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I2C Updates

PATCH Superseded Shubhrajyoti D 4 participants 26 messages Apr 12, 2012 – Apr 20, 2012 1 message not in the archive

Subsystems (6)
Arm (32-bit) Arm sub-architectures I2C subsystem host drivers OMAP2+ support +2 more subsystems

v8 of 10 Superseded Latest is v10 →

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Shubhrajyoti D

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#0 lore raw

v8 cover I2C Updates

The patch series does the following

- Warn fixes if CONFIG_PM_RUNTIME is not selected.
- I2C register restore only if context if the context is lost
- Bus busy recovery mechanism.
- the reset is not done in init.
- Adds a patch to use devm_* functions
- Also checks the return type of the get_sync and in case
of errors prevents register access, also print the cause of failure in case of errors.
- In case of i2c remove register access was done without any get_sync fix the same.
- Adds a pdata function pointer to do context save restore
- Split the omap_i2c_isr to increase readability
- Make the i2c use SET_RUNTIME_PM_OPS
- 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.

- As discussed in [2], Paul has queued the flag for context restore patch, removing it from the series.

v8
Fix Felipe's comments and use devm_request_and_ioremap.

[1] http://www.spinics.net/lists/linux-i2c/msg07607.html
[2] http://www.spinics.net/lists/linux-i2c/msg07685.html

Tested on omap4sdp and omap3sdp.

The following changes since commit 258f742635360175564e9470eb060ff4d4b984e7:

modpost: Fix modpost license checking of vmlinux.o (2012-04-09 20:52:56 -0700)

are available in the git repository at:
git://gitorious.org/linus-tree/linus-tree.git i2c_omap-next

Jon Hunter (1):
I2C: OMAP: Correct I2C revision for OMAP3

Shubhrajyoti D (15):
I2C: OMAP: make omap_i2c_unidle/idle functions depend on
CONFIG_PM_RUNTIME
I2C: OMAP: Remove reset at init
I2C: OMAP: I2C register restore only if context is lost
I2C: OMAP: Fix the interrupt clearing in OMAP4
I2C: OMAP: Fix the mismatch of pm_runtime enable and disable
I2C: OMAP: Optimise the remove code
I2C: OMAP: Fix the error handling
I2C: OMAP: Don't check if wait_for_completion_timeout() returns less
than zero
I2C: OMAP: use devm_* functions
I2C: OMAP: Fix the crash in i2c remove
I2C: OMAP: Handle error check for pm runtime
I2C: OMAP: Use SET_RUNTIME_PM_OPS
I2C: OMAP: make the read ready processing a separate function
I2C: OMAP: Do not set the XUDF if the underflow is not reached
I2C: OMAP: Rename the 1p153 to the erratum id i462

Tasslehoff Kjappfot (1):
I2C: OMAP: fix missing handling of errata I2C_OMAP3_1P153

Vikram Pandita (1):
I2C: OMAP: Recover from Bus Busy condition

 arch/arm/plat-omap/i2c.c      |    3 +
 drivers/i2c/busses/i2c-omap.c |  350 +++++++++++++++++++++++------------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 199 insertions(+), 155 deletions(-)
Signature · 1 line
1.7.4.1
author
#1 lore raw

PATCH v8 1/18 I2C: OMAP: make omap_i2c_unidle/idle functions depend on CONFIG_PM_RUNTIME

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 <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   75 +++++++++++++++++-----------------------
 1 files changed, 32 insertions(+), 43 deletions(-)
drivers/i2c/busses/i2c-omap.c +32 -43
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;
 }
Signature · 1 line
1.7.4.1
author
#2 lore raw

PATCH v8 2/18 I2C: OMAP: Remove reset at init

In reply to Shubhrajyoti D

The reset in the driver at init is not needed anymore as the following patch has removed the HWMOD_INIT_NO_RESET flag. 6d3c55f [OMAP: hwmod: fix the i2c-reset timeout during bootup]

This patch does the following
-removes the reset from the probe and implements a omap_i2c_reset
function to reset.
- Reset is removed from omap_i2c_init, which was called not only during probe, but also after time out and error handling. omap_i2c_reset is added in those places to effect the reset.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   20 +++++++++++++-------
 1 files changed, 13 insertions(+), 7 deletions(-)
drivers/i2c/busses/i2c-omap.c +13 -7
index 4f4188d..e402ebb 100644
@@ -269,15 +269,9 @@ static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
-static int omap_i2c_init(struct omap_i2c_dev *dev)
+static int omap_i2c_reset(struct omap_i2c_dev *dev)
 {
-	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
-	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
-	unsigned long fclk_rate = 12000000;
 	unsigned long timeout;
-	unsigned long internal_clk = 0;
-	struct clk *fclk;
-
 	if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
 		/* Disable I2C controller before soft reset */
 		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,

@@ -325,6 +319,16 @@ static int omap_i2c_init(struct omap_i2c_dev *dev)
 							dev->westate);
 		}
 	}
+}
+
+static int omap_i2c_init(struct omap_i2c_dev *dev)
+{
+	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
+	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
+	unsigned long fclk_rate = 12000000;
+	unsigned long internal_clk = 0;
+	struct clk *fclk;
+
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 
 	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {

@@ -548,6 +552,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 		return r;
 	if (r == 0) {
 		dev_err(dev->dev, "controller timed out\n");
+		omap_i2c_reset(dev);
 		omap_i2c_init(dev);
 		return -ETIMEDOUT;
 	}

@@ -558,6 +563,7 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
 	/* We have an error */
 	if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
 			    OMAP_I2C_STAT_XUDF)) {
+		omap_i2c_reset(dev);
 		omap_i2c_init(dev);
 		return -EIO;
 	}
Signature · 1 line
1.7.4.1
author
#3 lore raw

PATCH v8 3/18 I2C: OMAP: Recover from Bus Busy condition

In reply to Shubhrajyoti D

From: Vikram Pandita <[email protected]>

In case a peripheral is driving SDA bus low (ie. a start condition), provide a constant clock output using the test mode of the OMAP I2C controller to try and clear the bus. Soft reset I2C controller after attempting the bus clear to ensure that controller is in a good state.

Based upon Vikram Pandita's patch from TI Android 3.0. I acknowledge the contributions and suggestions of Jon and Hemant.

A couple differences from the original patch ...
1. Add a new function for bus clear
2. Ensure that the CON.I2C_EN bit is set when using the SYSTEST feature to output a permanent clock. This bit needs to be set and typically it would be set by the unidle function but this is not the case for all OMAP generations.
3. Program the SYSTEST setting only the bits we care about. However, restore SYSTEST registers to there original state as some OMAP generations do not implement perform a soft-reset.
4. Clear the CON register after performing the bus clear, so when we call the init function the controller is disabled and the init function will re-enable later.

Original patch can be found here:
http://git.omapzoom.org/?p=kernel/omap.git;a=commit;h=a2ab04192ba25e60f95ba1ff3af5601a2d7b5bd1

Signed-off-by Vikram Pandita <[email protected]>
Signed-off-by Jon Hunter <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   33 ++++++++++++++++++++++++++++++---
 1 files changed, 30 insertions(+), 3 deletions(-)
drivers/i2c/busses/i2c-omap.c +30 -3
index e402ebb..a882558 100644
@@ -147,16 +147,15 @@ enum {
 #define OMAP_I2C_SCLH_HSSCLH	8
 
 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
-#ifdef DEBUG
 #define OMAP_I2C_SYSTEST_ST_EN		(1 << 15)	/* System test enable */
 #define OMAP_I2C_SYSTEST_FREE		(1 << 14)	/* Free running mode */
 #define OMAP_I2C_SYSTEST_TMODE_MASK	(3 << 12)	/* Test mode select */
-#define OMAP_I2C_SYSTEST_TMODE_SHIFT	(12)		/* Test mode select */
+#define OMAP_I2C_SYSTEST_TMODE_TEST	(2 << 12)	/* Test mode select */
+#define OMAP_I2C_SYSTEST_TMODE_LOOP	(3 << 12)	/* Test mode select */
 #define OMAP_I2C_SYSTEST_SCL_I		(1 << 3)	/* SCL line sense in */
 #define OMAP_I2C_SYSTEST_SCL_O		(1 << 2)	/* SCL line drive out */
 #define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 #define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
-#endif
 
 /* OCP_SYSSTATUS bit definitions */
 #define SYSS_RESETDONE_MASK		(1 << 0)

@@ -319,6 +318,7 @@ static int omap_i2c_reset(struct omap_i2c_dev *dev)
 							dev->westate);
 		}
 	}
+	return 0;
 }
 
 static int omap_i2c_init(struct omap_i2c_dev *dev)

@@ -471,6 +471,31 @@ static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
 }
 
 /*
+ * Bus Clear
+ */
+static int omap_i2c_bus_clear(struct omap_i2c_dev *dev)
+{
+	u16 w;
+
+	/*
+	 * Per the I2C specification, if we are stuck in a bus busy state
+	 * we can attempt a bus clear to try and recover the bus by sending
+	 * at least 9 clock pulses on SCL. Put the I2C in a test mode so it
+	 * will output a continuous clock on SCL.
+	 */
+	w = omap_i2c_read_reg(dev, OMAP_I2C_SYSTEST_REG);
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+	omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, (OMAP_I2C_SYSTEST_ST_EN
+			   | OMAP_I2C_SYSTEST_TMODE_TEST));
+	msleep(1);
+	omap_i2c_write_reg(dev, OMAP_I2C_SYSTEST_REG, w);
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
+	omap_i2c_reset(dev);
+	omap_i2c_init(dev);
+	return omap_i2c_wait_for_bb(dev);
+}
+
+/*
  * Low level master read/write transaction.
  */
 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,

@@ -597,6 +622,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 
 	r = omap_i2c_wait_for_bb(dev);
 	if (r < 0)
+		r = omap_i2c_bus_clear(dev);
+	if (r < 0)
 		goto out;
 
 	if (dev->set_mpu_wkup_lat != NULL)
Signature · 1 line
1.7.4.1
author
#4 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

In reply to Shubhrajyoti D

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost. Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   52 ++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 38 insertions(+), 18 deletions(-)
arch/arm/plat-omap/i2c.c +3 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);
drivers/i2c/busses/i2c-omap.c +34 -18

103 lines not on this page · raw message

include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif
Signature · 1 line
1.7.4.1
maintainer
#5 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Quoted 18 lines · Shubhrajyoti D

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost. Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   52 ++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 38 insertions(+), 18 deletions(-)
arch/arm/plat-omap/i2c.c +0 -0
index db071bc..4ccab07 100644

arch/arm/plat-omap/i2c.c static inline int omap2_i2c_add_bus(int bus_id) · line 187

Quoted 9 lines
arch/arm/plat-omap/i2c.c +3 -0
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);

This should be acked by Kevin, adding him to Cc.

For the arch/arm/plat-omap/i2c.c part:

Acked-by Tony Lindgren <[email protected]>
Quoted 129 lines
drivers/i2c/busses/i2c-omap.c +34 -18
index a882558..45389db 100644
@@ -43,6 +43,7 @@
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
 #include <linux/pm_runtime.h>
+#include <plat/omap_device.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_OMAP1_REV_2		0x20

@@ -157,9 +158,6 @@ enum {
 #define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 #define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
 
-/* OCP_SYSSTATUS bit definitions */
-#define SYSS_RESETDONE_MASK		(1 << 0)
-
 /* OCP_SYSCONFIG bit definitions */
 #define SYSC_CLOCKACTIVITY_MASK		(0x3 << 8)
 #define SYSC_SIDLEMODE_MASK		(0x3 << 3)

@@ -184,6 +182,7 @@ struct omap_i2c_dev {
 	u32			latency;	/* maximum mpu wkup latency */
 	void			(*set_mpu_wkup_lat)(struct device *dev,
 						    long latency);
+	int			(*get_context_loss_count)(struct device *dev);
 	u32			speed;		/* Speed of bus in kHz */
 	u32			dtrev;		/* extra revision from DT */
 	u32			flags;

@@ -206,6 +205,7 @@ struct omap_i2c_dev {
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
+	int			dev_lost_count;
 };
 
 static const u8 reg_map_ip_v1[] = {

@@ -1025,6 +1025,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->speed = pdata->clkrate;
 		dev->flags = pdata->flags;
 		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+		dev->get_context_loss_count = pdata->get_context_loss_count;
 		dev->dtrev = pdata->rev;
 	}
 

@@ -1151,12 +1152,32 @@ omap_i2c_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_RUNTIME
+static void omap_i2c_restore(struct omap_i2c_dev *dev)
+{
+	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_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 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;
 
+	if (_dev->get_context_loss_count)
+		_dev->dev_lost_count = _dev->get_context_loss_count(dev);
+
 	_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);

@@ -1179,24 +1200,19 @@ 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);
+	int loss_cnt;
 
-	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);
+	if (_dev->get_context_loss_count) {
+		loss_cnt = _dev->get_context_loss_count(dev);
+		if (loss_cnt < 0)
+			return loss_cnt;
+
+		if (_dev->dev_lost_count == loss_cnt && _dev->dev_lost_count)
+			return 0;
 	}
 
-	/*
-	 * 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_restore(_dev);
 
 	return 0;
 }
include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif
Signature · 1 line
1.7.4.1
author
#6 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Quoted 14 lines · Tony Lindgren
Quoted 13 lines · Shubhrajyoti D

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost. Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   52 ++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 38 insertions(+), 18 deletions(-)
Quoted 15 lines
Quoted 5 lines
arch/arm/plat-omap/i2c.c +0 -0
index db071bc..4ccab07 100644

arch/arm/plat-omap/i2c.c static inline int omap2_i2c_add_bus(int bus_id) · line 187

Quoted 9 lines
arch/arm/plat-omap/i2c.c +3 -0
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);

This should be acked by Kevin,

I should have cced Kevin.

Quoted 1 line

adding him to Cc.

Thanks.

Quoted 4 lines

For the arch/arm/plat-omap/i2c.c part:

Acked-by Tony Lindgren <[email protected]>

Thanks.

#7 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

In reply to Shubhrajyoti D
Quoted 3 lines · Shubhrajyoti D

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost.

OK, minor comment below.

Quoted 2 lines

Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

The definition is removed, but I don't see any of the users removed. If the users were cleaned up earlier in the series, then the removal of this should be done with that, or as a separate patch. I don't see why it belongs with this patch.

Quoted 109 lines
Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   52 ++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 38 insertions(+), 18 deletions(-)
arch/arm/plat-omap/i2c.c +3 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);
drivers/i2c/busses/i2c-omap.c +25 -6
index a882558..45389db 100644
@@ -43,6 +43,7 @@
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
 #include <linux/pm_runtime.h>
+#include <plat/omap_device.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_OMAP1_REV_2		0x20

@@ -157,9 +158,6 @@ enum {
 #define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 #define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
 
-/* OCP_SYSSTATUS bit definitions */
-#define SYSS_RESETDONE_MASK		(1 << 0)
-
 /* OCP_SYSCONFIG bit definitions */
 #define SYSC_CLOCKACTIVITY_MASK		(0x3 << 8)
 #define SYSC_SIDLEMODE_MASK		(0x3 << 3)

@@ -184,6 +182,7 @@ struct omap_i2c_dev {
 	u32			latency;	/* maximum mpu wkup latency */
 	void			(*set_mpu_wkup_lat)(struct device *dev,
 						    long latency);
+	int			(*get_context_loss_count)(struct device *dev);
 	u32			speed;		/* Speed of bus in kHz */
 	u32			dtrev;		/* extra revision from DT */
 	u32			flags;

@@ -206,6 +205,7 @@ struct omap_i2c_dev {
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
+	int			dev_lost_count;
 };
 
 static const u8 reg_map_ip_v1[] = {

@@ -1025,6 +1025,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->speed = pdata->clkrate;
 		dev->flags = pdata->flags;
 		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+		dev->get_context_loss_count = pdata->get_context_loss_count;
 		dev->dtrev = pdata->rev;
 	}
 

@@ -1151,12 +1152,32 @@ omap_i2c_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_RUNTIME
+static void omap_i2c_restore(struct omap_i2c_dev *dev)
+{
+	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_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 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;
 
+	if (_dev->get_context_loss_count)
+		_dev->dev_lost_count = _dev->get_context_loss_count(dev);
+
 	_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);

@@ -1179,24 +1200,19 @@ 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);
+	int loss_cnt;
 
-	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);

drivers/i2c/busses/i2c-omap.c static int omap_i2c_runtime_resume(struct device *dev) · line 1208

Quoted 10 lines
drivers/i2c/busses/i2c-omap.c +4 -6
-		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);
+	if (_dev->get_context_loss_count) {
+		loss_cnt = _dev->get_context_loss_count(dev);
+		if (loss_cnt < 0)
+			return loss_cnt;

To avoid messing up driver state, upon error, you should probably restore context, not abort.

drivers/i2c/busses/i2c-omap.c static int omap_i2c_runtime_resume(struct device *dev) · line 1211

Quoted 2 lines
drivers/i2c/busses/i2c-omap.c +2 -0
+		if (_dev->dev_lost_count == loss_cnt && _dev->dev_lost_count)
+			return 0;

Why the non-zero check?

Seems like all you need to check is if (_dev->dev_lost_count != loss_cnt).

Kevin

Quoted 25 lines
drivers/i2c/busses/i2c-omap.c +2 -6
 	}
 
-	/*
-	 * 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_restore(_dev);
 
 	return 0;
 }
include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif
#8 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Hi Kevin,
Thanks for your review,

Quoted 8 lines · Kevin Hilman
Quoted 3 lines · Shubhrajyoti D

?Currently i2c register restore is done always. ?Adding conditional restore.
?The i2c register restore is done only if the context is lost.

OK, minor comment below.

Quoted 7 lines
Quoted 2 lines

?Also remove the definition of SYSS_RESETDONE_MASK and use the ?one in omap_hwmod.h.

The definition is removed, but I don't see any of the users removed. If the users were cleaned up earlier in the series, then the removal of this should be done with that, or as a separate patch. ?I don't see why it belongs with this patch.

I have not removed the users actually the macro was redefined. I have instead used the definition in omap_hwmod.h which gets added when I include omap_device.h

Let me know if you prefer a separate patch?

Quoted 107 lines
Quoted 107 lines
Signed-off-by Shubhrajyoti D <[email protected]>

---

?arch/arm/plat-omap/i2c.c ? ? ?| ? ?3 ++
?drivers/i2c/busses/i2c-omap.c | ? 52 ++++++++++++++++++++++++++--------------
?include/linux/i2c-omap.h ? ? ?| ? ?1 +

?3 files changed, 38 insertions(+), 18 deletions(-)

arch/arm/plat-omap/i2c.c +0 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)

? ? ? ?*/
? ? ? if (cpu_is_omap34xx())
? ? ? ? ? ? ? pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;

arch/arm/plat-omap/i2c.c +3 -0
+
+ ? ? pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+

? ? ? pdev = omap_device_build(name, bus_id, oh, pdata, ? ? ? ? ? ? ? ? ? ? ? sizeof(struct omap_i2c_bus_platform_data), ? ? ? ? ? ? ? ? ? ? ? NULL, 0, 0);

drivers/i2c/busses/i2c-omap.c +0 -0
index a882558..45389db 100644
@@ -43,6 +43,7 @@

?#include <linux/slab.h>
?#include <linux/i2c-omap.h>
?#include <linux/pm_runtime.h>
+#include <plat/omap_device.h>

?/* I2C controller revisions */
?#define OMAP_I2C_OMAP1_REV_2 ? ? ? ? 0x20

drivers/i2c/busses/i2c-omap.c +0 -0
@@ -157,9 +158,6 @@ enum {

?#define OMAP_I2C_SYSTEST_SDA_I ? ? ? ? ? ? ? (1 << 1) ? ? ? ?/* SDA line sense in */ ?#define OMAP_I2C_SYSTEST_SDA_O ? ? ? ? ? ? ? (1 << 0) ? ? ? ?/* SDA line drive out */

drivers/i2c/busses/i2c-omap.c +0 -3
-/* OCP_SYSSTATUS bit definitions */
-#define SYSS_RESETDONE_MASK ? ? ? ? ?(1 << 0)
-

?/* OCP_SYSCONFIG bit definitions */
?#define SYSC_CLOCKACTIVITY_MASK ? ? ? ? ? ? ?(0x3 << 8) ?#define SYSC_SIDLEMODE_MASK ? ? ? ? ?(0x3 << 3)

drivers/i2c/busses/i2c-omap.c +0 -0
@@ -184,6 +182,7 @@ struct omap_i2c_dev {

? ? ? u32 ? ? ? ? ? ? ? ? ? ? latency; ? ? ? ?/* maximum mpu wkup latency */ ? ? ? void ? ? ? ? ? ? ? ? ? ?(*set_mpu_wkup_lat)(struct device *dev, ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? long latency);
+ ? ? int ? ? ? ? ? ? ? ? ? ? (*get_context_loss_count)(struct device *dev); ? ? ? u32 ? ? ? ? ? ? ? ? ? ? speed; ? ? ? ? ?/* Speed of bus in kHz */ ? ? ? u32 ? ? ? ? ? ? ? ? ? ? dtrev; ? ? ? ? ?/* extra revision from DT */ ? ? ? u32 ? ? ? ? ? ? ? ? ? ? flags;

drivers/i2c/busses/i2c-omap.c +2 -0
@@ -206,6 +205,7 @@ struct omap_i2c_dev {
 ? ? ? u16 ? ? ? ? ? ? ? ? ? ? syscstate;
 ? ? ? u16 ? ? ? ? ? ? ? ? ? ? westate;
 ? ? ? u16 ? ? ? ? ? ? ? ? ? ? errata;
+ ? ? int ? ? ? ? ? ? ? ? ? ? dev_lost_count;
 ?};
 
 ?static const u8 reg_map_ip_v1[] = {

@@ -1025,6 +1025,7 @@ omap_i2c_probe(struct platform_device *pdev)
 ? ? ? ? ? ? ? dev->speed = pdata->clkrate;
 ? ? ? ? ? ? ? dev->flags = pdata->flags;
 ? ? ? ? ? ? ? dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+ ? ? ? ? ? ? dev->get_context_loss_count = pdata->get_context_loss_count;
 ? ? ? ? ? ? ? dev->dtrev = pdata->rev;
 ? ? ? }
 

@@ -1151,12 +1152,32 @@ omap_i2c_remove(struct platform_device *pdev)
 ?}

?#ifdef CONFIG_PM_RUNTIME

drivers/i2c/busses/i2c-omap.c +17 -0
+static void omap_i2c_restore(struct omap_i2c_dev *dev)
+{
+ ? ? 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_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 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;

+ ? ? if (_dev->get_context_loss_count)
+ ? ? ? ? ? ? _dev->dev_lost_count = _dev->get_context_loss_count(dev); +
? ? ? _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);

drivers/i2c/busses/i2c-omap.c +1 -0
@@ -1179,24 +1200,19 @@ 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);
+ ? ? int loss_cnt;
Quoted 16 lines

drivers/i2c/busses/i2c-omap.c static int omap_i2c_runtime_resume(struct device *dev) · line 1208

Quoted 13 lines
drivers/i2c/busses/i2c-omap.c +4 -9
- ? ? 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);
+ ? ? if (_dev->get_context_loss_count) {
+ ? ? ? ? ? ? loss_cnt = _dev->get_context_loss_count(dev);
+ ? ? ? ? ? ? if (loss_cnt < 0)
+ ? ? ? ? ? ? ? ? ? ? return loss_cnt;

To avoid messing up driver state, upon error, you should probably restore context, not abort.

Agreed , will fix this.

Quoted 5 lines

drivers/i2c/busses/i2c-omap.c static int omap_i2c_runtime_resume(struct device *dev) · line 1210

Quoted 3 lines
drivers/i2c/busses/i2c-omap.c +2 -0
+ ? ? ? ? ? ? if (_dev->dev_lost_count == loss_cnt && _dev->dev_lost_count)
+ ? ? ? ? ? ? ? ? ? ? return 0;

Why the non-zero check?

Actually the driver probe-->omap_i2c_init

here
<snip>

                dev->pscstate = psc;
                dev->scllstate = scll;
                dev->sclhstate = sclh;
                dev->bufstate = buf;

<snip>

variables are updated and the first write happens in the handler.

Quoted 34 lines

Seems like all you need to check is if (_dev->dev_lost_count != loss_cnt).

Kevin

Quoted 24 lines
drivers/i2c/busses/i2c-omap.c +2 -6
 ? ? ? }
 
- ? ? /*
- ? ? ?* 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_restore(_dev);
 
 ? ? ? return 0;
 ?}
include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 ? ? ? u32 ? ? ? ? ? ? rev;
 ? ? ? u32 ? ? ? ? ? ? flags;
 ? ? ? void ? ? ? ? ? ?(*set_mpu_wkup_lat)(struct device *dev, long set);
+ ? ? int ? ? ? ? ? ? (*get_context_loss_count)(struct device *dev);
 ?};
Quoted 1 line

?#endif

--
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author
#9 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Hi Kevin,

Quoted 11 lines

Hi Kevin,
Thanks for your review,

Quoted 7 lines · Kevin Hilman
Quoted 3 lines · Shubhrajyoti D

?Currently i2c register restore is done always. ?Adding conditional restore.
?The i2c register restore is done only if the context is lost.

OK, minor comment below.

Thanks for the suggestion of the error case restore. Updated the patch. Also added Tony's ack for the plat part.

Quoted 1 line

From 1ca222f6f50868e07d9a46575e73dd66fd2d542e Mon Sep 17 00:00:00 2001

From: Shubhrajyoti D <[email protected]>
Date: Tue, 17 Jan 2012 16:13:03 +0530
Subject: [PATCH] I2C: OMAP: I2C register restore only if context is lost

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost or in case of error to be on the safe side.
Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

Cc Kevin Hilman <[email protected]>
[For the arch/arm/plat-omap/i2c.c part]
Acked-by Tony Lindgren <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   53 +++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 39 insertions(+), 18 deletions(-)
arch/arm/plat-omap/i2c.c +3 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);
drivers/i2c/busses/i2c-omap.c +35 -18

104 lines not on this page · raw message

include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif
Signature · 1 line
1.7.5.4
#10 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Quoted 67 lines · Shubhrajyoti

Hi Kevin,

Quoted 11 lines

Hi Kevin,
Thanks for your review,

Quoted 7 lines · Kevin Hilman
Quoted 3 lines · Shubhrajyoti D

?Currently i2c register restore is done always. ?Adding conditional restore.
?The i2c register restore is done only if the context is lost.

OK, minor comment below.

Thanks for the suggestion of the error case restore. Updated the patch. Also added Tony's ack for the plat part.

From 1ca222f6f50868e07d9a46575e73dd66fd2d542e Mon Sep 17 00:00:00 2001
From: Shubhrajyoti D <[email protected]>
Date: Tue, 17 Jan 2012 16:13:03 +0530
Subject: [PATCH] I2C: OMAP: I2C register restore only if context is lost

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost or in case of error to be on the safe side.
Also remove the definition of SYSS_RESETDONE_MASK and use the one in omap_hwmod.h.

Cc Kevin Hilman <[email protected]>
[For the arch/arm/plat-omap/i2c.c part]
Acked-by Tony Lindgren <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 ++
 drivers/i2c/busses/i2c-omap.c |   53 +++++++++++++++++++++++++++--------------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 39 insertions(+), 18 deletions(-)
arch/arm/plat-omap/i2c.c +3 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);
drivers/i2c/busses/i2c-omap.c +1 -0
index a882558..76cf066 100644
@@ -43,6 +43,7 @@
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
 #include <linux/pm_runtime.h>
+#include <plat/omap_device.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_OMAP1_REV_2		0x20

drivers/i2c/busses/i2c-omap.c enum { · line 162

Quoted 6 lines
drivers/i2c/busses/i2c-omap.c +0 -3
@@ -157,9 +158,6 @@ enum {
 #define OMAP_I2C_SYSTEST_SDA_I		(1 << 1)	/* SDA line sense in */
 #define OMAP_I2C_SYSTEST_SDA_O		(1 << 0)	/* SDA line drive out */
 
-/* OCP_SYSSTATUS bit definitions */
-#define SYSS_RESETDONE_MASK		(1 << 0)
-

Unrelated to this patch.

Quoted 73 lines
drivers/i2c/busses/i2c-omap.c +24 -7
 /* OCP_SYSCONFIG bit definitions */
 #define SYSC_CLOCKACTIVITY_MASK		(0x3 << 8)
 #define SYSC_SIDLEMODE_MASK		(0x3 << 3)

@@ -184,6 +182,7 @@ struct omap_i2c_dev {
 	u32			latency;	/* maximum mpu wkup latency */
 	void			(*set_mpu_wkup_lat)(struct device *dev,
 						    long latency);
+	int			(*get_context_loss_count)(struct device *dev);
 	u32			speed;		/* Speed of bus in kHz */
 	u32			dtrev;		/* extra revision from DT */
 	u32			flags;

@@ -206,6 +205,7 @@ struct omap_i2c_dev {
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
+	int			dev_lost_count;
 };
 
 static const u8 reg_map_ip_v1[] = {

@@ -1025,6 +1025,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->speed = pdata->clkrate;
 		dev->flags = pdata->flags;
 		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+		dev->get_context_loss_count = pdata->get_context_loss_count;
 		dev->dtrev = pdata->rev;
 	}
 

@@ -1151,12 +1152,32 @@ omap_i2c_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_RUNTIME
+static void omap_i2c_restore(struct omap_i2c_dev *dev)
+{
+	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_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 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;
 
+	if (_dev->get_context_loss_count)
+		_dev->dev_lost_count = _dev->get_context_loss_count(dev);
+
 	_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);

@@ -1179,24 +1200,20 @@ 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);
+	int loss_cnt;
 
-	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);

drivers/i2c/busses/i2c-omap.c static int omap_i2c_runtime_resume(struct device *dev) · line 1212

Quoted 10 lines
drivers/i2c/busses/i2c-omap.c +8 -2
-		omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
-		omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+	if (_dev->get_context_loss_count) {
+		loss_cnt = _dev->get_context_loss_count(dev);
+		if (loss_cnt < 0) {
+			omap_i2c_restore(_dev);
+			return 0;
+		}
+		if (_dev->dev_lost_count == loss_cnt && _dev->dev_lost_count)
+			return 0;

Again, why does it matter if _dev->dev_lost_count != 0?

IMO, this is still more confusing than it needs to be. What is wrong with

	if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE)
		return 0;

	/* read current loss_cnt */

	if (_dev->dev_lost_count != loss_cnt)
		omap_i2c_restore(_dev);

        return 0;

Kevin

Quoted 24 lines
drivers/i2c/busses/i2c-omap.c +2 -6
-	/*
-	 * 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_restore(_dev);
 
 	return 0;
 }
include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif

A message that is not in the archive (sent off-list or not yet received): CANQgH-af1VCutKqpq8jK1yTPHybgvnUNA3zdfQq4AYcWcJRtvA@mail.gmail.com

author
#12 lore raw

PATCH v8 4/18 I2C: OMAP: I2C register restore only if context is lost

Quoted 8 lines · Shubhrajyoti
Quoted 2 lines · Kevin Hilman

"

Quoted 10 lines
Quoted 8 lines

Review

Quoted 6 lines

?#define OMAP_I2C_SYSTEST_SDA_O ? ? ? ? ? ? ? (1 << 0) ? ? ? ?/* SDA line drive out */

(quoted diff) +0 -3
-/* OCP_SYSSTATUS bit definitions */
-#define SYSS_RESETDONE_MASK ? ? ? ? ?(1 << 0)
-

Unrelated to this patch.

Actually if this is not removed we get a warn as the header file gets added when I add omap_device.h and the compiler sees a redefinition. However I agree that it can be a seperate patch.

Here is the updated patch with your comments.
Thanks.

Quoted 1 line

From c5efbe2bb050c113a1cb1b959a8890578ba9b237 Mon Sep 17 00:00:00 2001

From: Shubhrajyoti D <[email protected]>
Date: Fri, 20 Apr 2012 11:15:28 +0530
Subject: [PATCH] I2C: OMAP: I2C register restore only if context is lost

Currently i2c register restore is done always. Adding conditional restore.
The i2c register restore is done only if the context is lost or in case of error to be on the safe side.

Cc Kevin Hilman <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 arch/arm/plat-omap/i2c.c      |    3 +++
 drivers/i2c/busses/i2c-omap.c |   35 ++++++++++++++++++++++++++---------
 include/linux/i2c-omap.h      |    1 +
 3 files changed, 30 insertions(+), 9 deletions(-)
arch/arm/plat-omap/i2c.c +3 -0
index db071bc..4ccab07 100644
@@ -179,6 +179,9 @@ static inline int omap2_i2c_add_bus(int bus_id)
 	 */
 	if (cpu_is_omap34xx())
 		pdata->set_mpu_wkup_lat = omap_pm_set_max_mpu_wakeup_lat_compat;
+
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+
 	pdev = omap_device_build(name, bus_id, oh, pdata,
 			sizeof(struct omap_i2c_bus_platform_data),
 			NULL, 0, 0);
drivers/i2c/busses/i2c-omap.c +26 -9
index f5094b1..d95b01b 100644
@@ -43,6 +43,7 @@
 #include <linux/slab.h>
 #include <linux/i2c-omap.h>
 #include <linux/pm_runtime.h>
+#include <plat/omap_device.h>
 
 /* I2C controller revisions */
 #define OMAP_I2C_OMAP1_REV_2		0x20

@@ -185,6 +186,7 @@ struct omap_i2c_dev {
 	u32			latency;	/* maximum mpu wkup latency */
 	void			(*set_mpu_wkup_lat)(struct device *dev,
 						    long latency);
+	int			(*get_context_loss_count)(struct device *dev);
 	u32			speed;		/* Speed of bus in kHz */
 	u32			dtrev;		/* extra revision from DT */
 	u32			flags;

@@ -207,6 +209,7 @@ struct omap_i2c_dev {
 	u16			syscstate;
 	u16			westate;
 	u16			errata;
+	int			dev_lost_count;
 };
 
 static const u8 reg_map_ip_v1[] = {

@@ -989,6 +992,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->speed = pdata->clkrate;
 		dev->flags = pdata->flags;
 		dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
+		dev->get_context_loss_count = pdata->get_context_loss_count;
 		dev->dtrev = pdata->rev;
 	}
 

@@ -1133,12 +1137,26 @@ omap_i2c_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM_RUNTIME
+static void omap_i2c_restore(struct omap_i2c_dev *dev)
+{
+	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_WE_REG, dev->westate);
+	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
+
+}
 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;
 
+	if (_dev->get_context_loss_count)
+		_dev->dev_lost_count = _dev->get_context_loss_count(dev);
+
 	_dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
 
 	omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);

@@ -1159,16 +1177,15 @@ 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);
+	int loss_cnt;
+
+	if (!(_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE))
+		return 0;
 
-	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);
+	if (_dev->get_context_loss_count) {
+		loss_cnt = _dev->get_context_loss_count(dev);
+		if (_dev->dev_lost_count != loss_cnt)
+			omap_i2c_restore(_dev);
 	}
 
 	/*
include/linux/i2c-omap.h +1 -0
index 92a0dc7..c76cbc0 100644
@@ -35,6 +35,7 @@ struct omap_i2c_bus_platform_data {
 	u32		rev;
 	u32		flags;
 	void		(*set_mpu_wkup_lat)(struct device *dev, long set);
+	int		(*get_context_loss_count)(struct device *dev);
 };
 
 #endif
Signature · 1 line
1.7.5.4
author
#13 lore raw

PATCH v8 5/18 I2C: OMAP: Fix the interrupt clearing in OMAP4

In reply to 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 <[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.

Cc Vikram Pandita <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)
drivers/i2c/busses/i2c-omap.c +2 -4
index 45389db..2769f67 100644
@@ -1179,10 +1179,8 @@ static int omap_i2c_runtime_suspend(struct device *dev)
 		_dev->dev_lost_count = _dev->get_context_loss_count(dev);
 
 	_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 */
Signature · 1 line
1.7.4.1
author
#14 lore raw

PATCH v8 6/18 I2C: OMAP: Fix the mismatch of pm_runtime enable and disable

In reply to 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 <[email protected]>
Cc Rajendra Nayak <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
drivers/i2c/busses/i2c-omap.c +2 -0
index 2769f67..3670088 100644
@@ -1124,6 +1124,7 @@ 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);

@@ -1144,6 +1145,7 @@ 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);
Signature · 1 line
1.7.4.1
author
#15 lore raw

PATCH v8 7/18 I2C: OMAP: Optimise the remove code

In reply to Shubhrajyoti D

The omap_i2c_remove function may not be needed after device exit so the memory could be freed.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
drivers/i2c/busses/i2c-omap.c +2 -3
index 3670088..2096726 100644
@@ -1134,8 +1134,7 @@ err_release_region:
 	return r;
 }
 
-static int
-omap_i2c_remove(struct platform_device *pdev)
+static int __devexit omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
 	struct resource		*mem;

@@ -1228,7 +1227,7 @@ static struct dev_pm_ops omap_i2c_pm_ops = {
 
 static struct platform_driver omap_i2c_driver = {
 	.probe		= omap_i2c_probe,
-	.remove		= omap_i2c_remove,
+	.remove		= __devexit_p(omap_i2c_remove),
 	.driver		= {
 		.name	= "omap_i2c",
 		.owner	= THIS_MODULE,
Signature · 1 line
1.7.4.1
author
#16 lore raw

PATCH v8 8/18 I2C: OMAP: Fix the error handling

In reply to 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.
Attempting to fix the same by moving the pm_rintime_put after the error check.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
drivers/i2c/busses/i2c-omap.c +2 -2
index 2096726..a461097 100644
@@ -1095,8 +1095,6 @@ 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;

@@ -1116,6 +1114,8 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	of_i2c_register_devices(adap);
 
+	pm_runtime_put(dev->dev);
+
 	return 0;
 
 err_free_irq:
Signature · 1 line
1.7.4.1
author
#17 lore raw

PATCH v8 9/18 I2C: OMAP: Correct I2C revision for OMAP3

In reply to Shubhrajyoti D

From: Jon Hunter <[email protected]>

The OMAP3530 is based upon the same silicon as the OMAP3430 and so the I2C revision is the same for 3430 and 3530. However, the OMAP3630 device has the same I2C revision as OMAP4. Correct the revision definition to reflect this.

This patch is based on work done by Jon Hunter <[email protected]> Changes from his patch
- Update OMAP_I2C_REV_ON_3430 also to reflect that it is same as 3530

Signed-off-by Jon Hunter <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)
drivers/i2c/busses/i2c-omap.c +5 -5
index a461097..959e97c 100644
@@ -50,8 +50,8 @@
 
 /* I2C controller revisions present on specific hardware */
 #define OMAP_I2C_REV_ON_2430		0x36
-#define OMAP_I2C_REV_ON_3430		0x3C
-#define OMAP_I2C_REV_ON_3530_4430	0x40
+#define OMAP_I2C_REV_ON_3430_3530	0x3C
+#define OMAP_I2C_REV_ON_3630_4430	0x40
 
 /* timeout waiting for the controller to respond */
 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))

@@ -298,7 +298,7 @@ static int omap_i2c_reset(struct omap_i2c_dev *dev)
 			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
 					   SYSC_AUTOIDLE_MASK);
 
-		} else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
+		} else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
 			dev->syscstate = SYSC_AUTOIDLE_MASK;
 			dev->syscstate |= SYSC_ENAWAKEUP_MASK;
 			dev->syscstate |= (SYSC_IDLEMODE_SMART <<

@@ -1051,7 +1051,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 
-	if (dev->rev <= OMAP_I2C_REV_ON_3430)
+	if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
 		dev->errata |= I2C_OMAP3_1P153;
 
 	if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {

@@ -1069,7 +1069,7 @@ omap_i2c_probe(struct platform_device *pdev)
 
 		dev->fifo_size = (dev->fifo_size / 2);
 
-		if (dev->rev >= OMAP_I2C_REV_ON_3530_4430)
+		if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
 			dev->b_hw = 0; /* Disable hardware fixes */
 		else
 			dev->b_hw = 1; /* Enable hardware fixes */
Signature · 1 line
1.7.4.1
author
#18 lore raw

PATCH v8 10/18 I2C: OMAP: Don't check if wait_for_completion_timeout() returns less than zero

In reply to 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 <[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

Cc Jon Hunter <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)
drivers/i2c/busses/i2c-omap.c +4 -6
index 959e97c..121c52e 100644
@@ -502,7 +502,7 @@ 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",

@@ -570,12 +570,10 @@ 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_reset(dev);
 		omap_i2c_init(dev);
Signature · 1 line
1.7.4.1
author
#19 lore raw

PATCH v8 11/18 I2C: OMAP: use devm_* functions

In reply to Shubhrajyoti D

The various devm_ functions allocate memory that is released when a driver detaches. This patch uses devm_kzalloc, devm_request_mem_region and devm_ioremap for data that is allocated in the probe function of a platform device and is only freed in the remove function.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   34 +++++++++-------------------------
 1 files changed, 9 insertions(+), 25 deletions(-)
drivers/i2c/busses/i2c-omap.c +9 -25
index 121c52e..76b7b62 100644
@@ -976,7 +976,7 @@ omap_i2c_probe(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev;
 	struct i2c_adapter	*adap;
-	struct resource		*mem, *irq, *ioarea;
+	struct resource		*mem, *irq;
 	struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
 	struct device_node	*node = pdev->dev.of_node;
 	const struct of_device_id *match;

@@ -995,17 +995,16 @@ omap_i2c_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	ioarea = request_mem_region(mem->start, resource_size(mem),
-			pdev->name);
-	if (!ioarea) {
-		dev_err(&pdev->dev, "I2C region already claimed\n");
-		return -EBUSY;
+	dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
+	if (!dev) {
+		dev_err(&pdev->dev, "Menory allocation failed\n");
+		return -ENOMEM;
 	}
 
-	dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
-	if (!dev) {
-		r = -ENOMEM;
-		goto err_release_region;
+	dev->base = devm_request_and_ioremap(&pdev->dev, mem);
+	if (!dev->base) {
+		dev_err(&pdev->dev, "I2C region already claimed\n");
+		return -ENOMEM;
 	}
 
 	match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);

@@ -1029,11 +1028,6 @@ omap_i2c_probe(struct platform_device *pdev)
 
 	dev->dev = &pdev->dev;
 	dev->irq = irq->start;
-	dev->base = ioremap(mem->start, resource_size(mem));
-	if (!dev->base) {
-		r = -ENOMEM;
-		goto err_free_mem;
-	}
 
 	platform_set_drvdata(pdev, dev);
 

@@ -1121,13 +1115,8 @@ err_free_irq:
 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);
-err_release_region:
-	release_mem_region(mem->start, resource_size(mem));
 
 	return r;
 }

@@ -1135,7 +1124,6 @@ err_release_region:
 static int __devexit omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
-	struct resource		*mem;
 
 	platform_set_drvdata(pdev, NULL);
 

@@ -1143,10 +1131,6 @@ static int __devexit omap_i2c_remove(struct platform_device *pdev)
 	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);
-	release_mem_region(mem->start, resource_size(mem));
 	return 0;
 }
Signature · 1 line
1.7.4.1
author
#20 lore raw

PATCH v8 12/18 I2C: OMAP: Fix the crash in i2c remove

In reply to 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 <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
drivers/i2c/busses/i2c-omap.c +2 -0
index 76b7b62..edc4826 100644
@@ -1129,7 +1129,9 @@ static int __devexit 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);
 	return 0;
 }
Signature · 1 line
1.7.4.1
author
#21 lore raw

PATCH v8 13/18 I2C: OMAP: Handle error check for pm runtime

In reply to 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 <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   19 ++++++++++++++++---
 1 files changed, 16 insertions(+), 3 deletions(-)
drivers/i2c/busses/i2c-omap.c +16 -3
index edc4826..95fb9f9 100644
@@ -616,7 +616,11 @@ 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) {
+		dev_err(dev->dev, "pm_runtime_get_sync failed %d\n", r);
+		return r;
+	}
 
 	r = omap_i2c_wait_for_bb(dev);
 	if (r < 0)

@@ -1039,7 +1043,11 @@ 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) {
+		dev_err(dev->dev, "pm_runtime_get_sync failed:%d\n", r);
+		return r;
+	}
 
 	dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
 

@@ -1124,12 +1132,17 @@ err_unuse_clocks:
 static int __devexit omap_i2c_remove(struct platform_device *pdev)
 {
 	struct omap_i2c_dev	*dev = platform_get_drvdata(pdev);
+	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) {
+		dev_err(dev->dev, "pm_runtime_get_sync failed %d\n", ret);
+		return ret;
+	}
 	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
Signature · 1 line
1.7.4.1
author
#22 lore raw

PATCH v8 14/18 I2C: OMAP: Use SET_RUNTIME_PM_OPS

In reply to Shubhrajyoti D

Use SET_RUNTIME_PM_OPS macro to set runtime functions.

Acked-by Felipe Balbi <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)
drivers/i2c/busses/i2c-omap.c +5 -3
index 95fb9f9..4815528 100644
@@ -1149,6 +1149,7 @@ static int __devexit omap_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
 #ifdef CONFIG_PM_RUNTIME
 static void omap_i2c_restore(struct omap_i2c_dev *dev)
 {

@@ -1212,15 +1213,16 @@ static int omap_i2c_runtime_resume(struct device *dev)
 
 	return 0;
 }
+#endif /* CONFIG_PM_RUNTIME */
 
 static struct dev_pm_ops omap_i2c_pm_ops = {
-	.runtime_suspend = omap_i2c_runtime_suspend,
-	.runtime_resume = omap_i2c_runtime_resume,
+	SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
+			   omap_i2c_runtime_resume, NULL)
 };
 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
 #else
 #define OMAP_I2C_PM_OPS NULL
-#endif
+#endif /* CONFIG_PM */
 
 static struct platform_driver omap_i2c_driver = {
 	.probe		= omap_i2c_probe,
Signature · 1 line
1.7.4.1
author
#23 lore raw

PATCH v8 15/18 I2C: OMAP: make the read ready processing a separate function

In reply to Shubhrajyoti D

No functional change. Makes the read ready processing a separate function. This is to avoid extremely long level of indentation.

Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   86 +++++++++++++++++++++-------------------
 1 files changed, 45 insertions(+), 41 deletions(-)
drivers/i2c/busses/i2c-omap.c +45 -41
index 4815528..fbf65e2 100644
@@ -786,6 +786,49 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 	return 0;
 }
 
+static int process_read_rdy(struct omap_i2c_dev *dev)
+{
+	u8 num_bytes = 1;
+	u16 stat, w;
+
+	if (dev->errata & I2C_OMAP_ERRATA_I207)
+		i2c_omap_errata_i207(dev, stat);
+
+	if (dev->fifo_size) {
+		if (stat & OMAP_I2C_STAT_RRDY)
+			num_bytes = dev->fifo_size;
+		else    /* read RXSTAT on RDR interrupt */
+			num_bytes = (omap_i2c_read_reg(dev,
+					OMAP_I2C_BUFSTAT_REG) >> 8) & 0x3F;
+	}
+	while (num_bytes) {
+		num_bytes--;
+		w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+		if (dev->buf_len) {
+			*dev->buf++ = w;
+			dev->buf_len--;
+			/*
+			 * Data reg in 2430, omap3 and omap4 is 8 bit wide
+			 */
+			if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
+				if (dev->buf_len) {
+					*dev->buf++ = w >> 8;
+					dev->buf_len--;
+				}
+			}
+		} else {
+			if (stat & OMAP_I2C_STAT_RRDY)
+				dev_err(dev->dev,
+					"RRDY IRQ while no data requested\n");
+			if (stat & OMAP_I2C_STAT_RDR)
+				dev_err(dev->dev,
+					"RDR IRQ while no data requested\n");
+			return -EIO;
+		}
+	}
+	return 0;
+}
+
 static irqreturn_t
 omap_i2c_isr(int this_irq, void *dev_id)
 {

@@ -836,48 +879,9 @@ complete:
 			return IRQ_HANDLED;
 		}
 		if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
-			u8 num_bytes = 1;
-
-			if (dev->errata & I2C_OMAP_ERRATA_I207)
-				i2c_omap_errata_i207(dev, stat);
+			if (process_read_rdy(dev) == -EIO)
+				break;
 
-			if (dev->fifo_size) {
-				if (stat & OMAP_I2C_STAT_RRDY)
-					num_bytes = dev->fifo_size;
-				else    /* read RXSTAT on RDR interrupt */
-					num_bytes = (omap_i2c_read_reg(dev,
-							OMAP_I2C_BUFSTAT_REG)
-							>> 8) & 0x3F;
-			}
-			while (num_bytes) {
-				num_bytes--;
-				w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
-				if (dev->buf_len) {
-					*dev->buf++ = w;
-					dev->buf_len--;
-					/*
-					 * Data reg in 2430, omap3 and
-					 * omap4 is 8 bit wide
-					 */
-					if (dev->flags &
-						 OMAP_I2C_FLAG_16BIT_DATA_REG) {
-						if (dev->buf_len) {
-							*dev->buf++ = w >> 8;
-							dev->buf_len--;
-						}
-					}
-				} else {
-					if (stat & OMAP_I2C_STAT_RRDY)
-						dev_err(dev->dev,
-							"RRDY IRQ while no data"
-								" requested\n");
-					if (stat & OMAP_I2C_STAT_RDR)
-						dev_err(dev->dev,
-							"RDR IRQ while no data"
-								" requested\n");
-					break;
-				}
-			}
 			omap_i2c_ack_stat(dev,
 				stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
 			continue;
Signature · 1 line
1.7.4.1
author
#24 lore raw

PATCH v8 16/18 I2C: OMAP: fix missing handling of errata I2C_OMAP3_1P153

In reply to Shubhrajyoti D

From: Tasslehoff Kjappfot <[email protected]>

i2c_probe set the dev->errata flag, but omap_i2c_init cleared the flag again. Move the errata handling to i2c_probe.

Signed-off-by Tasslehoff Kjappfot <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)
drivers/i2c/busses/i2c-omap.c +5 -5
index fbf65e2..2976a7e 100644
@@ -431,11 +431,6 @@ 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 |

@@ -1055,6 +1050,11 @@ 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_3530)
 		dev->errata |= I2C_OMAP3_1P153;
Signature · 1 line
1.7.4.1
author
#25 lore raw

PATCH v8 17/18 I2C: OMAP: Do not set the XUDF if the underflow is not reached

In reply to Shubhrajyoti D

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

Cc Alexander Shishkin <[email protected]>
Acked-by Moiz Sonasath <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
drivers/i2c/busses/i2c-omap.c +1 -1
index 2976a7e..9239e9c 100644
@@ -765,7 +765,6 @@ 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;
 		}
 

@@ -778,6 +777,7 @@ static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
 		return 0;
 	}
 
+	*err |= OMAP_I2C_STAT_XUDF;
 	return 0;
 }
Signature · 1 line
1.7.4.1
author
#26 lore raw

PATCH v8 18/18 I2C: OMAP: Rename the 1p153 to the erratum id i462

In reply to 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 <[email protected]>
Signed-off-by Shubhrajyoti D <[email protected]>
---
 drivers/i2c/busses/i2c-omap.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)
drivers/i2c/busses/i2c-omap.c +6 -6
index 9239e9c..c592497 100644
@@ -170,7 +170,7 @@ 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;

@@ -753,11 +753,11 @@ 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;
 

@@ -920,8 +920,8 @@ 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);

@@ -1056,7 +1056,7 @@ omap_i2c_probe(struct platform_device *pdev)
 		dev->errata |= I2C_OMAP_ERRATA_I207;
 
 	if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
-		dev->errata |= I2C_OMAP3_1P153;
+		dev->errata |= I2C_OMAP_ERRATA_I462;
 
 	if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
 		u16 s;
Signature · 1 line
1.7.4.1