[PATCHv9 00/10] I2C fixes

[PATCHv9 00/10] I2C fixes

[Shubhrajyoti D]

The patch series does the following

- Warn fixes if CONFIG_PM_RUNTIME is not selected.
- In case of i2c remove register access was done without any
 get_sync fix the same.
- Folds a patch from Tasslehoff to prevent any merge conflicts.
- Prevents the XDUF flag to be set if the underflow condition is not met.
- As per discussion in [1] .Adds a patch to rename the 1p153 errata and
 use the unique id instead as the section number in the recent errata
 docs has changed.

v9:
Fix the comments from Wolfram Sang

[1] http://www.spinics.net/lists/linux-i2c/msg07607.html

Tested on omap4sdp and omap3sdp.

The following changes since commit b821861b905a79f71746945237968c3382d99adc:

  Merge tag 'ktest-for-v3.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest (2012-05-01 19:43:34 -0700)

are available in the git repository at:

  git://gitorious.org/linus-tree/linus-tree.git i2c_omap-fixes

Shubhrajyoti D (9):
      I2C: OMAP: make omap_i2c_unidle/idle functions depend on CONFIG_PM_RUNTIME
      I2C: OMAP: Fix the mismatch of pm_runtime enable and disable
      I2C: OMAP: Fix the interrupt clearing in OMAP4
      I2C: OMAP: Prevent the register access after pm_runtime_put in probe
      I2C: OMAP: Don't check if wait_for_completion_timeout() returns less than zero
      I2C: OMAP: Fix the crash in i2c remove
      I2C: OMAP: Handle error check for pm runtime
      I2C: OMAP: Do not set the XUDF(Transmit underflow) if the underflow is not reached
      I2C: OMAP: Rename the 1p153 to the erratum id i462

Tasslehoff Kjappfot (1):
      I2C: OMAP: prevent the overwrite of the errata flags

 drivers/i2c/busses/i2c-omap.c |  127 ++++++++++++++++++++---------------------
 1 files changed, 62 insertions(+), 65 deletions(-)

-- 
1.7.5.4

[PATCHv9 01/10] I2C: OMAP: make omap_i2c_unidle/idle functions depend on CONFIG_PM_RUNTIME

[Shubhrajyoti D]

The functions omap_i2c_unidle/idle are called from omap_i2c_runtime_resume
and omap_i2c_runtime_suspend which is compiled for CONFIG_PM_RUNTIME.
This patch removes the omap_i2c_unidle/idle functions and folds them
into the runtime callbacks.

This fixes the below warn when CONFIG_PM_RUNTIME is not defined

 CC      arch/arm/mach-omap2/board-ti8168evm.o
drivers/i2c/busses/i2c-omap.c:272: warning: 'omap_i2c_unidle' defined but not used
drivers/i2c/busses/i2c-omap.c:293: warning: 'omap_i2c_idle' defined but not used
  CC      net/ipv4/ip_forward.o

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   75 +++++++++++++++++-----------------------
 1 files changed, 32 insertions(+), 43 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 801df60..4f4188d 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -269,47 +269,6 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
-static void omap_i2c_unidle(struct omap_i2c_dev *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);
-}
-
-static void omap_i2c_idle(struct omap_i2c_dev *dev)
-{
-	u16 iv;
-
-	dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
-	if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
-		omap_i2c_write_reg(dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, 1);
-	else
-		omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
-
-	if (dev->rev < OMAP_I2C_OMAP1_REV_2) {
-		iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
-	} else {
-		omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
-
-		/* Flush posted write */
-		omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
-	}
-}
-
 static int omap_i2c_init(struct omap_i2c_dev *dev)
 {
 	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
@@ -1163,8 +1122,22 @@ static int omap_i2c_runtime_suspend(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
+	u16 iv;
+
+	_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
+	if (_dev->dtrev == OMAP_I2C_IP_VERSION_2)
+		omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, 1);
+	else
+		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
+
+	if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
+		iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
+	} else {
+		omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
 
-	omap_i2c_idle(_dev);
+		/* Flush posted write */
+		omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
+	}
 
 	return 0;
 }
@@ -1174,7 +1147,23 @@ static int omap_i2c_runtime_resume(struct device *dev)
 	struct platform_device *pdev = to_platform_device(dev);
 	struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
 
-	omap_i2c_unidle(_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);
 
 	return 0;
 }
-- 
1.7.5.4

[PATCHv9 02/10] I2C: OMAP: Fix the mismatch of pm_runtime enable and disable

[Shubhrajyoti D]

Currently the i2c driver calls the pm_runtime_enable and never
the disable. This may cause a warning when pm_runtime_enable
checks for the count match.Attempting to fix the same by calling
pm_runtime_disable in the error and the remove path.

Cc: Kevin Hilman <khilman@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 4f4188d..c851672 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1090,6 +1090,7 @@ err_unuse_clocks:
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(dev->dev);
 	iounmap(dev->base);
+	pm_runtime_disable(&pdev->dev);
 err_free_mem:
 	platform_set_drvdata(pdev, NULL);
 	kfree(dev);
@@ -1110,6 +1111,7 @@ omap_i2c_remove(struct platform_device *pdev)
 	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	pm_runtime_disable(&pdev->dev);
 	iounmap(dev->base);
 	kfree(dev);
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-- 
1.7.5.4

[PATCHv9 02/10] I2C: OMAP: Fix the mismatch of pm_runtime enable and disable

[Kevin Hilman]

Shubhrajyoti D <shubhrajyoti@ti.com> writes:

> Currently the i2c driver calls the pm_runtime_enable and never
> the disable. This may cause a warning when pm_runtime_enable
> checks for the count match.Attempting to fix the same by calling
> pm_runtime_disable in the error and the remove path.

Looks right.

Can you be more specific in the changelog about when the errors/warning
happens?  e.g. why pm_runtime_enable() is called again?  Is this on
module unload/reload?

Other than that

Acked-by: Kevin Hilman <khilman@ti.com>


> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Rajendra Nayak <rnayak@ti.com>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
>  drivers/i2c/busses/i2c-omap.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 4f4188d..c851672 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -1090,6 +1090,7 @@ err_unuse_clocks:
>  	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
>  	pm_runtime_put(dev->dev);
>  	iounmap(dev->base);
> +	pm_runtime_disable(&pdev->dev);
>  err_free_mem:
>  	platform_set_drvdata(pdev, NULL);
>  	kfree(dev);
> @@ -1110,6 +1111,7 @@ omap_i2c_remove(struct platform_device *pdev)
>  	free_irq(dev->irq, dev);
>  	i2c_del_adapter(&dev->adapter);
>  	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	pm_runtime_disable(&pdev->dev);
>  	iounmap(dev->base);
>  	kfree(dev);
>  	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);

[PATCHv9 02/10] I2C: OMAP: Fix the mismatch of pm_runtime enable and disable

[Shubhrajyoti]

On Saturday 26 May 2012 03:27 AM, Kevin Hilman wrote:
> Looks right.
>
> Can you be more specific in the changelog about when the errors/warning
> happens?
By the way the count cribs Unbalanced pm_runtime_enable!
is what happens.

I found it by review, I did the testing with this patch.

Since there was an access without get_sync I was seeing
some other issues.

Did not test with the fix and without this patch.
>   e.g. why pm_runtime_enable() is called again?  Is this on
> module unload/reload?
>
> Other than that
>
> Acked-by: Kevin Hilman <khilman@ti.com>
Thanks.

[PATCHv9 03/10] I2C: OMAP: Fix the interrupt clearing in OMAP4

[Shubhrajyoti D]

On OMAP4 we were writing 1 to IRQENABLE_CLR which cleared only
the arbitration lost interrupt. The patch intends to fix the same by writing 0
to the IE register clearing all interrupts.

This is based on the work done by Vikram Pandita <vikram.pandita@ti.com>.

The  changes from the original patch ...
-  Does not use the IRQENABLE_CLR register to clear as it is not mentioned
  to be legacy register IRQENABLE_CLR helps in  atomically
  setting/clearing specific interrupts, instead use the OMAP_I2C_IE_REG as we
  are clearing all interrupts.

Cc: Vikram Pandita <vikram.pandita@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index c851672..bf07ffd 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1127,10 +1127,8 @@ static int omap_i2c_runtime_suspend(struct device *dev)
 	u16 iv;
 
 	_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
-	if (_dev->dtrev == OMAP_I2C_IP_VERSION_2)
-		omap_i2c_write_reg(_dev, OMAP_I2C_IP_V2_IRQENABLE_CLR, 1);
-	else
-		omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
+
+	omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
 
 	if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
 		iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
-- 
1.7.5.4

[PATCHv9 04/10] I2C: OMAP: Prevent the register access after pm_runtime_put in probe

[Shubhrajyoti D]

Currently in probe
pm_runtime_put(dev->dev);

...
        /* i2c device drivers may be active on return from add_adapter() */
        adap->nr = pdev->id;
        r = i2c_add_numbered_adapter(adap);
        if (r) {
                dev_err(dev->dev, "failure adding adapter\n");
                goto err_free_irq;
        }
...

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);

This may access the i2c registers without the clocks in the error cases.
Fix the same by moving the pm_runtime_put after the error check.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index bf07ffd..1777d79 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1061,8 +1061,6 @@ omap_i2c_probe(struct platform_device *pdev)
 	dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
 		 dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
 
-	pm_runtime_put(dev->dev);
-
 	adap = &dev->adapter;
 	i2c_set_adapdata(adap, dev);
 	adap->owner = THIS_MODULE;
@@ -1082,6 +1080,8 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	of_i2c_register_devices(adap);
 
+	pm_runtime_put(dev->dev);
+
 	return 0;
 
 err_free_irq:
-- 
1.7.5.4

[PATCHv9 05/10] I2C: OMAP: Don't check if wait_for_completion_timeout() returns less than zero

[Shubhrajyoti D]

By definition, wait_for_completion_timeout() returns an unsigned value and
therefore, it is not necessary to check if the return value is less than zero
as this is not possible.

This is based on a patch from Jon Hunter <jon-hunter@ti.com>
Changes from his patch
- Declare a long as the wait_for_completion_timeout returns long.

Original patch is
http://git.omapzoom.org/?p=kernel/omap.git;a=commitdiff;h=ea02cece7b0000bc736e60c4188a11aaa74bc6e6

Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 1777d79..fec8d5c 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -473,7 +473,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 			     struct i2c_msg *msg, int stop)
 {
 	struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
-	int r;
+	unsigned long timeout;
 	u16 w;
 
 	dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
@@ -541,12 +541,10 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	 * REVISIT: We should abort the transfer on signals, but the bus goes
 	 * into arbitration and we're currently unable to recover from it.
 	 */
-	r = wait_for_completion_timeout(&dev->cmd_complete,
-					OMAP_I2C_TIMEOUT);
+	timeout = wait_for_completion_timeout(&dev->cmd_complete,
+						OMAP_I2C_TIMEOUT);
 	dev->buf_len = 0;
-	if (r < 0)
-		return r;
-	if (r == 0) {
+	if (timeout == 0) {
 		dev_err(dev->dev, "controller timed out\n");
 		omap_i2c_init(dev);
 		return -ETIMEDOUT;
-- 
1.7.5.4

[PATCHv9 06/10] I2C: OMAP: Fix the crash in i2c remove

[Shubhrajyoti D]

    In omap_i2c_remove we are accessing the I2C_CON register without
    enabling the clocks. Fix the same by enabling the clocks and disabling
    it.
    This fixes the following crash.
    [  154.723022] ------------[ cut here ]------------
    [  154.725677] WARNING: at arch/arm/mach-omap2/omap_l3_noc.c:112 l3_interrupt_handler+0x1b4/0x1c4()
    [  154.725677] L3 custom error: MASTER:MPU TARGET:L4 PER2
    [  154.742614] Modules linked in: i2c_omap(-)
    [  154.746948] Backtrace:
    [  154.746948] [<c0013078>] (dump_backtrace+0x0/0x110) from [<c026c158>] (dump_stack+0x18/0x1c)
    [  154.752716]  r6:00000070 r5:c002c43c r4:df9b9e98 r3:df9b8000
    [  154.764465] [<c026c140>] (dump_stack+0x0/0x1c) from [<c0041a2c>] (warn_slowpath_common+0x5c/0x6c)
    [  154.768341] [<c00419d0>] (warn_slowpath_common+0x0/0x6c) from [<c0041ae0>] (warn_slowpath_fmt+0x38/0x40)
    [  154.776153]  r8:00000180 r7:c0361594 r6:c0379b48 r5:00080003 r4:e0838b00
    [  154.790771] r3:00000009
    [  154.791778] [<c0041aa8>] (warn_slowpath_fmt+0x0/0x40) from [<c002c43c>] (l3_interrupt_handler+0x1b4/0x1c4)
    [  154.803710]  r3:c0361598 r2:c02ef74c
    [  154.807403] [<c002c288>] (l3_interrupt_handler+0x0/0x1c4) from [<c0085f44>] (handle_irq_event_percpu+0x58/0
    [  154.818237]  r8:0000002a r7:00000000 r6:00000000 r5:df808054 r4:df8893c0
    [  154.825378] [<c0085eec>] (handle_irq_event_percpu+0x0/0x188) from [<c00860b8>] (handle_irq_event+0x44/0x64)
    [  154.835662] [<c0086074>] (handle_irq_event+0x0/0x64) from [<c0088ec0>] (handle_fasteoi_irq+0xa4/0x10c)
    [  154.845458]  r6:0000002a r5:df808054 r4:df808000 r3:c034a150
    [  154.846466] [<c0088e1c>] (handle_fasteoi_irq+0x0/0x10c) from [<c0085ed0>] (generic_handle_irq+0x30/0x38)
    [  154.854278]  r5:c034aa48 r4:0000002a
    [  154.862091] [<c0085ea0>] (generic_handle_irq+0x0/0x38) from [<c000fd38>] (handle_IRQ+0x60/0xc0)
    [  154.874450]  r4:c034ea70 r3:000001f8
    [  154.878234] [<c000fcd8>] (handle_IRQ+0x0/0xc0) from [<c0008478>] (gic_handle_irq+0x20/0x5c)
    [  154.887023]  r7:ffffff40 r6:df9b9fb0 r5:c034e2b4 r4:0000001a
    [  154.887054] [<c0008458>] (gic_handle_irq+0x0/0x5c) from [<c000ea80>] (__irq_usr+0x40/0x60)
    [  154.901153] Exception stack(0xdf9b9fb0 to 0xdf9b9ff8)
    [  154.907104] 9fa0:                                     beaf1f04 4006be00 0000000f 0000000c
    [  154.915710] 9fc0: 4006c000 00000000 00008034 ffffff40 00000007 00000000 00000000 0007b8d7
    [  154.916778] 9fe0: 00000000 beaf1b68 0000d23c 4005baf0 80000010 ffffffff
    [  154.931335]  r6:ffffffff r5:80000010 r4:4005baf0 r3:beaf1f04
    [  154.937316] ---[ end trace 1b75b31a2719ed21 ]--

Cc: Kevin Hilman <khilman@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index fec8d5c..44e8cfa 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1108,7 +1108,9 @@ omap_i2c_remove(struct platform_device *pdev)
 
 	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
+	pm_runtime_get_sync(&pdev->dev);
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	iounmap(dev->base);
 	kfree(dev);
-- 
1.7.5.4

[PATCHv9 06/10] I2C: OMAP: Fix the crash in i2c remove

[Wolfram Sang]

On Wed, May 02, 2012 at 08:02:11PM +0530, Shubhrajyoti D wrote:
>     In omap_i2c_remove we are accessing the I2C_CON register without
>     enabling the clocks. Fix the same by enabling the clocks and disabling
>     it.
>     This fixes the following crash.
>     [  154.723022] ------------[ cut here ]------------
>     [  154.725677] WARNING: at arch/arm/mach-omap2/omap_l3_noc.c:112 l3_interrupt_handler+0x1b4/0x1c4()
>     [  154.725677] L3 custom error: MASTER:MPU TARGET:L4 PER2
>     [  154.742614] Modules linked in: i2c_omap(-)
>     [  154.746948] Backtrace:
>     [  154.746948] [<c0013078>] (dump_backtrace+0x0/0x110) from [<c026c158>] (dump_stack+0x18/0x1c)
>     [  154.752716]  r6:00000070 r5:c002c43c r4:df9b9e98 r3:df9b8000
>     [  154.764465] [<c026c140>] (dump_stack+0x0/0x1c) from [<c0041a2c>] (warn_slowpath_common+0x5c/0x6c)
>     [  154.768341] [<c00419d0>] (warn_slowpath_common+0x0/0x6c) from [<c0041ae0>] (warn_slowpath_fmt+0x38/0x40)
>     [  154.776153]  r8:00000180 r7:c0361594 r6:c0379b48 r5:00080003 r4:e0838b00
>     [  154.790771] r3:00000009
>     [  154.791778] [<c0041aa8>] (warn_slowpath_fmt+0x0/0x40) from [<c002c43c>] (l3_interrupt_handler+0x1b4/0x1c4)
>     [  154.803710]  r3:c0361598 r2:c02ef74c
>     [  154.807403] [<c002c288>] (l3_interrupt_handler+0x0/0x1c4) from [<c0085f44>] (handle_irq_event_percpu+0x58/0
>     [  154.818237]  r8:0000002a r7:00000000 r6:00000000 r5:df808054 r4:df8893c0
>     [  154.825378] [<c0085eec>] (handle_irq_event_percpu+0x0/0x188) from [<c00860b8>] (handle_irq_event+0x44/0x64)
>     [  154.835662] [<c0086074>] (handle_irq_event+0x0/0x64) from [<c0088ec0>] (handle_fasteoi_irq+0xa4/0x10c)
>     [  154.845458]  r6:0000002a r5:df808054 r4:df808000 r3:c034a150
>     [  154.846466] [<c0088e1c>] (handle_fasteoi_irq+0x0/0x10c) from [<c0085ed0>] (generic_handle_irq+0x30/0x38)
>     [  154.854278]  r5:c034aa48 r4:0000002a
>     [  154.862091] [<c0085ea0>] (generic_handle_irq+0x0/0x38) from [<c000fd38>] (handle_IRQ+0x60/0xc0)
>     [  154.874450]  r4:c034ea70 r3:000001f8
>     [  154.878234] [<c000fcd8>] (handle_IRQ+0x0/0xc0) from [<c0008478>] (gic_handle_irq+0x20/0x5c)
>     [  154.887023]  r7:ffffff40 r6:df9b9fb0 r5:c034e2b4 r4:0000001a
>     [  154.887054] [<c0008458>] (gic_handle_irq+0x0/0x5c) from [<c000ea80>] (__irq_usr+0x40/0x60)
>     [  154.901153] Exception stack(0xdf9b9fb0 to 0xdf9b9ff8)
>     [  154.907104] 9fa0:                                     beaf1f04 4006be00 0000000f 0000000c
>     [  154.915710] 9fc0: 4006c000 00000000 00008034 ffffff40 00000007 00000000 00000000 0007b8d7
>     [  154.916778] 9fe0: 00000000 beaf1b68 0000d23c 4005baf0 80000010 ffffffff
>     [  154.931335]  r6:ffffffff r5:80000010 r4:4005baf0 r3:beaf1f04
>     [  154.937316] ---[ end trace 1b75b31a2719ed21 ]--
> 
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Rajendra Nayak <rnayak@ti.com>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>

I'd really like a comment from the PM experts if each and every driver
has to ensure that the clocks are enabled on remove like this?

> ---
>  drivers/i2c/busses/i2c-omap.c |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index fec8d5c..44e8cfa 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -1108,7 +1108,9 @@ omap_i2c_remove(struct platform_device *pdev)
>  
>  	free_irq(dev->irq, dev);
>  	i2c_del_adapter(&dev->adapter);
> +	pm_runtime_get_sync(&pdev->dev);
>  	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
> +	pm_runtime_put(&pdev->dev);
>  	pm_runtime_disable(&pdev->dev);
>  	iounmap(dev->base);
>  	kfree(dev);
> -- 
> 1.7.5.4
> 

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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[PATCHv9 06/10] I2C: OMAP: Fix the crash in i2c remove

[Shubhrajyoti]

On Saturday 12 May 2012 11:40 PM, Wolfram Sang wrote:
>> Cc: Kevin Hilman <khilman@ti.com>
>> > Cc: Rajendra Nayak <rnayak@ti.com>
>> > Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> I'd really like a comment from the PM experts if each and every driver
> has to ensure that the clocks are enabled on remove like this?
Just resent cc ing linux-pm

BTW also found that

Some others are also doing the same. eg:
 
drivers/mmc/host/omap_hsmmc.c
static int __devexit omap_hsmmc_remove(struct platform_device *pdev)
{
        struct omap_hsmmc_host *host = platform_get_drvdata(pdev);
        struct resource *res;

        pm_runtime_get_sync(host->dev);
        mmc_remove_host(host->mmc);

2. drivers/usb/musb/musb_core.c

static void musb_shutdown(struct platform_device *pdev)
{
        struct musb     *musb = dev_to_musb(&pdev->dev);
        unsigned long   flags;

        pm_runtime_get_sync(musb->controller);

Anyways will wait for feedback.




>
>> > ---
>> >  drivers/i2c/busses/i2c-omap.c |   

[PATCHv9 06/10] I2C: OMAP: Fix the crash in i2c remove

[Kevin Hilman]

Hi Wolfram,

Wolfram Sang <w.sang@pengutronix.de> writes:

> On Wed, May 02, 2012 at 08:02:11PM +0530, Shubhrajyoti D wrote:
>>     In omap_i2c_remove we are accessing the I2C_CON register without
>>     enabling the clocks. Fix the same by enabling the clocks and disabling
>>     it.

[...]

> I'd really like a comment from the PM experts if each and every driver
> has to ensure that the clocks are enabled on remove like this?

Yes, this is correct.

In fact, this is the goal of runtime PM.  The driver itself tells the PM
core (using runtime PM) when the device needs to be accessible and when
it doesn't.

Technically speaking, the it's up to the platform-specific runtime PM
implementation to decide whether or not the clocks are actually disable
or not  (e.g. due to wakeup latency requirements, it might decide not to
cut clocks.)

Because of that, the changelog should be reworded to say something like
"ensure device is accessible" instead of "enable the clocks", because
the runtime PM implementation does more than just manage clocks.

Kevin

P.S. It's great to see you helping out maintaining i2c drivers.  Thanks!

P.P.S. Before you merge this, I would strongly recommend we wait for a
       few more Tested-bys, and a bit more description about how this
       was tested.  We've been having quite a few problems with
       regressions introduced in OMAP drivers that have not been well
       reviewed or tested.

[PATCHv9 07/10] I2C: OMAP: Handle error check for pm runtime

[Shubhrajyoti D]

If PM runtime get_sync fails return with the error
so that no further reads/writes goes through the interface.
This will avoid possible abort. Add a error message in case
of failure with the cause of the failure.

Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 44e8cfa..a72874e 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -585,7 +585,9 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 	int i;
 	int r;
 
-	pm_runtime_get_sync(dev->dev);
+	r = pm_runtime_get_sync(dev->dev);
+	if (r < 0)
+		return r;
 
 	r = omap_i2c_wait_for_bb(dev);
 	if (r < 0)
@@ -1011,7 +1013,9 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->regs = (u8 *)reg_map_ip_v1;
 
 	pm_runtime_enable(dev->dev);
-	pm_runtime_get_sync(dev->dev);
+	r = pm_runtime_get_sync(dev->dev);
+	if (r < 0)
+		goto err_free_mem;
 
 	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 
@@ -1103,12 +1107,16 @@ omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
 	struct resource		*mem;
+	int ret;
 
 	platform_set_drvdata(pdev, NULL);
 
 	free_irq(dev->irq, dev);
 	i2c_del_adapter(&dev->adapter);
-	pm_runtime_get_sync(&pdev->dev);
+	ret = pm_runtime_get_sync(&pdev->dev);
+	if (ret < 0)
+		return ret;
+
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
-- 
1.7.5.4

[PATCHv9 07/10] I2C: OMAP: Handle error check for pm runtime

[Kevin Hilman]

Shubhrajyoti D <shubhrajyoti@ti.com> writes:

> If PM runtime get_sync fails return with the error
> so that no further reads/writes goes through the interface.
> This will avoid possible abort. Add a error message in case
> of failure with the cause of the failure.
>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
>  drivers/i2c/busses/i2c-omap.c |   14 +++++++++++---
>  1 files changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 44e8cfa..a72874e 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -585,7 +585,9 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
>  	int i;
>  	int r;
>  
> -	pm_runtime_get_sync(dev->dev);
> +	r = pm_runtime_get_sync(dev->dev);
> +	if (r < 0)
> +		return r;

nit: please use IS_ERR_VALUE() 

Kevin

[PATCHv9 07/10] I2C: OMAP: Handle error check for pm runtime

[Shubhrajyoti]

On Saturday 26 May 2012 03:36 AM, Kevin Hilman wrote:
>> +	r = pm_runtime_get_sync(dev->dev);
>> > +	if (r < 0)
>> > +		return r;
> nit: please use IS_ERR_VALUE() 
Will fix that and resend.
> Kevin

[PATCHv9 08/10] I2C: OMAP: prevent the overwrite of the errata flags

[Shubhrajyoti D]

From: Tasslehoff Kjappfot <tasskjapp@gmail.com>

i2c_probe set the dev->errata flag, but omap_i2c_init cleared the flag again.
Prevent the overwrite of the errata flags.Move the errata handling to a unified
place in probe to prevent such errors. Thus preventing the overwrite of erratum
1p153.

Signed-off-by: Tasslehoff Kjappfot <tasskjapp@gmail.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index a72874e..43b0efb 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -427,11 +427,6 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 	/* Take the I2C module out of reset: */
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
 
-	dev->errata = 0;
-
-	if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
-		dev->errata |= I2C_OMAP_ERRATA_I207;
-
 	/* Enable interrupts */
 	dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
 			OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
@@ -1019,6 +1014,11 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 
+	dev->errata = 0;
+
+	if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
+		dev->errata |= I2C_OMAP_ERRATA_I207;
+
 	if (dev->rev <= OMAP_I2C_REV_ON_3430)
 		dev->errata |= I2C_OMAP3_1P153;
 
-- 
1.7.5.4

[PATCHv9 09/10] I2C: OMAP: Do not set the XUDF(Transmit underflow) if the underflow is not reached

[Shubhrajyoti D]

Currently in the 1.153 errata handling while waiting for transmitter
underflow if NACK is got the XUDF(Transmit underflow) flag is also set.
The flag is set after wait for the condition is over.

Cc: Alexander Shishkin <virtuoso@slind.org>
Acked-by: Moiz Sonasath <m-sonasath@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 43b0efb..c0aa16b 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -730,7 +730,6 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
 			omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
 							OMAP_I2C_STAT_XDR));
-			*err |= OMAP_I2C_STAT_XUDF;
 			return -ETIMEDOUT;
 		}
 
@@ -743,6 +742,7 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 		return 0;
 	}
 
+	*err |= OMAP_I2C_STAT_XUDF;
 	return 0;
 }
 
-- 
1.7.5.4

[PATCHv9 09/10] I2C: OMAP: Do not set the XUDF(Transmit underflow) if the underflow is not reached

[Kevin Hilman]

Shubhrajyoti D <shubhrajyoti@ti.com> writes:

> Currently in the 1.153 errata handling while waiting for transmitter
> underflow if NACK is got the XUDF(Transmit underflow) flag is also set.

-EOVERFLOW

This sentence needs a rewrite and some punctuation.  It does not read well.

> The flag is set after wait for the condition is over.
>
> Cc: Alexander Shishkin <virtuoso@slind.org>
> Acked-by: Moiz Sonasath <m-sonasath@ti.com>
> Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
> ---
>  drivers/i2c/busses/i2c-omap.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 43b0efb..c0aa16b 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -730,7 +730,6 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
>  		if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
>  			omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
>  							OMAP_I2C_STAT_XDR));
> -			*err |= OMAP_I2C_STAT_XUDF;
>  			return -ETIMEDOUT;
>  		}
>  
> @@ -743,6 +742,7 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
>  		return 0;
>  	}
>  
> +	*err |= OMAP_I2C_STAT_XUDF;
>  	return 0;
>  }

Kevin

[PATCHv9 10/10] I2C: OMAP: Rename the 1p153 to the erratum id i462

[Shubhrajyoti D]

The section number in the recent errata document has changed.
Rename the erratum 1p153 to the unique id i462 instead, so that
it is easier to reference. Also change the function name and comments
to reflect the same.

Cc: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
---
 drivers/i2c/busses/i2c-omap.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index c0aa16b..0f536b2 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -173,7 +173,7 @@ enum {
 
 /* Errata definitions */
 #define I2C_OMAP_ERRATA_I207		(1 << 0)
-#define I2C_OMAP3_1P153			(1 << 1)
+#define I2C_OMAP_ERRATA_I462		(1 << 1)
 
 struct omap_i2c_dev {
 	struct device		*dev;
@@ -718,11 +718,11 @@ omap_i2c_omap1_isr(int this_irq, void *dev_id)
 #endif
 
 /*
- * OMAP3430 Errata 1.153: When an XRDY/XDR is hit, wait for XUDF before writing
+ * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
  * 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_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
 {
 	unsigned long timeout = 10000;
 
@@ -881,8 +881,8 @@ complete:
 					break;
 				}
 
-				if ((dev->errata & I2C_OMAP3_1P153) &&
-				    errata_omap3_1p153(dev, &stat, &err))
+				if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
+				    errata_omap3_i462(dev, &stat, &err))
 					goto complete;
 
 				omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
@@ -1020,7 +1020,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->errata |= I2C_OMAP_ERRATA_I207;
 
 	if (dev->rev <= OMAP_I2C_REV_ON_3430)
-		dev->errata |= I2C_OMAP3_1P153;
+		dev->errata |= I2C_OMAP_ERRATA_I462;
 
 	if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
 		u16 s;
-- 
1.7.5.4

[PATCHv9 00/10] I2C fixes

[Wolfram Sang]

On Wed, May 02, 2012 at 08:02:05PM +0530, Shubhrajyoti D wrote:
> 
> The patch series does the following
> 
> - Warn fixes if CONFIG_PM_RUNTIME is not selected.
> - In case of i2c remove register access was done without any
>  get_sync fix the same.
> - Folds a patch from Tasslehoff to prevent any merge conflicts.
> - Prevents the XDUF flag to be set if the underflow condition is not met.
> - As per discussion in [1] .Adds a patch to rename the 1p153 errata and
>  use the unique id instead as the section number in the recent errata
>  docs has changed.
> 
> v9:
> Fix the comments from Wolfram Sang

Patch 2 has my comment not addressed, so I stopped reviewing. It is
probably more helpful (and easier for me, too) if you do a changelog per
patch (and not of the whole series), then you can immediately see if
that specific changelog matches the current patch. 'git send-email
--annotate' might be helpful here.

Thanks,

   Wolfram

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
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[PATCHv9 00/10] I2C fixes

[Kevin Hilman]

Shubhrajyoti D <shubhrajyoti@ti.com> writes:

> The patch series does the following
>
> - Warn fixes if CONFIG_PM_RUNTIME is not selected.
> - In case of i2c remove register access was done without any
>  get_sync fix the same.
> - Folds a patch from Tasslehoff to prevent any merge conflicts.
> - Prevents the XDUF flag to be set if the underflow condition is not met.
> - As per discussion in [1] .Adds a patch to rename the 1p153 errata and
>  use the unique id instead as the section number in the recent errata
>  docs has changed.
>
> v9:
> Fix the comments from Wolfram Sang
>
> [1] http://www.spinics.net/lists/linux-i2c/msg07607.html
>
> Tested on omap4sdp and omap3sdp.

Can you also describe how it was tested?  

With the runtime PM changes, does it still hit full-chip retention in
idle and suspend after these changes?

I had a few minor comments on this version, otherwise feel free add

Reviewed-by: Kevin Hilman <khilman@ti.com>

That being said, before this is merged, I woudl like to see some more
non-author Tested-bys.  We've been having lots of regressions of late
from OMAP drivers that are not being sufficiently tested before
merging.  We need to ensure proper testing before merge.

Other testers should also report what platforms they tested on, and how
it was tested.

Thanks,

Kevin

[PATCHv9 00/10] I2C fixes

[Shubhrajyoti]

Hi Kevin,


On Saturday 26 May 2012 03:43 AM, Kevin Hilman wrote:
> Shubhrajyoti D <shubhrajyoti@ti.com> writes:
>
>> The patch series does the following
>>
>> - Warn fixes if CONFIG_PM_RUNTIME is not selected.
>> - In case of i2c remove register access was done without any
>>  get_sync fix the same.
>> - Folds a patch from Tasslehoff to prevent any merge conflicts.
>> - Prevents the XDUF flag to be set if the underflow condition is not met.
>> - As per discussion in [1] .Adds a patch to rename the 1p153 errata and
>>  use the unique id instead as the section number in the recent errata
>>  docs has changed.
>>
>> v9:
>> Fix the comments from Wolfram Sang
>>
>> [1] http://www.spinics.net/lists/linux-i2c/msg07607.html
>>
>> Tested on omap4sdp and omap3sdp.
> Can you also describe how it was tested?  
I did basic functionality  tests using i2c-tools.
>
> With the runtime PM changes, does it still hit full-chip retention in
> idle and suspend after these changes?
Will check.
>
> I had a few minor comments on this version,
Will fixup and resend.
>  otherwise feel free add
>
> Reviewed-by: Kevin Hilman <khilman@ti.com>
Thanks for your review.
>
> That being said, before this is merged, I woudl like to see some more
> non-author Tested-bys.  We've been having lots of regressions of late
> from OMAP drivers that are not being sufficiently tested before
> merging.  We need to ensure proper testing before merge.
>
> Other testers should also report what platforms they tested on, and how
> it was tested.
>
> Thanks,
>
> Kevin

[PATCHv9 00/10] I2C fixes

[Kevin Hilman]

+Neil Brown

Shubhrajyoti D <shubhrajyoti@ti.com> writes:

> The patch series does the following
>
> - Warn fixes if CONFIG_PM_RUNTIME is not selected.
> - In case of i2c remove register access was done without any
>  get_sync fix the same.
> - Folds a patch from Tasslehoff to prevent any merge conflicts.
> - Prevents the XDUF flag to be set if the underflow condition is not met.
> - As per discussion in [1] .Adds a patch to rename the 1p153 errata and
>  use the unique id instead as the section number in the recent errata
>  docs has changed.
>

Shubhrajyoti,

Can you add one more patch to this series.

The patch below from Neil Brown has been circulating for awhile, and
I've been using it locally for awhile now too.  It would help if it got
into this series and got some broader testing.

Thanks,

Kevin


>From 0c6effd8356e6273c294490a576551ef37ae6799 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Fri, 30 Dec 2011 12:40:30 +1100
Subject: [PATCH] OMAP/I2C - Fix timeout problem during suspend.

On a board with OMAP3 processor and TWL4030 Power management,
we need to talk to the TWL4030 during late suspend but cannot
because the I2C interrupt is disabled (as late suspend disables
interrupt).

e.g. I get messages like:

[   62.161102] musb-omap2430 musb-omap2430: LATE power domain suspend
[   63.167205] omap_i2c omap_i2c.1: controller timed out
[   63.183044] twl: i2c_read failed to transfer all messages
[   64.182861] omap_i2c omap_i2c.1: controller timed out
[   64.198455] twl: i2c_write failed to transfer all messages
[   65.198455] omap_i2c omap_i2c.1: controller timed out
[   65.203765] twl: i2c_write failed to transfer all messages

The stack shows omap2430_runtime_suspend calling twl4030_set_suspend
which tries to power-down the USB PHY (twl4030_phy_suspend ->
twl4030_phy_power -> __twl4030_phy_power which as a nice WARN_ON
that helps).

Then we get the same in resume:

[   69.603912] musb-omap2430 musb-omap2430: EARLY power domain resume
[   70.610473] omap_i2c omap_i2c.1: controller timed out
[   70.626129] twl: i2c_write failed to transfer all messages
etc.

So don't disable interrupts for I2C.

Acked-by: Kevin Hilman <khilman@ti.com>
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: NeilBrown <neilb@suse.de>
---
 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 801df60..e024c50 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -1092,7 +1092,7 @@ 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 = request_irq(dev->irq, isr, IRQF_NO_SUSPEND, pdev->name, dev);
 
 	if (r) {
 		dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
-- 
1.7.9.2

[PATCHv9 00/10] I2C fixes

[Shubhrajyoti]

On Saturday 26 May 2012 05:10 AM, Kevin Hilman wrote:
> Shubhrajyoti,
>
> Can you add one more patch to this series.
Yes will add it.

Thanks,
Shubhro
>
> The patch below from Neil Brown has been circulating for awhile, and
> I've been using it locally for awhile now too.  It would help if it got
> into this series and got some broader testing.
>
> Thanks,
>
> Kevin