* [PATCH 1/4] i2c: add bus recovery infrastructure
2015-07-08 13:29 i2c bus recovery support Jan Luebbe
@ 2015-07-08 13:29 ` Jan Luebbe
2015-07-13 6:47 ` Sascha Hauer
2015-07-08 13:29 ` [PATCH 2/4] i2c: only use set_scl for recovery after calling prepare_recovery Jan Luebbe
` (2 subsequent siblings)
3 siblings, 1 reply; 6+ messages in thread
From: Jan Luebbe @ 2015-07-08 13:29 UTC (permalink / raw)
To: barebox
This is based on the code introduced to the kernel in
5f9296ba21b3c395e53dd84e7ff9578f97f24295.
Signed-off-by: Jan Luebbe <jluebbe@debian.org>
---
drivers/i2c/i2c.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
include/i2c/i2c.h | 42 ++++++++++++++
2 files changed, 203 insertions(+)
diff --git a/drivers/i2c/i2c.c b/drivers/i2c/i2c.c
index ebc7e23..e350ac5 100644
--- a/drivers/i2c/i2c.c
+++ b/drivers/i2c/i2c.c
@@ -23,6 +23,7 @@
#include <xfuncs.h>
#include <init.h>
#include <of.h>
+#include <gpio.h>
#include <i2c/i2c.h>
@@ -228,6 +229,133 @@ int i2c_write_reg(struct i2c_client *client, u32 addr, const u8 *buf, u16 count)
}
EXPORT_SYMBOL(i2c_write_reg);
+/* i2c bus recovery routines */
+static int get_scl_gpio_value(struct i2c_adapter *adap)
+{
+ gpio_direction_input(adap->bus_recovery_info->scl_gpio);
+ return gpio_get_value(adap->bus_recovery_info->scl_gpio);
+}
+
+static void set_scl_gpio_value(struct i2c_adapter *adap, int val)
+{
+ if (val)
+ gpio_direction_input(adap->bus_recovery_info->scl_gpio);
+ else
+ gpio_direction_output(adap->bus_recovery_info->scl_gpio, 0);
+}
+
+static int get_sda_gpio_value(struct i2c_adapter *adap)
+{
+ return gpio_get_value(adap->bus_recovery_info->sda_gpio);
+}
+
+static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+ struct device_d *dev = &adap->dev;
+ int ret = 0;
+
+ ret = gpio_request_one(bri->scl_gpio, GPIOF_IN, "i2c-scl");
+ if (ret) {
+ dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio);
+ return ret;
+ }
+
+ if (bri->get_sda) {
+ if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) {
+ /* work without SDA polling */
+ dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n",
+ bri->sda_gpio);
+ bri->get_sda = NULL;
+ }
+ }
+
+ return ret;
+}
+
+static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+
+ if (bri->get_sda)
+ gpio_free(bri->sda_gpio);
+
+ gpio_free(bri->scl_gpio);
+}
+
+/*
+ * We are generating clock pulses. ndelay() determines durating of clk pulses.
+ * We will generate clock with rate 100 KHz and so duration of both clock levels
+ * is: delay in ns = (10^6 / 100) / 2
+ */
+#define RECOVERY_NDELAY 5000
+#define RECOVERY_CLK_CNT 9
+
+static int i2c_generic_recovery(struct i2c_adapter *adap)
+{
+ struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
+ int i = 0, val = 1, ret = 0;
+
+ if (bri->prepare_recovery)
+ bri->prepare_recovery(adap);
+
+ /*
+ * By this time SCL is high, as we need to give 9 falling-rising edges
+ */
+ while (i++ < RECOVERY_CLK_CNT * 2) {
+ if (val) {
+ /* Break if SDA is high */
+ if (bri->get_sda && bri->get_sda(adap))
+ break;
+ /* SCL shouldn't be low here */
+ if (!bri->get_scl(adap)) {
+ dev_err(&adap->dev,
+ "SCL is stuck low, exit recovery\n");
+ ret = -EBUSY;
+ break;
+ }
+ }
+
+ val = !val;
+ bri->set_scl(adap, val);
+ ndelay(RECOVERY_NDELAY);
+ }
+
+ if (bri->unprepare_recovery)
+ bri->unprepare_recovery(adap);
+
+ return ret;
+}
+
+int i2c_generic_scl_recovery(struct i2c_adapter *adap)
+{
+ adap->bus_recovery_info->set_scl(adap, 1);
+ return i2c_generic_recovery(adap);
+}
+
+int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
+{
+ int ret;
+
+ ret = i2c_get_gpios_for_recovery(adap);
+ if (ret)
+ return ret;
+
+ ret = i2c_generic_recovery(adap);
+ i2c_put_gpios_for_recovery(adap);
+
+ return ret;
+}
+
+int i2c_recover_bus(struct i2c_adapter *adap)
+{
+ if (!adap->bus_recovery_info)
+ return -EOPNOTSUPP;
+
+ dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
+ return adap->bus_recovery_info->recover_bus(adap);
+}
+
/**
* i2c_new_device - instantiate one new I2C device
*
@@ -456,6 +584,39 @@ int i2c_add_numbered_adapter(struct i2c_adapter *adapter)
list_add_tail(&adapter->list, &adapter_list);
+ /* bus recovery specific initialization */
+ if (adapter->bus_recovery_info) {
+ struct i2c_bus_recovery_info *bri = adapter->bus_recovery_info;
+
+ if (!bri->recover_bus) {
+ dev_err(&adapter->dev, "No recover_bus() found, not using recovery\n");
+ adapter->bus_recovery_info = NULL;
+ goto exit_recovery;
+ }
+
+ /* Generic GPIO recovery */
+ if (bri->recover_bus == i2c_generic_gpio_recovery) {
+ if (!gpio_is_valid(bri->scl_gpio)) {
+ dev_err(&adapter->dev, "Invalid SCL gpio, not using recovery\n");
+ adapter->bus_recovery_info = NULL;
+ goto exit_recovery;
+ }
+
+ if (gpio_is_valid(bri->sda_gpio))
+ bri->get_sda = get_sda_gpio_value;
+ else
+ bri->get_sda = NULL;
+
+ bri->get_scl = get_scl_gpio_value;
+ bri->set_scl = set_scl_gpio_value;
+ } else if (!bri->set_scl || !bri->get_scl) {
+ /* Generic SCL recovery */
+ dev_err(&adapter->dev, "No {get|set}_gpio() found, not using recovery\n");
+ adapter->bus_recovery_info = NULL;
+ }
+ }
+exit_recovery:
+
/* populate children from any i2c device tables */
scan_boardinfo(adapter);
diff --git a/include/i2c/i2c.h b/include/i2c/i2c.h
index 4696f43..04de8c9 100644
--- a/include/i2c/i2c.h
+++ b/include/i2c/i2c.h
@@ -19,6 +19,8 @@
#include <driver.h>
#include <linux/types.h>
+struct i2c_adapter;
+
/*
* struct i2c_platform_data - structure of platform data for MXC I2C driver
* @param bitrate Bus speed measured in Hz
@@ -61,6 +63,44 @@ struct i2c_msg {
__u16 len; /**< Number of data bytes in @buf being read from or written to the I2C slave address. */
};
+/**
+ * struct i2c_bus_recovery_info - I2C bus recovery information
+ * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or
+ * i2c_generic_scl_recovery() or i2c_generic_gpio_recovery().
+ * @get_scl: This gets current value of SCL line. Mandatory for generic SCL
+ * recovery. Used internally for generic GPIO recovery.
+ * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used
+ * internally for generic GPIO recovery.
+ * @get_sda: This gets current value of SDA line. Optional for generic SCL
+ * recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO
+ * recovery.
+ * @prepare_recovery: This will be called before starting recovery. Platform may
+ * configure padmux here for SDA/SCL line or something else they want.
+ * @unprepare_recovery: This will be called after completing recovery. Platform
+ * may configure padmux here for SDA/SCL line or something else they want.
+ * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery.
+ * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery.
+ */
+struct i2c_bus_recovery_info {
+ int (*recover_bus)(struct i2c_adapter *);
+
+ int (*get_scl)(struct i2c_adapter *);
+ void (*set_scl)(struct i2c_adapter *, int val);
+ int (*get_sda)(struct i2c_adapter *);
+
+ void (*prepare_recovery)(struct i2c_adapter *);
+ void (*unprepare_recovery)(struct i2c_adapter *);
+
+ /* gpio recovery */
+ int scl_gpio;
+ int sda_gpio;
+};
+
+int i2c_recover_bus(struct i2c_adapter *adap);
+
+/* Generic recovery routines */
+int i2c_generic_gpio_recovery(struct i2c_adapter *adap);
+int i2c_generic_scl_recovery(struct i2c_adapter *adap);
/**
* i2c_adapter is the structure used to identify a physical i2c bus
@@ -74,6 +114,8 @@ struct i2c_adapter {
struct list_head list;
int retries;
void *algo_data;
+
+ struct i2c_bus_recovery_info *bus_recovery_info;
};
--
2.1.4
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^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 1/4] i2c: add bus recovery infrastructure
2015-07-08 13:29 ` [PATCH 1/4] i2c: add bus recovery infrastructure Jan Luebbe
@ 2015-07-13 6:47 ` Sascha Hauer
0 siblings, 0 replies; 6+ messages in thread
From: Sascha Hauer @ 2015-07-13 6:47 UTC (permalink / raw)
To: Jan Luebbe; +Cc: barebox
On Wed, Jul 08, 2015 at 03:29:15PM +0200, Jan Luebbe wrote:
> This is based on the code introduced to the kernel in
> 5f9296ba21b3c395e53dd84e7ff9578f97f24295.
>
> Signed-off-by: Jan Luebbe <jluebbe@debian.org>
> ---
> drivers/i2c/i2c.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
> include/i2c/i2c.h | 42 ++++++++++++++
> 2 files changed, 203 insertions(+)
>
> diff --git a/drivers/i2c/i2c.c b/drivers/i2c/i2c.c
> index ebc7e23..e350ac5 100644
> --- a/drivers/i2c/i2c.c
> +++ b/drivers/i2c/i2c.c
> @@ -23,6 +23,7 @@
> #include <xfuncs.h>
> #include <init.h>
> #include <of.h>
> +#include <gpio.h>
>
> #include <i2c/i2c.h>
>
> @@ -228,6 +229,133 @@ int i2c_write_reg(struct i2c_client *client, u32 addr, const u8 *buf, u16 count)
> }
> EXPORT_SYMBOL(i2c_write_reg);
>
> +/* i2c bus recovery routines */
> +static int get_scl_gpio_value(struct i2c_adapter *adap)
> +{
> + gpio_direction_input(adap->bus_recovery_info->scl_gpio);
> + return gpio_get_value(adap->bus_recovery_info->scl_gpio);
> +}
> +
> +static void set_scl_gpio_value(struct i2c_adapter *adap, int val)
> +{
> + if (val)
> + gpio_direction_input(adap->bus_recovery_info->scl_gpio);
> + else
> + gpio_direction_output(adap->bus_recovery_info->scl_gpio, 0);
> +}
> +
> +static int get_sda_gpio_value(struct i2c_adapter *adap)
> +{
> + return gpio_get_value(adap->bus_recovery_info->sda_gpio);
> +}
> +
> +static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap)
> +{
> + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
> + struct device_d *dev = &adap->dev;
> + int ret = 0;
> +
> + ret = gpio_request_one(bri->scl_gpio, GPIOF_IN, "i2c-scl");
> + if (ret) {
> + dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio);
> + return ret;
> + }
> +
> + if (bri->get_sda) {
> + if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) {
> + /* work without SDA polling */
> + dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n",
> + bri->sda_gpio);
> + bri->get_sda = NULL;
> + }
> + }
> +
> + return ret;
> +}
> +
> +static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap)
> +{
> + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
> +
> + if (bri->get_sda)
> + gpio_free(bri->sda_gpio);
> +
> + gpio_free(bri->scl_gpio);
> +}
> +
> +/*
> + * We are generating clock pulses. ndelay() determines durating of clk pulses.
> + * We will generate clock with rate 100 KHz and so duration of both clock levels
> + * is: delay in ns = (10^6 / 100) / 2
> + */
> +#define RECOVERY_NDELAY 5000
> +#define RECOVERY_CLK_CNT 9
> +
> +static int i2c_generic_recovery(struct i2c_adapter *adap)
> +{
> + struct i2c_bus_recovery_info *bri = adap->bus_recovery_info;
> + int i = 0, val = 1, ret = 0;
> +
> + if (bri->prepare_recovery)
> + bri->prepare_recovery(adap);
> +
> + /*
> + * By this time SCL is high, as we need to give 9 falling-rising edges
> + */
> + while (i++ < RECOVERY_CLK_CNT * 2) {
> + if (val) {
> + /* Break if SDA is high */
> + if (bri->get_sda && bri->get_sda(adap))
> + break;
> + /* SCL shouldn't be low here */
> + if (!bri->get_scl(adap)) {
> + dev_err(&adap->dev,
> + "SCL is stuck low, exit recovery\n");
> + ret = -EBUSY;
> + break;
> + }
> + }
> +
> + val = !val;
> + bri->set_scl(adap, val);
> + ndelay(RECOVERY_NDELAY);
> + }
> +
> + if (bri->unprepare_recovery)
> + bri->unprepare_recovery(adap);
> +
> + return ret;
> +}
> +
> +int i2c_generic_scl_recovery(struct i2c_adapter *adap)
> +{
> + adap->bus_recovery_info->set_scl(adap, 1);
> + return i2c_generic_recovery(adap);
> +}
> +
> +int i2c_generic_gpio_recovery(struct i2c_adapter *adap)
> +{
> + int ret;
> +
> + ret = i2c_get_gpios_for_recovery(adap);
> + if (ret)
> + return ret;
> +
> + ret = i2c_generic_recovery(adap);
> + i2c_put_gpios_for_recovery(adap);
> +
> + return ret;
> +}
> +
> +int i2c_recover_bus(struct i2c_adapter *adap)
> +{
> + if (!adap->bus_recovery_info)
> + return -EOPNOTSUPP;
> +
> + dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
> + return adap->bus_recovery_info->recover_bus(adap);
> +}
> +
> /**
> * i2c_new_device - instantiate one new I2C device
> *
> @@ -456,6 +584,39 @@ int i2c_add_numbered_adapter(struct i2c_adapter *adapter)
>
> list_add_tail(&adapter->list, &adapter_list);
>
> + /* bus recovery specific initialization */
> + if (adapter->bus_recovery_info) {
> + struct i2c_bus_recovery_info *bri = adapter->bus_recovery_info;
> +
> + if (!bri->recover_bus) {
> + dev_err(&adapter->dev, "No recover_bus() found, not using recovery\n");
> + adapter->bus_recovery_info = NULL;
> + goto exit_recovery;
> + }
> +
> + /* Generic GPIO recovery */
> + if (bri->recover_bus == i2c_generic_gpio_recovery) {
This comparison to i2c_generic_gpio_recovery here forces the linker to
always compile in gpio recovery support, even when it's unused in the
compiled in drivers. I think we can do better here.
Also, could you put the bus recovery support into a separate function so
that we can call it wherever we need it? We might call it from other
places later aswell.
Sascha
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^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 2/4] i2c: only use set_scl for recovery after calling prepare_recovery
2015-07-08 13:29 i2c bus recovery support Jan Luebbe
2015-07-08 13:29 ` [PATCH 1/4] i2c: add bus recovery infrastructure Jan Luebbe
@ 2015-07-08 13:29 ` Jan Luebbe
2015-07-08 13:29 ` [PATCH 3/4] i2c-omap: clear ARDY twice Jan Luebbe
2015-07-08 13:29 ` [PATCH 4/4] i2c-omap: add bus recovery support Jan Luebbe
3 siblings, 0 replies; 6+ messages in thread
From: Jan Luebbe @ 2015-07-08 13:29 UTC (permalink / raw)
To: barebox
set_scl may be ineffective before calling the driver specific
prepare_recovery callback.
Signed-off-by: Jan Luebbe <jluebbe@debian.org>
---
drivers/i2c/i2c.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/i2c.c b/drivers/i2c/i2c.c
index e350ac5..39837fe 100644
--- a/drivers/i2c/i2c.c
+++ b/drivers/i2c/i2c.c
@@ -299,6 +299,9 @@ static int i2c_generic_recovery(struct i2c_adapter *adap)
if (bri->prepare_recovery)
bri->prepare_recovery(adap);
+ bri->set_scl(adap, val);
+ ndelay(RECOVERY_NDELAY);
+
/*
* By this time SCL is high, as we need to give 9 falling-rising edges
*/
@@ -329,7 +332,6 @@ static int i2c_generic_recovery(struct i2c_adapter *adap)
int i2c_generic_scl_recovery(struct i2c_adapter *adap)
{
- adap->bus_recovery_info->set_scl(adap, 1);
return i2c_generic_recovery(adap);
}
--
2.1.4
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^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH 3/4] i2c-omap: clear ARDY twice
2015-07-08 13:29 i2c bus recovery support Jan Luebbe
2015-07-08 13:29 ` [PATCH 1/4] i2c: add bus recovery infrastructure Jan Luebbe
2015-07-08 13:29 ` [PATCH 2/4] i2c: only use set_scl for recovery after calling prepare_recovery Jan Luebbe
@ 2015-07-08 13:29 ` Jan Luebbe
2015-07-08 13:29 ` [PATCH 4/4] i2c-omap: add bus recovery support Jan Luebbe
3 siblings, 0 replies; 6+ messages in thread
From: Jan Luebbe @ 2015-07-08 13:29 UTC (permalink / raw)
To: barebox
This implements the fix from the kernel commit
4cdbf7d346e7461c3b93a26707c852e2c9db3753.
Signed-off-by: Jan Luebbe <jluebbe@debian.org>
---
drivers/i2c/busses/i2c-omap.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 330db98..58d2ec9 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -673,6 +673,10 @@ omap_i2c_isr(struct omap_i2c_struct *dev)
/*
* ProDB0017052: Clear ARDY bit twice
*/
+ if (stat & OMAP_I2C_STAT_ARDY)
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ARDY);
+
+
if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
OMAP_I2C_STAT_AL)) {
omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
--
2.1.4
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^ permalink raw reply [flat|nested] 6+ messages in thread* [PATCH 4/4] i2c-omap: add bus recovery support
2015-07-08 13:29 i2c bus recovery support Jan Luebbe
` (2 preceding siblings ...)
2015-07-08 13:29 ` [PATCH 3/4] i2c-omap: clear ARDY twice Jan Luebbe
@ 2015-07-08 13:29 ` Jan Luebbe
3 siblings, 0 replies; 6+ messages in thread
From: Jan Luebbe @ 2015-07-08 13:29 UTC (permalink / raw)
To: barebox
This is based on commit 9dcb0e7b999db6c420c70fd32497a979a044fcdf from
the kernel with some additional fixes.
Signed-off-by: Jan Luebbe <jluebbe@debian.org>
---
drivers/i2c/busses/i2c-omap.c | 91 +++++++++++++++++++++++++++++++++++++++++--
1 file changed, 88 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 58d2ec9..3abf05a 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -107,16 +107,20 @@
#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 */
+/* Functional mode */
+#define OMAP_I2C_SYSTEST_SCL_I_FUNC (1 << 8) /* SCL line input value */
+#define OMAP_I2C_SYSTEST_SCL_O_FUNC (1 << 7) /* SCL line output value */
+#define OMAP_I2C_SYSTEST_SDA_I_FUNC (1 << 6) /* SDA line input value */
+#define OMAP_I2C_SYSTEST_SDA_O_FUNC (1 << 5) /* SDA line output value */
+/* SDA/SCL IO mode */
#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)
@@ -492,7 +496,7 @@ static int omap_i2c_wait_for_bb(struct i2c_adapter *adapter)
while (omap_i2c_read_reg(i2c_omap, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
if (is_timeout(start, MSECOND)) {
dev_warn(&adapter->dev, "timeout waiting for bus ready\n");
- return -ETIMEDOUT;
+ return i2c_recover_bus(adapter);
}
}
@@ -990,6 +994,86 @@ out:
#define OMAP_I2C_SCHEME_0 0
#define OMAP_I2C_SCHEME_1 1
+static int omap_i2c_get_scl(struct i2c_adapter *adapter)
+{
+ struct omap_i2c_struct *i2c_omap = to_omap_i2c_struct(adapter);
+ u32 reg;
+
+ reg = omap_i2c_read_reg(i2c_omap, OMAP_I2C_SYSTEST_REG);
+
+ printf("%s %i\n", __func__, !!(reg & OMAP_I2C_SYSTEST_SCL_I_FUNC));
+ return reg & OMAP_I2C_SYSTEST_SCL_I_FUNC;
+}
+
+static int omap_i2c_get_sda(struct i2c_adapter *adapter)
+{
+ struct omap_i2c_struct *i2c_omap = to_omap_i2c_struct(adapter);
+ u32 reg;
+
+ reg = omap_i2c_read_reg(i2c_omap, OMAP_I2C_SYSTEST_REG);
+
+ printf("%s %i\n", __func__, !!(reg & OMAP_I2C_SYSTEST_SDA_I_FUNC));
+ return reg & OMAP_I2C_SYSTEST_SDA_I_FUNC;
+}
+
+static void omap_i2c_set_scl(struct i2c_adapter *adapter, int val)
+{
+ struct omap_i2c_struct *i2c_omap = to_omap_i2c_struct(adapter);
+ u32 reg;
+
+ printf("%s %i\n", __func__, val);
+ reg = omap_i2c_read_reg(i2c_omap, OMAP_I2C_SYSTEST_REG);
+ if (val)
+ reg |= OMAP_I2C_SYSTEST_SCL_O;
+ else
+ reg &= ~OMAP_I2C_SYSTEST_SCL_O;
+ omap_i2c_write_reg(i2c_omap, OMAP_I2C_SYSTEST_REG, reg);
+}
+
+static void omap_i2c_prepare_recovery(struct i2c_adapter *adapter)
+{
+ struct omap_i2c_struct *i2c_omap = to_omap_i2c_struct(adapter);
+ u32 reg;
+
+ printf("%s\n", __func__);
+
+ reg = omap_i2c_read_reg(i2c_omap, OMAP_I2C_SYSTEST_REG);
+ /* enable test mode */
+ reg |= OMAP_I2C_SYSTEST_ST_EN;
+ /* select SDA/SCL IO mode */
+ reg |= 3 << OMAP_I2C_SYSTEST_TMODE_SHIFT;
+ /* set SCL to high-impedance state (reset value is 0) */
+ reg |= OMAP_I2C_SYSTEST_SCL_O;
+ /* set SDA to high-impedance state (reset value is 0) */
+ reg |= OMAP_I2C_SYSTEST_SDA_O;
+ omap_i2c_write_reg(i2c_omap, OMAP_I2C_SYSTEST_REG, reg);
+}
+
+static void omap_i2c_unprepare_recovery(struct i2c_adapter *adapter)
+{
+ struct omap_i2c_struct *i2c_omap = to_omap_i2c_struct(adapter);
+ u32 reg;
+
+ printf("%s\n", __func__);
+
+ reg = omap_i2c_read_reg(i2c_omap, OMAP_I2C_SYSTEST_REG);
+ /* restore reset values */
+ reg &= ~OMAP_I2C_SYSTEST_ST_EN;
+ reg &= ~OMAP_I2C_SYSTEST_TMODE_MASK;
+ reg &= ~OMAP_I2C_SYSTEST_SCL_O;
+ reg &= ~OMAP_I2C_SYSTEST_SDA_O;
+ omap_i2c_write_reg(i2c_omap, OMAP_I2C_SYSTEST_REG, reg);
+}
+
+static struct i2c_bus_recovery_info omap_i2c_bus_recovery_info = {
+ .get_scl = omap_i2c_get_scl,
+ .get_sda = omap_i2c_get_sda,
+ .set_scl = omap_i2c_set_scl,
+ .prepare_recovery = omap_i2c_prepare_recovery,
+ .unprepare_recovery = omap_i2c_unprepare_recovery,
+ .recover_bus = i2c_generic_scl_recovery,
+};
+
static int __init
i2c_omap_probe(struct device_d *pdev)
{
@@ -1101,6 +1185,7 @@ i2c_omap_probe(struct device_d *pdev)
i2c_omap->adapter.nr = pdev->id;
i2c_omap->adapter.dev.parent = pdev;
i2c_omap->adapter.dev.device_node = pdev->device_node;
+ i2c_omap->adapter.bus_recovery_info = &omap_i2c_bus_recovery_info;
/* i2c device drivers may be active on return from add_adapter() */
r = i2c_add_numbered_adapter(&i2c_omap->adapter);
--
2.1.4
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