I2C fixes

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

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

---
 drivers/i2c/busses/i2c-omap.c |   75 +++++++++++++++++-----------------------
 1 files changed, 32 insertions(+), 43 deletions(-)

index 801df60..4f4188d 100644
@@ -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

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.

---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

index 4f4188d..c851672 100644
@@ -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

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

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.

Thanks.

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 <[email protected]>.

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.

---
 drivers/i2c/busses/i2c-omap.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

index c851672..bf07ffd 100644
@@ -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

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.

---
 drivers/i2c/busses/i2c-omap.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

index bf07ffd..1777d79 100644
@@ -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

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 <[email protected]> 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

---
 drivers/i2c/busses/i2c-omap.c |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)

index 1777d79..fec8d5c 100644
@@ -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

    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 ]--

---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

index fec8d5c..44e8cfa 100644
@@ -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

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?

Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120512/8e44dbae/attachment.sig>

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.

Hi Wolfram,

[...]

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.

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.

---
 drivers/i2c/busses/i2c-omap.c |   14 +++++++++++---
 1 files changed, 11 insertions(+), 3 deletions(-)

index 44e8cfa..a72874e 100644
@@ -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

Will fix that and resend.

From: Tasslehoff Kjappfot <[email protected]>

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.

---
 drivers/i2c/busses/i2c-omap.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

index a72874e..43b0efb 100644
@@ -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

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.

---
 drivers/i2c/busses/i2c-omap.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

index 43b0efb..c0aa16b 100644
@@ -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

-EOVERFLOW

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

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.

---
 drivers/i2c/busses/i2c-omap.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

index c0aa16b..0f536b2 100644
@@ -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

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/  |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: Digital signature
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120512/c4db5ea4/attachment.sig>

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

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

Hi Kevin,

I did basic functionality tests using i2c-tools.

Will check.

Will fixup and resend.

Thanks for your review.

+Neil Brown

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: NeilBrown <[email protected]>
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.

---
 drivers/i2c/busses/i2c-omap.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 801df60..e024c50 100644
@@ -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

Yes will add it.

Thanks,
Shubhro