Add devicetree support for ad5933

Set a single voltage regulator for all voltage references. Remove voltage reference value from default platafrom data struct.

Signed-off-by Marcelo Schmitt <[email protected]>

Signed-off-by Gabriel Capella <[email protected]>

Co-Developed-by Gabriel Capella <[email protected]>

---
 drivers/staging/iio/impedance-analyzer/ad5933.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

drivers/staging/iio/impedance-analyzer/ad5933.c +6 -8

index 9e52384f5370..730bc397a26b 100644
@@ -91,7 +91,6 @@
 
 struct ad5933_platform_data {
 	unsigned long			ext_clk_hz;
-	unsigned short			vref_mv;
 };
 
 struct ad5933_state {

@@ -113,7 +112,6 @@ struct ad5933_state {
 };
 
 static struct ad5933_platform_data ad5933_default_pdata  = {
-	.vref_mv = 3300,
 };
 
 #define AD5933_CHANNEL(_type, _extend_name, _info_mask_separate, _address, \

@@ -691,7 +689,7 @@ static void ad5933_work(struct work_struct *work)
 static int ad5933_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
-	int ret, voltage_uv = 0;
+	int ret;
 	struct ad5933_platform_data *pdata = dev_get_platdata(&client->dev);
 	struct ad5933_state *st;
 	struct iio_dev *indio_dev;

@@ -718,12 +716,12 @@ static int ad5933_probe(struct i2c_client *client,
 		dev_err(&client->dev, "Failed to enable specified VDD supply\n");
 		return ret;
 	}
-	voltage_uv = regulator_get_voltage(st->reg);
+	ret = regulator_get_voltage(st->reg);
+
+	if (ret < 0)
+		goto error_disable_reg;
 
-	if (voltage_uv)
-		st->vref_mv = voltage_uv / 1000;
-	else
-		st->vref_mv = pdata->vref_mv;
+	st->vref_mv = ret / 1000;
 
 	if (pdata->ext_clk_hz) {
 		st->mclk_hz = pdata->ext_clk_hz;

Add the option to specify the external clock (MCLK) using the clock framework.
Also remove the old platform data structure.

Signed-off-by Marcelo Schmitt <[email protected]>

Signed-off-by Gabriel Capella <[email protected]>

Co-Developed-by Gabriel Capella <[email protected]>

---
 .../staging/iio/impedance-analyzer/ad5933.c   | 43 ++++++++++---------
 1 file changed, 22 insertions(+), 21 deletions(-)

drivers/staging/iio/impedance-analyzer/ad5933.c +22 -21

index 730bc397a26b..3134295f014f 100644
@@ -16,6 +16,7 @@
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/module.h>
+#include <linux/clk.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>

@@ -82,20 +83,10 @@
 #define AD5933_POLL_TIME_ms		10
 #define AD5933_INIT_EXCITATION_TIME_ms	100
 
-/**
- * struct ad5933_platform_data - platform specific data
- * @ext_clk_hz:		the external clock frequency in Hz, if not set
- *			the driver uses the internal clock (16.776 MHz)
- * @vref_mv:		the external reference voltage in millivolt
- */
-
-struct ad5933_platform_data {
-	unsigned long			ext_clk_hz;
-};
-
 struct ad5933_state {
 	struct i2c_client		*client;
 	struct regulator		*reg;
+	struct clk			*mclk;
 	struct delayed_work		work;
 	struct mutex			lock; /* Protect sensor state */
 	unsigned long			mclk_hz;

@@ -111,9 +102,6 @@ struct ad5933_state {
 	unsigned int			poll_time_jiffies;
 };
 
-static struct ad5933_platform_data ad5933_default_pdata  = {
-};
-
 #define AD5933_CHANNEL(_type, _extend_name, _info_mask_separate, _address, \
 		_scan_index, _realbits) { \
 	.type = (_type), \

@@ -690,9 +678,9 @@ static int ad5933_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
 	int ret;
-	struct ad5933_platform_data *pdata = dev_get_platdata(&client->dev);
 	struct ad5933_state *st;
 	struct iio_dev *indio_dev;
+	unsigned long ext_clk_hz = 0;
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
 	if (!indio_dev)

@@ -704,9 +692,6 @@ static int ad5933_probe(struct i2c_client *client,
 
 	mutex_init(&st->lock);
 
-	if (!pdata)
-		pdata = &ad5933_default_pdata;
-
 	st->reg = devm_regulator_get(&client->dev, "vdd");
 	if (IS_ERR(st->reg))
 		return PTR_ERR(st->reg);

@@ -723,8 +708,21 @@ static int ad5933_probe(struct i2c_client *client,
 
 	st->vref_mv = ret / 1000;
 
-	if (pdata->ext_clk_hz) {
-		st->mclk_hz = pdata->ext_clk_hz;
+	st->mclk = devm_clk_get(&client->dev, "mclk");
+	if (IS_ERR(st->mclk) && PTR_ERR(st->mclk) != -ENOENT) {
+		ret = PTR_ERR(st->mclk);
+		goto error_disable_reg;
+	}
+
+	if (!IS_ERR(st->mclk)) {
+		ret = clk_prepare_enable(st->mclk);
+		if (ret < 0)
+			goto error_disable_reg;
+		ext_clk_hz = clk_get_rate(st->mclk);
+	}
+
+	if (ext_clk_hz) {
+		st->mclk_hz = ext_clk_hz;
 		st->ctrl_lb = AD5933_CTRL_EXT_SYSCLK;
 	} else {
 		st->mclk_hz = AD5933_INT_OSC_FREQ_Hz;

@@ -744,7 +742,7 @@ static int ad5933_probe(struct i2c_client *client,
 
 	ret = ad5933_register_ring_funcs_and_init(indio_dev);
 	if (ret)
-		goto error_disable_reg;
+		goto error_disable_mclk;
 
 	ret = ad5933_setup(st);
 	if (ret)

@@ -758,6 +756,8 @@ static int ad5933_probe(struct i2c_client *client,
 
 error_unreg_ring:
 	iio_kfifo_free(indio_dev->buffer);
+error_disable_mclk:
+	clk_disable_unprepare(st->mclk);
 error_disable_reg:
 	regulator_disable(st->reg);
 

@@ -772,6 +772,7 @@ static int ad5933_remove(struct i2c_client *client)
 	iio_device_unregister(indio_dev);
 	iio_kfifo_free(indio_dev->buffer);
 	regulator_disable(st->reg);
+	clk_disable_unprepare(st->mclk);
 
 	return 0;
 }

Add a devicetree documentation for the ad5933 and ad5934 impedance converter, network analyzer.

Signed-off-by Marcelo Schmitt <[email protected]>

Signed-off-by Gabriel Capella <[email protected]>

Co-Developed-by Gabriel Capella <[email protected]>

---
 .../iio/impedance-analyzer/ad5933.txt         | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt

Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt new file +26 -0

new file mode 100644
index 000000000000..5ff38728ff91
@@ -0,0 +1,26 @@
+Analog Devices AD5933/AD5934 Impedance Converter, Network Analyzer
+
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5933.pdf
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5934.pdf
+
+Required properties:
+ - compatible : should be one of
+		"adi,ad5933"
+		"adi,ad5934"
+ - reg : the I2C address.
+ - vdd-supply : The regulator supply for DVDD, AVDD1 and AVDD2 when they
+   are connected together.
+
+Optional properties:
+- clocks : external clock reference.
+- clock-names : must be "mclk" if clocks is set.
+
+Example for a I2C device node:
+
+	impedance-analyzer@0d {
+		compatible = "adi,adxl345";
+		reg = <0x0d>;
+		vdd-supply = <&vdd_supply>;
+		clocks = <&ref_clk>;
+		clock-names = "mclk";
+	};

Quoted 6 lines · On Sat, 8 Dec 2018 16:19:59 -0200 Marcelo Schmitt <[email protected]>…

Add a devicetree documentation for the ad5933 and ad5934 impedance converter, network analyzer.

Signed-off-by Marcelo Schmitt <[email protected]>

Signed-off-by Gabriel Capella <[email protected]>

Co-Developed-by Gabriel Capella <[email protected]>

Device tree binding patches need to also go to the DT maintainers and list for review.

This looks fine to me but they are the specialists in these!

+cc Rob, Mark and DT list.

Jonathan

Quoted 37 lines

---
 .../iio/impedance-analyzer/ad5933.txt         | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt

Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt new file +26 -0

new file mode 100644
index 000000000000..5ff38728ff91
@@ -0,0 +1,26 @@
+Analog Devices AD5933/AD5934 Impedance Converter, Network Analyzer
+
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5933.pdf
+https://www.analog.com/media/en/technical-documentation/data-sheets/AD5934.pdf
+
+Required properties:
+ - compatible : should be one of
+		"adi,ad5933"
+		"adi,ad5934"
+ - reg : the I2C address.
+ - vdd-supply : The regulator supply for DVDD, AVDD1 and AVDD2 when they
+   are connected together.
+
+Optional properties:
+- clocks : external clock reference.
+- clock-names : must be "mclk" if clocks is set.
+
+Example for a I2C device node:
+
+	impedance-analyzer@0d {
+		compatible = "adi,adxl345";
+		reg = <0x0d>;
+		vdd-supply = <&vdd_supply>;
+		clocks = <&ref_clk>;
+		clock-names = "mclk";
+	};  

This series of patches change voltage regulator error handling for the ad5933.
It also add an option to specify external clock reference using a clock framework and remove the old platform data structure. Finally it adds binding documentation for devicetree.

Marcelo Schmitt (3):
staging: iio: ad5933: change regulator binging for vref
staging: iio: ad5933: use clock framework for clock reference
staging: iio: ad5933: add binding doc for ad5933

 .../iio/impedance-analyzer/ad5933.txt         | 26 +++++++++
 .../staging/iio/impedance-analyzer/ad5933.c   | 57 +++++++++----------
 2 files changed, 54 insertions(+), 29 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/iio/impedance-analyzer/ad5933.txt

--
2.17.1

Parts of this work came from contributions of Alexandru Ardelean and Dragos Bogdan, I and Gabriel would like to thank for the insights provided by their previous patches. Maybe it would be the case to add them as co-authors of this patch set.

Quoted 4 lines · Marcelo Schmitt

Parts of this work came from contributions of Alexandru Ardelean and Dragos Bogdan, I and Gabriel would like to thank for the insights provided by their previous patches. Maybe it would be the case to add them as co-authors of this patch set.

That's what the Co-developed-by: tag is for, please use it :)

Quoted 6 lines · On Sat, 8 Dec 2018 22:10:43 +0100 Greg KH <[email protected]> wrote:

Quoted 4 lines · Marcelo Schmitt

Parts of this work came from contributions of Alexandru Ardelean and Dragos Bogdan, I and Gabriel would like to thank for the insights provided by their previous patches. Maybe it would be the case to add them as co-authors of this patch set.

Quoted 2 lines

That's what the Co-developed-by: tag is for, please use it :)

Alexandru, Dragos. No idea how involved you were in the actual patch...

Work amongst amongst the 4 of you what you would like to do and let us know!

Patches look fine, though we need to let the DT maintainers have a few days at least to get around to looking if they want to (they don't always on simple bindings like these).

Jonathan