dev {
 	u16			pscstate;
 	u16			scllstate;
 	u16			sclhstate;
-	u16			bufstate;
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
@@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 	}
 }
 
+static void __omap_i2c_init(struct omap_i2c_dev *dev)
+{
+
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
+	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
+
+	/* SCL low and high time values */
+	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
+	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
+	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
+		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
+	/* Take the I2C module out of reset: */
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
+
+}
 static int omap_i2c_init(struct omap_i2c_dev *dev)
 {
-	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
+	u16 psc = 0, scll = 0, sclh = 0;
 	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
 	unsigned long fclk_rate = 12000000;
 	unsigned long timeout;
@@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 			 * REVISIT: Some wkup sources might not be needed.
 			 */
 			dev->westate = OMAP_I2C_WE_ALL;
-			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
-							dev->westate);
 		}
 	}
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
 	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
 		/*
@@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
 	}
 
-	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
-	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
-
-	/* SCL low and high time values */
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
-	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
-
-	/* Take the I2C module out of reset: */
-	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-
 	/* Enable interrupts */
 	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
 			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
 				OMAP_I2C_IE_XDR) : 0);
-	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
-	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-		dev->pscstate = psc;
-		dev->scllstate = scll;
-		dev->sclhstate = sclh;
-		dev->bufstate = buf;
-	}
+
+	dev->pscstate = psc;
+	dev->scllstate = scll;
+	dev->sclhstate = sclh;
+
+	__omap_i2c_init(dev);
+
 	return 0;
 }
 
@@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
 	if (IS_ERR_VALUE(r))
 		goto err_free_mem;
 
-	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
+	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
 
 	dev->errata = 0;
 
@@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
 {
 	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
 
-	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
-		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
-		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
-	}
-
-	/*
-	 * Don't write to this register if the IE state is 0 as it can
-	 * cause deadlock.
-	 */
-	if (_dev->iestate)
-		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
+	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
+		__omap_i2c_init(_dev);
 
 	return 0;
 }
-- 
1.7.5.4

Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 5528 bytes --]

Hi,

On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
> re-factor omap_i2c_init() so that we can re-use it for resume.
> While at it also remove the bufstate variable as we write it
> in omap_i2c_resize_fifo for every transfer.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
> Applies on Felipe's series
> http://www.spinics.net/lists/linux-omap/msg79995.html
> 
> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
> on omap3636 beagle both idle and suspend.
> 
> Functional testing on omap4sdp.
> 
>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>  1 files changed, 28 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 5e5cefb..338cee7 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>  	u16			pscstate;
>  	u16			scllstate;
>  	u16			sclhstate;
> -	u16			bufstate;
>  	u16			syscstate;
>  	u16			westate;
>  	u16			errata;
> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>  	}
>  }
>  
> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
> +{
> +
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> +
> +	/* SCL low and high time values */
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
> +	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
> +		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
> +	/* Take the I2C module out of reset: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> +	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> +
> +}
>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>  {
> -	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
> +	u16 psc = 0, scll = 0, sclh = 0;
>  	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>  	unsigned long fclk_rate = 12000000;
>  	unsigned long timeout;
> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  			 * REVISIT: Some wkup sources might not be needed.
>  			 */
>  			dev->westate = OMAP_I2C_WE_ALL;
> -			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
> -							dev->westate);
>  		}
>  	}
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>  
>  	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>  		/*
> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>  	}
>  
> -	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
> -
> -	/* SCL low and high time values */
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
> -
> -	/* Take the I2C module out of reset: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -
>  	/* Enable interrupts */
>  	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>  			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>  			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>  				OMAP_I2C_IE_XDR) : 0);
> -	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> -	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		dev->pscstate = psc;
> -		dev->scllstate = scll;
> -		dev->sclhstate = sclh;
> -		dev->bufstate = buf;
> -	}
> +
> +	dev->pscstate = psc;
> +	dev->scllstate = scll;
> +	dev->sclhstate = sclh;
> +
> +	__omap_i2c_init(dev);
> +
>  	return 0;
>  }
>  
> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	if (IS_ERR_VALUE(r))
>  		goto err_free_mem;
>  
> -	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
> +	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;

trailing change. not part of $SUBJECT

>  	dev->errata = 0;
>  
> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>  {
>  	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>  
> -	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -	}
> -
> -	/*
> -	 * Don't write to this register if the IE state is 0 as it can
> -	 * cause deadlock.
> -	 */
> -	if (_dev->iestate)
> -		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);

this part is not on __omap_i2c_init() so you're potentially causing a
regression here.

> +	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
> +		__omap_i2c_init(_dev);

how has this been tested ? Did you validate suspend to ram and runtime
pm ?

>  	return 0;
>  }
> -- 
> 1.7.5.4
> 
> --
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-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

Hi,

On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
> re-factor omap_i2c_init() so that we can re-use it for resume.
> While at it also remove the bufstate variable as we write it
> in omap_i2c_resize_fifo for every transfer.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
> Applies on Felipe's series
> http://www.spinics.net/lists/linux-omap/msg79995.html
> 
> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
> on omap3636 beagle both idle and suspend.
> 
> Functional testing on omap4sdp.
> 
>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>  1 files changed, 28 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 5e5cefb..338cee7 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>  	u16			pscstate;
>  	u16			scllstate;
>  	u16			sclhstate;
> -	u16			bufstate;
>  	u16			syscstate;
>  	u16			westate;
>  	u16			errata;
> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>  	}
>  }
>  
> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
> +{
> +
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> +
> +	/* SCL low and high time values */
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
> +	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
> +		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
> +	/* Take the I2C module out of reset: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> +	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> +
> +}
>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>  {
> -	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
> +	u16 psc = 0, scll = 0, sclh = 0;
>  	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>  	unsigned long fclk_rate = 12000000;
>  	unsigned long timeout;
> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  			 * REVISIT: Some wkup sources might not be needed.
>  			 */
>  			dev->westate = OMAP_I2C_WE_ALL;
> -			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
> -							dev->westate);
>  		}
>  	}
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>  
>  	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>  		/*
> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>  	}
>  
> -	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
> -
> -	/* SCL low and high time values */
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
> -
> -	/* Take the I2C module out of reset: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -
>  	/* Enable interrupts */
>  	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>  			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>  			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>  				OMAP_I2C_IE_XDR) : 0);
> -	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> -	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		dev->pscstate = psc;
> -		dev->scllstate = scll;
> -		dev->sclhstate = sclh;
> -		dev->bufstate = buf;
> -	}
> +
> +	dev->pscstate = psc;
> +	dev->scllstate = scll;
> +	dev->sclhstate = sclh;
> +
> +	__omap_i2c_init(dev);
> +
>  	return 0;
>  }
>  
> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	if (IS_ERR_VALUE(r))
>  		goto err_free_mem;
>  
> -	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
> +	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;

trailing change. not part of $SUBJECT

>  	dev->errata = 0;
>  
> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>  {
>  	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>  
> -	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -	}
> -
> -	/*
> -	 * Don't write to this register if the IE state is 0 as it can
> -	 * cause deadlock.
> -	 */
> -	if (_dev->iestate)
> -		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);

this part is not on __omap_i2c_init() so you're potentially causing a
regression here.

> +	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
> +		__omap_i2c_init(_dev);

how has this been tested ? Did you validate suspend to ram and runtime
pm ?

>  	return 0;
>  }
> -- 
> 1.7.5.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
balbi
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Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 10:48 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
>> re-factor omap_i2c_init() so that we can re-use it for resume.
>> While at it also remove the bufstate variable as we write it
>> in omap_i2c_resize_fifo for every transfer.
>>
>> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
>> ---
>> Applies on Felipe's series
>> http://www.spinics.net/lists/linux-omap/msg79995.html
>>
>> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
>> on omap3636 beagle both idle and suspend.
>>
>> Functional testing on omap4sdp.
>>
>>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>>  1 files changed, 28 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
>> index 5e5cefb..338cee7 100644
>> --- a/drivers/i2c/busses/i2c-omap.c
>> +++ b/drivers/i2c/busses/i2c-omap.c
>> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>>       u16                     pscstate;
>>       u16                     scllstate;
>>       u16                     sclhstate;
>> -     u16                     bufstate;
>>       u16                     syscstate;
>>       u16                     westate;
>>       u16                     errata;
>> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>>       }
>>  }
>>
>> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
>> +{
>> +
>> +     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>> +     /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
>> +
>> +     /* SCL low and high time values */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
>> +     omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
>> +     if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
>> +             omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
>> +     /* Take the I2C module out of reset: */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> +     omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
>> +
>> +}
>>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>>  {
>> -     u16 psc = 0, scll = 0, sclh = 0, buf = 0;
>> +     u16 psc = 0, scll = 0, sclh = 0;
>>       u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>>       unsigned long fclk_rate = 12000000;
>>       unsigned long timeout;
>> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>>                        * REVISIT: Some wkup sources might not be needed.
>>                        */
>>                       dev->westate = OMAP_I2C_WE_ALL;
>> -                     omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
>> -                                                     dev->westate);
>>               }
>>       }
>> -     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>>
>>       if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>>               /*
>> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>>               sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>>       }
>>
>> -     /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
>> -
>> -     /* SCL low and high time values */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
>> -     omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
>> -
>> -     /* Take the I2C module out of reset: */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> -
>>       /* Enable interrupts */
>>       dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>>                       OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>>                       ((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>>                               OMAP_I2C_IE_XDR) : 0);
>> -     omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
>> -     if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> -             dev->pscstate = psc;
>> -             dev->scllstate = scll;
>> -             dev->sclhstate = sclh;
>> -             dev->bufstate = buf;
>> -     }
>> +
>> +     dev->pscstate = psc;
>> +     dev->scllstate = scll;
>> +     dev->sclhstate = sclh;
>> +
>> +     __omap_i2c_init(dev);
>> +
>>       return 0;
>>  }
>>
>> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>>       if (IS_ERR_VALUE(r))
>>               goto err_free_mem;
>>
>> -     dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
>> +     dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
>
> trailing change. not part of $SUBJECT

my mistake will remove.

>
>>       dev->errata = 0;
>>
>> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>>  {
>>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>>
>> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> -     }
>> -
>> -     /*
>> -      * Don't write to this register if the IE state is 0 as it can
>> -      * cause deadlock.
>> -      */
>> -     if (_dev->iestate)
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>
> this part is not on __omap_i2c_init() so you're potentially causing a
> regression here.

iestate is set at init so cannot be zero. so the check was removed.

>
>> +     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
>> +             __omap_i2c_init(_dev);
>
> how has this been tested ? Did you validate suspend to ram and runtime
> pm ?

yes.

beagleXm hitting off on idle and suspend path.

and omap4sdp  didnt hit off just suspend to ram.

>
>>       return 0;
>>  }
>> --
>> 1.7.5.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
> --
> balbi

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 10:48 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
>> re-factor omap_i2c_init() so that we can re-use it for resume.
>> While at it also remove the bufstate variable as we write it
>> in omap_i2c_resize_fifo for every transfer.
>>
>> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
>> ---
>> Applies on Felipe's series
>> http://www.spinics.net/lists/linux-omap/msg79995.html
>>
>> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
>> on omap3636 beagle both idle and suspend.
>>
>> Functional testing on omap4sdp.
>>
>>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>>  1 files changed, 28 insertions(+), 40 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
>> index 5e5cefb..338cee7 100644
>> --- a/drivers/i2c/busses/i2c-omap.c
>> +++ b/drivers/i2c/busses/i2c-omap.c
>> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>>       u16                     pscstate;
>>       u16                     scllstate;
>>       u16                     sclhstate;
>> -     u16                     bufstate;
>>       u16                     syscstate;
>>       u16                     westate;
>>       u16                     errata;
>> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>>       }
>>  }
>>
>> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
>> +{
>> +
>> +     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>> +     /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
>> +
>> +     /* SCL low and high time values */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
>> +     omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
>> +     if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
>> +             omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
>> +     /* Take the I2C module out of reset: */
>> +     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> +     omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
>> +
>> +}
>>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>>  {
>> -     u16 psc = 0, scll = 0, sclh = 0, buf = 0;
>> +     u16 psc = 0, scll = 0, sclh = 0;
>>       u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>>       unsigned long fclk_rate = 12000000;
>>       unsigned long timeout;
>> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>>                        * REVISIT: Some wkup sources might not be needed.
>>                        */
>>                       dev->westate = OMAP_I2C_WE_ALL;
>> -                     omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
>> -                                                     dev->westate);
>>               }
>>       }
>> -     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>>
>>       if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>>               /*
>> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>>               sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>>       }
>>
>> -     /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
>> -
>> -     /* SCL low and high time values */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
>> -     omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
>> -
>> -     /* Take the I2C module out of reset: */
>> -     omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> -
>>       /* Enable interrupts */
>>       dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>>                       OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>>                       ((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>>                               OMAP_I2C_IE_XDR) : 0);
>> -     omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
>> -     if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> -             dev->pscstate = psc;
>> -             dev->scllstate = scll;
>> -             dev->sclhstate = sclh;
>> -             dev->bufstate = buf;
>> -     }
>> +
>> +     dev->pscstate = psc;
>> +     dev->scllstate = scll;
>> +     dev->sclhstate = sclh;
>> +
>> +     __omap_i2c_init(dev);
>> +
>>       return 0;
>>  }
>>
>> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>>       if (IS_ERR_VALUE(r))
>>               goto err_free_mem;
>>
>> -     dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
>> +     dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
>
> trailing change. not part of $SUBJECT

my mistake will remove.

>
>>       dev->errata = 0;
>>
>> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>>  {
>>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>>
>> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> -     }
>> -
>> -     /*
>> -      * Don't write to this register if the IE state is 0 as it can
>> -      * cause deadlock.
>> -      */
>> -     if (_dev->iestate)
>> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>
> this part is not on __omap_i2c_init() so you're potentially causing a
> regression here.

iestate is set at init so cannot be zero. so the check was removed.

>
>> +     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
>> +             __omap_i2c_init(_dev);
>
> how has this been tested ? Did you validate suspend to ram and runtime
> pm ?

yes.

beagleXm hitting off on idle and suspend path.

and omap4sdp  didnt hit off just suspend to ram.

>
>>       return 0;
>>  }
>> --
>> 1.7.5.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in
>> the body of a message to majordomo at vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
> --
> balbi

Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 1516 bytes --]

Hi,

On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
> >>  {
> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
> >>
> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> >> -     }
> >> -
> >> -     /*
> >> -      * Don't write to this register if the IE state is 0 as it can
> >> -      * cause deadlock.
> >> -      */
> >> -     if (_dev->iestate)
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
> >
> > this part is not on __omap_i2c_init() so you're potentially causing a
> > regression here.
> 
> iestate is set at init so cannot be zero. so the check was removed.

so you never read it back ? Then you need to add a note for that in
changelog, since this is a behavior change ;-)


-- 
balbi

[-- Attachment #2: Digital signature --]
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[PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

Hi,

On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
> >>  {
> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
> >>
> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> >> -     }
> >> -
> >> -     /*
> >> -      * Don't write to this register if the IE state is 0 as it can
> >> -      * cause deadlock.
> >> -      */
> >> -     if (_dev->iestate)
> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
> >
> > this part is not on __omap_i2c_init() so you're potentially causing a
> > regression here.
> 
> iestate is set at init so cannot be zero. so the check was removed.

so you never read it back ? Then you need to add a note for that in
changelog, since this is a behavior change ;-)


-- 
balbi
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Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 11:27 PM, Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
>> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>> >>  {
>> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>> >>
>> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> >> -     }
>> >> -
>> >> -     /*
>> >> -      * Don't write to this register if the IE state is 0 as it can
>> >> -      * cause deadlock.
>> >> -      */
>> >> -     if (_dev->iestate)
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>> >
>> > this part is not on __omap_i2c_init() so you're potentially causing a
>> > regression here.
>>
>> iestate is set at init so cannot be zero. so the check was removed.
>
> so you never read it back ? Then you need to add a note for that in
> changelog, since this is a behavior change ;-)

Indeed will do.
>
>
> --
> balbi

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 11:27 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
>> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>> >>  {
>> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>> >>
>> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> >> -     }
>> >> -
>> >> -     /*
>> >> -      * Don't write to this register if the IE state is 0 as it can
>> >> -      * cause deadlock.
>> >> -      */
>> >> -     if (_dev->iestate)
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>> >
>> > this part is not on __omap_i2c_init() so you're potentially causing a
>> > regression here.
>>
>> iestate is set at init so cannot be zero. so the check was removed.
>
> so you never read it back ? Then you need to add a note for that in
> changelog, since this is a behavior change ;-)

Indeed will do.
>
>
> --
> balbi

Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

[-- Attachment #1: Type: text/plain, Size: 5355 bytes --]

Hi,

On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
> re-factor omap_i2c_init() so that we can re-use it for resume.
> While at it also remove the bufstate variable as we write it
> in omap_i2c_resize_fifo for every transfer.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti-l0cyMroinI0@public.gmane.org>
> ---
> Applies on Felipe's series
> http://www.spinics.net/lists/linux-omap/msg79995.html
> 
> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
> on omap3636 beagle both idle and suspend.
> 
> Functional testing on omap4sdp.
> 
>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>  1 files changed, 28 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 5e5cefb..338cee7 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>  	u16			pscstate;
>  	u16			scllstate;
>  	u16			sclhstate;
> -	u16			bufstate;
>  	u16			syscstate;
>  	u16			westate;
>  	u16			errata;
> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>  	}
>  }
>  
> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
> +{
> +
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> +
> +	/* SCL low and high time values */
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
> +	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
> +		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
> +	/* Take the I2C module out of reset: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> +	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> +
> +}
>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>  {
> -	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
> +	u16 psc = 0, scll = 0, sclh = 0;
>  	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>  	unsigned long fclk_rate = 12000000;
>  	unsigned long timeout;
> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  			 * REVISIT: Some wkup sources might not be needed.
>  			 */
>  			dev->westate = OMAP_I2C_WE_ALL;
> -			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
> -							dev->westate);
>  		}
>  	}
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>  
>  	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>  		/*
> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>  	}
>  
> -	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
> -
> -	/* SCL low and high time values */
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
> -
> -	/* Take the I2C module out of reset: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -
>  	/* Enable interrupts */
>  	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>  			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>  			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>  				OMAP_I2C_IE_XDR) : 0);
> -	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> -	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		dev->pscstate = psc;
> -		dev->scllstate = scll;
> -		dev->sclhstate = sclh;
> -		dev->bufstate = buf;
> -	}
> +
> +	dev->pscstate = psc;
> +	dev->scllstate = scll;
> +	dev->sclhstate = sclh;
> +
> +	__omap_i2c_init(dev);
> +
>  	return 0;
>  }
>  
> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	if (IS_ERR_VALUE(r))
>  		goto err_free_mem;
>  
> -	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
> +	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
>  
>  	dev->errata = 0;
>  
> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>  {
>  	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>  
> -	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -	}
> -
> -	/*
> -	 * Don't write to this register if the IE state is 0 as it can
> -	 * cause deadlock.
> -	 */
> -	if (_dev->iestate)
> -		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
> +	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
> +		__omap_i2c_init(_dev);
>  
>  	return 0;
>  }

another thing, the few places in omap_i2c_xfer_msg() which are currently
calling omap_i2c_init() should also be converted to call the newly added
__omap_i2c_init(). We don't need to recalculate any of those clock
dividers and whatnot.

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Felipe Balbi]

Hi,

On Tue, Oct 23, 2012 at 08:57:19PM +0530, Shubhrajyoti D wrote:
> re-factor omap_i2c_init() so that we can re-use it for resume.
> While at it also remove the bufstate variable as we write it
> in omap_i2c_resize_fifo for every transfer.
> 
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
> Applies on Felipe's series
> http://www.spinics.net/lists/linux-omap/msg79995.html
> 
> Tested with Terro sys fix + Felipe's stop sched_clock() during suspend
> on omap3636 beagle both idle and suspend.
> 
> Functional testing on omap4sdp.
> 
>  drivers/i2c/busses/i2c-omap.c |   68 +++++++++++++++++------------------------
>  1 files changed, 28 insertions(+), 40 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 5e5cefb..338cee7 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -209,7 +209,6 @@ struct omap_i2c_dev {
>  	u16			pscstate;
>  	u16			scllstate;
>  	u16			sclhstate;
> -	u16			bufstate;
>  	u16			syscstate;
>  	u16			westate;
>  	u16			errata;
> @@ -285,9 +284,26 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
>  	}
>  }
>  
> +static void __omap_i2c_init(struct omap_i2c_dev *dev)
> +{
> +
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
> +
> +	/* SCL low and high time values */
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
> +	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
> +	if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
> +		omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
> +	/* Take the I2C module out of reset: */
> +	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> +	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> +
> +}
>  static int omap_i2c_init(struct omap_i2c_dev *dev)
>  {
> -	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
> +	u16 psc = 0, scll = 0, sclh = 0;
>  	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
>  	unsigned long fclk_rate = 12000000;
>  	unsigned long timeout;
> @@ -337,11 +353,8 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  			 * REVISIT: Some wkup sources might not be needed.
>  			 */
>  			dev->westate = OMAP_I2C_WE_ALL;
> -			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
> -							dev->westate);
>  		}
>  	}
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>  
>  	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
>  		/*
> @@ -426,28 +439,18 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
>  		sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
>  	}
>  
> -	/* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
> -
> -	/* SCL low and high time values */
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
> -	omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
> -
> -	/* Take the I2C module out of reset: */
> -	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -
>  	/* Enable interrupts */
>  	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
>  			OMAP_I2C_IE_NACK | OMAP_I2C_IE_AL)  |
>  			((dev->fifo_size) ? (OMAP_I2C_IE_RDR |
>  				OMAP_I2C_IE_XDR) : 0);
> -	omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
> -	if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		dev->pscstate = psc;
> -		dev->scllstate = scll;
> -		dev->sclhstate = sclh;
> -		dev->bufstate = buf;
> -	}
> +
> +	dev->pscstate = psc;
> +	dev->scllstate = scll;
> +	dev->sclhstate = sclh;
> +
> +	__omap_i2c_init(dev);
> +
>  	return 0;
>  }
>  
> @@ -1136,7 +1139,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	if (IS_ERR_VALUE(r))
>  		goto err_free_mem;
>  
> -	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
> +	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG)  & 0xff;
>  
>  	dev->errata = 0;
>  
> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>  {
>  	struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>  
> -	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
> -		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
> -	}
> -
> -	/*
> -	 * Don't write to this register if the IE state is 0 as it can
> -	 * cause deadlock.
> -	 */
> -	if (_dev->iestate)
> -		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
> +	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
> +		__omap_i2c_init(_dev);
>  
>  	return 0;
>  }

another thing, the few places in omap_i2c_xfer_msg() which are currently
calling omap_i2c_init() should also be converted to call the newly added
__omap_i2c_init(). We don't need to recalculate any of those clock
dividers and whatnot.

-- 
balbi
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Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti]

On 10/24/2012 12:41 AM, Felipe Balbi wrote:
>>
>> >    	return 0;
>> >    }
> another thing, the few places in omap_i2c_xfer_msg() which are currently
> calling omap_i2c_init() should also be converted to call the newly added
> __omap_i2c_init(). We don't need to recalculate any of those clock
> dividers and whatnot.

Yes in fact omap_i2c_init() can be reset - calculate - and __omap_i2c_init.
Then in those places the recalculate can be optimised.

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti]

On 10/24/2012 12:41 AM, Felipe Balbi wrote:
>>
>> >    	return 0;
>> >    }
> another thing, the few places in omap_i2c_xfer_msg() which are currently
> calling omap_i2c_init() should also be converted to call the newly added
> __omap_i2c_init(). We don't need to recalculate any of those clock
> dividers and whatnot.

Yes in fact omap_i2c_init() can be reset - calculate - and __omap_i2c_init.
Then in those places the recalculate can be optimised.

Re: [PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 11:27 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
>> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>> >>  {
>> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>> >>
>> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> >> -     }
>> >> -
>> >> -     /*
>> >> -      * Don't write to this register if the IE state is 0 as it can
>> >> -      * cause deadlock.
>> >> -      */
>> >> -     if (_dev->iestate)
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>> >
>> > this part is not on __omap_i2c_init() so you're potentially causing a
>> > regression here.
>>
>> iestate is set at init so cannot be zero. so the check was removed.
>
Hmm thinking a little more, there is a case that I missed the resume
handler may get called before
the omap_i2c_init will  restore the check and send another version.

[PATCH] i2c: omap: re-factor omap_i2c_init function

[Shubhrajyoti Datta]

On Tue, Oct 23, 2012 at 11:27 PM, Felipe Balbi <balbi@ti.com> wrote:
> Hi,
>
> On Tue, Oct 23, 2012 at 11:26:15PM +0530, Shubhrajyoti Datta wrote:
>> >> @@ -1268,23 +1271,8 @@ static int omap_i2c_runtime_resume(struct device *dev)
>> >>  {
>> >>       struct omap_i2c_dev *_dev = dev_get_drvdata(dev);
>> >>
>> >> -     if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
>> >> -     }
>> >> -
>> >> -     /*
>> >> -      * Don't write to this register if the IE state is 0 as it can
>> >> -      * cause deadlock.
>> >> -      */
>> >> -     if (_dev->iestate)
>> >> -             omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
>> >
>> > this part is not on __omap_i2c_init() so you're potentially causing a
>> > regression here.
>>
>> iestate is set at init so cannot be zero. so the check was removed.
>
Hmm thinking a little more, there is a case that I missed the resume
handler may get called before
the omap_i2c_init will  restore the check and send another version.