Re: [PATCH v5 3/5] mfd: hi655x: Add hi665x pmic driver

[Lee Jones <lee.jones@linaro.org>]

On Mon, 11 Jan 2016, Chen Feng wrote:

> Add pmic mfd driver to support hisilicon hi665x.

PMIC MFD

> Signed-off-by: Chen Feng <puck.chen@hisilicon.com>
> Signed-off-by: Fei Wang <w.f@huawei.com>
> Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com>
> ---
>  drivers/mfd/Kconfig             |  10 +++
>  drivers/mfd/Makefile            |   1 +
>  drivers/mfd/hi655x-pmic.c       | 169 ++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/hi655x-pmic.h |  56 +++++++++++++
>  4 files changed, 236 insertions(+)
>  create mode 100644 drivers/mfd/hi655x-pmic.c
>  create mode 100644 include/linux/mfd/hi655x-pmic.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 4d92df6..299d972 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -284,6 +284,16 @@ config MFD_HI6421_PMIC
>  	  menus in order to enable them.
>  	  We communicate with the Hi6421 via memory-mapped I/O.
>  
> +config MFD_HI655X_PMIC
> +	tristate "HiSilicon Hi655X series PMU/Codec IC"
> +	depends on ARCH_HISI || (COMPILE_TEST && ARM64)

Why not just COMPILE_TEST?

> +	depends on OF

So this will not COMPILE_TEST if OF is not enabled.

> +	select MFD_CORE
> +	select REGMAP_MMIO
> +	select REGMAP_IRQ
> +	help
> +	  Select this option to enable Hisilicon hi655x series pmic driver.
> +
>  config HTC_EGPIO
>  	bool "HTC EGPIO support"
>  	depends on GPIOLIB && ARM
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index a8b76b8..6a7b0e1 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -186,6 +186,7 @@ obj-$(CONFIG_MFD_STW481X)	+= stw481x.o
>  obj-$(CONFIG_MFD_IPAQ_MICRO)	+= ipaq-micro.o
>  obj-$(CONFIG_MFD_MENF21BMC)	+= menf21bmc.o
>  obj-$(CONFIG_MFD_HI6421_PMIC)	+= hi6421-pmic-core.o
> +obj-$(CONFIG_MFD_HI655X_PMIC)   += hi655x-pmic.o
>  obj-$(CONFIG_MFD_DLN2)		+= dln2.o
>  obj-$(CONFIG_MFD_RT5033)	+= rt5033.o
>  obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o
> diff --git a/drivers/mfd/hi655x-pmic.c b/drivers/mfd/hi655x-pmic.c
> new file mode 100644
> index 0000000..aab18f7
> --- /dev/null
> +++ b/drivers/mfd/hi655x-pmic.c
> @@ -0,0 +1,169 @@
> +/*
> + * Device driver for regulators in hi655x IC

We know it's a device driver.  And I hope it's not a regulator driver.

> + * Copyright (c) 2016 Hisilicon.
> + *
> + * Chen Feng <puck.chen@hisilicon.com>
> + * Fei  Wang <w.f@huawei.com>

Author(s): 

> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/io.h>
> +#include <linux/interrupt.h>
> +#include <linux/init.h>
> +#include <linux/gpio.h>
> +#include <linux/of_gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/hi655x-pmic.h>
> +#include <linux/regmap.h>

Alphabetical please.

> +static const struct mfd_cell hi655x_pmic_devs[] = {
> +	{ .name = "hi655x-regulator", },
> +};

What other devices are there?

> +static const struct regmap_irq hi655x_irqs[] = {
> +	{ .reg_offset = 0, .mask = OTMP_D1R_INT },
> +	{ .reg_offset = 0, .mask = VSYS_2P5_R_INT },
> +	{ .reg_offset = 0, .mask = VSYS_UV_D3R_INT },
> +	{ .reg_offset = 0, .mask = VSYS_6P0_D200UR_INT },
> +	{ .reg_offset = 0, .mask = PWRON_D4SR_INT },
> +	{ .reg_offset = 0, .mask = PWRON_D20F_INT },
> +	{ .reg_offset = 0, .mask = PWRON_D20R_INT },
> +	{ .reg_offset = 0, .mask = RESERVE_INT },
> +};
> +
> +static const struct regmap_irq_chip hi655x_irq_chip = {
> +	.name = "hi655x-pmic",
> +	.irqs = hi655x_irqs,
> +	.num_regs = 1,
> +	.num_irqs = ARRAY_SIZE(hi655x_irqs),
> +	.status_base = HI655X_IRQ_STAT_BASE,
> +	.mask_base = HI655X_IRQ_MASK_BASE,
> +};
> +
> +static unsigned int hi655x_pmic_get_version(struct hi655x_pmic *pmic)
> +{
> +	u32 val;
> +
> +	regmap_read(pmic->regmap,
> +		    HI655X_BUS_ADDR(HI655X_VER_REG), &val);
> +
> +	return val;
> +}

This is a small function that you only use once.

Probably better just to call regmap_read() directly from below.

> +static struct regmap_config hi655x_regmap_config = {
> +	.reg_bits = 32,
> +	.reg_stride = HI655X_STRIDE,
> +	.val_bits = 8,
> +	.max_register = HI655X_BUS_ADDR(0xFFF),
> +};
> +
> +static void hi655x_local_irq_clear(struct regmap *map)
> +{
> +	int i;
> +
> +	regmap_write(map, HI655X_ANA_IRQM_BASE, HI655X_IRQ_CLR);
> +	for (i = 0; i < HI655X_IRQ_ARRAY; i++) {
> +		regmap_write(map, HI655X_IRQ_STAT_BASE + i * HI655X_STRIDE,
> +			     HI655X_IRQ_CLR);
> +	}
> +}
> +
> +static int hi655x_pmic_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct hi655x_pmic *pmic;
> +	struct device *dev = &pdev->dev;
> +	struct device_node *np = dev->of_node;
> +	void __iomem *base;
> +
> +	pmic = devm_kzalloc(dev, sizeof(*pmic), GFP_KERNEL);

You need a NULL check here.

> +	pmic->dev = dev;
> +
> +	pmic->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!pmic->res) {
> +		dev_err(dev, "platform_get_resource err\n");

This is not a good error message.

Besides, we don't normally try to catch this error, as it's checked
for you in devm_ioremap_resource().

> +		return -ENOENT;
> +	}

'\n' here.

> +	base = devm_ioremap_resource(dev, pmic->res);
> +	if (!base) {
> +		dev_err(dev, "cannot map register memory\n");

devm_ioremap_resource() already prints a message on error.  No need
for this.

> +		return -ENOMEM;
> +	}
> +	pmic->regmap = devm_regmap_init_mmio_clk(dev, NULL, base,
> +						 &hi655x_regmap_config);

You need to check for an error here.

> +	pmic->ver = hi655x_pmic_get_version(pmic);
> +	if ((pmic->ver < PMU_VER_START) || (pmic->ver > PMU_VER_END)) {
> +		dev_warn(dev, "it is wrong pmu version\n");

You can't issue a _warn, then return an error.  Please use _err.

... and change to "PMU version %d unsupported".

> +		return -EINVAL;
> +	}
> +
> +	hi655x_local_irq_clear(pmic->regmap);
> +
> +	pmic->gpio = of_get_named_gpio(np, "pmic-gpios", 0);
> +	if (!gpio_is_valid(pmic->gpio)) {
> +		dev_err(dev, "cannot get the pmic-gpios\n");
> +		return -ENODEV;
> +	}
> +
> +	ret = devm_gpio_request_one(dev, pmic->gpio, GPIOF_IN,
> +				    "hi655x_pmic_irq");
> +	if (ret < 0) {
> +		dev_err(dev, "failed to request gpio %d  ret = %d\n",

More readable if you use the IRQ name, as you know it.

"Failed to obtain 'hi655x_pmic_irq'"

> +			pmic->gpio, ret);
> +		return ret;
> +	}
> +
> +	ret = regmap_add_irq_chip(pmic->regmap, gpio_to_irq(pmic->gpio),
> +				  IRQF_TRIGGER_LOW | IRQF_NO_SUSPEND, 0,
> +				  &hi655x_irq_chip, &pmic->irq_data);
> +	if (ret) {
> +		dev_err(dev, "add pmic irq chip error! ret %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* bind pmic to device */

"Bind PMIC to device"

It would be better if you dropped the comment completely to be honest.

> +	platform_set_drvdata(pdev, pmic);
> +
> +	ret = mfd_add_devices(dev, 0, hi655x_pmic_devs,

Please use the #defines for the second parameter.

> +			      ARRAY_SIZE(hi655x_pmic_devs), NULL, 0, NULL);
> +	if (ret) {
> +		dev_err(dev, "add mfd devices failed: %d\n", ret);

"Failed to register device".

> +		regmap_del_irq_chip(pmic->irq, pmic->irq_data);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int hi655x_pmic_remove(struct platform_device *pdev)
> +{
> +	mfd_remove_devices(&pdev->dev);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id of_hi655x_pmic_match_tbl[] = {
> +	{ .compatible = "hisilicon,hi655x-pmic", },
> +	{},
> +};
> +
> +static struct platform_driver hi655x_pmic_driver = {
> +	.driver	= {
> +		.name =	"hi655x-pmic",
> +		.of_match_table = of_hi655x_pmic_match_tbl,

of_match_ptr()

> +	},
> +	.probe  = hi655x_pmic_probe,
> +	.remove = hi655x_pmic_remove,
> +};
> +module_platform_driver(hi655x_pmic_driver);
> +
> +MODULE_AUTHOR("Chen Feng <puck.chen@hisilicon.com>");
> +MODULE_DESCRIPTION("Hisilicon hi655x pmic driver");

PMIC

> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/mfd/hi655x-pmic.h b/include/linux/mfd/hi655x-pmic.h
> new file mode 100644
> index 0000000..e1af0a1
> --- /dev/null
> +++ b/include/linux/mfd/hi655x-pmic.h
> @@ -0,0 +1,56 @@
> +/*
> + * Device driver for regulators in hi655x IC
> + *
> + * Copyright (c) 2016 Hisilicon.
> + *
> + * Chen Feng <puck.chen@hisilicon.com>
> + * Fei  Wang <w.f@huawei.com>

Author(s):

> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#ifndef __HI655X_PMIC_H
> +#define __HI655X_PMIC_H
> +
> +/* Hi655x registers are mapped to memory bus in 4 bytes stride */
> +#define HI655X_STRIDE                   (4)
> +#define HI655X_BUS_ADDR(x)              ((x) << 2)
> +
> +#define HI655X_BITS                     (8)
> +
> +#define HI655X_NR_IRQ                   (32)
> +
> +#define HI655X_IRQ_STAT_BASE            (0x003 << 2)
> +#define HI655X_IRQ_MASK_BASE            (0x007 << 2)
> +#define HI655X_ANA_IRQM_BASE            (0x1b5 << 2)
> +#define HI655X_IRQ_ARRAY                (4)
> +#define HI655X_IRQ_MASK                 (0xFF)
> +#define HI655X_IRQ_CLR                  (0xFF)
> +#define HI655X_VER_REG                  (0x00)
> +
> +#define PMU_VER_START                   (0x10)
> +#define PMU_VER_END                     (0x38)
> +
> +#define RESERVE_INT                     (BIT(7))
> +#define PWRON_D20R_INT                  (BIT(6))
> +#define PWRON_D20F_INT                  (BIT(5))
> +#define PWRON_D4SR_INT                  (BIT(4))
> +#define VSYS_6P0_D200UR_INT             (BIT(3))
> +#define VSYS_UV_D3R_INT                 (BIT(2))
> +#define VSYS_2P5_R_INT                  (BIT(1))
> +#define OTMP_D1R_INT                    (BIT(0))

No need for the extra ()'s

> +struct hi655x_pmic {
> +	struct resource *res;
> +	struct device *dev;
> +	struct regmap *regmap;
> +	struct clk *clk;

Is this used?

> +	int irq;
> +	int gpio;
> +	unsigned int ver;
> +	struct regmap_irq_chip_data *irq_data;
> +};

Check to see if they are all used.

> +#endif

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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