[PATCH linux v1 2/2] drivers: hwmon: hwmon driver for ASPEED AST2400/2500 PWM and Fan tach controller

Guenter Roeck linux at roeck-us.net
Mon Jan 16 06:11:10 AEDT 2017


On 01/09/2017 01:59 PM, Jaghathiswari Rankappagounder Natarajan wrote:
> The ASPEED AST2400/2500 PWM controller supports 8 PWM output ports.
> The ASPEED AST2400/2500 Fan tach controller supports 16 tachometer inputs.
> PWM clock types M, N and 0 are three types just to have three independent PWM
> sources.
> The device driver matches on the device tree node. The configuration values
> are read from the device tree and written to the respective registers.
> The driver provides a sysfs entries through which the user can
> configure the duty-cycle value (ranging from 0 to 100 percent) and read the
> fan tach rpm value.
>
> Signed-off-by: Jaghathiswari Rankappagounder Natarajan <jaghu at google.com>
> ---
>  Documentation/hwmon/aspeed-pwm-tacho |  22 +
>  drivers/hwmon/Kconfig                |   9 +
>  drivers/hwmon/Makefile               |   1 +
>  drivers/hwmon/aspeed-pwm-tacho.c     | 884 +++++++++++++++++++++++++++++++++++
>  4 files changed, 916 insertions(+)
>  create mode 100644 Documentation/hwmon/aspeed-pwm-tacho
>  create mode 100644 drivers/hwmon/aspeed-pwm-tacho.c
>
> diff --git a/Documentation/hwmon/aspeed-pwm-tacho b/Documentation/hwmon/aspeed-pwm-tacho
> new file mode 100644
> index 000000000000..0e9ec6d5f900
> --- /dev/null
> +++ b/Documentation/hwmon/aspeed-pwm-tacho
> @@ -0,0 +1,22 @@
> +Kernel driver aspeed-pwm-tacho
> +==============================
> +
> +Supported chips:
> +	ASPEED AST2400/2500
> +
> +Authors:
> +	<jaghu at google.com>
> +
> +Description:
> +------------
> +This driver implements support for ASPEED AST2400/2500 PWM and Fan Tacho
> +controller. The PWM controller supports upto 8 PWM outputs. The Fan tacho
> +controller supports upto 16 tachometer inputs.
> +
> +The driver provides the following sensor accesses in sysfs:
> +
> +fanX_input	ro	provide current fan rotation value in RPM as reported
> +			by the fan to the device.
> +
> +pwmX		rw	get or set PWM fan control value. This is an integer
> +			value between 0(off) and 255(full speed).
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 45cef3d2c75c..757b5b0705bf 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -341,6 +341,15 @@ config SENSORS_ASB100
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called asb100.
>
> +config SENSORS_ASPEED
> +	tristate "ASPEED AST2400/AST2500 PWM and Fan tach driver"
> +	help
> +	  This driver provides support for ASPEED AST2400/AST2500 PWM
> +	  and Fan Tacho controllers.
> +
> +	  This driver can also be built as a module. If so, the module
> +	  will be called aspeed_pwm_tacho.
> +
>  config SENSORS_ATXP1
>  	tristate "Attansic ATXP1 VID controller"
>  	depends on I2C
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index aecf4ba17460..83025cc9bb45 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -46,6 +46,7 @@ obj-$(CONFIG_SENSORS_ADT7475)	+= adt7475.o
>  obj-$(CONFIG_SENSORS_APPLESMC)	+= applesmc.o
>  obj-$(CONFIG_SENSORS_ARM_SCPI)	+= scpi-hwmon.o
>  obj-$(CONFIG_SENSORS_ASC7621)	+= asc7621.o
> +obj-$(CONFIG_SENSORS_ASPEED)	+= aspeed-pwm-tacho.o
>  obj-$(CONFIG_SENSORS_ATXP1)	+= atxp1.o
>  obj-$(CONFIG_SENSORS_CORETEMP)	+= coretemp.o
>  obj-$(CONFIG_SENSORS_DA9052_ADC)+= da9052-hwmon.o
> diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c
> new file mode 100644
> index 000000000000..93eb3be2e506
> --- /dev/null
> +++ b/drivers/hwmon/aspeed-pwm-tacho.c
> @@ -0,0 +1,884 @@
> +/*
> + * Copyright (c) 2016 Google, Inc
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 or later as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/delay.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/sysfs.h>
> +
> +/* ASPEED PWM & FAN Tach Register Definition */
> +#define ASPEED_PTCR_CTRL		0x00
> +#define ASPEED_PTCR_CLK_CTRL		0x04
> +#define ASPEED_PTCR_DUTY0_CTRL		0x08
> +#define ASPEED_PTCR_DUTY1_CTRL		0x0c
> +#define ASPEED_PTCR_TYPEM_CTRL		0x10
> +#define ASPEED_PTCR_TYPEM_CTRL1		0x14
> +#define ASPEED_PTCR_TYPEN_CTRL		0x18
> +#define ASPEED_PTCR_TYPEN_CTRL1		0x1c
> +#define ASPEED_PTCR_TACH_SOURCE		0x20
> +#define ASPEED_PTCR_TRIGGER		0x28
> +#define ASPEED_PTCR_RESULT		0x2c
> +#define ASPEED_PTCR_INTR_CTRL		0x30
> +#define ASPEED_PTCR_INTR_STS		0x34
> +#define ASPEED_PTCR_TYPEM_LIMIT		0x38
> +#define ASPEED_PTCR_TYPEN_LIMIT		0x3C
> +#define ASPEED_PTCR_CTRL_EXT		0x40
> +#define ASPEED_PTCR_CLK_CTRL_EXT	0x44
> +#define ASPEED_PTCR_DUTY2_CTRL		0x48
> +#define ASPEED_PTCR_DUTY3_CTRL		0x4c
> +#define ASPEED_PTCR_TYPEO_CTRL		0x50
> +#define ASPEED_PTCR_TYPEO_CTRL1		0x54
> +#define ASPEED_PTCR_TACH_SOURCE_EXT	0x60
> +#define ASPEED_PTCR_TYPEO_LIMIT		0x78
> +
> +/* ASPEED_PTCR_CTRL : 0x00 - General Control Register */
> +#define ASPEED_PTCR_CTRL_SET_PWMD_TYPE_PART1	15
> +#define ASPEED_PTCR_CTRL_SET_PWMD_TYPE_PART2	6
> +#define ASPEED_PTCR_CTRL_SET_PWMD_TYPE_MASK	(BIT(7) | BIT(15))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWMC_TYPE_PART1	14
> +#define ASPEED_PTCR_CTRL_SET_PWMC_TYPE_PART2	5
> +#define ASPEED_PTCR_CTRL_SET_PWMC_TYPE_MASK	(BIT(6) | BIT(14))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWMB_TYPE_PART1	13
> +#define ASPEED_PTCR_CTRL_SET_PWMB_TYPE_PART2	4
> +#define ASPEED_PTCR_CTRL_SET_PWMB_TYPE_MASK	(BIT(5) | BIT(13))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWMA_TYPE_PART1	12
> +#define ASPEED_PTCR_CTRL_SET_PWMA_TYPE_PART2	3
> +#define ASPEED_PTCR_CTRL_SET_PWMA_TYPE_MASK	(BIT(4) | BIT(12))
> +
> +#define	ASPEED_PTCR_CTRL_FAN_NUM_EN(x)	(0x1 << (16 + (x)))
> +
> +#define	ASPEED_PTCR_CTRL_PWMD_EN	(0x1 << 11)
> +#define	ASPEED_PTCR_CTRL_PWMC_EN	(0x1 << 10)
> +#define	ASPEED_PTCR_CTRL_PWMB_EN	(0x1 << 9)
> +#define	ASPEED_PTCR_CTRL_PWMA_EN	(0x1 << 8)
> +
Why not BIT() ?

> +#define	ASPEED_PTCR_CTRL_CLK_SRC	0x2
> +#define	ASPEED_PTCR_CTRL_CLK_EN		0x1

BIT(0) and BIT(1) ?

> +
> +/* ASPEED_PTCR_CLK_CTRL : 0x04 - Clock Control Register */
> +/* TYPE N */
> +#define ASPEED_PTCR_CLK_CTRL_TYPEN_UNIT		24
> +#define ASPEED_PTCR_CLK_CTRL_TYPEN_H		20
> +#define ASPEED_PTCR_CLK_CTRL_TYPEN_L		16
> +/* TYPE M */
> +#define ASPEED_PTCR_CLK_CTRL_TYPEM_UNIT		8
> +#define ASPEED_PTCR_CLK_CTRL_TYPEM_H		4
> +#define ASPEED_PTCR_CLK_CTRL_TYPEM_L		0
> +
> +/*
> + * ASPEED_PTCR_DUTY_CTRL/1/2/3 : 0x08/0x0C/0x48/0x4C - PWM-FAN duty control
> + * 0/1/2/3 register
> + */
> +#define DUTY_CTRL_PWM2_FALL_POINT	24
> +#define DUTY_CTRL_PWM2_RISE_POINT	16
> +#define DUTY_CTRL_PWM1_FALL_POINT	8
> +#define DUTY_CTRL_PWM1_RISE_POINT	0
> +
> +/* ASPEED_PTCR_TYPEM_CTRL : 0x10/0x18/0x50 - Type M/N/O Ctrl 0 Register */
> +#define TYPE_CTRL_FAN_PERIOD		16
> +#define TYPE_CTRL_FAN_MODE		4
> +#define TYPE_CTRL_FAN_DIVISION		1
> +#define TYPE_CTRL_FAN_TYPE_EN		1
> +
> +/* ASPEED_PTCR_TACH_SOURCE : 0x20/0x60 - Tach Source Register */
> +/* bit [0,1] at 0x20, bit [2] at 0x60 */
> +#define TACH_PWM_SOURCE_BIT01(x)	((x) * 2)
> +#define TACH_PWM_SOURCE_BIT2(x)		((x) * 2)
> +#define TACH_PWM_SOURCE_MASK_BIT01(x)	(0x3 << ((x) * 2))
> +#define TACH_PWM_SOURCE_MASK_BIT2(x)	(0x1 << ((x) * 2))
> +
> +/* ASPEED_PTCR_TRIGGER : 0x28 - Trigger Register */
> +#define TRIGGER_READ_FAN_NUM(x)		(0x1 << (x))

Why not BIT() ?

> +
> +/* ASPEED_PTCR_RESULT : 0x2c - Result Register */
> +#define RESULT_STATUS			31
> +#define RESULT_VALUE_MASK		0xfffff
> +
> +/* ASPEED_PTCR_CTRL_EXT : 0x40 - General Control Extension #1 Register */
> +#define ASPEED_PTCR_CTRL_SET_PWMH_TYPE_PART1	15
> +#define ASPEED_PTCR_CTRL_SET_PWMH_TYPE_PART2	6
> +#define ASPEED_PTCR_CTRL_SET_PWMH_TYPE_MASK	(BIT(7) | BIT(15))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWMG_TYPE_PART1	14
> +#define ASPEED_PTCR_CTRL_SET_PWMG_TYPE_PART2	5
> +#define ASPEED_PTCR_CTRL_SET_PWMG_TYPE_MASK	(BIT(6) | BIT(14))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWMF_TYPE_PART1	13
> +#define ASPEED_PTCR_CTRL_SET_PWMF_TYPE_PART2	4
> +#define ASPEED_PTCR_CTRL_SET_PWMF_TYPE_MASK	(BIT(5) | BIT(13))
> +
> +#define ASPEED_PTCR_CTRL_SET_PWME_TYPE_PART1	12
> +#define ASPEED_PTCR_CTRL_SET_PWME_TYPE_PART2	3
> +#define ASPEED_PTCR_CTRL_SET_PWME_TYPE_MASK	(BIT(4) | BIT(12))
> +
> +#define	ASPEED_PTCR_CTRL_PWMH_EN	(0x1 << 11)
> +#define	ASPEED_PTCR_CTRL_PWMG_EN	(0x1 << 10)
> +#define	ASPEED_PTCR_CTRL_PWMF_EN	(0x1 << 9)
> +#define	ASPEED_PTCR_CTRL_PWME_EN	(0x1 << 8)

Why not BIT() ?

> +
> +/* ASPEED_PTCR_CLK_EXT_CTRL : 0x44 - Clock Control Extension #1 Register */
> +/* TYPE O */
> +#define ASPEED_PTCR_CLK_CTRL_TYPEO_UNIT		8
> +#define ASPEED_PTCR_CLK_CTRL_TYPEO_H		4
> +#define ASPEED_PTCR_CLK_CTRL_TYPEO_L		0
> +
> +#define MCLK 1
> +#define PWM_MAX 255
> +#define MAX_HIGH_LOW_BIT 15
> +
> +struct aspeed_pwm_tacho_data {
> +	void __iomem *base;
> +	unsigned long clk_freq;
> +	const struct attribute_group *groups[24];
> +	u8 type_pwm_clock_unit[3];
> +	u8 type_pwm_clock_division_h[3];
> +	u8 type_pwm_clock_division_l[3];
> +	u8 type_fan_tach_clock_division[3];
> +	u16 type_fan_tach_unit[3];
> +	u8 pwm_port_type[8];
> +	u8 pwm_port_fan_ctrl[8];
> +	u8 fan_tach_ch_source[16];
> +};
> +
> +enum type { TYPEM, TYPEN, TYPEO };
> +
> +struct type_params {
> +	u32 l_value;
> +	u32 h_value;
> +	u32 unit_value;
> +	u32 clk_ctrl_reg;
> +	u32 ctrl_reg;
> +	u32 ctrl_reg1;
> +};
> +
> +static const struct type_params type_params[] = {
> +	[TYPEM] = {
> +		.l_value = ASPEED_PTCR_CLK_CTRL_TYPEM_L,
> +		.h_value = ASPEED_PTCR_CLK_CTRL_TYPEM_H,
> +		.unit_value = ASPEED_PTCR_CLK_CTRL_TYPEM_UNIT,
> +		.clk_ctrl_reg = ASPEED_PTCR_CLK_CTRL,
> +		.ctrl_reg = ASPEED_PTCR_TYPEM_CTRL,
> +		.ctrl_reg1 = ASPEED_PTCR_TYPEM_CTRL1,
> +	},
> +	[TYPEN] = {
> +		.l_value = ASPEED_PTCR_CLK_CTRL_TYPEN_L,
> +		.h_value = ASPEED_PTCR_CLK_CTRL_TYPEN_H,
> +		.unit_value = ASPEED_PTCR_CLK_CTRL_TYPEN_UNIT,
> +		.clk_ctrl_reg = ASPEED_PTCR_CLK_CTRL,
> +		.ctrl_reg = ASPEED_PTCR_TYPEN_CTRL,
> +		.ctrl_reg1 = ASPEED_PTCR_TYPEN_CTRL1,
> +	},
> +	[TYPEO] = {
> +		.l_value = ASPEED_PTCR_CLK_CTRL_TYPEO_L,
> +		.h_value = ASPEED_PTCR_CLK_CTRL_TYPEO_H,
> +		.unit_value = ASPEED_PTCR_CLK_CTRL_TYPEO_UNIT,
> +		.clk_ctrl_reg = ASPEED_PTCR_CLK_CTRL_EXT,
> +		.ctrl_reg = ASPEED_PTCR_TYPEO_CTRL,
> +		.ctrl_reg1 = ASPEED_PTCR_TYPEO_CTRL1,
> +	}
> +};
> +
> +enum pwm_port { PWMA, PWMB, PWMC, PWMD, PWME, PWMF, PWMG, PWMH };
> +
> +struct pwm_port_params {
> +	u32 pwm_en;
> +	u32 ctrl_reg;
> +	u32 type_part1;
> +	u32 type_part2;
> +	u32 type_mask;
> +	u32 duty_ctrl_rise_point;
> +	u32 duty_ctrl_fall_point;
> +	u32 duty_ctrl_reg;
> +	u8 duty_ctrl_calc_type;
> +};
> +
> +static const struct pwm_port_params pwm_port_params[] = {
> +	[PWMA] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMA_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMA_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMA_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMA_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM1_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM1_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY0_CTRL,
> +		.duty_ctrl_calc_type = 0,
> +	},
> +	[PWMB] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMB_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMB_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMB_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMB_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM2_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM2_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY0_CTRL,
> +		.duty_ctrl_calc_type = 1,
> +	},
> +	[PWMC] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMC_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMC_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMC_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMC_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM1_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM1_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY1_CTRL,
> +		.duty_ctrl_calc_type = 0,
> +	},
> +	[PWMD] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMD_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMD_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMD_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMD_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM2_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM2_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY1_CTRL,
> +		.duty_ctrl_calc_type = 1,
> +	},
> +	[PWME] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWME_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL_EXT,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWME_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWME_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWME_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM1_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM1_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY2_CTRL,
> +		.duty_ctrl_calc_type = 0,
> +	},
> +	[PWMF] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMF_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL_EXT,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMF_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMF_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMF_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM2_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM2_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY2_CTRL,
> +		.duty_ctrl_calc_type = 1,
> +	},
> +	[PWMG] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMG_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL_EXT,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMG_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMG_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMG_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM1_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM1_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY3_CTRL,
> +		.duty_ctrl_calc_type = 0,
> +	},
> +	[PWMH] = {
> +		.pwm_en = ASPEED_PTCR_CTRL_PWMH_EN,
> +		.ctrl_reg = ASPEED_PTCR_CTRL_EXT,
> +		.type_part1 = ASPEED_PTCR_CTRL_SET_PWMH_TYPE_PART1,
> +		.type_part2 = ASPEED_PTCR_CTRL_SET_PWMH_TYPE_PART2,
> +		.type_mask = ASPEED_PTCR_CTRL_SET_PWMH_TYPE_MASK,
> +		.duty_ctrl_rise_point = DUTY_CTRL_PWM2_RISE_POINT,
> +		.duty_ctrl_fall_point = DUTY_CTRL_PWM2_FALL_POINT,
> +		.duty_ctrl_reg = ASPEED_PTCR_DUTY3_CTRL,
> +		.duty_ctrl_calc_type = 1,
> +	}
> +};
> +
> +static void aspeed_set_clock_enable(void __iomem *base, bool val)
> +{
> +	u32 reg_value = ioread32(base + ASPEED_PTCR_CTRL);
> +
> +	if (val)
> +		reg_value |= ASPEED_PTCR_CTRL_CLK_EN;
> +	else
> +		reg_value &= ~ASPEED_PTCR_CTRL_CLK_EN;
> +
> +	iowrite32(reg_value, base + ASPEED_PTCR_CTRL);

Those functions make me wonder if it would make sense to use regmap.

> +}
> +
> +static void aspeed_set_clock_source(void __iomem *base, int val)
> +{
> +	u32 reg_value = ioread32(base + ASPEED_PTCR_CTRL);
> +
> +	if (val == MCLK)
> +		reg_value |= ASPEED_PTCR_CTRL_CLK_SRC;
> +	else
> +		reg_value &= ~ASPEED_PTCR_CTRL_CLK_SRC;
> +
> +	iowrite32(reg_value, base + ASPEED_PTCR_CTRL);
> +}
> +
> +static void aspeed_set_pwm_clock_values(void __iomem *base, u8 type,
> +					u8 div_high, u8 div_low, u8 unit)
> +{
> +	u32 reg_offset = type_params[type].clk_ctrl_reg;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	reg_value &= ~((0xF << type_params[type].h_value) |
> +	(0xF << type_params[type].l_value) |
> +	(0xFF << type_params[type].unit_value));
> +	reg_value |= ((div_high << type_params[type].h_value) |
> +	(div_low << type_params[type].l_value) |
> +	(unit << type_params[type].unit_value));
> +
> +	iowrite32(reg_value, base + reg_offset);
> +}
> +
> +static void aspeed_set_pwm_port_enable(void __iomem *base, u8 pwm_port,
> +				       bool enable)
> +{
> +	u32 reg_offset = pwm_port_params[pwm_port].ctrl_reg;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	if (enable)
> +		reg_value |= pwm_port_params[pwm_port].pwm_en;
> +	else
> +		reg_value &= ~pwm_port_params[pwm_port].pwm_en;
> +	iowrite32(reg_value, base + reg_offset);
> +}
> +
> +static void aspeed_set_pwm_port_type(void __iomem *base, u8 pwm_port, u8 type)
> +{
> +	u32 reg_offset = pwm_port_params[pwm_port].ctrl_reg;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	reg_value &= ~pwm_port_params[pwm_port].type_mask;
> +	reg_value |= (type & 0x1) <<
> +		pwm_port_params[pwm_port].type_part1;
> +	reg_value |= (type & 0x2) <<
> +		pwm_port_params[pwm_port].type_part2;
> +
> +	iowrite32(reg_value, base + reg_offset);
> +}
> +
> +static void aspeed_set_pwm_port_duty_rising_falling(void __iomem *base,
> +						    u8 pwm_port, u8 rising,
> +						    u8 falling)
> +{
> +	u32 reg_offset = pwm_port_params[pwm_port].duty_ctrl_reg;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	reg_value &= ~(0xFF << pwm_port_params[pwm_port].duty_ctrl_rise_point);
> +	reg_value &= ~(0xFF << pwm_port_params[pwm_port].duty_ctrl_fall_point);
> +
> +	if (pwm_port_params[pwm_port].duty_ctrl_calc_type == 0) {
> +		reg_value |= rising;
> +	} else if (pwm_port_params[pwm_port].duty_ctrl_calc_type == 1) {
> +		reg_value |= (rising <<
> +			pwm_port_params[pwm_port].duty_ctrl_rise_point);
> +	}
> +	reg_value |= (falling <<
> +			pwm_port_params[pwm_port].duty_ctrl_fall_point);
> +
> +	iowrite32(reg_value, base + reg_offset);
> +}
> +
> +static void aspeed_set_tacho_type_enable(void __iomem *base, u8 type,
> +					 bool enable)
> +{
> +	u32 reg_offset = type_params[type].ctrl_reg;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	if (enable)
> +		reg_value |= TYPE_CTRL_FAN_TYPE_EN;
> +	else
> +		reg_value &= ~TYPE_CTRL_FAN_TYPE_EN;
> +
> +	iowrite32(reg_value, base + reg_offset);
> +}
> +
> +static void aspeed_set_tacho_type_values(void __iomem *base, u8 type, u8 mode,
> +					 u16 unit, u8 division)
> +{
> +	u32 reg_offset = type_params[type].ctrl_reg;
> +	u32 reg_offset1 = type_params[type].ctrl_reg1;
> +	u32 reg_value = ioread32(base + reg_offset);
> +
> +	reg_value &= ~((0x3 << TYPE_CTRL_FAN_MODE) |
> +			(0xFFFF << TYPE_CTRL_FAN_PERIOD) |
> +			(0x7 << TYPE_CTRL_FAN_DIVISION));
> +	reg_value |= ((mode << TYPE_CTRL_FAN_MODE) |
> +			(unit << TYPE_CTRL_FAN_PERIOD) |
> +			(division << TYPE_CTRL_FAN_DIVISION));
> +
> +	iowrite32(reg_value, base + reg_offset);
> +
> +	iowrite32(unit << 16, base + reg_offset1);
> +}
> +
> +static void aspeed_set_fan_tach_ch_enable(void __iomem *base, u8 fan_tach_ch,
> +					  bool enable)
> +{
> +	u32 reg_value = ioread32(base + ASPEED_PTCR_CTRL);
> +
> +	if (enable)
> +		reg_value |= ASPEED_PTCR_CTRL_FAN_NUM_EN(fan_tach_ch);
> +	else
> +		reg_value &= ~ASPEED_PTCR_CTRL_FAN_NUM_EN(fan_tach_ch);
> +
> +	iowrite32(reg_value, base + ASPEED_PTCR_CTRL);
> +}
> +
> +static void aspeed_set_fan_tach_ch_source(void __iomem *base, u8 fan_tach_ch,
> +					  u8 fan_tach_ch_source)
> +{
> +	u32 reg_value1 = ioread32(base + ASPEED_PTCR_TACH_SOURCE);
> +	u32 reg_value2 = ioread32(base + ASPEED_PTCR_TACH_SOURCE_EXT);
> +
> +	reg_value1 &= ~(TACH_PWM_SOURCE_MASK_BIT01(fan_tach_ch));
> +	reg_value1 |= ((fan_tach_ch_source & 0x3) <<
> +			(TACH_PWM_SOURCE_BIT01(fan_tach_ch)));
> +
> +	reg_value2 &= ~(TACH_PWM_SOURCE_MASK_BIT2(fan_tach_ch));
> +	reg_value2 |= (((fan_tach_ch_source & 0x4) >> 2) <<
> +			(TACH_PWM_SOURCE_BIT2(fan_tach_ch)));
> +
> +	iowrite32(reg_value1, base + ASPEED_PTCR_TACH_SOURCE);
> +	iowrite32(reg_value2, base + ASPEED_PTCR_TACH_SOURCE_EXT);
> +}
> +
> +static void aspeed_set_pwm_port_fan_ctrl(struct aspeed_pwm_tacho_data *priv,
> +					 u8 index, u8 fan_ctrl)
> +{
> +	u16 period;
> +	u16 dc_time_on;
> +
> +	period = priv->type_pwm_clock_unit[priv->pwm_port_type[index]];
> +	period += 1;
> +	dc_time_on = (fan_ctrl * period) / PWM_MAX;
> +
> +	if (dc_time_on == 0) {
> +		aspeed_set_pwm_port_enable(priv->base, index, false);
> +	} else {
> +		if (dc_time_on == period)
> +			dc_time_on = 0;
> +
> +		aspeed_set_pwm_port_duty_rising_falling(priv->base, index, 0,
> +							dc_time_on);
> +		aspeed_set_pwm_port_enable(priv->base, index, true);
> +	}
> +}
> +
> +static u32 aspeed_get_fan_tach_ch_measure_period(struct aspeed_pwm_tacho_data
> +						 *priv, u8 type)
> +{
> +	u32 clk;
> +	u16 tacho_unit;
> +	u8 clk_unit, div_h, div_l, tacho_div;
> +
> +	clk = priv->clk_freq;
> +
> +	clk_unit = priv->type_pwm_clock_unit[type];
> +	div_h = priv->type_pwm_clock_division_h[type];
> +	div_h = 0x1 << div_h;
> +	div_l = priv->type_pwm_clock_division_l[type];
> +	if (div_l == 0)
> +		div_l = 1;
> +	else
> +		div_l = div_l * 2;
> +
> +	tacho_unit = priv->type_fan_tach_unit[type];
> +	tacho_div = priv->type_fan_tach_clock_division[type];
> +
> +	tacho_div = 0x4 << (tacho_div * 2);
> +	return clk / (clk_unit * div_h * div_l * tacho_div * tacho_unit);
> +}
> +
> +static u32 aspeed_get_fan_tach_ch_rpm(struct aspeed_pwm_tacho_data *priv,
> +				      u8 fan_tach_ch)
> +{
> +	u32 raw_data, rpm, tach_div, clk_source, timeout = 0, sec;
> +	u8 fan_tach_ch_source, type;
> +	void __iomem *base = priv->base;
> +
> +	iowrite32(0, priv->base + ASPEED_PTCR_TRIGGER);
> +	iowrite32(0x1 << fan_tach_ch, priv->base + ASPEED_PTCR_TRIGGER);
> +
> +	fan_tach_ch_source = priv->fan_tach_ch_source[fan_tach_ch];
> +	type = priv->pwm_port_type[fan_tach_ch_source];
> +
> +	sec = (1000 / aspeed_get_fan_tach_ch_measure_period(priv, type));
> +
> +	msleep(sec);
> +
> +	while (!(ioread32(priv->base + ASPEED_PTCR_RESULT) &
> +				(0x1 << RESULT_STATUS))) {
> +		timeout++;
> +		if (timeout > 1)
> +			return 0;
> +		msleep(sec);
> +	};
> +
> +	raw_data = (ioread32(base + ASPEED_PTCR_RESULT)) &
> +				RESULT_VALUE_MASK;
> +	tach_div = priv->type_fan_tach_clock_division[type];
> +
> +	tach_div = 0x4 << (tach_div * 2);
> +	clk_source = priv->clk_freq;
> +	rpm = (clk_source * 60) / (2 * raw_data * tach_div);

Can raw_data be 0 ?

> +	return rpm;
> +}
> +
> +static ssize_t set_pwm(struct device *dev, struct device_attribute *attr,
> +		       const char *buf, size_t count)
> +{
> +	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
> +	int index = sensor_attr->index;
> +	int ret;
> +
No empty line here, please.

> +	struct aspeed_pwm_tacho_data *priv = dev_get_drvdata(dev);
> +	long fan_ctrl;
> +
> +	ret = kstrtol(buf, 10, &fan_ctrl);
> +	if (ret != 0)
> +		return ret;
> +
> +	if (fan_ctrl < 0 || fan_ctrl > PWM_MAX)
> +		return -EINVAL;
> +
> +	if (priv->pwm_port_fan_ctrl[index] == fan_ctrl)
> +		return count;
> +
> +	priv->pwm_port_fan_ctrl[index] = fan_ctrl;
> +	aspeed_set_pwm_port_fan_ctrl(priv, index, fan_ctrl);
> +
> +	return count;
> +}
> +
> +static ssize_t show_pwm(struct device *dev, struct device_attribute *attr,
> +			char *buf)
> +{
> +	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
> +	int index = sensor_attr->index;
> +
In general, please keep variable declarations together with no empty line in between.

> +	struct aspeed_pwm_tacho_data *priv = dev_get_drvdata(dev);
> +
> +	return sprintf(buf, "%u\n", priv->pwm_port_fan_ctrl[index]);
> +}
> +
> +static ssize_t show_rpm(struct device *dev, struct device_attribute *attr,
> +			char *buf)
> +{
> +	struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
> +	int index = sensor_attr->index;
> +	u32 rpm;
> +
> +	struct aspeed_pwm_tacho_data *priv = dev_get_drvdata(dev);
> +
> +	rpm = aspeed_get_fan_tach_ch_rpm(priv, index);
> +
> +	return sprintf(buf, "%u\n", rpm);
> +}
> +
> +#define pwm_index(index)					\
> +static SENSOR_DEVICE_ATTR(pwm##index, 0644,	\
> +			show_pwm, set_pwm, index - 1);		\
> +								\
> +static struct attribute *pwm##index##_dev_attrs[] = {		\
> +	&sensor_dev_attr_pwm##index.dev_attr.attr,		\
> +	NULL,							\
> +};								\
> +static const struct attribute_group pwm##index##_dev_groups = {	\
> +	.attrs = pwm##index##_dev_attrs,			\
> +}
> +
> +#define fan_index(index)					\
> +static SENSOR_DEVICE_ATTR(fan##index##_input, 0444,		\
> +		show_rpm, NULL, index - 1);			\
> +								\
> +static struct attribute *fan##index##_dev_attrs[] = {		\
> +	&sensor_dev_attr_fan##index##_input.dev_attr.attr,	\
> +	NULL,							\
> +};								\
> +static const struct attribute_group fan##index##_dev_groups = {	\
> +	.attrs = fan##index##_dev_attrs,			\
> +}
> +
> +pwm_index(1);
> +pwm_index(2);
> +pwm_index(3);
> +pwm_index(4);
> +pwm_index(5);
> +pwm_index(6);
> +pwm_index(7);
> +pwm_index(8);
> +
> +fan_index(1);
> +fan_index(2);
> +fan_index(3);
> +fan_index(4);
> +fan_index(5);
> +fan_index(6);
> +fan_index(7);
> +fan_index(8);
> +fan_index(9);
> +fan_index(10);
> +fan_index(11);
> +fan_index(12);
> +fan_index(13);
> +fan_index(14);
> +fan_index(15);
> +fan_index(16);
> +
Please no such macros, and not that many groups. One or at most two groups
(one for pwm, one for fans), then use the is_visible callback to determine
if an attribute is visible.


> +/*
> + * If the clock type is type M then :
> + * The PWM frequency = 24MHz / (type M clock division L bit *
> + * type M clock division H bit * (type M PWM period bit + 1))
> + * Calculate type M clock division L bit and H bits given the other values
> + */
> +static int aspeed_create_type(struct device_node *child,
> +			      struct aspeed_pwm_tacho_data *priv,
> +			      u8 index)
> +{
> +	u8 period, div_l, div_h;
> +	bool enable;
> +	u8 mode, div;
> +	u16 unit;
> +
> +	of_property_read_u8(child, "pwm_period", &period);
> +	of_property_read_u8(child, "pwm_clock_division_h", &div_h);
> +	of_property_read_u8(child, "pwm_clock_division_l", &div_l);

What happens if those properties are undefined ?

> +	priv->type_pwm_clock_division_h[index] = div_h;
> +	priv->type_pwm_clock_division_l[index] = div_l;
> +	priv->type_pwm_clock_unit[index] = period;
> +	aspeed_set_pwm_clock_values(priv->base, index, div_h, div_l, period);
> +
> +	enable = of_property_read_bool(child, "fan_tach_enable");
> +	aspeed_set_tacho_type_enable(priv->base, index, enable);
> +
> +	of_property_read_u8(child, "fan_tach_clock_division", &div);
> +	priv->type_fan_tach_clock_division[index] = div;
> +
> +	of_property_read_u8(child, "fan_tach_mode_selection", &mode);
> +
> +	of_property_read_u16(child, "fan_tach_period", &unit);
> +	priv->type_fan_tach_unit[index] = unit;
> +	aspeed_set_tacho_type_values(priv->base, index, mode, unit, div);
> +
> +	return 0;
> +}
> +
> +static int aspeed_create_pwm_port(struct device_node *child,
> +				  struct aspeed_pwm_tacho_data *priv, u8 index,
> +				  u8 group_index)
> +{
> +	u8 val;
> +	bool enable;
> +
> +	switch (index) {
> +	case 1:
> +		priv->groups[group_index] = &pwm1_dev_groups;
> +		break;
> +	case 2:
> +		priv->groups[group_index] = &pwm2_dev_groups;
> +		break;
> +	case 3:
> +		priv->groups[group_index] = &pwm3_dev_groups;
> +		break;
> +	case 4:
> +		priv->groups[group_index] = &pwm4_dev_groups;
> +		break;
> +	case 5:
> +		priv->groups[group_index] = &pwm5_dev_groups;
> +		break;
> +	case 6:
> +		priv->groups[group_index] = &pwm6_dev_groups;
> +		break;
> +	case 7:
> +		priv->groups[group_index] = &pwm7_dev_groups;
> +		break;
> +	case 8:
> +		priv->groups[group_index] = &pwm8_dev_groups;
> +		break;
> +	}
> +
> +	enable = of_property_read_bool(child, "enable");
> +	aspeed_set_pwm_port_enable(priv->base, index - 1, enable);
> +
This looks wrong. If the child is not enabled in the devicetree,
per standard devicetree convention, we should not get here.

Overall I am a bit guessing here, but it seems that you want consecutive
attributes with no gap. This isn't the way to go, though. The attribute
names associate with a given port should not change if another port is
enabled or disabled. pwmX should always point to a well defined pwm
pin on the chip. So, again, please use one group, and enable the individual
attributes with is_visible.

> +	of_property_read_u8(child, "type", &val);

What happens if this property is undefined ?

> +	priv->pwm_port_type[index - 1] = val;
> +	aspeed_set_pwm_port_type(priv->base, index - 1, val);
> +
> +	of_property_read_u8(child, "fan_ctrl", &val);

and if undefined ?

> +	priv->pwm_port_fan_ctrl[index - 1] = val;
> +	aspeed_set_pwm_port_fan_ctrl(priv, index - 1, val);
> +
> +	return 0;
> +}
> +
> +static int aspeed_create_fan_tach_channel(struct device *dev,
> +					  struct device_node *child,
> +					  struct aspeed_pwm_tacho_data *priv,
> +					  u8 index, u8 group_index)
> +{
> +	u8 val;
> +	bool enable;
> +	struct gpio_desc *fan_ctrl = devm_gpiod_get(dev, "fan-ctrl", GPIOD_IN);
> +
> +	if (IS_ERR(fan_ctrl))
> +		return PTR_ERR(fan_ctrl);
> +
> +	switch (index) {
> +	case 1:
> +		priv->groups[group_index] = &fan1_dev_groups;
> +		break;
> +	case 2:
> +		priv->groups[group_index] = &fan2_dev_groups;
> +		break;
> +	case 3:
> +		priv->groups[group_index] = &fan3_dev_groups;
> +		break;
> +	case 4:
> +		priv->groups[group_index] = &fan4_dev_groups;
> +		break;
> +	case 5:
> +		priv->groups[group_index] = &fan5_dev_groups;
> +		break;
> +	case 6:
> +		priv->groups[group_index] = &fan6_dev_groups;
> +		break;
> +	case 7:
> +		priv->groups[group_index] = &fan7_dev_groups;
> +		break;
> +	case 8:
> +		priv->groups[group_index] = &fan8_dev_groups;
> +		break;
> +	case 9:
> +		priv->groups[group_index] = &fan9_dev_groups;
> +		break;
> +	case 10:
> +		priv->groups[group_index] = &fan10_dev_groups;
> +		break;
> +	case 11:
> +		priv->groups[group_index] = &fan11_dev_groups;
> +		break;
> +	case 12:
> +		priv->groups[group_index] = &fan12_dev_groups;
> +		break;
> +	case 13:
> +		priv->groups[group_index] = &fan13_dev_groups;
> +		break;
> +	case 14:
> +		priv->groups[group_index] = &fan14_dev_groups;
> +		break;
> +	case 15:
> +		priv->groups[group_index] = &fan15_dev_groups;
> +		break;
> +	case 16:
> +		priv->groups[group_index] = &fan16_dev_groups;
> +		break;
> +	}
> +
> +	enable = of_property_read_bool(child, "enable");
> +	aspeed_set_fan_tach_ch_enable(priv->base, index - 1, enable);
> +
> +	of_property_read_u8(child, "pwm_source", &val);

if undefined ?

> +	priv->fan_tach_ch_source[index - 1] = val;
> +	aspeed_set_fan_tach_ch_source(priv->base, index - 1, val);
> +
> +	return 0;
> +}
> +
> +static int aspeed_pwm_tacho_probe(struct platform_device *pdev)
> +{
	struct device *dev = &pdev->dev;

might make the rest of the code easier to read.

> +	struct device_node *np, *type_np, *pwm_np, *fan_tach_np, *child;
> +	u8 pwm_index = 1, fan_index = 1, type_index = 0, group_index = 0;
> +	struct aspeed_pwm_tacho_data *priv;
> +	struct resource *res;
> +	struct device *hwmon;
> +	void __iomem *base;
> +	struct clk *clk;
> +
> +	np = pdev->dev.of_node;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res)
> +		return -ENOENT;
> +
> +	base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
> +	if (!base)
> +		return -ENOMEM;
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +	priv->base = base;
> +
> +	iowrite32(0, base + ASPEED_PTCR_TACH_SOURCE);
> +	iowrite32(0, base + ASPEED_PTCR_TACH_SOURCE_EXT);
> +
> +	clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(clk))
> +		return -ENODEV;
> +
> +	priv->clk_freq = clk_get_rate(clk);
> +	aspeed_set_clock_enable(base, true);
> +	aspeed_set_clock_source(base, 0);
> +
> +	type_np = of_get_child_by_name(np, "type_values");
> +	for_each_child_of_node(type_np, child) {
> +		aspeed_create_type(child, priv, type_index++);
> +		of_node_put(child);

Wrong.

> +	}
> +	of_node_put(type_np);
> +	pwm_np = of_get_child_by_name(np, "pwm_port");
> +	for_each_child_of_node(pwm_np, child) {
> +		aspeed_create_pwm_port(child, priv, pwm_index++,
> +				       group_index++);
> +		of_node_put(child);

This is wrong (was there a 0day about it ? I dont recall).

> +	}
> +	of_node_put(pwm_np);
> +	fan_tach_np = of_get_child_by_name(np, "fan_tach_channel");
> +	for_each_child_of_node(fan_tach_np, child) {
> +		aspeed_create_fan_tach_channel(&pdev->dev, child, priv,
> +					       fan_index++, group_index++);
> +		of_node_put(child);

Wrong.

> +	}
> +	of_node_put(fan_tach_np);
> +	of_node_put(np);

I may be wrong, but I don't see why this would be needed.

> +
> +	hwmon = devm_hwmon_device_register_with_groups(&pdev->dev,
> +						       "aspeed_pwm_tacho",
> +						       priv, priv->groups);
> +	if (IS_ERR(hwmon))
> +		return PTR_ERR(hwmon);

return PTR_ERR_OR_ZERO(hwmon);

> +
> +	return 0;
> +}
> +
> +static const struct of_device_id of_pwm_tacho_match_table[] = {
> +	{ .compatible = "aspeed,aspeed2400-pwm-tacho", },
> +	{ .compatible = "aspeed,aspeed2500-pwm-tacho", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, of_pwm_tacho_match_table);
> +
> +static struct platform_driver aspeed_pwm_tacho_driver = {
> +	.probe		= aspeed_pwm_tacho_probe,
> +	.driver		= {
> +		.name	= "aspeed_pwm_tacho",
> +		.owner	= THIS_MODULE,

not needed.

> +		.of_match_table = of_pwm_tacho_match_table,
> +	},
> +};
> +
> +module_platform_driver(aspeed_pwm_tacho_driver);
> +
> +MODULE_AUTHOR("Jaghathiswari Rankappagounder Natarajan <jaghu at google.com>");
> +MODULE_DESCRIPTION("ASPEED PWM and Fan Tacho device driver");
> +MODULE_LICENSE("GPL");
> --
> 2.11.0.390.gc69c2f50cf-goog
>
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