[PATCH v6 2/2] Regulator: Add Anatop regulator driver

Shawn Guo shawn.guo at linaro.org
Sun Mar 4 06:51:48 UTC 2012


On Fri, Mar 02, 2012 at 03:00:41PM +0800, Ying-Chun Liu (PaulLiu) wrote:
> From: "Ying-Chun Liu (PaulLiu)" <paul.liu at linaro.org>
> 
> Anatop is an integrated regulator inside i.MX6 SoC.
> There are 3 digital regulators which controls PU, CORE (ARM), and SOC.
> And 3 analog regulators which controls 1P1, 2P5, 3P0 (USB).
> This patch adds the Anatop regulator driver.
> 
> Signed-off-by: Nancy Chen <Nancy.Chen at freescale.com>
> Signed-off-by: Ying-Chun Liu (PaulLiu) <paul.liu at linaro.org>
> Cc: Mark Brown <broonie at opensource.wolfsonmicro.com>
> Cc: Liam Girdwood <lrg at ti.com>
> Cc: Samuel Ortiz <sameo at linux.intel.com>
> Cc: Shawn Guo <shawn.guo at linaro.org>
> ---
>  .../bindings/regulator/anatop-regulator.txt        |   28 +++
>  drivers/regulator/Kconfig                          |    6 +
>  drivers/regulator/Makefile                         |    1 +
>  drivers/regulator/anatop-regulator.c               |  205 ++++++++++++++++++++
>  include/linux/regulator/anatop-regulator.h         |   40 ++++
>  5 files changed, 280 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/regulator/anatop-regulator.txt
>  create mode 100644 drivers/regulator/anatop-regulator.c
>  create mode 100644 include/linux/regulator/anatop-regulator.h
> 
> diff --git a/Documentation/devicetree/bindings/regulator/anatop-regulator.txt b/Documentation/devicetree/bindings/regulator/anatop-regulator.txt
> new file mode 100644
> index 0000000..f19cfea
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/regulator/anatop-regulator.txt
> @@ -0,0 +1,28 @@
> +Anatop Voltage regulators
> +
> +Required properties:
> +- compatible: Must be "fsl,anatop-regulator"
> +- vol-bit-shift: Bit shift for the register
> +- vol-bit-size: Number of bits used in the register

A better name might be vol-bit-width, considering shift and width
are generally a couple.

> +- min-bit-val: Minimum value of this register
> +- min-voltage: Minimum voltage of this regulator
> +- max-voltage: Maximum voltage of this regulator
> +
> +Any property defined as part of the core regulator
> +binding, defined in regulator.txt, can also be used.
> +
> +Example:
> +
> +	reg_vddpu: regulator-vddpu at 140 {
> +		compatible = "fsl,anatop-regulator";
> +		regulator-name = "vddpu";
> +		regulator-min-microvolt = <725000>;
> +		regulator-max-microvolt = <1300000>;
> +		regulator-always-on;
> +		reg = <0x140 1>;

The size cell is useless and confusing here.  I think we can just have
it like "reg = <0x140>;".

> +		vol-bit-shift = <9>;
> +		vol-bit-size = <5>;
> +		min-bit-val = <1>;
> +		min-voltage = <725000>;
> +		max-voltage = <1300000>;
> +	};
> diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
> index 7a61b17..5fbcda2 100644
> --- a/drivers/regulator/Kconfig
> +++ b/drivers/regulator/Kconfig
> @@ -335,5 +335,11 @@ config REGULATOR_AAT2870
>  	  If you have a AnalogicTech AAT2870 say Y to enable the
>  	  regulator driver.
>  
> +config REGULATOR_ANATOP
> +	tristate "ANATOP LDO regulators"

A more descriptive prompt?

> +	depends on MFD_ANATOP
> +	help
> +	  Say y here to support ANATOP LDOs regulators.

Ditto.

> +
>  endif
>  
> diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
> index 503bac8..8440871 100644
> --- a/drivers/regulator/Makefile
> +++ b/drivers/regulator/Makefile
> @@ -48,5 +48,6 @@ obj-$(CONFIG_REGULATOR_AB8500)	+= ab8500.o
>  obj-$(CONFIG_REGULATOR_DB8500_PRCMU) += db8500-prcmu.o
>  obj-$(CONFIG_REGULATOR_TPS65910) += tps65910-regulator.o
>  obj-$(CONFIG_REGULATOR_AAT2870) += aat2870-regulator.o
> +obj-$(CONFIG_REGULATOR_ANATOP) += anatop-regulator.o
>  
>  ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG
> diff --git a/drivers/regulator/anatop-regulator.c b/drivers/regulator/anatop-regulator.c
> new file mode 100644
> index 0000000..84d8f50
> --- /dev/null
> +++ b/drivers/regulator/anatop-regulator.c
> @@ -0,0 +1,205 @@
> +/*
> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
> + */
> +
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> +
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> +
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +
> +#include <linux/slab.h>
> +#include <linux/device.h>
> +#include <linux/module.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/platform_device.h>
> +#include <linux/regulator/driver.h>
> +#include <linux/regulator/anatop-regulator.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/regulator/of_regulator.h>

It may be good to have <linux/regulator/*> headers grouped/sorted
together, something like:

#include <linux/regulator/anatop-regulator.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>

> +
> +static int anatop_set_voltage(struct regulator_dev *reg, int min_uV,
> +				  int max_uV, unsigned *selector)
> +{
> +	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
> +	u32 val, sel;
> +	int uv;
> +
> +	uv = min_uV;
> +	dev_dbg(&reg->dev, "%s: uv %d, min %d, max %d\n", __func__,
> +		uv, anatop_reg->min_voltage,
> +		anatop_reg->max_voltage);
> +
> +	if (uv < anatop_reg->min_voltage) {
> +		if (max_uV > anatop_reg->min_voltage)
> +			uv = anatop_reg->min_voltage;
> +		else
> +			return -EINVAL;
> +	}
> +
> +	if (anatop_reg->control_reg) {
> +		sel = (uv - anatop_reg->min_voltage) / 25000;
> +		if (sel * 25000 + anatop_reg->min_voltage
> +		    > anatop_reg->max_voltage)
> +			return -EINVAL;
> +		val = anatop_reg->min_bit_val + sel;
> +		*selector = sel;
> +		dev_dbg(&reg->dev, "%s: calculated val %d\n", __func__, val);
> +		anatop_set_bits(anatop_reg->mfd,
> +				anatop_reg->control_reg,
> +				anatop_reg->vol_bit_shift,
> +				anatop_reg->vol_bit_size,
> +				val);
> +		return 0;
> +	} else {
> +		return -ENOTSUPP;
> +	}
> +}
> +
> +static int anatop_get_voltage_sel(struct regulator_dev *reg)
> +{
> +	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
> +	int selector;
> +
> +	if (anatop_reg->control_reg) {
> +		u32 val = anatop_get_bits(anatop_reg->mfd,
> +					  anatop_reg->control_reg,
> +					  anatop_reg->vol_bit_shift,
> +					  anatop_reg->vol_bit_size);
> +		selector = val - anatop_reg->min_bit_val;
> +		return selector;
> +	} else {
> +		return -ENOTSUPP;
> +	}
> +}
> +
> +static int anatop_list_voltage(struct regulator_dev *reg, unsigned selector)
> +{
> +	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
> +	int uv;
> +
> +	uv = anatop_reg->min_voltage + selector * 25000;
> +	dev_dbg(&reg->dev, "vddio = %d, selector = %u\n", uv, selector);
> +
> +	return uv;
> +}
> +
> +static struct regulator_ops anatop_rops = {
> +	.set_voltage     = anatop_set_voltage,
> +	.get_voltage_sel = anatop_get_voltage_sel,
> +	.list_voltage    = anatop_list_voltage,
> +};
> +
> +int anatop_regulator_probe(struct platform_device *pdev)

static int __devinit

> +{
> +	struct device *dev = &pdev->dev;
> +	struct device_node *np = dev->of_node;
> +	struct regulator_desc *rdesc;
> +	struct regulator_dev *rdev;
> +	struct anatop_regulator *sreg;
> +	struct regulator_init_data *initdata;
> +	struct anatop *anatopmfd = dev_get_drvdata(pdev->dev.parent);
> +	const __be32 *rval;
> +	u64 ofsize;
> +
> +	initdata = of_get_regulator_init_data(dev, dev->of_node);

You already have a variable np being dev->of_node.

> +	sreg = devm_kzalloc(dev, sizeof(struct anatop_regulator), GFP_KERNEL);
> +	if (!sreg)
> +		return -EINVAL;
> +	rdesc = devm_kzalloc(dev, sizeof(struct regulator_desc), GFP_KERNEL);
> +	if (!rdesc)
> +		return -EINVAL;

Would something like the following be better?

	sreg = devm_kzalloc(dev, sizeof(*sreg) + sizeof(*rdesc), GFP_KERNEL);
	if (!sreg)
		return -ENOMEM;
	rdesc = (struct regulator_desc *)(sreg + 1);

> +	sreg->initdata = initdata;
> +	sreg->name = kstrdup(of_get_property(np, "regulator-name", NULL),
> +			     GFP_KERNEL);
> +	sreg->regulator = rdesc;
> +	memset(rdesc, 0, sizeof(struct regulator_desc));

sizeof(*rdesc)

> +	rdesc->name = sreg->name;
> +	rdesc->ops = &anatop_rops;
> +	rdesc->type = REGULATOR_VOLTAGE;
> +	rdesc->owner = THIS_MODULE;
> +	sreg->mfd = anatopmfd;
> +	rval = of_get_address(np, 0, &ofsize, NULL);
> +	if (rval)
> +		sreg->control_reg = be32_to_cpu(*rval);

With size cell removed, we can just read the "reg" property as an u32
with helper function of_property_read_u32().

> +	rval = of_get_property(np, "vol-bit-size", NULL);
> +	if (rval)
> +		sreg->vol_bit_size = be32_to_cpu(*rval);
> +	rval = of_get_property(np, "vol-bit-shift", NULL);
> +	if (rval)
> +		sreg->vol_bit_shift = be32_to_cpu(*rval);
> +	rval = of_get_property(np, "min-bit-val", NULL);
> +	if (rval)
> +		sreg->min_bit_val = be32_to_cpu(*rval);
> +	rval = of_get_property(np, "min-voltage", NULL);
> +	if (rval)
> +		sreg->min_voltage = be32_to_cpu(*rval);
> +	rval = of_get_property(np, "max-voltage", NULL);
> +	if (rval)
> +		sreg->max_voltage = be32_to_cpu(*rval);

All above can just use of_property_read_u32().

> +
> +	/* register regulator */
> +	rdev = regulator_register(rdesc, &pdev->dev,
> +				  initdata, sreg, pdev->dev.of_node);
> +	platform_set_drvdata(pdev, rdev);
> +
> +	if (IS_ERR(rdev)) {
> +		dev_err(&pdev->dev, "failed to register %s\n",
> +			rdesc->name);
> +		kfree(sreg->name);
> +		return PTR_ERR(rdev);
> +	}

Shouldn't the error checking go right after regulator_register() call?

> +
> +	return 0;
> +}
> +
> +int anatop_regulator_remove(struct platform_device *pdev)

static int __devexit

> +{
> +	struct regulator_dev *rdev = platform_get_drvdata(pdev);
> +	struct anatop_regulator *sreg = rdev_get_drvdata(rdev);
> +	kfree(sreg->name);
> +	regulator_unregister(rdev);
> +	return 0;
> +}
> +
> +struct of_device_id __devinitdata of_anatop_regulator_match_tbl[] = {

static

> +	{ .compatible = "fsl,anatop-regulator", },
> +	{ /* end */ }
> +};
> +
> +struct platform_driver anatop_regulator = {

static

> +	.driver = {
> +		.name	= "anatop_regulator",
> +		.owner  = THIS_MODULE,
> +		.of_match_table = of_anatop_regulator_match_tbl,
> +	},
> +	.probe	= anatop_regulator_probe,
> +	.remove	= anatop_regulator_remove,
> +};
> +
> +int anatop_regulator_init(void)

static int __init

> +{
> +	return platform_driver_register(&anatop_regulator);
> +}
> +postcore_initcall(anatop_regulator_init);
> +
> +void anatop_regulator_exit(void)

static void __exit

> +{
> +	platform_driver_unregister(&anatop_regulator);
> +}
> +module_exit(anatop_regulator_exit);
> +
> +MODULE_DESCRIPTION("ANATOP Regulator driver");
> +MODULE_LICENSE("GPL v2");

MODULE_AUTHOR?  Multiple people can be listed there.

> diff --git a/include/linux/regulator/anatop-regulator.h b/include/linux/regulator/anatop-regulator.h
> new file mode 100644
> index 0000000..7a9a05b
> --- /dev/null
> +++ b/include/linux/regulator/anatop-regulator.h
> @@ -0,0 +1,40 @@
> +/*
> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
> + */
> +
> +/*
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> +
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> +
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +
> +#ifndef __ANATOP_REGULATOR_H
> +#define __ANATOP_REGULATOR_H
> +
> +#include <linux/regulator/driver.h>
> +#include <linux/mfd/anatop.h>
> +
> +struct anatop_regulator {
> +	struct regulator_desc *regulator;
> +	struct regulator_init_data *initdata;
> +	const char *name;
> +	u32 control_reg;
> +	struct anatop *mfd;
> +	int vol_bit_shift;
> +	int vol_bit_size;
> +	int min_bit_val;
> +	int min_voltage;
> +	int max_voltage;
> +};

Does this structure really need to be public?

> +
> +#endif /* __ANATOP_REGULATOR_H */
> -- 
> 1.7.9.1
> 

-- 
Regards,
Shawn



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