[PATCH 0/3] rtc: s35390a: uie_unsupported and minor fixes

[PATCH 0/3] rtc: s35390a: uie_unsupported and minor fixes

[Richard Leitner]

As the s35390a does only support per-minute based alarms we have to
set the uie_unsupported flag. Otherwise it delays for 10sec and 
fails afterwards with modern hwclock versions.

Furthermore some other minor changes are made.

All patches were tested on an i.MX6 platform.

Richard Leitner (3):
  rtc: s35390a: clarify INT2 pin output modes
  rtc: s35390a: set uie_unsupported
  rtc: s35390a: introduce struct device in probe

 drivers/rtc/rtc-s35390a.c | 43 +++++++++++++++++++++------------------
 1 file changed, 23 insertions(+), 20 deletions(-)

-- 
2.20.1

[PATCH 1/3] rtc: s35390a: clarify INT2 pin output modes

[Richard Leitner]

Fix the INT2 mode mask to not include the "TEST" flag. Furthermore
remove the not needed reversion of bits when parsing the INT2 modes.
Instead reverse the INT2_MODE defines.

Additionally mention the flag names from the datasheet for the different
modes in the comments.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
---
 drivers/rtc/rtc-s35390a.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index 3c64dbb08109..6fb6d835b178 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -45,12 +45,13 @@
 /* flag for STATUS2 */
 #define S35390A_FLAG_TEST	0x01
 
-#define S35390A_INT2_MODE_MASK		0xF0
-
+/* INT2 pin output mode */
+#define S35390A_INT2_MODE_MASK		0x0E
 #define S35390A_INT2_MODE_NOINTR	0x00
-#define S35390A_INT2_MODE_FREQ		0x10
-#define S35390A_INT2_MODE_ALARM		0x40
-#define S35390A_INT2_MODE_PMIN_EDG	0x20
+#define S35390A_INT2_MODE_ALARM		0x02 /* INT2AE */
+#define S35390A_INT2_MODE_PMIN_EDG	0x04 /* INT2ME */
+#define S35390A_INT2_MODE_FREQ		0x08 /* INT2FE */
+#define S35390A_INT2_MODE_PMIN		0x0C /* INT2ME | INT2FE */
 
 static const struct i2c_device_id s35390a_id[] = {
 	{ "s35390a", 0 },
@@ -303,9 +304,6 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	else
 		sts = S35390A_INT2_MODE_NOINTR;
 
-	/* This chip expects the bits of each byte to be in reverse order */
-	sts = bitrev8(sts);
-
 	/* set interupt mode*/
 	err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
 	if (err < 0)
@@ -343,7 +341,7 @@ static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
 	if (err < 0)
 		return err;
 
-	if ((bitrev8(sts) & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
+	if ((sts & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
 		/*
 		 * When the alarm isn't enabled, the register to configure
 		 * the alarm time isn't accessible.
-- 
2.20.1

[PATCH 2/3] rtc: s35390a: set uie_unsupported

[Richard Leitner]

Alarms are only supported on a per minute basis. This is why
uie_unsupported is set. Furthermore issue a warning when a second based
alarm is requested.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
---
 drivers/rtc/rtc-s35390a.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index 6fb6d835b178..462407570750 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -289,6 +289,9 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
 		alm->time.tm_min, alm->time.tm_hour, alm->time.tm_mday,
 		alm->time.tm_mon, alm->time.tm_year, alm->time.tm_wday);
 
+	if (alm->time.tm_sec != 0)
+		dev_warn(&client->dev, "Alarms are only supported on a per minute basis!\n");
+
 	/* disable interrupt (which deasserts the irq line) */
 	err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
 	if (err < 0)
@@ -500,6 +503,9 @@ static int s35390a_probe(struct i2c_client *client,
 		goto exit_dummy;
 	}
 
+	/* supports per-minute alarms only, therefore set uie_unsupported */
+	s35390a->rtc->uie_unsupported = 1;
+
 	if (status1 & S35390A_FLAG_INT2)
 		rtc_update_irq(s35390a->rtc, 1, RTC_AF);
 
-- 
2.20.1

[PATCH 3/3] rtc: s35390a: introduce struct device in probe

[Richard Leitner]

To simplify access and shorten code introduce a struct device pointer in
the s35390a probe function.

Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
---
 drivers/rtc/rtc-s35390a.c | 21 ++++++++++-----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
index 462407570750..5cc2d194645b 100644
--- a/drivers/rtc/rtc-s35390a.c
+++ b/drivers/rtc/rtc-s35390a.c
@@ -436,14 +436,14 @@ static int s35390a_probe(struct i2c_client *client,
 	unsigned int i;
 	struct s35390a *s35390a;
 	char buf, status1;
+	struct device *dev = &client->dev;
 
 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 		err = -ENODEV;
 		goto exit;
 	}
 
-	s35390a = devm_kzalloc(&client->dev, sizeof(struct s35390a),
-				GFP_KERNEL);
+	s35390a = devm_kzalloc(dev, sizeof(struct s35390a), GFP_KERNEL);
 	if (!s35390a) {
 		err = -ENOMEM;
 		goto exit;
@@ -457,8 +457,8 @@ static int s35390a_probe(struct i2c_client *client,
 		s35390a->client[i] = i2c_new_dummy(client->adapter,
 					client->addr + i);
 		if (!s35390a->client[i]) {
-			dev_err(&client->dev, "Address %02x unavailable\n",
-						client->addr + i);
+			dev_err(dev, "Address %02x unavailable\n",
+				client->addr + i);
 			err = -EBUSY;
 			goto exit_dummy;
 		}
@@ -467,7 +467,7 @@ static int s35390a_probe(struct i2c_client *client,
 	err_read = s35390a_read_status(s35390a, &status1);
 	if (err_read < 0) {
 		err = err_read;
-		dev_err(&client->dev, "error resetting chip\n");
+		dev_err(dev, "error resetting chip\n");
 		goto exit_dummy;
 	}
 
@@ -481,22 +481,21 @@ static int s35390a_probe(struct i2c_client *client,
 		buf = 0;
 		err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &buf, 1);
 		if (err < 0) {
-			dev_err(&client->dev, "error disabling alarm");
+			dev_err(dev, "error disabling alarm");
 			goto exit_dummy;
 		}
 	} else {
 		err = s35390a_disable_test_mode(s35390a);
 		if (err < 0) {
-			dev_err(&client->dev, "error disabling test mode\n");
+			dev_err(dev, "error disabling test mode\n");
 			goto exit_dummy;
 		}
 	}
 
-	device_set_wakeup_capable(&client->dev, 1);
+	device_set_wakeup_capable(dev, 1);
 
-	s35390a->rtc = devm_rtc_device_register(&client->dev,
-					s35390a_driver.driver.name,
-					&s35390a_rtc_ops, THIS_MODULE);
+	s35390a->rtc = devm_rtc_device_register(dev, s35390a_driver.driver.name,
+						&s35390a_rtc_ops, THIS_MODULE);
 
 	if (IS_ERR(s35390a->rtc)) {
 		err = PTR_ERR(s35390a->rtc);
-- 
2.20.1

Re: [PATCH 1/3] rtc: s35390a: clarify INT2 pin output modes

[Alexandre Belloni]

Hello,

This seems good to me but...

On 21/05/2019 16:20:22+0200, Richard Leitner wrote:
> Fix the INT2 mode mask to not include the "TEST" flag. Furthermore
> remove the not needed reversion of bits when parsing the INT2 modes.
> Instead reverse the INT2_MODE defines.
> 
> Additionally mention the flag names from the datasheet for the different
> modes in the comments.
> 
> Signed-off-by: Richard Leitner <richard.leitner@skidata.com>
> ---
>  drivers/rtc/rtc-s35390a.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-s35390a.c b/drivers/rtc/rtc-s35390a.c
> index 3c64dbb08109..6fb6d835b178 100644
> --- a/drivers/rtc/rtc-s35390a.c
> +++ b/drivers/rtc/rtc-s35390a.c
> @@ -45,12 +45,13 @@
>  /* flag for STATUS2 */
>  #define S35390A_FLAG_TEST	0x01
>  
> -#define S35390A_INT2_MODE_MASK		0xF0
> -
> +/* INT2 pin output mode */
> +#define S35390A_INT2_MODE_MASK		0x0E
>  #define S35390A_INT2_MODE_NOINTR	0x00
> -#define S35390A_INT2_MODE_FREQ		0x10
> -#define S35390A_INT2_MODE_ALARM		0x40
> -#define S35390A_INT2_MODE_PMIN_EDG	0x20
> +#define S35390A_INT2_MODE_ALARM		0x02 /* INT2AE */
> +#define S35390A_INT2_MODE_PMIN_EDG	0x04 /* INT2ME */
> +#define S35390A_INT2_MODE_FREQ		0x08 /* INT2FE */
> +#define S35390A_INT2_MODE_PMIN		0x0C /* INT2ME | INT2FE */
>  

While you are at it you may as well use BIT().

>  static const struct i2c_device_id s35390a_id[] = {
>  	{ "s35390a", 0 },
> @@ -303,9 +304,6 @@ static int s35390a_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
>  	else
>  		sts = S35390A_INT2_MODE_NOINTR;
>  
> -	/* This chip expects the bits of each byte to be in reverse order */
> -	sts = bitrev8(sts);
> -
>  	/* set interupt mode*/
>  	err = s35390a_set_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
>  	if (err < 0)
> @@ -343,7 +341,7 @@ static int s35390a_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
>  	if (err < 0)
>  		return err;
>  
> -	if ((bitrev8(sts) & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
> +	if ((sts & S35390A_INT2_MODE_MASK) != S35390A_INT2_MODE_ALARM) {
>  		/*
>  		 * When the alarm isn't enabled, the register to configure
>  		 * the alarm time isn't accessible.
> -- 
> 2.20.1
> 

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH 1/3] rtc: s35390a: clarify INT2 pin output modes

[Richard Leitner]

On 21/05/2019 17:54, Alexandre Belloni wrote:
> Hello,
> 
> This seems good to me but...
> 
> On 21/05/2019 16:20:22+0200, Richard Leitner wrote:

>> --- a/drivers/rtc/rtc-s35390a.c
>> +++ b/drivers/rtc/rtc-s35390a.c
>> @@ -45,12 +45,13 @@
>>   /* flag for STATUS2 */
>>   #define S35390A_FLAG_TEST	0x01
>>   
>> -#define S35390A_INT2_MODE_MASK		0xF0
>> -
>> +/* INT2 pin output mode */
>> +#define S35390A_INT2_MODE_MASK		0x0E
>>   #define S35390A_INT2_MODE_NOINTR	0x00
>> -#define S35390A_INT2_MODE_FREQ		0x10
>> -#define S35390A_INT2_MODE_ALARM		0x40
>> -#define S35390A_INT2_MODE_PMIN_EDG	0x20
>> +#define S35390A_INT2_MODE_ALARM		0x02 /* INT2AE */
>> +#define S35390A_INT2_MODE_PMIN_EDG	0x04 /* INT2ME */
>> +#define S35390A_INT2_MODE_FREQ		0x08 /* INT2FE */
>> +#define S35390A_INT2_MODE_PMIN		0x0C /* INT2ME | INT2FE */
>>   
> 
> While you are at it you may as well use BIT().

Sure, will change that for v2.

regards;Richard.L