Re: [RFC PATCH 1/4] mfd: Add support for AC200

Lee Jones
2020-04-24T08:05:23Z

On Thu, 16 Apr 2020, Jernej Skrabec wrote:

> This adds support for AC200 multi functional IC. It can be packaged
> standalone or copackaged with SoC like Allwinner H6.
>
> It has analog audio codec, CVBS encoder, RTC and Fast Ethernet PHY.
> Documentation also mention eFuses, but it seems that it's not used in
> copackaged variant.
>
> Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net>
> ---
> drivers/mfd/Kconfig | 9 ++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/ac200.c | 188 ++++++++++++++++++++++++++++++++++
> include/linux/mfd/ac200.h | 210 ++++++++++++++++++++++++++++++++++++++
> 4 files changed, 408 insertions(+)
> create mode 100644 drivers/mfd/ac200.c
> create mode 100644 include/linux/mfd/ac200.h
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 0a59249198d3..1d6b7f3ae193 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -178,6 +178,15 @@ config MFD_AC100
> This driver include only the core APIs. You have to select individual
> components like codecs or RTC under the corresponding menus.
>
> +config MFD_AC200
> + tristate "X-Powers AC200"
> + select MFD_CORE
> + depends on I2C
> + help
> + If you say Y here you get support for the X-Powers AC200 IC.

Please describe the IC here.

> + This driver include only the core APIs. You have to select individual
> + components like Ethernet PHY or RTC under the corresponding menus.
> +
> config MFD_AXP20X
> tristate
> select MFD_CORE
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index f935d10cbf0f..a20407290d6f 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -142,6 +142,7 @@ obj-$(CONFIG_MFD_DA9052_SPI) += da9052-spi.o
> obj-$(CONFIG_MFD_DA9052_I2C) += da9052-i2c.o
>
> obj-$(CONFIG_MFD_AC100) += ac100.o
> +obj-$(CONFIG_MFD_AC200) += ac200.o
> obj-$(CONFIG_MFD_AXP20X) += axp20x.o
> obj-$(CONFIG_MFD_AXP20X_I2C) += axp20x-i2c.o
> obj-$(CONFIG_MFD_AXP20X_RSB) += axp20x-rsb.o
> diff --git a/drivers/mfd/ac200.c b/drivers/mfd/ac200.c
> new file mode 100644
> index 000000000000..cf2710b84879
> --- /dev/null
> +++ b/drivers/mfd/ac200.c
> @@ -0,0 +1,188 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * MFD core driver for X-Powers' AC200 IC
> + *
> + * The AC200 is a chip which is co-packaged with Allwinner H6 SoC and
> + * includes analog audio codec, analog TV encoder, ethernet PHY, eFuse
> + * and RTC.
> + *
> + * Copyright (c) 2020 Jernej Skrabec <jernej.skrabec@siol.net>

This usually goes higher in the header comment.

> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mfd/ac200.h>
> +#include <linux/module.h>
> +#include <linux/of.h>

Alphabetical.

> +/* Interrupts */
> +#define AC200_IRQ_RTC 0
> +#define AC200_IRQ_EPHY 1
> +#define AC200_IRQ_TVE 2
> +
> +/* IRQ enable register */
> +#define AC200_SYS_IRQ_ENABLE_OUT_EN BIT(15)
> +#define AC200_SYS_IRQ_ENABLE_RTC BIT(12)
> +#define AC200_SYS_IRQ_ENABLE_EPHY BIT(8)
> +#define AC200_SYS_IRQ_ENABLE_TVE BIT(4)
> +
> +static const struct regmap_range_cfg ac200_range_cfg[] = {
> + {
> + .range_min = AC200_SYS_VERSION,
> + .range_max = AC200_IC_CHARA1,
> + .selector_reg = AC200_TWI_REG_ADDR_H,
> + .selector_mask = 0xff,
> + .selector_shift = 0,
> + .window_start = 0,
> + .window_len = 256,
> + }
> +};
> +
> +static const struct regmap_config ac200_regmap_config = {
> + .reg_bits = 8,
> + .val_bits = 16,
> + .ranges = ac200_range_cfg,
> + .num_ranges = ARRAY_SIZE(ac200_range_cfg),
> + .max_register = AC200_IC_CHARA1,
> +};
> +
> +static const struct regmap_irq ac200_regmap_irqs[] = {
> + REGMAP_IRQ_REG(AC200_IRQ_RTC, 0, AC200_SYS_IRQ_ENABLE_RTC),
> + REGMAP_IRQ_REG(AC200_IRQ_EPHY, 0, AC200_SYS_IRQ_ENABLE_EPHY),
> + REGMAP_IRQ_REG(AC200_IRQ_TVE, 0, AC200_SYS_IRQ_ENABLE_TVE),
> +};
> +
> +static const struct regmap_irq_chip ac200_regmap_irq_chip = {
> + .name = "ac200_irq_chip",
> + .status_base = AC200_SYS_IRQ_STATUS,
> + .mask_base = AC200_SYS_IRQ_ENABLE,
> + .mask_invert = true,
> + .irqs = ac200_regmap_irqs,
> + .num_irqs = ARRAY_SIZE(ac200_regmap_irqs),
> + .num_regs = 1,
> +};
> +
> +static const struct resource ephy_resource[] = {
> + DEFINE_RES_IRQ(AC200_IRQ_EPHY),
> +};
> +
> +static const struct mfd_cell ac200_cells[] = {
> + {
> + .name = "ac200-ephy",
> + .num_resources = ARRAY_SIZE(ephy_resource),
> + .resources = ephy_resource,
> + .of_compatible = "x-powers,ac200-ephy",
> + },
> +};

Where are the reset of the devices?

> +static int ac200_i2c_probe(struct i2c_client *i2c,
> + const struct i2c_device_id *id)
> +{
> + struct device *dev = &i2c->dev;
> + struct ac200_dev *ac200;

struct ac200_ddata *ddata;

> + int ret;
> +
> + ac200 = devm_kzalloc(dev, sizeof(*ac200), GFP_KERNEL);
> + if (!ac200)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(i2c, ac200);
> +
> + ac200->regmap = devm_regmap_init_i2c(i2c, &ac200_regmap_config);
> + if (IS_ERR(ac200->regmap)) {
> + dev_err(dev, "regmap init failed\n");
> + return PTR_ERR(ac200->regmap);
> + }
> +
> + ac200->clk = devm_clk_get(dev, NULL);
> + if (IS_ERR(ac200->clk)) {
> + dev_err(dev, "Can't obtain the clock!\n");
> + return PTR_ERR(ac200->clk);
> + }
> +
> + ret = clk_prepare_enable(ac200->clk);
> + if (ret)
> + return ret;
> +
> + /* do a reset to put chip in a known state */

If you define the magic values here, this comment become superfluous.

> + ret = regmap_write(ac200->regmap, AC200_SYS_CONTROL, 0);
> + if (ret)
> + goto err_free_clk;
> +
> + ret = regmap_write(ac200->regmap, AC200_SYS_CONTROL, 1);
> + if (ret)
> + goto err_free_clk;
> +
> + /* enable interrupt pin */

This comment can be dropped.

> + ret = regmap_write(ac200->regmap, AC200_SYS_IRQ_ENABLE,
> + AC200_SYS_IRQ_ENABLE_OUT_EN);
> + if (ret)
> + goto err_free_clk;
> +
> + ret = regmap_add_irq_chip(ac200->regmap, i2c->irq, IRQF_ONESHOT, 0,
> + &ac200_regmap_irq_chip, &ac200->regmap_irqc);
> + if (ret)
> + goto err_free_clk;
> +
> + ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, ac200_cells,
> + ARRAY_SIZE(ac200_cells), NULL, 0, NULL);
> + if (ret) {
> + dev_err(dev, "failed to add MFD devices: %d\n", ret);

"Failed to register child devices"

> + goto err_del_irq_chip;
> + }

Do you want to leave the clock running when you leave?

Seems wasteful.

> + return 0;
> +
> +err_del_irq_chip:
> + regmap_del_irq_chip(i2c->irq, ac200->regmap_irqc);

Use the devm_* version, then you do not have to clear up.

> +err_free_clk:
> + clk_disable_unprepare(ac200->clk);
> +
> + return ret;
> +}
> +
> +static int ac200_i2c_remove(struct i2c_client *i2c)
> +{
> + struct ac200_dev *ac200 = i2c_get_clientdata(i2c);
> +
> + /* put chip in reset state */

Use defines, then remove the comment.

> + regmap_write(ac200->regmap, AC200_SYS_CONTROL, 0);
> +
> + mfd_remove_devices(&i2c->dev);

Use devm_* instead.

> + regmap_del_irq_chip(i2c->irq, ac200->regmap_irqc);

Use devm_* instead.

> + clk_disable_unprepare(ac200->clk);
> +
> + return 0;
> +}
> +
> +static const struct i2c_device_id ac200_ids[] = {
> + { "ac200", },
> + { /* sentinel */ }

No need for this comment.

In fact, no need for this table. It can be removed.

> +};
> +MODULE_DEVICE_TABLE(i2c, ac200_ids);
> +
> +static const struct of_device_id ac200_of_match[] = {
> + { .compatible = "x-powers,ac200" },
> + { /* sentinel */ }

No need for this comment.

> +};
> +MODULE_DEVICE_TABLE(of, ac200_of_match);
> +
> +static struct i2c_driver ac200_i2c_driver = {
> + .driver = {
> + .name = "ac200",
> + .of_match_table = of_match_ptr(ac200_of_match),
> + },
> + .probe = ac200_i2c_probe,
> + .remove = ac200_i2c_remove,
> + .id_table = ac200_ids,
> +};
> +module_i2c_driver(ac200_i2c_driver);
> +
> +MODULE_DESCRIPTION("MFD core driver for AC200");

"Parent driver ..."

> +MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@siol.net>");
> +MODULE_LICENSE("GPL v2");
> diff --git a/include/linux/mfd/ac200.h b/include/linux/mfd/ac200.h
> new file mode 100644
> index 000000000000..f75baf0d910c
> --- /dev/null
> +++ b/include/linux/mfd/ac200.h
> @@ -0,0 +1,210 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * AC200 register list
> + *
> + * Copyright (C) 2019 Jernej Skrabec <jernej.skrabec@siol.net>

This usually sits higher.

> + */
> +
> +#ifndef __LINUX_MFD_AC200_H
> +#define __LINUX_MFD_AC200_H
> +
> +#include <linux/clk.h>
> +#include <linux/regmap.h>
> +
> +/* interface registers (can be accessed from any page) */

Please use correct grammar in comments.

"Interface"

> +#define AC200_TWI_CHANGE_TO_RSB 0x3E
> +#define AC200_TWI_PAD_DELAY 0xC4
> +#define AC200_TWI_REG_ADDR_H 0xFE
> +
> +/* General registers */
> +#define AC200_SYS_VERSION 0x0000
> +#define AC200_SYS_CONTROL 0x0002
> +#define AC200_SYS_IRQ_ENABLE 0x0004
> +#define AC200_SYS_IRQ_STATUS 0x0006
> +#define AC200_SYS_CLK_CTL 0x0008
> +#define AC200_SYS_DLDO_OSC_CTL 0x000A
> +#define AC200_SYS_PLL_CTL0 0x000C
> +#define AC200_SYS_PLL_CTL1 0x000E
> +#define AC200_SYS_AUDIO_CTL0 0x0010
> +#define AC200_SYS_AUDIO_CTL1 0x0012
> +#define AC200_SYS_EPHY_CTL0 0x0014
> +#define AC200_SYS_EPHY_CTL1 0x0016
> +#define AC200_SYS_TVE_CTL0 0x0018
> +#define AC200_SYS_TVE_CTL1 0x001A
> +
> +/* Audio Codec registers */
> +#define AC200_AC_SYS_CLK_CTL 0x2000
> +#define AC200_SYS_MOD_RST 0x2002
> +#define AC200_SYS_SAMP_CTL 0x2004
> +#define AC200_I2S_CTL 0x2100
> +#define AC200_I2S_CLK 0x2102
> +#define AC200_I2S_FMT0 0x2104
> +#define AC200_I2S_FMT1 0x2108
> +#define AC200_I2S_MIX_SRC 0x2114
> +#define AC200_I2S_MIX_GAIN 0x2116
> +#define AC200_I2S_DACDAT_DVC 0x2118
> +#define AC200_I2S_ADCDAT_DVC 0x211A
> +#define AC200_AC_DAC_DPC 0x2200
> +#define AC200_AC_DAC_MIX_SRC 0x2202
> +#define AC200_AC_DAC_MIX_GAIN 0x2204
> +#define AC200_DACA_OMIXER_CTRL 0x2220
> +#define AC200_OMIXER_SR 0x2222
> +#define AC200_LINEOUT_CTRL 0x2224
> +#define AC200_AC_ADC_DPC 0x2300
> +#define AC200_MBIAS_CTRL 0x2310
> +#define AC200_ADC_MIC_CTRL 0x2320
> +#define AC200_ADCMIXER_SR 0x2322
> +#define AC200_ANALOG_TUNING0 0x232A
> +#define AC200_ANALOG_TUNING1 0x232C
> +#define AC200_AC_AGC_SEL 0x2480
> +#define AC200_ADC_DAPLCTRL 0x2500
> +#define AC200_ADC_DAPRCTRL 0x2502
> +#define AC200_ADC_DAPLSTA 0x2504
> +#define AC200_ADC_DAPRSTA 0x2506
> +#define AC200_ADC_DAPLTL 0x2508
> +#define AC200_ADC_DAPRTL 0x250A
> +#define AC200_ADC_DAPLHAC 0x250C
> +#define AC200_ADC_DAPLLAC 0x250E
> +#define AC200_ADC_DAPRHAC 0x2510
> +#define AC200_ADC_DAPRLAC 0x2512
> +#define AC200_ADC_DAPLDT 0x2514
> +#define AC200_ADC_DAPLAT 0x2516
> +#define AC200_ADC_DAPRDT 0x2518
> +#define AC200_ADC_DAPRAT 0x251A
> +#define AC200_ADC_DAPNTH 0x251C
> +#define AC200_ADC_DAPLHNAC 0x251E
> +#define AC200_ADC_DAPLLNAC 0x2520
> +#define AC200_ADC_DAPRHNAC 0x2522
> +#define AC200_ADC_DAPRLNAC 0x2524
> +#define AC200_AC_DAPHHPFC 0x2526
> +#define AC200_AC_DAPLHPFC 0x2528
> +#define AC200_AC_DAPOPT 0x252A
> +#define AC200_AC_DAC_DAPCTRL 0x3000
> +#define AC200_AC_DRC_HHPFC 0x3002
> +#define AC200_AC_DRC_LHPFC 0x3004
> +#define AC200_AC_DRC_CTRL 0x3006
> +#define AC200_AC_DRC_LPFHAT 0x3008
> +#define AC200_AC_DRC_LPFLAT 0x300A
> +#define AC200_AC_DRC_RPFHAT 0x300C
> +#define AC200_AC_DRC_RPFLAT 0x300E
> +#define AC200_AC_DRC_LPFHRT 0x3010
> +#define AC200_AC_DRC_LPFLRT 0x3012
> +#define AC200_AC_DRC_RPFHRT 0x3014
> +#define AC200_AC_DRC_RPFLRT 0x3016
> +#define AC200_AC_DRC_LRMSHAT 0x3018
> +#define AC200_AC_DRC_LRMSLAT 0x301A
> +#define AC200_AC_DRC_RRMSHAT 0x301C
> +#define AC200_AC_DRC_RRMSLAT 0x301E
> +#define AC200_AC_DRC_HCT 0x3020
> +#define AC200_AC_DRC_LCT 0x3022
> +#define AC200_AC_DRC_HKC 0x3024
> +#define AC200_AC_DRC_LKC 0x3026
> +#define AC200_AC_DRC_HOPC 0x3028
> +#define AC200_AC_DRC_LOPC 0x302A
> +#define AC200_AC_DRC_HLT 0x302C
> +#define AC200_AC_DRC_LLT 0x302E
> +#define AC200_AC_DRC_HKI 0x3030
> +#define AC200_AC_DRC_LKI 0x3032
> +#define AC200_AC_DRC_HOPL 0x3034
> +#define AC200_AC_DRC_LOPL 0x3036
> +#define AC200_AC_DRC_HET 0x3038
> +#define AC200_AC_DRC_LET 0x303A
> +#define AC200_AC_DRC_HKE 0x303C
> +#define AC200_AC_DRC_LKE 0x303E
> +#define AC200_AC_DRC_HOPE 0x3040
> +#define AC200_AC_DRC_LOPE 0x3042
> +#define AC200_AC_DRC_HKN 0x3044
> +#define AC200_AC_DRC_LKN 0x3046
> +#define AC200_AC_DRC_SFHAT 0x3048
> +#define AC200_AC_DRC_SFLAT 0x304A
> +#define AC200_AC_DRC_SFHRT 0x304C
> +#define AC200_AC_DRC_SFLRT 0x304E
> +#define AC200_AC_DRC_MXGHS 0x3050
> +#define AC200_AC_DRC_MXGLS 0x3052
> +#define AC200_AC_DRC_MNGHS 0x3054
> +#define AC200_AC_DRC_MNGLS 0x3056
> +#define AC200_AC_DRC_EPSHC 0x3058
> +#define AC200_AC_DRC_EPSLC 0x305A
> +#define AC200_AC_DRC_HPFHGAIN 0x305E
> +#define AC200_AC_DRC_HPFLGAIN 0x3060
> +#define AC200_AC_DRC_BISTCR 0x3100
> +#define AC200_AC_DRC_BISTST 0x3102
> +
> +/* TVE registers */
> +#define AC200_TVE_CTL0 0x4000
> +#define AC200_TVE_CTL1 0x4002
> +#define AC200_TVE_MOD0 0x4004
> +#define AC200_TVE_MOD1 0x4006
> +#define AC200_TVE_DAC_CFG0 0x4008
> +#define AC200_TVE_DAC_CFG1 0x400A
> +#define AC200_TVE_YC_DELAY 0x400C
> +#define AC200_TVE_YC_FILTER 0x400E
> +#define AC200_TVE_BURST_FRQ0 0x4010
> +#define AC200_TVE_BURST_FRQ1 0x4012
> +#define AC200_TVE_FRONT_PORCH 0x4014
> +#define AC200_TVE_BACK_PORCH 0x4016
> +#define AC200_TVE_TOTAL_LINE 0x401C
> +#define AC200_TVE_FIRST_ACTIVE 0x401E
> +#define AC200_TVE_BLACK_LEVEL 0x4020
> +#define AC200_TVE_BLANK_LEVEL 0x4022
> +#define AC200_TVE_PLUG_EN 0x4030
> +#define AC200_TVE_PLUG_IRQ_EN 0x4032
> +#define AC200_TVE_PLUG_IRQ_STA 0x4034
> +#define AC200_TVE_PLUG_STA 0x4038
> +#define AC200_TVE_PLUG_DEBOUNCE 0x4040
> +#define AC200_TVE_DAC_TEST 0x4042
> +#define AC200_TVE_PLUG_PULSE_LEVEL 0x40F4
> +#define AC200_TVE_PLUG_PULSE_START 0x40F8
> +#define AC200_TVE_PLUG_PULSE_PERIOD 0x40FA
> +#define AC200_TVE_IF_CTL 0x5000
> +#define AC200_TVE_IF_TIM0 0x5008
> +#define AC200_TVE_IF_TIM1 0x500A
> +#define AC200_TVE_IF_TIM2 0x500C
> +#define AC200_TVE_IF_TIM3 0x500E
> +#define AC200_TVE_IF_SYNC0 0x5010
> +#define AC200_TVE_IF_SYNC1 0x5012
> +#define AC200_TVE_IF_SYNC2 0x5014
> +#define AC200_TVE_IF_TIM4 0x5016
> +#define AC200_TVE_IF_STATUS 0x5018
> +
> +/* EPHY registers */
> +#define AC200_EPHY_CTL 0x6000
> +#define AC200_EPHY_BIST 0x6002
> +
> +/* eFuse registers (0x8000 - 0x9FFF, layout unknown) */
> +
> +/* RTC registers */
> +#define AC200_LOSC_CTRL0 0xA000
> +#define AC200_LOSC_CTRL1 0xA002
> +#define AC200_LOSC_AUTO_SWT_STA 0xA004
> +#define AC200_INTOSC_CLK_PRESCAL 0xA008
> +#define AC200_RTC_YY_MM_DD0 0xA010
> +#define AC200_RTC_YY_MM_DD1 0xA012
> +#define AC200_RTC_HH_MM_SS0 0xA014
> +#define AC200_RTC_HH_MM_SS1 0xA016
> +#define AC200_ALARM0_CUR_VLU0 0xA024
> +#define AC200_ALARM0_CUR_VLU1 0xA026
> +#define AC200_ALARM0_ENABLE 0xA028
> +#define AC200_ALARM0_IRQ_EN 0xA02C
> +#define AC200_ALARM0_IRQ_STA 0xA030
> +#define AC200_ALARM1_WK_HH_MM_SS0 0xA040
> +#define AC200_ALARM1_WK_HH_MM_SS1 0xA042
> +#define AC200_ALARM1_ENABLE 0xA044
> +#define AC200_ALARM1_IRQ_EN 0xA048
> +#define AC200_ALARM1_IRQ_STA 0xA04C
> +#define AC200_ALARM_CONFIG 0xA050
> +#define AC200_LOSC_OUT_GATING 0xA060
> +#define AC200_GP_DATA(x) (0xA100 + (x) * 2)
> +#define AC200_RTC_DEB 0xA170
> +#define AC200_GPL_HOLD_OUTPUT 0xA180
> +#define AC200_VDD_RTC 0xA190
> +#define AC200_IC_CHARA0 0xA1F0
> +#define AC200_IC_CHARA1 0xA1F2
> +
> +struct ac200_dev {
> + struct clk *clk;
> + struct regmap *regmap;
> + struct regmap_irq_chip_data *regmap_irqc;
> +};
> +
> +#endif /* __LINUX_MFD_AC200_H */

--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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