Re: [PATCH 8/9] mfd: wm97xx-core: core support for wm97xx Codec

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

On Wed, 26 Oct 2016, Robert Jarzmik wrote:

> The WM9705, WM9712 and WM9713 are highly integrated codecs, with an
> audio codec, DAC and ADC, GPIO unit and a touchscreen interface.
> 
> Historically the support was spread across drivers/input/touchscreen and
> sound/soc/codecs. The sharing was done through ac97 bus sharing. This
> model will not withstand the new AC97 bus model, where codecs are
> discovered on runtime.
> 
> Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
> ---
>  drivers/mfd/Kconfig        |  14 +++
>  drivers/mfd/Makefile       |   1 +
>  drivers/mfd/wm97xx-core.c  | 282 +++++++++++++++++++++++++++++++++++++++++++++
>  include/linux/mfd/wm97xx.h |  31 +++++
>  4 files changed, 328 insertions(+)
>  create mode 100644 drivers/mfd/wm97xx-core.c
>  create mode 100644 include/linux/mfd/wm97xx.h
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index c6df6442ba2b..2ac818127b0a 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1597,6 +1597,20 @@ config MFD_WM8994
>  	  core support for the WM8994, in order to use the actual
>  	  functionaltiy of the device other drivers must be enabled.
>  
> +config MFD_WM97xx
> +	tristate "Wolfson Microelectronics WM97xx"
> +	select MFD_CORE
> +	select REGMAP_AC97
> +	select AC97_BUS_COMPAT if AC97_BUS_NEW
> +	help
> +

Surplus '\n' here.

> +	  The WM9705, WM9712 and WM9713 is a highly integrated hi-fi CODEC
> +	  designed for smartphone applications.  As well as audio functionality
> +	  it has on board GPIO and a touchscreen functionality which is
> +	  supported via the relevant subsystems.  This driver provides core
> +	  support for the WM97xx, in order to use the actual functionaltiy of

Always spell check your work.

> +	  the device other drivers must be enabled.
> +
>  config MFD_STW481X
>  	tristate "Support for ST Microelectronics STw481x"
>  	depends on I2C && (ARCH_NOMADIK || COMPILE_TEST)
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 9834e669d985..5c3534f4c7c3 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -69,6 +69,7 @@ obj-$(CONFIG_MFD_WM8350)	+= wm8350.o
>  obj-$(CONFIG_MFD_WM8350_I2C)	+= wm8350-i2c.o
>  wm8994-objs			:= wm8994-core.o wm8994-irq.o wm8994-regmap.o
>  obj-$(CONFIG_MFD_WM8994)	+= wm8994.o
> +obj-$(CONFIG_MFD_WM97xx)	+= wm97xx-core.o
>  
>  obj-$(CONFIG_TPS6105X)		+= tps6105x.o
>  obj-$(CONFIG_TPS65010)		+= tps65010.o
> diff --git a/drivers/mfd/wm97xx-core.c b/drivers/mfd/wm97xx-core.c
> new file mode 100644
> index 000000000000..f2cd80354b4a
> --- /dev/null
> +++ b/drivers/mfd/wm97xx-core.c
> @@ -0,0 +1,282 @@
> +/*
> + * Wolfson WM97xx -- Core device
> + *
> + * Copyright (C) 2016 Robert Jarzmik
> + *
> + * 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.
> + *
> + * Features:
> + *  - an AC97 audio codec
> + *  - a touchscreen driver
> + *  - a GPIO block

Place this above the Copyright.

> + */
> +
> +#include <linux/module.h>

Why is this seperted?

> +#include <linux/device.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/wm97xx.h>
> +#include <linux/wm97xx.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <sound/ac97/codec.h>
> +#include <sound/ac97/compat.h>

Alphabetical.

> +#define WM9705_VENDOR_ID 0x574d4c05
> +#define WM9712_VENDOR_ID 0x574d4c12
> +#define WM9713_VENDOR_ID 0x574d4c13
> +#define WM97xx_VENDOR_ID_MASK 0xffffffff

Use tabs, not spaces.

These are probably better represented as enums.

> +struct wm97xx_priv {
> +	struct regmap *regmap;
> +	struct snd_ac97 *ac97;
> +	struct device *dev;
> +};

Replace _priv with _ddata.

Also document using kerneldoc.

> +static bool wm97xx_readable_reg(struct device *dev, unsigned int reg)
> +{
> +	switch (reg) {
> +	case AC97_RESET ... AC97_PCM_SURR_DAC_RATE:
> +	case AC97_PCM_LR_ADC_RATE:
> +	case AC97_CENTER_LFE_MASTER:
> +	case AC97_SPDIF ... AC97_LINE1_LEVEL:
> +	case AC97_GPIO_CFG ... 0x5c:

Please define.
> +	case AC97_CODEC_CLASS_REV ... AC97_PCI_SID:
> +	case 0x74 ... AC97_VENDOR_ID2:

As above.

> +	default:
> +		return false;
> +	}
> +}
> +
> +static bool wm97xx_writeable_reg(struct device *dev, unsigned int reg)
> +{
> +	switch (reg) {
> +	case AC97_VENDOR_ID1:
> +	case AC97_VENDOR_ID2:
> +		return false;
> +	default:
> +		return wm97xx_readable_reg(dev, reg);
> +	}
> +}
> +
> +static const struct reg_default wm97xx_reg_defaults[] = {
> +};

What's the point in this?

> +static const struct regmap_config wm9705_regmap_config = {
> +	.reg_bits = 16,
> +	.reg_stride = 2,
> +	.val_bits = 16,
> +	.max_register = 0x7e,
> +	.cache_type = REGCACHE_RBTREE,
> +
> +	.reg_defaults = wm97xx_reg_defaults,
> +	.num_reg_defaults = ARRAY_SIZE(wm97xx_reg_defaults),
> +	.volatile_reg = regmap_ac97_default_volatile,
> +	.readable_reg = wm97xx_readable_reg,
> +	.writeable_reg = wm97xx_writeable_reg,
> +};
> +
> +static const struct regmap_config wm9712_regmap_config = {
> +	.reg_bits = 16,
> +	.reg_stride = 2,
> +	.val_bits = 16,
> +	.max_register = 0x7e,
> +	.cache_type = REGCACHE_RBTREE,
> +
> +	.reg_defaults = wm97xx_reg_defaults,
> +	.num_reg_defaults = ARRAY_SIZE(wm97xx_reg_defaults),
> +	.volatile_reg = regmap_ac97_default_volatile,
> +	.readable_reg = wm97xx_readable_reg,
> +	.writeable_reg = wm97xx_writeable_reg,
> +};
> +
> +static int wm9705_register(struct wm97xx_priv *wm97xx)
> +{
> +	return 0;
> +}
> +
> +static int wm9712_register(struct wm97xx_priv *wm97xx)
> +{
> +	return 0;
> +}

I don't get it?

Either populate or don't provide.

> +static const struct reg_default wm9713_reg_defaults[] = {
> +	{ 0x02, 0x8080 },	/* Speaker Output Volume */
> +	{ 0x04, 0x8080 },	/* Headphone Output Volume */
> +	{ 0x06, 0x8080 },	/* Out3/OUT4 Volume */
> +	{ 0x08, 0xc880 },	/* Mono Volume */
> +	{ 0x0a, 0xe808 },	/* LINEIN Volume */
> +	{ 0x0c, 0xe808 },	/* DAC PGA Volume */
> +	{ 0x0e, 0x0808 },	/* MIC PGA Volume */
> +	{ 0x10, 0x00da },	/* MIC Routing Control */
> +	{ 0x12, 0x8000 },	/* Record PGA Volume */
> +	{ 0x14, 0xd600 },	/* Record Routing */
> +	{ 0x16, 0xaaa0 },	/* PCBEEP Volume */
> +	{ 0x18, 0xaaa0 },	/* VxDAC Volume */
> +	{ 0x1a, 0xaaa0 },	/* AUXDAC Volume */
> +	{ 0x1c, 0x0000 },	/* Output PGA Mux */
> +	{ 0x1e, 0x0000 },	/* DAC 3D control */
> +	{ 0x20, 0x0f0f },	/* DAC Tone Control*/
> +	{ 0x22, 0x0040 },	/* MIC Input Select & Bias */
> +	{ 0x24, 0x0000 },	/* Output Volume Mapping & Jack */
> +	{ 0x26, 0x7f00 },	/* Powerdown Ctrl/Stat*/
> +	{ 0x28, 0x0405 },	/* Extended Audio ID */
> +	{ 0x2a, 0x0410 },	/* Extended Audio Start/Ctrl */
> +	{ 0x2c, 0xbb80 },	/* Audio DACs Sample Rate */
> +	{ 0x2e, 0xbb80 },	/* AUXDAC Sample Rate */
> +	{ 0x32, 0xbb80 },	/* Audio ADCs Sample Rate */
> +	{ 0x36, 0x4523 },	/* PCM codec control */
> +	{ 0x3a, 0x2000 },	/* SPDIF control */
> +	{ 0x3c, 0xfdff },	/* Powerdown 1 */
> +	{ 0x3e, 0xffff },	/* Powerdown 2 */
> +	{ 0x40, 0x0000 },	/* General Purpose */
> +	{ 0x42, 0x0000 },	/* Fast Power-Up Control */
> +	{ 0x44, 0x0080 },	/* MCLK/PLL Control */
> +	{ 0x46, 0x0000 },	/* MCLK/PLL Control */
> +
> +	{ 0x4c, 0xfffe },	/* GPIO Pin Configuration */
> +	{ 0x4e, 0xffff },	/* GPIO Pin Polarity / Type */
> +	{ 0x50, 0x0000 },	/* GPIO Pin Sticky */
> +	{ 0x52, 0x0000 },	/* GPIO Pin Wake-Up */
> +				/* GPIO Pin Status */
> +	{ 0x56, 0xfffe },	/* GPIO Pin Sharing */
> +	{ 0x58, 0x4000 },	/* GPIO PullUp/PullDown */
> +	{ 0x5a, 0x0000 },	/* Additional Functions 1 */
> +	{ 0x5c, 0x0000 },	/* Additional Functions 2 */
> +	{ 0x60, 0xb032 },	/* ALC Control */
> +	{ 0x62, 0x3e00 },	/* ALC / Noise Gate Control */
> +	{ 0x64, 0x0000 },	/* AUXDAC input control */
> +	{ 0x74, 0x0000 },	/* Digitiser Reg 1 */
> +	{ 0x76, 0x0006 },	/* Digitiser Reg 2 */
> +	{ 0x78, 0x0001 },	/* Digitiser Reg 3 */
> +	{ 0x7a, 0x0000 },	/* Digitiser Read Back */
> +};
> +
> +static const struct regmap_config wm9713_regmap_config = {
> +	.reg_bits = 16,
> +	.reg_stride = 2,
> +	.val_bits = 16,
> +	.max_register = 0x7e,
> +	.cache_type = REGCACHE_RBTREE,
> +
> +	.reg_defaults = wm9713_reg_defaults,
> +	.num_reg_defaults = ARRAY_SIZE(wm9713_reg_defaults),
> +	.volatile_reg = regmap_ac97_default_volatile,
> +	.readable_reg = wm97xx_readable_reg,
> +	.writeable_reg = wm97xx_writeable_reg,
> +};
> +
> +static int wm9713_register(struct wm97xx_priv *wm97xx,
> +			   struct wm97xx_pdata *pdata)
> +{

What are you lining this up with?

> +	struct wm97xx_platform_data codec_pdata;
> +	const struct mfd_cell cells[] = {
> +		{
> +			.name = "wm9713-codec",
> +			.platform_data = &codec_pdata,
> +			.pdata_size = sizeof(codec_pdata),
> +		},
> +		{
> +			.name = "wm97xx-ts",
> +			.platform_data = &codec_pdata,
> +			.pdata_size = sizeof(codec_pdata),
> +		},
> +	};
> +
> +	codec_pdata.ac97 = wm97xx->ac97;
> +	codec_pdata.regmap = devm_regmap_init_ac97(wm97xx->ac97,
> +						   &wm9713_regmap_config);
> +	codec_pdata.batt_pdata = pdata->batt_pdata;
> +	if (IS_ERR(codec_pdata.regmap))
> +		return PTR_ERR(codec_pdata.regmap);

This doesn't look like pdata.  You can get rid of all of this hoop
jumping if you add it to ddata and set it as such.

> +	return devm_mfd_add_devices(wm97xx->dev, -1, cells,

Use the defines.

> +				    ARRAY_SIZE(cells), NULL, 0, NULL);
> +}
> +
> +static int wm97xx_ac97_probe(struct ac97_codec_device *adev)

This looks sound specific.

Why isn't this a plane platform driver?

> +{
> +	struct wm97xx_priv *wm97xx;
> +	int ret;
> +	void *pdata = snd_ac97_codec_get_platdata(adev);
> +
> +	wm97xx = devm_kzalloc(ac97_codec_dev2dev(adev),
> +			      sizeof(*wm97xx), GFP_KERNEL);
> +	if (!wm97xx)
> +		return -ENOMEM;
> +
> +	wm97xx->dev = ac97_codec_dev2dev(adev);
> +	wm97xx->ac97 = snd_ac97_compat_alloc(adev);
> +	if (IS_ERR(wm97xx->ac97))
> +		return PTR_ERR(wm97xx->ac97);
> +
> +
> +	ac97_set_drvdata(adev, wm97xx);
> +	dev_info(wm97xx->dev, "wm97xx core found, id=0x%x\n",
> +		 adev->vendor_id);

All of this ac97/sound stuff should be done in the ac97/sound driver.

> +	switch (adev->vendor_id) {
> +	case WM9705_VENDOR_ID:
> +		ret = wm9705_register(wm97xx);
> +		break;
> +	case WM9712_VENDOR_ID:
> +		ret = wm9712_register(wm97xx);
> +		break;
> +	case WM9713_VENDOR_ID:
> +		ret = wm9713_register(wm97xx, pdata);
> +		break;
> +	default:
> +		ret = -ENODEV;
> +	}
> +
> +	if (ret)
> +		snd_ac97_compat_release(wm97xx->ac97);
> +
> +	return ret;
> +}
> +
> +static int wm97xx_ac97_remove(struct ac97_codec_device *adev)
> +{
> +	struct wm97xx_priv *wm97xx = ac97_get_drvdata(adev);
> +
> +	snd_ac97_compat_release(wm97xx->ac97);
> +
> +	return 0;
> +}
> +
> +static const struct ac97_id wm97xx_ac97_ids[] = {
> +	{ .id = WM9705_VENDOR_ID, .mask = WM97xx_VENDOR_ID_MASK },
> +	{ .id = WM9712_VENDOR_ID, .mask = WM97xx_VENDOR_ID_MASK },
> +	{ .id = WM9713_VENDOR_ID, .mask = WM97xx_VENDOR_ID_MASK },
> +	{ }
> +};
> +
> +static struct ac97_codec_driver wm97x3_ac97_driver = {
> +	.driver = {
> +		.name = "wm97xx-core",
> +	},
> +	.probe		= wm97xx_ac97_probe,
> +	.remove		= wm97xx_ac97_remove,
> +	.id_table	= wm97xx_ac97_ids,
> +};
> +
> +static int __init wm97xx_module_init(void)
> +{
> +	return snd_ac97_codec_driver_register(&wm97x3_ac97_driver);
> +}
> +module_init(wm97xx_module_init);
> +
> +static void __exit wm97xx_module_exit(void)
> +{
> +	snd_ac97_codec_driver_unregister(&wm97x3_ac97_driver);
> +}
> +module_exit(wm97xx_module_exit);
> +
> +MODULE_DESCRIPTION("WM9712, WM9713 core driver");
> +MODULE_AUTHOR("Robert Jarzmik <robert.jarzmik@free.fr>");
> +MODULE_LICENSE("GPL");
> +
> diff --git a/include/linux/mfd/wm97xx.h b/include/linux/mfd/wm97xx.h
> new file mode 100644
> index 000000000000..627322f14d48
> --- /dev/null
> +++ b/include/linux/mfd/wm97xx.h
> @@ -0,0 +1,31 @@
> +/*
> + * wm97xx client interface
> + *
> + * Copyright (C) 2016 Robert Jarzmik
> + *
> + * 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.
> + */
> +
> +#ifndef __LINUX_MFD_WM97XX_H
> +#define __LINUX_MFD_WM97XX_H
> +
> +struct regmap;
> +struct wm97xx_batt_pdata;
> +struct snd_ac97;

Why can't you just add the include files?

> +struct wm97xx_platform_data {
> +	struct snd_ac97 *ac97;
> +	struct regmap *regmap;
> +	struct wm97xx_batt_pdata *batt_pdata;
> +};
> +
> +
> +#endif

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