[PATCH 4/4] hwmon: Support Aspeed AST2600 PWM/Fan tachometer
Guenter Roeck
linux at roeck-us.net
Fri Dec 11 03:16:53 AEDT 2020
On Wed, Dec 09, 2020 at 03:59:20PM +0800, Troy Lee wrote:
> Add Aspeed AST2600 PWM/Fan tacho driver. AST2600 has 16 PWM channel and
> 16 FAN tacho channel.
>
> Signed-off-by: Troy Lee <troy_lee at aspeedtech.com>
> ---
> drivers/hwmon/Kconfig | 10 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/aspeed2600-pwm-tacho.c | 1053 ++++++++++++++++++++++++++
> 3 files changed, 1064 insertions(+)
> create mode 100644 drivers/hwmon/aspeed2600-pwm-tacho.c
>
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
> index 9aa89d7d4193..097c01430259 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -400,6 +400,16 @@ config SENSORS_ASPEED
> This driver can also be built as a module. If so, the module
> will be called aspeed_pwm_tacho.
>
> +config SENSORS_ASPEED2600_PWM_TACHO
> + tristate "ASPEED AST2600 PWM and Fan Tachometer"
> + depends on THERMAL || THERMAL=n
> + help
> + This driver provides support for ASPEED AST2600 PWM
> + and Fan Tacho controllers.
> +
> + This driver can also be built as a module. If so, the module
> + will be called aspeed2600-pwm-tacho.
> +
> config SENSORS_ATXP1
> tristate "Attansic ATXP1 VID controller"
> depends on I2C
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
> index ae41ee71a71b..10be45768d36 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -52,6 +52,7 @@ obj-$(CONFIG_SENSORS_ARM_SCPI) += scpi-hwmon.o
> obj-$(CONFIG_SENSORS_AS370) += as370-hwmon.o
> obj-$(CONFIG_SENSORS_ASC7621) += asc7621.o
> obj-$(CONFIG_SENSORS_ASPEED) += aspeed-pwm-tacho.o
> +obj-$(CONFIG_SENSORS_ASPEED2600_PWM_TACHO) += aspeed2600-pwm-tacho.o
> obj-$(CONFIG_SENSORS_ATXP1) += atxp1.o
> obj-$(CONFIG_SENSORS_AXI_FAN_CONTROL) += axi-fan-control.o
> obj-$(CONFIG_SENSORS_BT1_PVT) += bt1-pvt.o
> diff --git a/drivers/hwmon/aspeed2600-pwm-tacho.c b/drivers/hwmon/aspeed2600-pwm-tacho.c
> new file mode 100644
> index 000000000000..083eb3b253ff
> --- /dev/null
> +++ b/drivers/hwmon/aspeed2600-pwm-tacho.c
> @@ -0,0 +1,1053 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) ASPEED Technology 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/errno.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>
> +#include <linux/reset.h>
> +#include <linux/regmap.h>
> +#include <linux/thermal.h>
> +/**********************************************************
> + * PWM HW register offset define
> + *********************************************************/
> +//PWM Control Register
Please no C++ comments, and please use standard multi-line comments.
> +#define ASPEED_PWM_CTRL_CH(ch) ((ch * 0x10) + 0x00)
> +//PWM Duty Cycle Register
> +#define ASPEED_PWM_DUTY_CYCLE_CH(ch) ((ch * 0x10) + 0x04)
> +//TACH Control Register
> +#define ASPEED_TACHO_CTRL_CH(ch) ((ch * 0x10) + 0x08)
(ch)
> +//TACH Status Register
> +#define ASPEED_TACHO_STS_CH(x) ((x * 0x10) + 0x0C)
(x)
> +/**********************************************************
> + * PWM register Bit field
> + *********************************************************/
> +/*PWM_CTRL */
> +#define PWM_LOAD_SEL_AS_WDT_BIT (19) //load selection as WDT
> +#define PWM_DUTY_LOAD_AS_WDT_EN BIT(18) //enable PWM duty load as WDT
> +#define PWM_DUTY_SYNC_DIS BIT(17) //disable PWM duty sync
> +#define PWM_CLK_ENABLE BIT(16) //enable PWM clock
> +#define PWM_LEVEL_OUTPUT BIT(15) //output PWM level
> +#define PWM_INVERSE BIT(14) //inverse PWM pin
> +#define PWM_OPEN_DRAIN_EN BIT(13) //enable open-drain
> +#define PWM_PIN_EN BIT(12) //enable PWM pin
> +#define PWM_CLK_DIV_H_MASK (0xf << 8) //PWM clock division H bit [3:0]
> +#define PWM_CLK_DIV_L_MASK (0xff) //PWM clock division H bit [3:0]
> +/* [19] */
> +#define LOAD_SEL_FALLING 0
> +#define LOAD_SEL_RIGING 1
> +
> +/*PWM_DUTY_CYCLE */
> +#define PWM_PERIOD_BIT (24) //pwm period bit [7:0]
> +#define PWM_PERIOD_BIT_MASK (0xff << 24) //pwm period bit [7:0]
> +#define PWM_RISING_FALLING_AS_WDT_BIT (16)
> +#define PWM_RISING_FALLING_AS_WDT_MASK (0xff << 16) //pwm rising/falling point bit [7:0] as WDT
> +#define PWM_RISING_FALLING_MASK (0xffff)
> +#define PWM_FALLING_POINT_BIT (8) //pwm falling point bit [7:0]
> +#define PWM_RISING_POINT_BIT (0) //pwm rising point bit [7:0]
> +/* [31:24] */
> +#define DEFAULT_PWM_PERIOD 0xff
> +
> +/*PWM_TACHO_CTRL */
> +#define TACHO_IER BIT(31) //enable tacho interrupt
> +#define TACHO_INVERS_LIMIT BIT(30) //inverse tacho limit comparison
> +#define TACHO_LOOPBACK BIT(29) //tacho loopback
> +#define TACHO_ENABLE BIT(28) //{enable tacho}
> +#define TACHO_DEBOUNCE_MASK (0x3 << 26) //{tacho de-bounce}
> +#define TACHO_DEBOUNCE_BIT (26) //{tacho de-bounce}
> +#define TECHIO_EDGE_MASK (0x3 << 24) //tacho edge}
> +#define TECHIO_EDGE_BIT (24) //tacho edge}
> +#define TACHO_CLK_DIV_T_MASK (0xf << 20)
> +#define TACHO_CLK_DIV_BIT (20)
> +#define TACHO_THRESHOLD_MASK (0xfffff) //tacho threshold bit
> +/* [27:26] */
> +#define DEBOUNCE_3_CLK 0x00 /* 10b */
> +#define DEBOUNCE_2_CLK 0x01 /* 10b */
> +#define DEBOUNCE_1_CLK 0x02 /* 10b */
> +#define DEBOUNCE_0_CLK 0x03 /* 10b */
> +/* [25:24] */
> +#define F2F_EDGES 0x00 /* 10b */
> +#define R2R_EDGES 0x01 /* 10b */
> +#define BOTH_EDGES 0x02 /* 10b */
> +/* [23:20] */
> +/* Cover rpm range 5~5859375 */
> +#define DEFAULT_TACHO_DIV 5
> +
> +/*PWM_TACHO_STS */
> +#define TACHO_ISR BIT(31) //interrupt status and clear
> +#define PWM_OUT BIT(25) //{pwm_out}
> +#define PWM_OEN BIT(24) //{pwm_oeN}
> +#define TACHO_DEB_INPUT BIT(23) //tacho deB input
> +#define TACHO_RAW_INPUT BIT(22) //tacho raw input}
> +#define TACHO_VALUE_UPDATE BIT(21) //tacho value updated since the last read
> +#define TACHO_FULL_MEASUREMENT BIT(20) //{tacho full measurement}
> +#define TACHO_VALUE_MASK 0xfffff //tacho value bit [19:0]}
> +/**********************************************************
> + * Software setting
> + *********************************************************/
> +#define DEFAULT_TARGET_PWM_FREQ 25000
> +#define DEFAULT_FAN_PULSE_PR 2
> +#define MAX_CDEV_NAME_LEN 16
> +
> +struct aspeed_pwm_channel_params {
> + int target_freq;
> + int pwm_freq;
> + int load_wdt_rising_falling_pt;
> + int load_wdt_selection; //0: rising , 1: falling
> + int load_wdt_enable;
> + int duty_sync_enable;
> + int invert_pin;
> + u8 rising;
> + u8 falling;
> +};
> +
> +static struct aspeed_pwm_channel_params default_pwm_params[] = {
> + [0] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 1,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
I am in general very much opposed to include default configurations
in hwmon drivers. Configuration should be provided through devicetree,
or through platform data.
> + [1] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [2] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [3] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [4] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [5] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [6] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [7] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [8] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [9] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [10] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [11] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [12] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [13] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [14] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> + [15] = {
> + .target_freq = 25000,
> + .load_wdt_rising_falling_pt = 0x10,
> + .load_wdt_selection = LOAD_SEL_FALLING,
> + .load_wdt_enable = 0,
> + .duty_sync_enable = 0,
> + .invert_pin = 0,
> + .rising = 0x00,
> + .falling = 0x0a,
> + },
> +};
> +
> +struct aspeed_tacho_channel_params {
> + int limited_inverse;
> + u16 threshold;
> + u8 tacho_edge;
> + u8 tacho_debounce;
> + u8 pulse_pr;
> + u32 divide;
> +};
> +
> +
> +static struct aspeed_tacho_channel_params default_tacho_params[] = {
> + [0] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
Same as above.
> + },
> + [1] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [2] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [3] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [4] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [5] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [6] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [7] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [8] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [9] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [10] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [11] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [12] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [13] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [14] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> + [15] = {
> + .limited_inverse = 0,
> + .threshold = 0,
> + .tacho_edge = F2F_EDGES,
> + .tacho_debounce = DEBOUNCE_3_CLK,
> + .pulse_pr = DEFAULT_FAN_PULSE_PR,
> + .divide = 8,
> + },
> +};
> +
> +struct aspeed_pwm_tachometer_data {
> + struct regmap *regmap;
> + unsigned long clk_freq;
> + struct reset_control *reset;
> + bool pwm_present[16];
> + bool fan_tach_present[16];
> + struct aspeed_pwm_channel_params *pwm_channel;
> + struct aspeed_tacho_channel_params *tacho_channel;
> + /* for thermal */
> + struct aspeed_cooling_device *cdev[8];
This makes me wonder if this should be a thermal driver instead.
Any thoughts ?
> + /* for hwmon */
> + const struct attribute_group *groups[3];
> +};
> +
> +struct aspeed_cooling_device {
> + char name[16];
> + struct aspeed_pwm_tachometer_data *priv;
> + struct thermal_cooling_device *tcdev;
> + int pwm_channel;
> + u8 *cooling_levels;
> + u8 max_state;
> + u8 cur_state;
> +};
> +
> +static int regmap_aspeed_pwm_tachometer_reg_write(void *context, unsigned int reg,
> + unsigned int val)
> +{
> + void __iomem *regs = (void __iomem *)context;
> +
> + writel(val, regs + reg);
> + return 0;
> +}
> +
> +static int regmap_aspeed_pwm_tachometer_reg_read(void *context, unsigned int reg,
> + unsigned int *val)
> +{
> + void __iomem *regs = (void __iomem *)context;
> +
> + *val = readl(regs + reg);
> + return 0;
> +}
> +
> +static const struct regmap_config aspeed_pwm_tachometer_regmap_config = {
> + .reg_bits = 32,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .max_register = 0x100,
> + .reg_write = regmap_aspeed_pwm_tachometer_reg_write,
> + .reg_read = regmap_aspeed_pwm_tachometer_reg_read,
> + .fast_io = true,
> +};
> +
> +static void aspeed_set_pwm_channel_enable(struct regmap *regmap, u8 pwm_channel,
> + bool enable)
> +{
> + regmap_update_bits(regmap, ASPEED_PWM_CTRL_CH(pwm_channel),
> + (PWM_CLK_ENABLE | PWM_PIN_EN),
> + enable ? (PWM_CLK_ENABLE | PWM_PIN_EN) : 0);
Unnecessary ()
> +}
> +
> +static void aspeed_set_fan_tach_ch_enable(struct aspeed_pwm_tachometer_data *priv, u8 fan_tach_ch,
> + bool enable, u32 tacho_div)
This function is only called with enable == true. Please no unnecessary
complexity.
> +{
> + u32 reg_value = 0;
Unnecessary initialization.
> +
> + if (enable) {
> + /* divide = 2^(tacho_div*2) */
> + priv->tacho_channel[fan_tach_ch].divide = 1 << (tacho_div << 1);
> +
> + reg_value = TACHO_ENABLE |
> + (priv->tacho_channel[fan_tach_ch].tacho_edge << TECHIO_EDGE_BIT) |
> + (tacho_div << TACHO_CLK_DIV_BIT) |
> + (priv->tacho_channel[fan_tach_ch].tacho_debounce << TACHO_DEBOUNCE_BIT);
> +
> + if (priv->tacho_channel[fan_tach_ch].limited_inverse)
> + reg_value |= TACHO_INVERS_LIMIT;
> +
> + if (priv->tacho_channel[fan_tach_ch].threshold)
> + reg_value |= (TACHO_IER | priv->tacho_channel[fan_tach_ch].threshold);
> +
> + regmap_write(priv->regmap, ASPEED_TACHO_CTRL_CH(fan_tach_ch), reg_value);
> + } else
> + regmap_update_bits(priv->regmap, ASPEED_TACHO_CTRL_CH(fan_tach_ch), TACHO_ENABLE, 0);
> +}
> +
> +/*
> + * The PWM frequency = HCLK(200Mhz) / (clock division L bit *
> + * clock division H bit * (period bit + 1))
> + */
> +static void aspeed_set_pwm_channel_fan_ctrl(struct device *dev,
> + struct aspeed_pwm_tachometer_data *priv,
> + u8 index, u8 fan_ctrl)
> +{
> + u32 duty_value, ctrl_value;
> + u32 div_h, div_l, cal_freq;
> + u8 div_found;
div_found is used as boolean. Declaring it u8 makes the code more complex
on many architectures. Please use bool.
> +
> + if (fan_ctrl == 0) {
> + aspeed_set_pwm_channel_enable(priv->regmap, index, false);
Consider using return; here and drop else.
> + } else {
> + cal_freq = priv->clk_freq / (DEFAULT_PWM_PERIOD + 1);
> + //calculate for target frequence
> + div_found = 0;
> + for (div_h = 0; div_h < 0x10; div_h++) {
> + for (div_l = 0; div_l < 0x100; div_l++) {
> + dev_dbg(dev, "div h %x, l : %x , freq %ld \n", div_h, div_l,
> + (cal_freq / (BIT(div_h) * (div_l + 1))));
> + if ((cal_freq / (BIT(div_h) * (div_l + 1))) < priv->pwm_channel[index].target_freq) {
> + div_found = 1;
> + break;
> + }
> + }
> + if (div_found)
> + break;
> + }
This double loop is quite expensive. Are yu sure there is no better means to
determine the fan divider ? By using a binary search, maybe ?
Also, what happens if div_found is false at the end ? The code below suggests
that this would be problematic.
> +
> + priv->pwm_channel[index].pwm_freq = cal_freq / (BIT(div_h) * (div_l + 1));
> + dev_dbg(dev, "div h %x, l : %x pwm out clk %d \n", div_h, div_l,
> + priv->pwm_channel[index].pwm_freq);
> + dev_dbg(dev, "hclk %ld, target pwm freq %d, real pwm freq %d\n", priv->clk_freq,
> + priv->pwm_channel[index].target_freq, priv->pwm_channel[index].pwm_freq);
> +
> + ctrl_value = (div_h << 8) | div_l;
> +
> + duty_value = (DEFAULT_PWM_PERIOD << PWM_PERIOD_BIT) |
> + (0 << PWM_RISING_POINT_BIT) | (fan_ctrl << PWM_FALLING_POINT_BIT);
> +
> + if (priv->pwm_channel[index].load_wdt_enable) {
> + ctrl_value |= PWM_DUTY_LOAD_AS_WDT_EN;
> + ctrl_value |= priv->pwm_channel[index].load_wdt_selection << PWM_LOAD_SEL_AS_WDT_BIT;
> + duty_value |= (priv->pwm_channel[index].load_wdt_rising_falling_pt << PWM_RISING_FALLING_AS_WDT_BIT);
> + }
> +
> + regmap_write(priv->regmap, ASPEED_PWM_DUTY_CYCLE_CH(index), duty_value);
> + regmap_write(priv->regmap, ASPEED_PWM_CTRL_CH(index), ctrl_value);
> +
> + aspeed_set_pwm_channel_enable(priv->regmap, index, true);
> + }
> +}
> +
> +static int aspeed_get_fan_tach_ch_rpm(struct device *dev, struct aspeed_pwm_tachometer_data *priv,
> + u8 fan_tach_ch)
> +{
> + u32 raw_data, tach_div, clk_source, val;
> + int i, retries = 3;
> +
> + for (i = 0; i < retries; i++) {
> + regmap_read(priv->regmap, ASPEED_TACHO_STS_CH(fan_tach_ch), &val);
> + if (TACHO_FULL_MEASUREMENT & val)
No Yoda programming please.
> + break;
> + }
> +
> + raw_data = val & TACHO_VALUE_MASK;
> + if (raw_data == 0xfffff)
> + return 0;
> +
> + raw_data += 1;
> +
> + /*
> + * We need the mode to determine if the raw_data is double (from
> + * counting both edges).
> + */
> + tach_div = raw_data * (priv->tacho_channel[fan_tach_ch].divide) * (priv->tacho_channel[fan_tach_ch].pulse_pr);
> +
> + dev_dbg(dev, "clk %ld, raw_data %d , tach_div %d \n", priv->clk_freq, raw_data, tach_div);
> + clk_source = priv->clk_freq;
> +
> + if (raw_data == 0)
> + return 0;
How would raw_data ever be 0 here ? And why check it after using it,
and not before ?
> +
> + return ((clk_source / tach_div) * 60);
> +
> +}
> +
> +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;
> + struct aspeed_pwm_tachometer_data *priv = dev_get_drvdata(dev);
> + long fan_ctrl;
> + u8 org_falling = priv->pwm_channel[index].falling;
> +
> + ret = kstrtol(buf, 10, &fan_ctrl);
> + if (ret != 0)
> + return ret;
> +
> + if (fan_ctrl < 0 || fan_ctrl > DEFAULT_PWM_PERIOD)
> + return -EINVAL;
Please use kstrtoul().
> +
> + if (priv->pwm_channel[index].falling == fan_ctrl)
> + return count;
> +
> + priv->pwm_channel[index].falling = fan_ctrl;
> +
> + if (fan_ctrl == 0)
> + aspeed_set_pwm_channel_enable(priv->regmap, index, false);
> + else {
> + if (fan_ctrl == DEFAULT_PWM_PERIOD)
> + regmap_update_bits(priv->regmap,
> + ASPEED_PWM_DUTY_CYCLE_CH(index),
> + GENMASK(15, 0), 0);
> + else
> + regmap_update_bits(priv->regmap,
> + ASPEED_PWM_DUTY_CYCLE_CH(index),
> + GENMASK(15, 8),
> + (fan_ctrl << PWM_FALLING_POINT_BIT));
> + }
> +
> + if (org_falling == 0)
> + aspeed_set_pwm_channel_enable(priv->regmap, index, true);
> +
> + 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;
> + struct aspeed_pwm_tachometer_data *priv = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "%u\n", priv->pwm_channel[index].falling);
> +}
> +
> +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;
> + int rpm;
> + struct aspeed_pwm_tachometer_data *priv = dev_get_drvdata(dev);
> +
> + rpm = aspeed_get_fan_tach_ch_rpm(dev, priv, index);
> + if (rpm < 0)
> + return rpm;
> +
> + return sprintf(buf, "%d\n", rpm);
> +}
> +
> +static umode_t pwm_is_visible(struct kobject *kobj,
> + struct attribute *a, int index)
> +{
> + struct device *dev = container_of(kobj, struct device, kobj);
> + struct aspeed_pwm_tachometer_data *priv = dev_get_drvdata(dev);
> +
> + if (!priv->pwm_present[index])
> + return 0;
> + return a->mode;
> +}
> +
> +static umode_t fan_dev_is_visible(struct kobject *kobj,
> + struct attribute *a, int index)
> +{
> + struct device *dev = container_of(kobj, struct device, kobj);
> + struct aspeed_pwm_tachometer_data *priv = dev_get_drvdata(dev);
> +
> + if (!priv->fan_tach_present[index])
> + return 0;
> + return a->mode;
> +}
> +
> +static SENSOR_DEVICE_ATTR(pwm0, 0644,
> + show_pwm, set_pwm, 0);
> +static SENSOR_DEVICE_ATTR(pwm1, 0644,
> + show_pwm, set_pwm, 1);
> +static SENSOR_DEVICE_ATTR(pwm2, 0644,
> + show_pwm, set_pwm, 2);
> +static SENSOR_DEVICE_ATTR(pwm3, 0644,
> + show_pwm, set_pwm, 3);
> +static SENSOR_DEVICE_ATTR(pwm4, 0644,
> + show_pwm, set_pwm, 4);
> +static SENSOR_DEVICE_ATTR(pwm5, 0644,
> + show_pwm, set_pwm, 5);
> +static SENSOR_DEVICE_ATTR(pwm6, 0644,
> + show_pwm, set_pwm, 6);
> +static SENSOR_DEVICE_ATTR(pwm7, 0644,
> + show_pwm, set_pwm, 7);
> +static SENSOR_DEVICE_ATTR(pwm8, 0644,
> + show_pwm, set_pwm, 8);
> +static SENSOR_DEVICE_ATTR(pwm9, 0644,
> + show_pwm, set_pwm, 9);
> +static SENSOR_DEVICE_ATTR(pwm10, 0644,
> + show_pwm, set_pwm, 10);
> +static SENSOR_DEVICE_ATTR(pwm11, 0644,
> + show_pwm, set_pwm, 11);
> +static SENSOR_DEVICE_ATTR(pwm12, 0644,
> + show_pwm, set_pwm, 12);
> +static SENSOR_DEVICE_ATTR(pwm13, 0644,
> + show_pwm, set_pwm, 13);
> +static SENSOR_DEVICE_ATTR(pwm14, 0644,
> + show_pwm, set_pwm, 14);
> +static SENSOR_DEVICE_ATTR(pwm15, 0644,
> + show_pwm, set_pwm, 15);
> +static struct attribute *pwm_dev_attrs[] = {
> + &sensor_dev_attr_pwm0.dev_attr.attr,
> + &sensor_dev_attr_pwm1.dev_attr.attr,
> + &sensor_dev_attr_pwm2.dev_attr.attr,
> + &sensor_dev_attr_pwm3.dev_attr.attr,
> + &sensor_dev_attr_pwm4.dev_attr.attr,
> + &sensor_dev_attr_pwm5.dev_attr.attr,
> + &sensor_dev_attr_pwm6.dev_attr.attr,
> + &sensor_dev_attr_pwm7.dev_attr.attr,
> + &sensor_dev_attr_pwm8.dev_attr.attr,
> + &sensor_dev_attr_pwm9.dev_attr.attr,
> + &sensor_dev_attr_pwm10.dev_attr.attr,
> + &sensor_dev_attr_pwm11.dev_attr.attr,
> + &sensor_dev_attr_pwm12.dev_attr.attr,
> + &sensor_dev_attr_pwm13.dev_attr.attr,
> + &sensor_dev_attr_pwm14.dev_attr.attr,
> + &sensor_dev_attr_pwm15.dev_attr.attr,
> + NULL,
> +};
> +
> +static const struct attribute_group pwm_dev_group = {
> + .attrs = pwm_dev_attrs,
> + .is_visible = pwm_is_visible,
> +};
> +
> +static SENSOR_DEVICE_ATTR(fan0_input, 0444,
> + show_rpm, NULL, 0);
> +static SENSOR_DEVICE_ATTR(fan1_input, 0444,
> + show_rpm, NULL, 1);
> +static SENSOR_DEVICE_ATTR(fan2_input, 0444,
> + show_rpm, NULL, 2);
> +static SENSOR_DEVICE_ATTR(fan3_input, 0444,
> + show_rpm, NULL, 3);
> +static SENSOR_DEVICE_ATTR(fan4_input, 0444,
> + show_rpm, NULL, 4);
> +static SENSOR_DEVICE_ATTR(fan5_input, 0444,
> + show_rpm, NULL, 5);
> +static SENSOR_DEVICE_ATTR(fan6_input, 0444,
> + show_rpm, NULL, 6);
> +static SENSOR_DEVICE_ATTR(fan7_input, 0444,
> + show_rpm, NULL, 7);
> +static SENSOR_DEVICE_ATTR(fan8_input, 0444,
> + show_rpm, NULL, 8);
> +static SENSOR_DEVICE_ATTR(fan9_input, 0444,
> + show_rpm, NULL, 9);
> +static SENSOR_DEVICE_ATTR(fan10_input, 0444,
> + show_rpm, NULL, 10);
> +static SENSOR_DEVICE_ATTR(fan11_input, 0444,
> + show_rpm, NULL, 11);
> +static SENSOR_DEVICE_ATTR(fan12_input, 0444,
> + show_rpm, NULL, 12);
> +static SENSOR_DEVICE_ATTR(fan13_input, 0444,
> + show_rpm, NULL, 13);
> +static SENSOR_DEVICE_ATTR(fan14_input, 0444,
> + show_rpm, NULL, 14);
> +static SENSOR_DEVICE_ATTR(fan15_input, 0444,
> + show_rpm, NULL, 15);
> +static struct attribute *fan_dev_attrs[] = {
> + &sensor_dev_attr_fan0_input.dev_attr.attr,
> + &sensor_dev_attr_fan1_input.dev_attr.attr,
> + &sensor_dev_attr_fan2_input.dev_attr.attr,
> + &sensor_dev_attr_fan3_input.dev_attr.attr,
> + &sensor_dev_attr_fan4_input.dev_attr.attr,
> + &sensor_dev_attr_fan5_input.dev_attr.attr,
> + &sensor_dev_attr_fan6_input.dev_attr.attr,
> + &sensor_dev_attr_fan7_input.dev_attr.attr,
> + &sensor_dev_attr_fan8_input.dev_attr.attr,
> + &sensor_dev_attr_fan9_input.dev_attr.attr,
> + &sensor_dev_attr_fan10_input.dev_attr.attr,
> + &sensor_dev_attr_fan11_input.dev_attr.attr,
> + &sensor_dev_attr_fan12_input.dev_attr.attr,
> + &sensor_dev_attr_fan13_input.dev_attr.attr,
> + &sensor_dev_attr_fan14_input.dev_attr.attr,
> + &sensor_dev_attr_fan15_input.dev_attr.attr,
> + NULL
> +};
> +
> +static const struct attribute_group fan_dev_group = {
> + .attrs = fan_dev_attrs,
> + .is_visible = fan_dev_is_visible,
> +};
> +
> +static void aspeed_create_pwm_channel(struct device *dev, struct aspeed_pwm_tachometer_data *priv,
> + u8 pwm_channel, u32 target_pwm_freq)
> +{
> + priv->pwm_present[pwm_channel] = true;
> + priv->pwm_channel[pwm_channel].target_freq = target_pwm_freq;
> +
> + //use default
> + aspeed_set_pwm_channel_fan_ctrl(dev,
> + priv,
> + pwm_channel,
> + priv->pwm_channel[pwm_channel].falling);
> +}
> +
> +static void aspeed_create_fan_tach_channel(struct aspeed_pwm_tachometer_data *priv,
> + u8 *fan_tach_ch, int count,
> + u32 fan_pulse_pr, u32 tacho_div)
> +{
> + u8 val, index;
> +
> + for (val = 0; val < count; val++) {
> + index = fan_tach_ch[val];
> + priv->fan_tach_present[index] = true;
> + priv->tacho_channel[index].pulse_pr = fan_pulse_pr;
> + aspeed_set_fan_tach_ch_enable(priv, index, true, tacho_div);
> + }
> +}
> +
> +static int
> +aspeed_pwm_cz_get_max_state(struct thermal_cooling_device *tcdev,
> + unsigned long *state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + *state = cdev->max_state;
> +
> + return 0;
> +}
> +
> +static int
> +aspeed_pwm_cz_get_cur_state(struct thermal_cooling_device *tcdev,
> + unsigned long *state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + *state = cdev->cur_state;
> +
> + return 0;
> +}
> +
> +static int
> +aspeed_pwm_cz_set_cur_state(struct thermal_cooling_device *tcdev,
> + unsigned long state)
> +{
> + struct aspeed_cooling_device *cdev = tcdev->devdata;
> +
> + if (state > cdev->max_state)
> + return -EINVAL;
> +
> + cdev->cur_state = state;
> + cdev->priv->pwm_channel[cdev->pwm_channel].falling =
> + cdev->cooling_levels[cdev->cur_state];
> + aspeed_set_pwm_channel_fan_ctrl(&tcdev->device, cdev->priv, cdev->pwm_channel,
> + cdev->cooling_levels[cdev->cur_state]);
> +
> + return 0;
> +}
> +
> +static const struct thermal_cooling_device_ops aspeed_pwm_cool_ops = {
> + .get_max_state = aspeed_pwm_cz_get_max_state,
> + .get_cur_state = aspeed_pwm_cz_get_cur_state,
> + .set_cur_state = aspeed_pwm_cz_set_cur_state,
> +};
> +
> +static int aspeed_create_pwm_cooling(struct device *dev,
> + struct device_node *child,
> + struct aspeed_pwm_tachometer_data *priv,
> + u32 pwm_channel, u8 num_levels)
> +{
> + int ret;
> + struct aspeed_cooling_device *cdev;
> +
> + cdev = devm_kzalloc(dev, sizeof(*cdev), GFP_KERNEL);
> + if (!cdev)
> + return -ENOMEM;
> +
> + cdev->cooling_levels = devm_kzalloc(dev, num_levels, GFP_KERNEL);
> + if (!cdev->cooling_levels)
> + return -ENOMEM;
> +
> + cdev->max_state = num_levels - 1;
> + ret = of_property_read_u8_array(child, "cooling-levels",
> + cdev->cooling_levels,
> + num_levels);
> + if (ret) {
> + dev_err(dev, "Property 'cooling-levels' cannot be read.\n");
> + return ret;
> + }
> + snprintf(cdev->name, MAX_CDEV_NAME_LEN, "%s%d", child->name, pwm_channel);
> +
> + cdev->tcdev = thermal_of_cooling_device_register(child,
> + cdev->name,
> + cdev,
> + &aspeed_pwm_cool_ops);
> + if (IS_ERR(cdev->tcdev))
> + return PTR_ERR(cdev->tcdev);
> +
> + cdev->priv = priv;
> + cdev->pwm_channel = pwm_channel;
> +
> + priv->cdev[pwm_channel] = cdev;
> +
> + return 0;
> +}
> +
> +static int aspeed_pwm_create_fan(struct device *dev,
> + struct device_node *child,
> + struct aspeed_pwm_tachometer_data *priv)
> +{
> + u8 *fan_tach_ch;
> + u32 fan_pulse_pr;
> + u32 tacho_div;
> + u32 pwm_channel;
> + u32 target_pwm_freq = 0;
> + int ret, count;
> +
> + ret = of_property_read_u32(child, "reg", &pwm_channel);
> + if (ret)
> + return ret;
> +
> + ret = of_property_read_u32(child, "aspeed,pwm-freq", &target_pwm_freq);
> + if (ret)
> + target_pwm_freq = DEFAULT_TARGET_PWM_FREQ;
> +
> + aspeed_create_pwm_channel(dev, priv, (u8)pwm_channel, target_pwm_freq);
> +
> + ret = of_property_count_u8_elems(child, "cooling-levels");
> + if (ret > 0) {
> + if (IS_ENABLED(CONFIG_THERMAL)) {
> + ret = aspeed_create_pwm_cooling(dev, child, priv, pwm_channel,
> + ret);
> + if (ret)
> + return ret;
> + }
> + }
> +
> + count = of_property_count_u8_elems(child, "aspeed,fan-tach-ch");
> + if (count < 1)
> + return -EINVAL;
> +
> + fan_tach_ch = devm_kzalloc(dev, sizeof(*fan_tach_ch) * count,
> + GFP_KERNEL);
> + if (!fan_tach_ch)
> + return -ENOMEM;
> + ret = of_property_read_u8_array(child, "aspeed,fan-tach-ch",
> + fan_tach_ch, count);
> + if (ret)
> + return ret;
> +
> + ret = of_property_read_u32(child, "aspeed,pulse-pr", &fan_pulse_pr);
> + if (ret)
> + fan_pulse_pr = DEFAULT_FAN_PULSE_PR;
Are those properties declared as optional ?
> +
> + ret = of_property_read_u32(child, "aspeed,tacho-div", &tacho_div);
> + if (ret)
> + tacho_div = DEFAULT_TACHO_DIV;
> +
> + aspeed_create_fan_tach_channel(priv, fan_tach_ch, count, fan_pulse_pr, tacho_div);
> +
> + return 0;
> +}
> +
> +static int aspeed_pwm_tachometer_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *np, *child;
> + struct aspeed_pwm_tachometer_data *priv;
> + void __iomem *regs;
> + struct resource *res;
> + struct device *hwmon;
> + struct clk *clk;
> + int ret;
> +
> + np = dev->of_node;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -ENOENT;
Unnecessary error check. devm_ioremap_resource() does that (and
returns -EINVAL).
> + regs = devm_ioremap_resource(dev, res);
> + if (IS_ERR(regs))
> + return PTR_ERR(regs);
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->pwm_channel = default_pwm_params;
> + priv->tacho_channel = default_tacho_params;
> + priv->regmap = devm_regmap_init(dev, NULL, (__force void *)regs,
> + &aspeed_pwm_tachometer_regmap_config);
> + if (IS_ERR(priv->regmap))
> + return PTR_ERR(priv->regmap);
> +
> + clk = devm_clk_get(dev, NULL);
> + if (IS_ERR(clk))
> + return -ENODEV;
> + priv->clk_freq = clk_get_rate(clk);
> +
> + priv->reset = devm_reset_control_get(&pdev->dev, NULL);
> + if (IS_ERR(priv->reset)) {
> + dev_err(&pdev->dev, "can't get aspeed_pwm_tacho reset\n");
> + return PTR_ERR(priv->reset);
> + }
> +
> + //scu init
> + reset_control_assert(priv->reset);
> + reset_control_deassert(priv->reset);
> +
> + for_each_child_of_node(np, child) {
> + ret = aspeed_pwm_create_fan(dev, child, priv);
> + if (ret) {
> + of_node_put(child);
> + return ret;
> + }
> + }
> +
> + priv->groups[0] = &pwm_dev_group;
> + priv->groups[1] = &fan_dev_group;
> + priv->groups[2] = NULL;
> + dev_info(dev, "pwm tach probe done\n");
> + hwmon = devm_hwmon_device_register_with_groups(dev,
> + "aspeed_pwm_tachometer",
> + priv, priv->groups);
New drivers must use devm_hwmon_device_register_with_info().
> +
> + return PTR_ERR_OR_ZERO(hwmon);
> +}
> +
> +static const struct of_device_id of_pwm_tachometer_match_table[] = {
> + { .compatible = "aspeed,ast2600-pwm-tachometer", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, of_pwm_tachometer_match_table);
> +
> +static struct platform_driver aspeed_pwm_tachometer_driver = {
> + .probe = aspeed_pwm_tachometer_probe,
> + .driver = {
> + .name = "aspeed_pwm_tachometer",
> + .of_match_table = of_pwm_tachometer_match_table,
> + },
> +};
> +
> +module_platform_driver(aspeed_pwm_tachometer_driver);
> +
> +MODULE_AUTHOR("Ryan Chen <ryan_chen at aspeedtech.com>");
> +MODULE_DESCRIPTION("ASPEED PWM and Fan Tachometer device driver");
> +MODULE_LICENSE("GPL");
> --
> 2.17.1
>
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