RE: [PATCH] hwmon: add support for SMSC EMC2305/03/02/01 fan controller
From: Biwen Li
Date: Mon Sep 28 2020 - 06:59:05 EST
Hi All,
The patch has a problem as follows,
root@localhost:~# cat /sys/class/hwmon/hwmon0/pwm1
[ 103.150689] Unable to handle kernel paging request at virtual address 00329c10ffff0026
[ 103.158651] Mem abort info:
[ 103.161443] ESR = 0x96000004
[ 103.164486] EC = 0x25: DABT (current EL), IL = 32 bits
[ 103.169789] SET = 0, FnV = 0
[ 103.172835] EA = 0, S1PTW = 0
[ 103.175963] Data abort info:
[ 103.178841] ISV = 0, ISS = 0x00000004
[ 103.182672] CM = 0, WnR = 0
[ 103.185640] [00329c10ffff0026] address between user and kernel address ranges
[ 103.192778] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 103.198337] Modules linked in: emc2305
[ 103.202076] CPU: 3 PID: 940 Comm: cat Not tainted 5.4.3-00011-gd80981868cef-dirty #7
[ 103.209805] Hardware name: NXP Layerscape LX2160ABLUEBOX3 (DT)
[ 103.215625] pstate: 60000005 (nZCv daif -PAN -UAO)
[ 103.220409] pc : i2c_smbus_xfer+0x50/0x110
[ 103.220409] pc : i2c_smbus_xfer+0x50/0x110
[ 103.224494] lr : i2c_smbus_read_byte_data+0x40/0x70
[ 103.229357] sp : ffff800010abbb50
[ 103.232659] x29: ffff800010abbb50 x28: ffff0026d7fb6480
[ 103.237958] x27: ffff0026d7fb6480 x26: ffff0026d5329be8
[ 103.243256] x25: ffff800010abbbc6 x24: 0000000000000002
[ 103.248555] x23: 0000000000000032 x22: 0000000000000001
[ 103.253854] x21: 0000000000000000 x20: 0000000000000000
[ 103.259152] x19: ffff0026d8011404 x18: 0000000000000000
[ 103.264451] x17: 0000000000000000 x16: ffffaea1e5532f08
[ 103.269749] x15: 0000000000000000 x14: 0000000000000000
[ 103.275047] x13: 0000000000000000 x12: 0000000000000000
[ 103.280346] x11: 0000000000000000 x10: 0000000000000000
[ 103.285645] x9 : 0000000000000000 x8 : ffff0026d3f1d000
[ 103.290943] x7 : ffffaea1e6919000 x6 : ffff800010abbbc6
[ 103.296241] x5 : 0000000000000002 x4 : 0000000000000032
[ 103.301540] x3 : 0000000000000001 x2 : d5329c10ffff0026
[ 103.306839] x1 : 0000000000000002 x0 : ffff0026d8011404
[ 103.312137] Call trace:
[ 103.314572] i2c_smbus_xfer+0x50/0x110
[ 103.318308] i2c_smbus_read_byte_data+0x40/0x70
[ 103.322829] read_u8_from_i2c+0x24/0x60 [emc2305]
[ 103.327520] emc2305_update_fan+0x9c/0x158 [emc2305]
[ 103.332472] pwm_enable_show+0x1c/0x50 [emc2305]
[ 103.337078] dev_attr_show+0x20/0x60
[ 103.340643] sysfs_kf_seq_show+0xbc/0x148
[ 103.344640] kernfs_seq_show+0x28/0x30
[ 103.348377] seq_read+0xcc/0x4c8
[ 103.351592] kernfs_fop_read+0x140/0x200
[ 103.355503] __vfs_read+0x18/0x38
[ 103.358804] vfs_read+0x98/0x188
[ 103.362020] ksys_read+0x68/0xf8
[ 103.365235] __arm64_sys_read+0x18/0x20
[ 103.369059] el0_svc_common.constprop.2+0x64/0x160
[ 103.373837] el0_svc_handler+0x20/0x80
[ 103.377573] el0_svc+0x8/0xc
[ 103.380442] Code: 54000368 f9401262 52800041 aa1303e0 (f9400042)
[ 103.386523] ---[ end trace 0f9e87c54e49a984 ]---
Any comments about this? Welcome for your comments.
>
> From: Reinhard Pfau <pfau@xxxxxxxx>
>
> Add support for SMSC EMC2305, EMC2303, EMC2302, EMC2301 fan
> controller chips.
> The driver primary supports the EMC2305 chip which provides RPM-based
> PWM control and monitoring for up to 5 fans.
>
> According to the SMSC data sheets the EMC2303, EMC2302 and EMC2301
> chips have basically the same functionality and register layout, but support less
> fans and (in case of EMC2302 and EMC2301) less possible I2C addresses.
> The driver supports them, too.
>
> The driver supports configuration via devicetree. This can also be used to
> restrict the fans exposed via sysfs (see doc for details).
>
> Signed-off-by: Reinhard Pfau <pfau@xxxxxxxx>
> Signed-off-by: Biwen Li <biwen.li@xxxxxxx>
> ---
> .../devicetree/bindings/hwmon/emc2305.txt | 33 +
> Documentation/hwmon/emc2305.rst | 34 +
> MAINTAINERS | 8 +
> drivers/hwmon/Kconfig | 10 +
> drivers/hwmon/Makefile | 1 +
> drivers/hwmon/emc2305.c | 689
> ++++++++++++++++++
> 6 files changed, 775 insertions(+)
> create mode 100644
> Documentation/devicetree/bindings/hwmon/emc2305.txt
> create mode 100644 Documentation/hwmon/emc2305.rst create mode
> 100644 drivers/hwmon/emc2305.c
>
> diff --git a/Documentation/devicetree/bindings/hwmon/emc2305.txt
> b/Documentation/devicetree/bindings/hwmon/emc2305.txt
> new file mode 100644
> index 000000000000..73165120b88a
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/emc2305.txt
> @@ -0,0 +1,33 @@
> +EMC2305 (I2C)
> +
> +This device is a RPM-based PWM Fan Speed Controller for up to 5 fans.
> +Each fan can beconfigured individually:
> +
> + - The PWM mode:
> + 0: PWM is disabled
> + 3: RPM based PWM
> +
> + - The fan divisor (for RPM mesaurement)
> + 1, 2 ,4 or 8
> +
> + - The target RPM speed (for RPM based PWM mode)
> + max 16000 (according to data sheet)
> +
> +
> + - The /emc2305 node
> +
> + Required properties:
> +
> + - compatible : must be "smsc,emc2305"
> + - reg : I2C bus address of the device
> + - #address-cells : must be <1>
> + - #size-cells : must be <0>
> +
> + Example EMC2305 node:
> +
> + emc2305@2C {
> + compatible = "smsc,emc2305";
> + reg = <0x2C>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + }
> diff --git a/Documentation/hwmon/emc2305.rst
> b/Documentation/hwmon/emc2305.rst new file mode 100644 index
> 000000000000..d0cebae09ffd
> --- /dev/null
> +++ b/Documentation/hwmon/emc2305.rst
> @@ -0,0 +1,34 @@
> +Kernel driver emc2305
> +=====================
> +
> +Supported chips:
> + * SMSC EMC2305, EMC2303, EMC2302, EMC2301
> + Adresses scanned: I2C 0x2c, 0x2d, 0x2e, 0x2f, 0x4c, 0x4d
> + Prefixes: 'emc2305', 'emc2303', 'emc2302', 'emc2301'
> + Datasheet: Publicly available at the MICROCHIP website :
> +
> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fww1.m
> i
> +crochip.com%2Fdownloads%2Fen%2FDeviceDoc%2F2305.pdf&data=02
> %7C01%7C
> +biwen.li%40nxp.com%7Cef95cc6d971c433d699808d8639c8b20%7C686ea1
> d3bc2b4c6
> +fa92cd99c5c301635%7C0%7C1%7C637368871279812461&sdata=1SaL
> 9ZOOTdEpMY
> +yXLQ%2F3KjbsHTgJ5UzK7o5ltsiBU5Y%3D&reserved=0
> +
> +Authors:
> + Reinhard Pfau, Guntermann & Drunck GmbH <pfau@xxxxxxxx>
> + Biwen Li <biwen.li@xxxxxxx>
> +
> +Description
> +-----------
> +
> +The SMSC EMC2305 is a fan controller for up to 5 fans.
> +The EMC2303 has the same functionality but supports only up to 3 fans.
> +
> +The EMC2302 supports 2 fans and the EMC2301 1 fan. These chips support
> +less possible I2C addresses.
> +
> +Fan rotation speeds are reported in RPM.
> +The driver supports the RPM based PWM control to keep a fan at a desired
> speed.
> +To enable this function for a fan, write 3 to pwm<num>_enable and the
> +desired fan speed to fan<num>_target.
> +
> +
> +Devicetree
> +----------
> +
> +Configuration is also possible via devicetree:
> +Documentation/devicetree/bindings/hwmon/emc2305.txt
> diff --git a/MAINTAINERS b/MAINTAINERS
> index b526b8a66f8a..a506e8071259 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -15013,6 +15013,14 @@ S: Maintained
> F: Documentation/hwmon/emc2103.rst
> F: drivers/hwmon/emc2103.c
>
> +SMSC EMC2305 HARDWARE MONITOR DRIVER
> +M: Biwen Li <biwen.li@xxxxxxx>
> +L: lm-sensors@xxxxxxxxxxxxxx
> +S: Maintained
> +F: Documentation/hwmon/emc2305
> +F: Documentation/devicetree/bindings/hwmon/emc2305.txt
> +F: drivers/hwmon/emc2305.c
> +
> SMSC SCH5627 HARDWARE MONITOR DRIVER
> M: Hans de Goede <hdegoede@xxxxxxxxxx>
> L: linux-hwmon@xxxxxxxxxxxxxxx
> diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index
> 2fa4666d5b07..5ab3e975517a 100644
> --- a/drivers/hwmon/Kconfig
> +++ b/drivers/hwmon/Kconfig
> @@ -1457,6 +1457,16 @@ config SENSORS_EMC2103
> This driver can also be built as a module. If so, the module
> will be called emc2103.
>
> +config SENSORS_EMC2305
> + tristate "SMSC EMC2305"
> + depends on I2C
> + help
> + If you say yes here you get support for the SMSC EMC2305
> + fan controller chips.
> +
> + This driver can also be built as a module. If so, the module
> + will be called emc2305.
> +
> config SENSORS_EMC6W201
> tristate "SMSC EMC6W201"
> depends on I2C
> diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index
> b033e6733b56..b6377d32a2c9 100644
> --- a/drivers/hwmon/Makefile
> +++ b/drivers/hwmon/Makefile
> @@ -60,6 +60,7 @@ obj-$(CONFIG_SENSORS_DS620) += ds620.o
> obj-$(CONFIG_SENSORS_DS1621) += ds1621.o
> obj-$(CONFIG_SENSORS_EMC1403) += emc1403.o
> obj-$(CONFIG_SENSORS_EMC2103) += emc2103.o
> +obj-$(CONFIG_SENSORS_EMC2305) += emc2305.o
> obj-$(CONFIG_SENSORS_EMC6W201) += emc6w201.o
> obj-$(CONFIG_SENSORS_F71805F) += f71805f.o
> obj-$(CONFIG_SENSORS_F71882FG) += f71882fg.o
> diff --git a/drivers/hwmon/emc2305.c b/drivers/hwmon/emc2305.c new file
> mode 100644 index 000000000000..d0c99f9b7434
> --- /dev/null
> +++ b/drivers/hwmon/emc2305.c
> @@ -0,0 +1,689 @@
> +/*
> + * emc2305.c - hwmon driver for SMSC EMC2305 fan controller
> + * (C) Copyright 2013
> + * Copyright 2020 NXP
> + * Reinhard Pfau, Guntermann & Drunck GmbH <pfau@xxxxxxxx>
> + * Biwen Li <biwen.li@xxxxxxx>
> + *
> + * Based on emc2103 driver by SMSC.
> + *
> + * Datasheet available at:
> + *
> +https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fww1.m
> i
> +crochip.com%2Fdownloads%2Fen%2FDeviceDoc%2F2305.pdf&data=02
> %7C01%7C
> +biwen.li%40nxp.com%7Cef95cc6d971c433d699808d8639c8b20%7C686ea1
> d3bc2b4c6
> +fa92cd99c5c301635%7C0%7C1%7C637368871279812461&sdata=1SaL
> 9ZOOTdEpMY
> +yXLQ%2F3KjbsHTgJ5UzK7o5ltsiBU5Y%3D&reserved=0
> + *
> + * Also supports the EMC2303 fan controller which has the same
> +functionality
> + * and register layout as EMC2305, but supports only up to 3 fans instead of
> 5.
> + *
> + * Also supports EMC2302 (up to 2 fans) and EMC2301 (1 fan) fan controller.
> + *
> + * 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program; if not, write to the Free Software
> + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
> + */
> +
> +/*
> + * TODO / IDEAS:
> + * - expose more of the configuration and features */
> +
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/slab.h>
> +#include <linux/jiffies.h>
> +#include <linux/i2c.h>
> +#include <linux/hwmon.h>
> +#include <linux/hwmon-sysfs.h>
> +#include <linux/err.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +
> +/*
> + * Addresses scanned.
> + * Listed in the same order as they appear in the EMC2305, EMC2303 data
> sheets.
> + *
> + * Note: these are the I2C adresses which are possible for EMC2305 and
> +EMC2303
> + * chips.
> + * The EMC2302 supports only 0x2e (EMC2302-1) and 0x2f (EMC2302-2).
> + * The EMC2301 supports only 0x2f.
> + */
> +static const unsigned short i2c_addresses[] = {
> + 0x2E,
> + 0x2F,
> + 0x2C,
> + 0x2D,
> + 0x4C,
> + 0x4D,
> + I2C_CLIENT_END
> +};
> +
> +/*
> + * global registers
> + */
> +enum {
> + REG_CONFIGURATION = 0x20,
> + REG_FAN_STATUS = 0x24,
> + REG_FAN_STALL_STATUS = 0x25,
> + REG_FAN_SPIN_STATUS = 0x26,
> + REG_DRIVE_FAIL_STATUS = 0x27,
> + REG_FAN_INTERRUPT_ENABLE = 0x29,
> + REG_PWM_POLARITY_CONFIG = 0x2a,
> + REG_PWM_OUTPUT_CONFIG = 0x2b,
> + REG_PWM_BASE_FREQ_1 = 0x2c,
> + REG_PWM_BASE_FREQ_2 = 0x2d,
> + REG_SOFTWARE_LOCK = 0xef,
> + REG_PRODUCT_FEATURES = 0xfc,
> + REG_PRODUCT_ID = 0xfd,
> + REG_MANUFACTURER_ID = 0xfe,
> + REG_REVISION = 0xff
> +};
> +
> +/*
> + * fan specific registers
> + */
> +enum {
> + REG_FAN_SETTING = 0x30,
> + REG_PWM_DIVIDE = 0x31,
> + REG_FAN_CONFIGURATION_1 = 0x32,
> + REG_FAN_CONFIGURATION_2 = 0x33,
> + REG_GAIN = 0x35,
> + REG_FAN_SPIN_UP_CONFIG = 0x36,
> + REG_FAN_MAX_STEP = 0x37,
> + REG_FAN_MINIMUM_DRIVE = 0x38,
> + REG_FAN_VALID_TACH_COUNT = 0x39,
> + REG_FAN_DRIVE_FAIL_BAND_LOW = 0x3a,
> + REG_FAN_DRIVE_FAIL_BAND_HIGH = 0x3b,
> + REG_TACH_TARGET_LOW = 0x3c,
> + REG_TACH_TARGET_HIGH = 0x3d,
> + REG_TACH_READ_HIGH = 0x3e,
> + REG_TACH_READ_LOW = 0x3f,
> +};
> +
> +#define SEL_FAN(fan, reg) (reg + fan * 0x10)
> +
> +/*
> + * Factor by equations [2] and [3] from data sheet; valid for fans
> +where the
> + * number of edges equals (poles * 2 + 1).
> + */
> +#define FAN_RPM_FACTOR 3932160
> +
> +struct emc2305_fan_data {
> + bool enabled;
> + bool rpm_control;
> + bool valid; /* registers are valid */
> + u8 poles;
> + u8 multiplier;
> + u16 tach;
> + u16 target;
> + unsigned long last_updated; /* in jiffies */
> +};
> +
> +struct emc2305_data {
> + struct i2c_client *client;
> + const struct attribute_group *groups[6];
> + struct mutex update_lock;
> + int fan_count; /* num of fan */
> + struct emc2305_fan_data fan[5];
> +};
> +
> +static int read_u8_from_i2c(struct i2c_client *client, u8 i2c_reg, u8
> +*output) {
> + int status = i2c_smbus_read_byte_data(client, i2c_reg);
> + if (status < 0) {
> + dev_warn(&client->dev, "reg 0x%02x, err %d\n",
> + i2c_reg, status);
> + } else {
> + *output = status;
> + }
> + return status;
> +}
> +
> +static void read_fan_from_i2c(struct i2c_client *client, u16 *output,
> + u8 hi_addr, u8 lo_addr)
> +{
> + u8 high_byte, lo_byte;
> +
> + if (read_u8_from_i2c(client, hi_addr, &high_byte) < 0)
> + return;
> +
> + if (read_u8_from_i2c(client, lo_addr, &lo_byte) < 0)
> + return;
> +
> + *output = ((u16)high_byte << 5) | (lo_byte >> 3); }
> +
> +static void write_fan_target_to_i2c(struct i2c_client *client, int fan,
> + u16 new_target)
> +{
> + const u8 lo_reg = SEL_FAN(fan, REG_TACH_TARGET_LOW);
> + const u8 hi_reg = SEL_FAN(fan, REG_TACH_TARGET_HIGH);
> + u8 high_byte = (new_target & 0x1fe0) >> 5;
> + u8 low_byte = (new_target & 0x001f) << 3;
> +
> + i2c_smbus_write_byte_data(client, lo_reg, low_byte);
> + i2c_smbus_write_byte_data(client, hi_reg, high_byte); }
> +
> +static void read_fan_config_from_i2c(struct i2c_client *client, int
> +fan_idx)
> +
> +{
> + struct emc2305_data *data = i2c_get_clientdata(client);
> + u8 conf1;
> +
> + if (read_u8_from_i2c(client, SEL_FAN(fan_idx,
> REG_FAN_CONFIGURATION_1),
> + &conf1) < 0)
> + return;
> +
> + data->fan[fan_idx].rpm_control = (conf1 & 0x80) != 0;
> + data->fan[fan_idx].multiplier = 1 << ((conf1 & 0x60) >> 5);
> + data->fan[fan_idx].poles = ((conf1 & 0x18) >> 3) + 1; }
> +
> +static void read_fan_data(struct i2c_client *client, int fan_idx) {
> + struct emc2305_data *data = i2c_get_clientdata(client);
> +
> + read_fan_from_i2c(client, &data->fan[fan_idx].target,
> + SEL_FAN(fan_idx, REG_TACH_TARGET_HIGH),
> + SEL_FAN(fan_idx, REG_TACH_TARGET_LOW));
> + read_fan_from_i2c(client, &data->fan[fan_idx].tach,
> + SEL_FAN(fan_idx, REG_TACH_READ_HIGH),
> + SEL_FAN(fan_idx, REG_TACH_READ_LOW)); }
> +
> +static struct emc2305_fan_data *
> +emc2305_update_fan(struct i2c_client *client, int fan_idx) {
> + struct emc2305_data *data = i2c_get_clientdata(client);
> + struct emc2305_fan_data *fan_data = &data->fan[fan_idx];
> +
> + mutex_lock(&data->update_lock);
> +
> + if (time_after(jiffies, fan_data->last_updated + HZ + HZ / 2)
> + || !fan_data->valid) {
> + read_fan_config_from_i2c(client, fan_idx);
> + read_fan_data(client, fan_idx);
> + fan_data->valid = true;
> + fan_data->last_updated = jiffies;
> + }
> +
> + mutex_unlock(&data->update_lock);
> + return fan_data;
> +}
> +
> +static struct emc2305_fan_data *
> +emc2305_update_device_fan(struct device *dev, struct device_attribute
> +*da) {
> + struct i2c_client *client = to_i2c_client(dev);
> + int fan_idx = to_sensor_dev_attr(da)->index;
> +
> + return emc2305_update_fan(client, fan_idx); }
> +
> +/*
> + * set/ config functions
> + */
> +
> +/*
> + * Note: we also update the fan target here, because its value is
> + * determined in part by the fan clock divider. This follows the
> +principle
> + * of least surprise; the user doesn't expect the fan target to change
> +just
> + * because the divider changed.
> + */
> +static int
> +emc2305_set_fan_div(struct i2c_client *client, int fan_idx, long
> +new_div) {
> + struct emc2305_data *data = i2c_get_clientdata(client);
> + struct emc2305_fan_data *fan = emc2305_update_fan(client, fan_idx);
> + const u8 reg_conf1 = SEL_FAN(fan_idx, REG_FAN_CONFIGURATION_1);
> + int new_range_bits, old_div = 8 / fan->multiplier;
> + int status = 0;
> +
> + if (new_div == old_div) /* No change */
> + return 0;
> +
> + switch (new_div) {
> + case 1:
> + new_range_bits = 3;
> + break;
> + case 2:
> + new_range_bits = 2;
> + break;
> + case 4:
> + new_range_bits = 1;
> + break;
> + case 8:
> + new_range_bits = 0;
> + break;
> + default:
> + return -EINVAL;
> + }
> +
> + mutex_lock(&data->update_lock);
> +
> + status = i2c_smbus_read_byte_data(client, reg_conf1);
> + if (status < 0) {
> + dev_dbg(&client->dev, "reg 0x%02x, err %d\n",
> + reg_conf1, status);
> + goto exit_unlock;
> + }
> + status &= 0x9F;
> + status |= (new_range_bits << 5);
> + status = i2c_smbus_write_byte_data(client, reg_conf1, status);
> + if (status < 0) {
> + goto exit_invalidate;
> + }
> +
> + fan->multiplier = 8 / new_div;
> +
> + /* update fan target if high byte is not disabled */
> + if ((fan->target & 0x1fe0) != 0x1fe0) {
> + u16 new_target = (fan->target * old_div) / new_div;
> + fan->target = min_t(u16, new_target, 0x1fff);
> + write_fan_target_to_i2c(client, fan_idx, fan->target);
> + }
> +
> +exit_invalidate:
> + /* invalidate fan data to force re-read from hardware */
> + fan->valid = false;
> +exit_unlock:
> + mutex_unlock(&data->update_lock);
> + return status;
> +}
> +
> +static int
> +emc2305_set_fan_target(struct i2c_client *client, int fan_idx, long
> +rpm_target) {
> + struct emc2305_data *data = i2c_get_clientdata(client);
> + struct emc2305_fan_data *fan = emc2305_update_fan(client, fan_idx);
> +
> + /*
> + * Datasheet states 16000 as maximum RPM target
> + * (table 2.2 and section 4.3)
> + */
> + if ((rpm_target < 0) || (rpm_target > 16000))
> + return -EINVAL;
> +
> + mutex_lock(&data->update_lock);
> +
> + if (rpm_target == 0)
> + fan->target = 0x1fff;
> + else
> + fan->target = clamp_val(
> + FAN_RPM_FACTOR * fan->multiplier / rpm_target,
> + 0, 0x1fff);
> +
> + write_fan_target_to_i2c(client, fan_idx, fan->target);
> +
> + mutex_unlock(&data->update_lock);
> + return 0;
> +}
> +
> +static int
> +emc2305_set_pwm_enable(struct i2c_client *client, int fan_idx, long
> +enable) {
> + struct emc2305_data *data = i2c_get_clientdata(client);
> + struct emc2305_fan_data *fan = emc2305_update_fan(client, fan_idx);
> + const u8 reg_fan_conf1 = SEL_FAN(fan_idx,
> REG_FAN_CONFIGURATION_1);
> + int status = 0;
> + u8 conf_reg;
> +
> + mutex_lock(&data->update_lock);
> + switch (enable) {
> + case 0:
> + fan->rpm_control = false;
> + break;
> + case 3:
> + fan->rpm_control = true;
> + break;
> + default:
> + status = -EINVAL;
> + goto exit_unlock;
> + }
> +
> + status = read_u8_from_i2c(client, reg_fan_conf1, &conf_reg);
> + if (status < 0)
> + goto exit_unlock;
> +
> + if (fan->rpm_control)
> + conf_reg |= 0x80;
> + else
> + conf_reg &= ~0x80;
> +
> + status = i2c_smbus_write_byte_data(client, reg_fan_conf1, conf_reg);
> +
> +exit_unlock:
> + mutex_unlock(&data->update_lock);
> + return status;
> +}
> +
> +static ssize_t
> +fan_input_show(struct device *dev, struct device_attribute *da, char
> +*buf) {
> + struct emc2305_fan_data *fan = emc2305_update_device_fan(dev, da);
> + int rpm = 0;
> +
> + if (fan->tach != 0)
> + rpm = (FAN_RPM_FACTOR * fan->multiplier) / fan->tach;
> + return sprintf(buf, "%d\n", rpm);
> +}
> +
> +static ssize_t
> +fan_fault_show(struct device *dev, struct device_attribute *da, char
> +*buf) {
> + struct emc2305_fan_data *fan = emc2305_update_device_fan(dev, da);
> +
> + return sprintf(buf, "%d\n", (fan->tach & 0x1fe0) == 0x1fe0); }
> +
> +static ssize_t
> +fan_div_show(struct device *dev, struct device_attribute *da, char
> +*buf) {
> + struct emc2305_fan_data *fan = emc2305_update_device_fan(dev, da);
> +
> + return sprintf(buf, "%d\n", 8 / fan->multiplier); }
> +
> +static ssize_t
> +fan_div_store(struct device *dev, struct device_attribute *da,
> + const char *buf, size_t count)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + int fan_idx = to_sensor_dev_attr(da)->index;
> + long new_div;
> + int status;
> +
> + status = kstrtol(buf, 10, &new_div);
> + if (status < 0)
> + return status;
> +
> + status = emc2305_set_fan_div(client, fan_idx, new_div);
> + if (status < 0)
> + return status;
> +
> + return count;
> +}
> +
> +static ssize_t
> +fan_target_show(struct device *dev, struct device_attribute *da, char
> +*buf) {
> + struct emc2305_fan_data *fan = emc2305_update_device_fan(dev, da);
> + int rpm = 0;
> +
> + /* high byte of 0xff indicates disabled so return 0 */
> + if ((fan->target != 0) && ((fan->target & 0x1fe0) != 0x1fe0))
> + rpm = FAN_RPM_FACTOR * fan->multiplier
> + / fan->target;
> +
> + return sprintf(buf, "%d\n", rpm);
> +}
> +
> +static ssize_t fan_target_store(struct device *dev, struct device_attribute *da,
> + const char *buf, size_t count) {
> + struct i2c_client *client = to_i2c_client(dev);
> + int fan_idx = to_sensor_dev_attr(da)->index;
> + long rpm_target;
> + int status;
> +
> + status = kstrtol(buf, 10, &rpm_target);
> + if (status < 0)
> + return status;
> +
> + status = emc2305_set_fan_target(client, fan_idx, rpm_target);
> + if (status < 0)
> + return status;
> +
> + return count;
> +}
> +
> +static ssize_t
> +pwm_enable_show(struct device *dev, struct device_attribute *da, char
> +*buf) {
> + struct emc2305_fan_data *fan = emc2305_update_device_fan(dev, da);
> + return sprintf(buf, "%d\n", fan->rpm_control ? 3 : 0); }
> +
> +static ssize_t pwm_enable_store(struct device *dev, struct device_attribute
> *da,
> + const char *buf, size_t count) {
> + struct i2c_client *client = to_i2c_client(dev);
> + int fan_idx = to_sensor_dev_attr(da)->index;
> + long new_value;
> + int status;
> +
> + status = kstrtol(buf, 10, &new_value);
> + if (status < 0)
> + return -EINVAL;
> + status = emc2305_set_pwm_enable(client, fan_idx, new_value);
> + return count;
> +}
> +
> +static SENSOR_DEVICE_ATTR_RO(fan1_input, fan_input, 0); static
> +SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0); static
> +SENSOR_DEVICE_ATTR_RW(fan1_target, fan_target, 0); static
> +SENSOR_DEVICE_ATTR_RO(fan1_fault, fan_fault, 0); static
> +SENSOR_DEVICE_ATTR_RO(fan2_input, fan_input, 1); static
> +SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1); static
> +SENSOR_DEVICE_ATTR_RW(fan2_target, fan_target, 1); static
> +SENSOR_DEVICE_ATTR_RO(fan2_fault, fan_fault, 1); static
> +SENSOR_DEVICE_ATTR_RO(fan3_input, fan_input, 2); static
> +SENSOR_DEVICE_ATTR_RW(fan3_div, fan_div, 2); static
> +SENSOR_DEVICE_ATTR_RW(fan3_target, fan_target, 2); static
> +SENSOR_DEVICE_ATTR_RO(fan3_fault, fan_fault, 2); static
> +SENSOR_DEVICE_ATTR_RO(fan4_input, fan_input, 3); static
> +SENSOR_DEVICE_ATTR_RW(fan4_div, fan_div, 3); static
> +SENSOR_DEVICE_ATTR_RW(fan4_target, fan_target, 3); static
> +SENSOR_DEVICE_ATTR_RO(fan4_fault, fan_fault, 3); static
> +SENSOR_DEVICE_ATTR_RO(fan5_input, fan_input, 4); static
> +SENSOR_DEVICE_ATTR_RW(fan5_div, fan_div, 4); static
> +SENSOR_DEVICE_ATTR_RW(fan5_target, fan_target, 4); static
> +SENSOR_DEVICE_ATTR_RO(fan5_fault, fan_fault, 4); static
> +SENSOR_DEVICE_ATTR_RW(pwm1, pwm_enable, 0); static
> +SENSOR_DEVICE_ATTR_RW(pwm2, pwm_enable, 1); static
> +SENSOR_DEVICE_ATTR_RW(pwm3, pwm_enable, 2); static
> +SENSOR_DEVICE_ATTR_RW(pwm4, pwm_enable, 3); static
> +SENSOR_DEVICE_ATTR_RW(pwm5, pwm_enable, 4);
> +
> +static struct attribute *emc2305_attributes_fan1[] = {
> + &sensor_dev_attr_fan1_input.dev_attr.attr,
> + &sensor_dev_attr_fan1_div.dev_attr.attr,
> + &sensor_dev_attr_fan1_target.dev_attr.attr,
> + &sensor_dev_attr_fan1_fault.dev_attr.attr,
> + &sensor_dev_attr_pwm1.dev_attr.attr,
> + NULL
> +};
> +
> +static struct attribute *emc2305_attributes_fan2[] = {
> + &sensor_dev_attr_fan2_input.dev_attr.attr,
> + &sensor_dev_attr_fan2_div.dev_attr.attr,
> + &sensor_dev_attr_fan2_target.dev_attr.attr,
> + &sensor_dev_attr_fan2_fault.dev_attr.attr,
> + &sensor_dev_attr_pwm2.dev_attr.attr,
> + NULL
> +};
> +
> +static struct attribute *emc2305_attributes_fan3[] = {
> + &sensor_dev_attr_fan3_input.dev_attr.attr,
> + &sensor_dev_attr_fan3_div.dev_attr.attr,
> + &sensor_dev_attr_fan3_target.dev_attr.attr,
> + &sensor_dev_attr_fan3_fault.dev_attr.attr,
> + &sensor_dev_attr_pwm3.dev_attr.attr,
> + NULL
> +};
> +
> +static struct attribute *emc2305_attributes_fan4[] = {
> + &sensor_dev_attr_fan4_input.dev_attr.attr,
> + &sensor_dev_attr_fan4_div.dev_attr.attr,
> + &sensor_dev_attr_fan4_target.dev_attr.attr,
> + &sensor_dev_attr_fan4_fault.dev_attr.attr,
> + &sensor_dev_attr_pwm4.dev_attr.attr,
> + NULL
> +};
> +
> +static struct attribute *emc2305_attributes_fan5[] = {
> + &sensor_dev_attr_fan5_input.dev_attr.attr,
> + &sensor_dev_attr_fan5_div.dev_attr.attr,
> + &sensor_dev_attr_fan5_target.dev_attr.attr,
> + &sensor_dev_attr_fan5_fault.dev_attr.attr,
> + &sensor_dev_attr_pwm5.dev_attr.attr,
> + NULL
> +};
> +
> +static const struct attribute_group emc2305_fan1_group = {
> + .attrs = emc2305_attributes_fan1,
> +};
> +
> +static const struct attribute_group emc2305_fan2_group = {
> + .attrs = emc2305_attributes_fan2,
> +};
> +
> +static const struct attribute_group emc2305_fan3_group = {
> + .attrs = emc2305_attributes_fan3,
> +};
> +
> +static const struct attribute_group emc2305_fan4_group = {
> + .attrs = emc2305_attributes_fan4,
> +};
> +
> +static const struct attribute_group emc2305_fan5_group = {
> + .attrs = emc2305_attributes_fan5,
> +};
> +
> +/*
> + * driver interface
> + */
> +static int
> +emc2305_probe(struct i2c_client *client, const struct i2c_device_id
> +*id) {
> + struct emc2305_data *data;
> + struct device *hwmon_dev;
> + int status, idx = 0;
> +
> + if (!i2c_check_functionality(client->adapter,
> I2C_FUNC_SMBUS_BYTE_DATA))
> + return -EIO;
> +
> + data = devm_kzalloc(&client->dev, sizeof(struct emc2305_data),
> GFP_KERNEL);
> + if (!data)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(client, data);
> + data->client = client;
> + mutex_init(&data->update_lock);
> +
> + status = i2c_smbus_read_byte_data(client, REG_PRODUCT_ID);
> + switch (status) {
> + case 0x34: /* EMC2305 */
> + data->fan_count = 5;
> + break;
> + case 0x35: /* EMC2303 */
> + data->fan_count = 3;
> + break;
> + case 0x36: /* EMC2302 */
> + data->fan_count = 2;
> + break;
> + case 0x37: /* EMC2301 */
> + data->fan_count = 1;
> + break;
> + default:
> + if (status < 0)
> + dev_err(&client->dev, "Failed to read reg REG_PRODUCT_ID,
> status = %d\n", status);
> + else
> + dev_err(&client->dev, "Unknown device, status = %d\n", status);
> + return status;
> + }
> +
> + /* sysfs hooks */
> + data->groups[idx++] = &emc2305_fan1_group;
> + if (data->fan_count >= 2)
> + data->groups[idx++] = &emc2305_fan2_group;
> + if (data->fan_count >= 3) {
> + data->groups[idx++] = &emc2305_fan3_group;
> + }
> + if (data->fan_count == 5) {
> + data->groups[idx++] = &emc2305_fan4_group;
> + data->groups[idx++] = &emc2305_fan5_group;
> + }
> +
> + hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
> + client->name, data,
> + data->groups);
> + if (IS_ERR(hwmon_dev))
> + return PTR_ERR(hwmon_dev);
> +
> + dev_info(&client->dev, "pwm fan controller: '%s'\n",
> + client->name);
> +
> + return 0;
> +}
> +
> +static const struct i2c_device_id emc2305_ids[] = {
> + { "emc2301", 0 },
> + { "emc2302", 0 },
> + { "emc2303", 0 },
> + { "emc2305", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, emc2305_ids);
> +
> +/* Return 0 if detection is successful, -ENODEV otherwise */ static int
> +emc2305_detect(struct i2c_client *new_client, struct i2c_board_info
> +*info) {
> + struct i2c_adapter *adapter = new_client->adapter;
> + int manufacturer, product;
> +
> + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
> + return -ENODEV;
> +
> + manufacturer =
> + i2c_smbus_read_byte_data(new_client, REG_MANUFACTURER_ID);
> + if (manufacturer != 0x5D)
> + return -ENODEV;
> +
> + product = i2c_smbus_read_byte_data(new_client, REG_PRODUCT_ID);
> +
> + switch (product) {
> + case 0x34:
> + strlcpy(info->type, "emc2305", I2C_NAME_SIZE);
> + break;
> + case 0x35:
> + strlcpy(info->type, "emc2303", I2C_NAME_SIZE);
> + break;
> + case 0x36:
> + strlcpy(info->type, "emc2302", I2C_NAME_SIZE);
> + break;
> + case 0x37:
> + strlcpy(info->type, "emc2301", I2C_NAME_SIZE);
> + break;
> + default:
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static struct i2c_driver emc2305_driver = {
> + .class = I2C_CLASS_HWMON,
> + .driver = {
> + .name = "emc2305",
> + },
> + .probe = emc2305_probe,
> + .id_table = emc2305_ids,
> + .detect = emc2305_detect,
> + .address_list = i2c_addresses,
> +};
> +
> +module_i2c_driver(emc2305_driver);
> +
> +MODULE_AUTHOR("Reinhard Pfau <pfau@gdsys>, Biwen Li
> +<biwen.li@xxxxxxx>\n"); MODULE_DESCRIPTION("SMSC EMC2305 hwmon
> +driver"); MODULE_LICENSE("GPL");
> --
> 2.17.1