[PATCH v4 1/3] dt: bindings: add documentation for zx2967 family thermal sensor

[PATCH v4 1/3] dt: bindings: add documentation for zx2967 family thermal sensor

[Baoyou Xie]

This patch adds dt-binding documentation for zx2967 family thermal sensor.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Shawn Guo <shawnguo@kernel.org>
---
 .../devicetree/bindings/thermal/zx2967-thermal.txt  | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/thermal/zx2967-thermal.txt

diff --git a/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt b/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt
new file mode 100644
index 0000000..86f941c
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt
@@ -0,0 +1,21 @@
+* ZTE zx2967 family Thermal
+
+Required Properties:
+- compatible: should be one of the following.
+    * zte,zx296718-thermal
+- reg: physical base address of the controller and length of memory mapped
+    region.
+- clocks : Pairs of phandle and specifier referencing the controller's clocks.
+- clock-names: "gate" for the topcrm clock.
+	       "pclk" for the apb clock.
+- #thermal-sensor-cells: must be 0.
+
+Example:
+
+	tempsensor: tempsensor@148a000 {
+		compatible = "zte,zx296718-thermal";
+		reg = <0x0148a000 0x20>;
+		clocks = <&topcrm TEMPSENSOR_GATE>, <&audiocrm AUDIO_TS_PCLK>;
+		clock-names = "gate", "pclk";
+		#thermal-sensor-cells = <0>;
+	};
-- 
2.7.4

[PATCH v4 2/3] MAINTAINERS: add zx2967 thermal drivers to ARM ZTE architecture

[Baoyou Xie]

Add the zx2967 thermal drivers as maintained by ARM ZTE
architecture maintainers, as they're parts of the core IP.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
---
 MAINTAINERS | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 64f04df..2793808 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1981,9 +1981,11 @@ S:	Maintained
 F:	arch/arm/mach-zx/
 F:	drivers/clk/zte/
 F:	drivers/soc/zte/
+F:	drivers/thermal/zx*
 F:	Documentation/devicetree/bindings/arm/zte.txt
 F:	Documentation/devicetree/bindings/clock/zx296702-clk.txt
 F:	Documentation/devicetree/bindings/soc/zte/
+F:	Documentation/devicetree/bindings/thermal/zx*
 F:	include/dt-bindings/soc/zx*.h
 
 ARM/ZYNQ ARCHITECTURE
-- 
2.7.4

[PATCH v4 3/3] thermal: zx2967: add thermal driver for ZTE's zx2967 family

[Baoyou Xie]

This patch adds thermal driver for ZTE's zx2967 family.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
---
 drivers/thermal/Kconfig          |   6 +
 drivers/thermal/Makefile         |   1 +
 drivers/thermal/zx2967_thermal.c | 253 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 260 insertions(+)
 create mode 100644 drivers/thermal/zx2967_thermal.c

diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 18f2de6..0dd597e 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -445,3 +445,9 @@ config BCM2835_THERMAL
 	  Support for thermal sensors on Broadcom bcm2835 SoCs.
 
 endif
+
+config ZX2967_THERMAL
+	tristate "Thermal sensors on zx2967 SoC"
+	depends on ARCH_ZX
+	help
+	  Support for thermal sensors on ZTE zx2967 SoCs.
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 677c6d9..c00c05e 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_HISI_THERMAL)     += hisi_thermal.o
 obj-$(CONFIG_MTK_THERMAL)	+= mtk_thermal.o
 obj-$(CONFIG_GENERIC_ADC_THERMAL)	+= thermal-generic-adc.o
 obj-$(CONFIG_BCM2835_THERMAL)	+= bcm2835_thermal.o
+obj-$(CONFIG_ZX2967_THERMAL)	+= zx2967_thermal.o
diff --git a/drivers/thermal/zx2967_thermal.c b/drivers/thermal/zx2967_thermal.c
new file mode 100644
index 0000000..e77d07c
--- /dev/null
+++ b/drivers/thermal/zx2967_thermal.c
@@ -0,0 +1,253 @@
+/*
+ * ZTE's zx2967 family thermal sensor driver
+ *
+ * Copyright (C) 2017 ZTE Ltd.
+ *
+ * Author: Baoyou Xie <baoyou.xie@linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/thermal.h>
+
+/* Power Mode: 0->low 1->high */
+#define ZX2967_THERMAL_POWER_MODE	0
+
+/* DCF Control Register */
+#define ZX2967_THERMAL_DCF		0x4
+
+/* Selection Register */
+#define ZX2967_THERMAL_SEL		0x8
+
+/* Control Register */
+#define ZX2967_THERMAL_CTRL		0x10
+
+#define ZX2967_THERMAL_READY		0x1000
+#define ZX2967_THERMAL_TEMP_MASK	0xfff
+#define ZX2967_THERMAL_ID_MASK		0x18
+#define ZX2967_THERMAL_ID0		0x8
+#define ZX2967_THERMAL_ID1		0x10
+
+struct zx2967_thermal_sensor {
+	struct zx2967_thermal_priv *priv;
+	struct thermal_zone_device *tzd;
+	int id;
+};
+
+#define NUM_SENSORS	1
+
+struct zx2967_thermal_priv {
+	struct zx2967_thermal_sensor	sensors[NUM_SENSORS];
+	struct mutex			lock;
+	struct clk			*clk_gate;
+	struct clk			*pclk;
+	void __iomem			*regs;
+	struct device			*dev;
+};
+
+static int zx2967_thermal_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev);
+
+	if (priv && priv->pclk)
+		clk_disable_unprepare(priv->pclk);
+
+	if (priv && priv->clk_gate)
+		clk_disable_unprepare(priv->clk_gate);
+
+	return 0;
+}
+
+static int zx2967_thermal_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev);
+	int error;
+
+	error = clk_prepare_enable(priv->clk_gate);
+	if (error)
+		return error;
+
+	error = clk_prepare_enable(priv->pclk);
+	if (error) {
+		clk_disable_unprepare(priv->clk_gate);
+		return error;
+	}
+
+	return 0;
+}
+
+static int zx2967_thermal_get_temp(void *data, int *temp)
+{
+	void __iomem *regs;
+	struct zx2967_thermal_sensor *sensor = data;
+	struct zx2967_thermal_priv *priv = sensor->priv;
+	unsigned long timeout = jiffies + msecs_to_jiffies(100);
+	u32 val, sel_id;
+
+	regs = priv->regs;
+	mutex_lock(&priv->lock);
+
+	writel_relaxed(0, regs + ZX2967_THERMAL_POWER_MODE);
+	writel_relaxed(2, regs + ZX2967_THERMAL_DCF);
+
+	val = readl_relaxed(regs + ZX2967_THERMAL_SEL);
+	val &= ~ZX2967_THERMAL_ID_MASK;
+	sel_id = sensor->id ? ZX2967_THERMAL_ID0 : ZX2967_THERMAL_ID1;
+	val |= sel_id;
+	writel_relaxed(val, regs + ZX2967_THERMAL_SEL);
+
+	usleep_range(100, 300);
+	val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);
+	while (!(val & ZX2967_THERMAL_READY)) {
+		if (time_after(jiffies, timeout)) {
+			dev_err(priv->dev, "Thermal sensor %d data timeout\n",
+				sensor->id);
+			mutex_unlock(&priv->lock);
+			return -ETIMEDOUT;
+		}
+		val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);
+	}
+
+	writel_relaxed(3, regs + ZX2967_THERMAL_DCF);
+	val = readl_relaxed(regs + ZX2967_THERMAL_CTRL)
+			 & ZX2967_THERMAL_TEMP_MASK;
+	writel_relaxed(1, regs + ZX2967_THERMAL_POWER_MODE);
+
+	/*
+	 * Calculate temperature
+	 *   922	initial value of calibration cure
+	 *   1.951	slope of calibration cure
+	 */
+	*temp = DIV_ROUND_CLOSEST((val - 922) * 1000, 1951);
+
+	mutex_unlock(&priv->lock);
+
+	return 0;
+}
+
+static struct thermal_zone_of_device_ops zx2967_of_thermal_ops = {
+	.get_temp = zx2967_thermal_get_temp,
+};
+
+static int zx2967_thermal_probe(struct platform_device *pdev)
+{
+	struct zx2967_thermal_priv *priv;
+	struct resource *res;
+	int ret, i;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(priv->regs))
+		return PTR_ERR(priv->regs);
+
+	priv->clk_gate = devm_clk_get(&pdev->dev, "gate");
+	if (IS_ERR(priv->clk_gate)) {
+		ret = PTR_ERR(priv->clk_gate);
+		dev_err(&pdev->dev, "failed to get clock gate: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(priv->clk_gate);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
+			ret);
+		return ret;
+	}
+
+	priv->pclk = devm_clk_get(&pdev->dev, "pclk");
+	if (IS_ERR(priv->pclk)) {
+		ret = PTR_ERR(priv->pclk);
+		dev_err(&pdev->dev, "failed to get apb clock: %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(priv->pclk);
+	if (ret) {
+		clk_disable_unprepare(priv->clk_gate);
+		dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
+			ret);
+		return ret;
+	}
+
+	mutex_init(&priv->lock);
+	for (i = 0; i < NUM_SENSORS; i++) {
+		struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
+
+		sensor->priv = priv;
+		sensor->id = i;
+		sensor->tzd = thermal_zone_of_sensor_register(&pdev->dev,
+					i, sensor, &zx2967_of_thermal_ops);
+		if (IS_ERR(sensor->tzd)) {
+			ret = PTR_ERR(sensor->tzd);
+			dev_err(&pdev->dev, "failed to register sensor %d: %d\n",
+				i, ret);
+			goto remove_ts;
+		}
+	}
+	priv->dev = &pdev->dev;
+	platform_set_drvdata(pdev, priv);
+
+	return 0;
+
+remove_ts:
+	clk_disable_unprepare(priv->clk_gate);
+	clk_disable_unprepare(priv->pclk);
+	for (i--; i >= 0; i--)
+		thermal_zone_of_sensor_unregister(&pdev->dev,
+						  priv->sensors[i].tzd);
+
+	return ret;
+}
+
+static int zx2967_thermal_exit(struct platform_device *pdev)
+{
+	struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev);
+	int i;
+
+	for (i = 0; i < NUM_SENSORS; i++) {
+		struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
+
+		thermal_zone_of_sensor_unregister(&pdev->dev, sensor->tzd);
+	}
+	clk_disable_unprepare(priv->pclk);
+	clk_disable_unprepare(priv->clk_gate);
+
+	return 0;
+}
+
+static const struct of_device_id zx2967_thermal_id_table[] = {
+	{ .compatible = "zte,zx296718-thermal" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, zx2967_thermal_id_table);
+
+static SIMPLE_DEV_PM_OPS(zx2967_thermal_pm_ops,
+			 zx2967_thermal_suspend, zx2967_thermal_resume);
+
+static struct platform_driver zx2967_thermal_driver = {
+	.probe = zx2967_thermal_probe,
+	.remove = zx2967_thermal_exit,
+	.driver = {
+		.name = "zx2967_thermal",
+		.of_match_table = zx2967_thermal_id_table,
+		.pm = &zx2967_thermal_pm_ops,
+	},
+};
+module_platform_driver(zx2967_thermal_driver);
+
+MODULE_AUTHOR("Baoyou Xie <baoyou.xie@linaro.org>");
+MODULE_DESCRIPTION("ZTE zx2967 thermal driver");
+MODULE_LICENSE("GPL");
-- 
2.7.4

Re: [PATCH v4 3/3] thermal: zx2967: add thermal driver for ZTE's zx2967 family

[Shawn Guo]

On Fri, Jan 13, 2017 at 06:46:58PM +0800, Baoyou Xie wrote:
> This patch adds thermal driver for ZTE's zx2967 family.
> 
> Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>

Reviewed-by: Shawn Guo <shawnguo@kernel.org>

Re: [PATCH v4 3/3] thermal: zx2967: add thermal driver for ZTE's zx2967 family

[Eduardo Valentin]

Hello,

On Fri, Jan 13, 2017 at 06:46:58PM +0800, Baoyou Xie wrote:
> This patch adds thermal driver for ZTE's zx2967 family.

Please consider the comments I sent on your v3. They still apply here.

and also the following:

> 
> Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>


<cut>

> +static int zx2967_thermal_get_temp(void *data, int *temp)
> +{
> +	void __iomem *regs;
> +	struct zx2967_thermal_sensor *sensor = data;
> +	struct zx2967_thermal_priv *priv = sensor->priv;
> +	unsigned long timeout = jiffies + msecs_to_jiffies(100);
> +	u32 val, sel_id;
> +
> +	regs = priv->regs;
> +	mutex_lock(&priv->lock);
> +
> +	writel_relaxed(0, regs + ZX2967_THERMAL_POWER_MODE);
> +	writel_relaxed(2, regs + ZX2967_THERMAL_DCF);
> +
> +	val = readl_relaxed(regs + ZX2967_THERMAL_SEL);
> +	val &= ~ZX2967_THERMAL_ID_MASK;
> +	sel_id = sensor->id ? ZX2967_THERMAL_ID0 : ZX2967_THERMAL_ID1;
> +	val |= sel_id;
> +	writel_relaxed(val, regs + ZX2967_THERMAL_SEL);
> +
> +	usleep_range(100, 300);
> +	val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);
> +	while (!(val & ZX2967_THERMAL_READY)) {
> +		if (time_after(jiffies, timeout)) {
> +			dev_err(priv->dev, "Thermal sensor %d data timeout\n",
> +				sensor->id);
> +			mutex_unlock(&priv->lock);
> +			return -ETIMEDOUT;
> +		}
> +		val = readl_relaxed(regs + ZX2967_THERMAL_CTRL);

should you usleep_range() in between loops iterations?

> +	}
> +
> +	writel_relaxed(3, regs + ZX2967_THERMAL_DCF);
> +	val = readl_relaxed(regs + ZX2967_THERMAL_CTRL)
> +			 & ZX2967_THERMAL_TEMP_MASK;
> +	writel_relaxed(1, regs + ZX2967_THERMAL_POWER_MODE);
> +
> +	/*
> +	 * Calculate temperature
> +	 *   922	initial value of calibration cure
> +	 *   1.951	slope of calibration cure
> +	 */
> +	*temp = DIV_ROUND_CLOSEST((val - 922) * 1000, 1951);
> +
> +	mutex_unlock(&priv->lock);
> +
> +	return 0;
> +}
> +
> +static struct thermal_zone_of_device_ops zx2967_of_thermal_ops = {
> +	.get_temp = zx2967_thermal_get_temp,
> +};
> +
> +static int zx2967_thermal_probe(struct platform_device *pdev)
> +{
> +	struct zx2967_thermal_priv *priv;
> +	struct resource *res;
> +	int ret, i;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	priv->regs = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(priv->regs))
> +		return PTR_ERR(priv->regs);
> +
> +	priv->clk_gate = devm_clk_get(&pdev->dev, "gate");
> +	if (IS_ERR(priv->clk_gate)) {
> +		ret = PTR_ERR(priv->clk_gate);
> +		dev_err(&pdev->dev, "failed to get clock gate: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(priv->clk_gate);
> +	if (ret) {
> +		dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	priv->pclk = devm_clk_get(&pdev->dev, "pclk");
> +	if (IS_ERR(priv->pclk)) {
> +		ret = PTR_ERR(priv->pclk);
> +		dev_err(&pdev->dev, "failed to get apb clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = clk_prepare_enable(priv->pclk);
> +	if (ret) {
> +		clk_disable_unprepare(priv->clk_gate);
> +		dev_err(&pdev->dev, "failed to enable converter clock: %d\n",
> +			ret);
> +		return ret;
> +	}
> +
> +	mutex_init(&priv->lock);
> +	for (i = 0; i < NUM_SENSORS; i++) {
> +		struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
> +
> +		sensor->priv = priv;
> +		sensor->id = i;
> +		sensor->tzd = thermal_zone_of_sensor_register(&pdev->dev,
> +					i, sensor, &zx2967_of_thermal_ops);
> +		if (IS_ERR(sensor->tzd)) {
> +			ret = PTR_ERR(sensor->tzd);
> +			dev_err(&pdev->dev, "failed to register sensor %d: %d\n",
> +				i, ret);
> +			goto remove_ts;
> +		}
> +	}
> +	priv->dev = &pdev->dev;
> +	platform_set_drvdata(pdev, priv);
> +
> +	return 0;
> +
> +remove_ts:
> +	clk_disable_unprepare(priv->clk_gate);
> +	clk_disable_unprepare(priv->pclk);
> +	for (i--; i >= 0; i--)
> +		thermal_zone_of_sensor_unregister(&pdev->dev,
> +						  priv->sensors[i].tzd);
> +
> +	return ret;
> +}
> +
> +static int zx2967_thermal_exit(struct platform_device *pdev)
> +{
> +	struct zx2967_thermal_priv *priv = platform_get_drvdata(pdev);
> +	int i;
> +
> +	for (i = 0; i < NUM_SENSORS; i++) {
> +		struct zx2967_thermal_sensor *sensor = &priv->sensors[i];
> +
> +		thermal_zone_of_sensor_unregister(&pdev->dev, sensor->tzd);
> +	}
> +	clk_disable_unprepare(priv->pclk);
> +	clk_disable_unprepare(priv->clk_gate);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id zx2967_thermal_id_table[] = {
> +	{ .compatible = "zte,zx296718-thermal" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, zx2967_thermal_id_table);
> +
> +static SIMPLE_DEV_PM_OPS(zx2967_thermal_pm_ops,
> +			 zx2967_thermal_suspend, zx2967_thermal_resume);
> +
> +static struct platform_driver zx2967_thermal_driver = {
> +	.probe = zx2967_thermal_probe,
> +	.remove = zx2967_thermal_exit,
> +	.driver = {
> +		.name = "zx2967_thermal",
> +		.of_match_table = zx2967_thermal_id_table,
> +		.pm = &zx2967_thermal_pm_ops,
> +	},
> +};
> +module_platform_driver(zx2967_thermal_driver);
> +
> +MODULE_AUTHOR("Baoyou Xie <baoyou.xie@linaro.org>");
> +MODULE_DESCRIPTION("ZTE zx2967 thermal driver");
> +MODULE_LICENSE("GPL");

GPLv2?

> -- 
> 2.7.4
> 

Re: [PATCH v4 1/3] dt: bindings: add documentation for zx2967 family thermal sensor

[Eduardo Valentin]

Hey,

On Fri, Jan 13, 2017 at 06:46:56PM +0800, Baoyou Xie wrote:
> This patch adds dt-binding documentation for zx2967 family thermal sensor.
> 
> Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
> Acked-by: Rob Herring <robh@kernel.org>
> Reviewed-by: Shawn Guo <shawnguo@kernel.org>
> ---
>  .../devicetree/bindings/thermal/zx2967-thermal.txt  | 21 +++++++++++++++++++++
>  1 file changed, 21 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/zx2967-thermal.txt
> 
> diff --git a/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt b/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt
> new file mode 100644
> index 0000000..86f941c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/zx2967-thermal.txt
> @@ -0,0 +1,21 @@
> +* ZTE zx2967 family Thermal
> +
> +Required Properties:
> +- compatible: should be one of the following.
> +    * zte,zx296718-thermal
> +- reg: physical base address of the controller and length of memory mapped
> +    region.
> +- clocks : Pairs of phandle and specifier referencing the controller's clocks.
> +- clock-names: "gate" for the topcrm clock.
> +	       "pclk" for the apb clock.
> +- #thermal-sensor-cells: must be 0.
> +
> +Example:
> +
> +	tempsensor: tempsensor@148a000 {
> +		compatible = "zte,zx296718-thermal";
> +		reg = <0x0148a000 0x20>;
> +		clocks = <&topcrm TEMPSENSOR_GATE>, <&audiocrm AUDIO_TS_PCLK>;
> +		clock-names = "gate", "pclk";
> +		#thermal-sensor-cells = <0>;
> +	};

Given that you are using of-thermal, would be welcome if you include an
example on how to deploy a thermal zone with your tempsensor entry.

> -- 
> 2.7.4
> 

Re: [PATCH v4 1/3] dt: bindings: add documentation for zx2967 family thermal sensor

[Eduardo Valentin]

On Tue, Jan 17, 2017 at 01:38:48PM +0800, Baoyou Xie wrote:
> On 17 January 2017 at 13:27, Eduardo Valentin <edubezval@gmail.com> wrote:
<cut>
> > It's a good idea:) In fact, we defined some thermal zones and used IPA
> on products.
> 

Cool! Any feedback on using IPA?