diff options
| -rw-r--r-- | Documentation/devicetree/bindings/hwmon/g762.txt | 47 | ||||
| -rw-r--r-- | Documentation/hwmon/g762 | 65 | ||||
| -rw-r--r-- | drivers/hwmon/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/hwmon/Makefile | 1 | ||||
| -rw-r--r-- | drivers/hwmon/g762.c | 1149 | ||||
| -rw-r--r-- | include/linux/platform_data/g762.h | 37 |
6 files changed, 1309 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/hwmon/g762.txt b/Documentation/devicetree/bindings/hwmon/g762.txt new file mode 100644 index 000000000000..25cc6d8ee575 --- /dev/null +++ b/Documentation/devicetree/bindings/hwmon/g762.txt @@ -0,0 +1,47 @@ +GMT G762/G763 PWM Fan controller + +Required node properties: + + - "compatible": must be either "gmt,g762" or "gmt,g763" + - "reg": I2C bus address of the device + - "clocks": a fixed clock providing input clock frequency + on CLK pin of the chip. + +Optional properties: + + - "fan_startv": fan startup voltage. Accepted values are 0, 1, 2 and 3. + The higher the more. + + - "pwm_polarity": pwm polarity. Accepted values are 0 (positive duty) + and 1 (negative duty). + + - "fan_gear_mode": fan gear mode. Supported values are 0, 1 and 2. + +If an optional property is not set in .dts file, then current value is kept +unmodified (e.g. u-boot installed value). + +Additional information on operational parameters for the device is available +in Documentation/hwmon/g762. A detailed datasheet for the device is available +at http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf. + +Example g762 node: + + clocks { + #address-cells = <1>; + #size-cells = <0>; + + g762_clk: fixedclk { + compatible = "fixed-clock"; + #clock-cells = <0>; + clock-frequency = <8192>; + } + } + + g762: g762@3e { + compatible = "gmt,g762"; + reg = <0x3e>; + clocks = <&g762_clk> + fan_gear_mode = <0>; /* chip default */ + fan_startv = <1>; /* chip default */ + pwm_polarity = <0>; /* chip default */ + }; diff --git a/Documentation/hwmon/g762 b/Documentation/hwmon/g762 new file mode 100644 index 000000000000..923db9c5b5bc --- /dev/null +++ b/Documentation/hwmon/g762 @@ -0,0 +1,65 @@ +Kernel driver g762 +================== + +The GMT G762 Fan Speed PWM Controller is connected directly to a fan +and performs closed-loop or open-loop control of the fan speed. Two +modes - PWM or DC - are supported by the device. + +For additional information, a detailed datasheet is available at +http://natisbad.org/NAS/ref/GMT_EDS-762_763-080710-0.2.pdf. sysfs +bindings are described in Documentation/hwmon/sysfs-interface. + +The following entries are available to the user in a subdirectory of +/sys/bus/i2c/drivers/g762/ to control the operation of the device. +This can be done manually using the following entries but is usually +done via a userland daemon like fancontrol. + +Note that those entries do not provide ways to setup the specific +hardware characteristics of the system (reference clock, pulses per +fan revolution, ...); Those can be modified via devicetree bindings +documented in Documentation/devicetree/bindings/hwmon/g762.txt or +using a specific platform_data structure in board initialization +file (see include/linux/platform_data/g762.h). + + fan1_target: set desired fan speed. This only makes sense in closed-loop + fan speed control (i.e. when pwm1_enable is set to 2). + + fan1_input: provide current fan rotation value in RPM as reported by + the fan to the device. + + fan1_div: fan clock divisor. Supported value are 1, 2, 4 and 8. + + fan1_pulses: number of pulses per fan revolution. Supported values + are 2 and 4. + + fan1_fault: reports fan failure, i.e. no transition on fan gear pin for + about 0.7s (if the fan is not voluntarily set off). + + fan1_alarm: in closed-loop control mode, if fan RPM value is 25% out + of the programmed value for over 6 seconds 'fan1_alarm' is + set to 1. + + pwm1_enable: set current fan speed control mode i.e. 1 for manual fan + speed control (open-loop) via pwm1 described below, 2 for + automatic fan speed control (closed-loop) via fan1_target + above. + + pwm1_mode: set or get fan driving mode: 1 for PWM mode, 0 for DC mode. + + pwm1: get or set PWM fan control value in open-loop mode. This is an + integer value between 0 and 255. 0 stops the fan, 255 makes + it run at full speed. + +Both in PWM mode ('pwm1_mode' set to 1) and DC mode ('pwm1_mode' set to 0), +when current fan speed control mode is open-loop ('pwm1_enable' set to 1), +the fan speed is programmed by setting a value between 0 and 255 via 'pwm1' +entry (0 stops the fan, 255 makes it run at full speed). In closed-loop mode +('pwm1_enable' set to 2), the expected rotation speed in RPM can be passed to +the chip via 'fan1_target'. In closed-loop mode, the target speed is compared +with current speed (available via 'fan1_input') by the device and a feedback +is performed to match that target value. The fan speed value is computed +based on the parameters associated with the physical characteristics of the +system: a reference clock source frequency, a number of pulses per fan +revolution, etc. + +Note that the driver will update its values at most once per second. diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig index 683c769a8fca..e989f7fd645b 100644 --- a/drivers/hwmon/Kconfig +++ b/drivers/hwmon/Kconfig @@ -461,6 +461,16 @@ config SENSORS_G760A This driver can also be built as a module. If so, the module will be called g760a. +config SENSORS_G762 + tristate "GMT G762 and G763" + depends on I2C + help + If you say yes here you get support for Global Mixed-mode + Technology Inc G762 and G763 fan speed PWM controller chips. + + This driver can also be built as a module. If so, the module + will be called g762. + config SENSORS_GL518SM tristate "Genesys Logic GL518SM" depends on I2C diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile index d17d3e64f9f4..4f0fb5235f42 100644 --- a/drivers/hwmon/Makefile +++ b/drivers/hwmon/Makefile @@ -60,6 +60,7 @@ obj-$(CONFIG_SENSORS_F75375S) += f75375s.o obj-$(CONFIG_SENSORS_FAM15H_POWER) += fam15h_power.o obj-$(CONFIG_SENSORS_FSCHMD) += fschmd.o obj-$(CONFIG_SENSORS_G760A) += g760a.o +obj-$(CONFIG_SENSORS_G762) += g762.o obj-$(CONFIG_SENSORS_GL518SM) += gl518sm.o obj-$(CONFIG_SENSORS_GL520SM) += gl520sm.o obj-$(CONFIG_SENSORS_GPIO_FAN) += gpio-fan.o diff --git a/drivers/hwmon/g762.c b/drivers/hwmon/g762.c new file mode 100644 index 000000000000..73adf01b0ef2 --- /dev/null +++ b/drivers/hwmon/g762.c @@ -0,0 +1,1149 @@ +/* + * g762 - Driver for the Global Mixed-mode Technology Inc. fan speed + * PWM controller chips from G762 family, i.e. G762 and G763 + * + * Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org> + * + * This work is based on a basic version for 2.6.31 kernel developed + * by Olivier Mouchet for LaCie. Updates and correction have been + * performed to run on recent kernels. Additional features, like the + * ability to configure various characteristics via .dts file or + * board init file have been added. Detailed datasheet on which this + * development is based is available here: + * + * http://natisbad.org/NAS/refs/GMT_EDS-762_763-080710-0.2.pdf + * + * Headers from previous developments have been kept below: + * + * Copyright (c) 2009 LaCie + * + * Author: Olivier Mouchet <olivier.mouchet@gmail.com> + * + * based on g760a code written by Herbert Valerio Riedel <hvr@gnu.org> + * Copyright (C) 2007 Herbert Valerio Riedel <hvr@gnu.org> + * + * g762: minimal datasheet available at: + * http://www.gmt.com.tw/product/datasheet/EDS-762_3.pdf + * + * 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. + */ + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/init.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/kernel.h> +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_data/g762.h> + +#define DRVNAME "g762" + +static const struct i2c_device_id g762_id[] = { + { "g762", 0 }, + { "g763", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, g762_id); + +enum g762_regs { + G762_REG_SET_CNT = 0x00, + G762_REG_ACT_CNT = 0x01, + G762_REG_FAN_STA = 0x02, + G762_REG_SET_OUT = 0x03, + G762_REG_FAN_CMD1 = 0x04, + G762_REG_FAN_CMD2 = 0x05, +}; + +/* Config register bits */ +#define G762_REG_FAN_CMD1_DET_FAN_FAIL 0x80 /* enable fan_fail signal */ +#define G762_REG_FAN_CMD1_DET_FAN_OOC 0x40 /* enable fan_out_of_control */ +#define G762_REG_FAN_CMD1_OUT_MODE 0x20 /* out mode: PWM or DC */ +#define G762_REG_FAN_CMD1_FAN_MODE 0x10 /* fan mode: closed/open-loop */ +#define G762_REG_FAN_CMD1_CLK_DIV_ID1 0x08 /* clock divisor value */ +#define G762_REG_FAN_CMD1_CLK_DIV_ID0 0x04 +#define G762_REG_FAN_CMD1_PWM_POLARITY 0x02 /* PWM polarity */ +#define G762_REG_FAN_CMD1_PULSE_PER_REV 0x01 /* pulse per fan revolution */ + +#define G762_REG_FAN_CMD2_GEAR_MODE_1 0x08 /* fan gear mode */ +#define G762_REG_FAN_CMD2_GEAR_MODE_0 0x04 +#define G762_REG_FAN_CMD2_FAN_STARTV_1 0x02 /* fan startup voltage */ +#define G762_REG_FAN_CMD2_FAN_STARTV_0 0x01 + +#define G762_REG_FAN_STA_FAIL 0x02 /* fan fail */ +#define G762_REG_FAN_STA_OOC 0x01 /* fan out of control */ + +/* Config register values */ +#define G762_OUT_MODE_PWM 1 +#define G762_OUT_MODE_DC 0 + +#define G762_FAN_MODE_CLOSED_LOOP 2 +#define G762_FAN_MODE_OPEN_LOOP 1 + +#define G762_PWM_POLARITY_NEGATIVE 1 +#define G762_PWM_POLARITY_POSITIVE 0 + +/* Register data is read (and cached) at most once per second. */ +#define G762_UPDATE_INTERVAL HZ + +/* + * Extract pulse count per fan revolution value (2 or 4) from given + * FAN_CMD1 register value. + */ +#define G762_PULSE_FROM_REG(reg) \ + ((((reg) & G762_REG_FAN_CMD1_PULSE_PER_REV) + 1) << 1) + +/* + * Extract fan clock divisor (1, 2, 4 or 8) from given FAN_CMD1 + * register value. + */ +#define G762_CLKDIV_FROM_REG(reg) \ + (1 << (((reg) & (G762_REG_FAN_CMD1_CLK_DIV_ID0 | \ + G762_REG_FAN_CMD1_CLK_DIV_ID1)) >> 2)) + +/* + * Extract fan gear mode multiplier value (0, 2 or 4) from given + * FAN_CMD2 register value. + */ +#define G762_GEARMULT_FROM_REG(reg) \ + (1 << (((reg) & (G762_REG_FAN_CMD2_GEAR_MODE_0 | \ + G762_REG_FAN_CMD2_GEAR_MODE_1)) >> 2)) + +struct g762_data { + struct i2c_client *client; + struct device *hwmon_dev; + struct clk *clk; + + /* update mutex */ + struct mutex update_lock; + + /* board specific parameters. */ + u32 clk_freq; + + /* g762 register cache */ + bool valid; + unsigned long last_updated; /* in jiffies */ + + u8 set_cnt; /* controls fan rotation speed in closed-loop mode */ + u8 act_cnt; /* provides access to current fan RPM value */ + u8 fan_sta; /* bit 0: set when actual fan speed is more than + * 25% outside requested fan speed + * bit 1: set when no transition occurs on fan + * pin for 0.7s + */ + u8 set_out; /* controls fan rotation speed in open-loop mode */ + u8 fan_cmd1; /* 0: FG_PLS_ID0 FG pulses count per revolution + * 0: 2 counts per revolution + * 1: 4 counts per revolution + * 1: PWM_POLARITY 1: negative_duty + * 0: positive_duty + * 2,3: [FG_CLOCK_ID0, FG_CLK_ID1] + * 00: Divide fan clock by 1 + * 01: Divide fan clock by 2 + * 10: Divide fan clock by 4 + * 11: Divide fan clock by 8 + * 4: FAN_MODE 1:closed-loop, 0:open-loop + * 5: OUT_MODE 1:PWM, 0:DC + * 6: DET_FAN_OOC enable "fan ooc" status + * 7: DET_FAN_FAIL enable "fan fail" status + */ + u8 fan_cmd2; /* 0,1: FAN_STARTV 0,1,2,3 -> 0,32,64,96 dac_code + * 2,3: FG_GEAR_MODE + * 00: multiplier = 1 + * 01: multiplier = 2 + * 10: multiplier = 4 + * 4: Mask ALERT# (g763 only) + */ +}; + +/* + * Convert count value from fan controller register (FAN_SET_CNT) into fan + * speed RPM value. Note that the datasheet documents a basic formula; + * influence of additional parameters (fan clock divisor, fan gear mode) + * have been infered from examples in the datasheet and tests. + */ +static inline unsigned int rpm_from_cnt(u8 cnt, u32 clk_freq, u16 p, + u8 clk_div, u8 gear_mult) +{ + if (cnt == 0xff) /* setting cnt to 255 stops the fan */ + return 0; + + return (clk_freq * 30 * gear_mult) / ((cnt ? cnt : 1) * p * clk_div); +} + +/* + * Convert fan RPM value from sysfs into count value for fan controller + * register (FAN_SET_CNT). + */ +static inline unsigned char cnt_from_rpm(u32 rpm, u32 clk_freq, u16 p, + u8 clk_div, u8 gear_mult) +{ + if (!rpm) /* to stop the fan, set cnt to 255 */ + return 0xff; + + return clamp_val(((clk_freq * 30 * gear_mult) / (rpm * p * clk_div)), + 0, 255); +} + +/* helper to grab and cache data, at most one time per second */ +static struct g762_data *g762_update_client(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = i2c_get_clientdata(client); + int ret = 0; + + mutex_lock(&data->update_lock); + if (time_before(jiffies, data->last_updated + G762_UPDATE_INTERVAL) && + likely(data->valid)) + goto out; + + ret = i2c_smbus_read_byte_data(client, G762_REG_SET_CNT); + if (ret < 0) + goto out; + data->set_cnt = ret; + + ret = i2c_smbus_read_byte_data(client, G762_REG_ACT_CNT); + if (ret < 0) + goto out; + data->act_cnt = ret; + + ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_STA); + if (ret < 0) + goto out; + data->fan_sta = ret; + + ret = i2c_smbus_read_byte_data(client, G762_REG_SET_OUT); + if (ret < 0) + goto out; + data->set_out = ret; + + ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD1); + if (ret < 0) + goto out; + data->fan_cmd1 = ret; + + ret = i2c_smbus_read_byte_data(client, G762_REG_FAN_CMD2); + if (ret < 0) + goto out; + data->fan_cmd2 = ret; + + data->last_updated = jiffies; + data->valid = true; + out: + mutex_unlock(&data->update_lock); + + if (ret < 0) /* upon error, encode it in return value */ + data = ERR_PTR(ret); + + return data; +} + +/* helpers for writing hardware parameters */ + +/* + * Set input clock frequency received on CLK pin of the chip. Accepted values + * are between 0 and 0xffffff. If zero is given, then default frequency + * (32,768Hz) is used. Note that clock frequency is a characteristic of the + * system but an internal parameter, i.e. value is not passed to the device. + */ +static int do_set_clk_freq(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = i2c_get_clientdata(client); + + if (val > 0xffffff) + return -EINVAL; + if (!val) + val = 32768; + + data->clk_freq = val; + + return 0; +} + +/* Set pwm mode. Accepts either 0 (PWM mode) or 1 (DC mode) */ +static int do_set_pwm_mode(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case G762_OUT_MODE_PWM: + data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE; + break; + case G762_OUT_MODE_DC: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set fan clock divisor. Accepts either 1, 2, 4 or 8. */ +static int do_set_fan_div(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case 1: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; + break; + case 2: + data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID1; + break; + case 4: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_CLK_DIV_ID0; + data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; + break; + case 8: + data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID0; + data->fan_cmd1 |= G762_REG_FAN_CMD1_CLK_DIV_ID1; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set fan gear mode. Accepts either 0, 1 or 2. */ +static int do_set_fan_gear_mode(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case 0: + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; + break; + case 1: + data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_0; + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_1; + break; + case 2: + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_GEAR_MODE_0; + data->fan_cmd2 |= G762_REG_FAN_CMD2_GEAR_MODE_1; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD2, + data->fan_cmd2); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set number of fan pulses per revolution. Accepts either 2 or 4. */ +static int do_set_fan_pulses(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case 2: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PULSE_PER_REV; + break; + case 4: + data->fan_cmd1 |= G762_REG_FAN_CMD1_PULSE_PER_REV; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set fan mode. Accepts either 1 (open-loop) or 2 (closed-loop). */ +static int do_set_pwm_enable(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case G762_FAN_MODE_CLOSED_LOOP: + data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE; + break; + case G762_FAN_MODE_OPEN_LOOP: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE; + /* + * BUG FIX: if SET_CNT register value is 255 then, for some + * unknown reason, fan will not rotate as expected, no matter + * the value of SET_OUT (to be specific, this seems to happen + * only in PWM mode). To workaround this bug, we give SET_CNT + * value of 254 if it is 255 when switching to open-loop. + */ + if (data->set_cnt == 0xff) + i2c_smbus_write_byte_data(client, G762_REG_SET_CNT, + 254); + break; + default: + ret = -EINVAL; + goto out; + } + + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set PWM polarity. Accepts either 0 (positive duty) or 1 (negative duty) */ +static int do_set_pwm_polarity(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case G762_PWM_POLARITY_POSITIVE: + data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY; + break; + case G762_PWM_POLARITY_NEGATIVE: + data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* + * Set pwm value. Accepts values between 0 (stops the fan) and + * 255 (full speed). This only makes sense in open-loop mode. + */ +static int do_set_pwm(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = i2c_get_clientdata(client); + int ret; + + if (val > 255) + return -EINVAL; + + mutex_lock(&data->update_lock); + ret = i2c_smbus_write_byte_data(client, G762_REG_SET_OUT, val); + data->valid = false; + mutex_unlock(&data->update_lock); + + return ret; +} + +/* + * Set fan RPM value. Can be called both in closed and open-loop mode + * but effect will only be seen after closed-loop mode is configured. + */ +static int do_set_fan_target(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + data->set_cnt = cnt_from_rpm(val, data->clk_freq, + G762_PULSE_FROM_REG(data->fan_cmd1), + G762_CLKDIV_FROM_REG(data->fan_cmd1), + G762_GEARMULT_FROM_REG(data->fan_cmd2)); + ret = i2c_smbus_write_byte_data(client, G762_REG_SET_CNT, + data->set_cnt); + data->valid = false; + mutex_unlock(&data->update_lock); + + return ret; +} + +/* Set fan startup voltage. Accepted values are either 0, 1, 2 or 3. */ +static int do_set_fan_startv(struct device *dev, unsigned long val) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + int ret; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + switch (val) { + case 0: + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; + break; + case 1: + data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1; + break; + case 2: + data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0; + data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; + break; + case 3: + data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0; + data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1; + break; + default: + ret = -EINVAL; + goto out; + } + ret = i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD2, + data->fan_cmd2); + data->valid = false; + out: + mutex_unlock(&data->update_lock); + + return ret; +} + +/* + * Helper to import hardware characteristics from .dts file and push + * those to the chip. + */ + +#ifdef CONFIG_OF +static struct of_device_id g762_dt_match[] = { + { .compatible = "gmt,g762" }, + { .compatible = "gmt,g763" }, + { }, +}; + +/* + * Grab clock (a required property), enable it, get (fixed) clock frequency + * and store it. Note: upon success, clock has been prepared and enabled; it + * must later be unprepared and disabled (e.g. during module unloading) by a + * call to g762_of_clock_disable(). Note that a reference to clock is kept + * in our private data structure to be used in this function. + */ +static int g762_of_clock_enable(struct i2c_client *client) +{ + struct g762_data *data; + unsigned long clk_freq; + struct clk *clk; + int ret; + + if (!client->dev.of_node) + return 0; + + clk = of_clk_get(client->dev.of_node, 0); + if (IS_ERR(clk)) { + dev_err(&client->dev, "failed to get clock\n"); + return PTR_ERR(clk); + } + + ret = clk_prepare_enable(clk); + if (ret) { + dev_err(&client->dev, "failed to enable clock\n"); + goto clk_put; + } + + clk_freq = clk_get_rate(clk); + ret = do_set_clk_freq(&client->dev, clk_freq); + if (ret) { + dev_err(&client->dev, "invalid clock freq %lu\n", clk_freq); + goto clk_unprep; + } + + data = i2c_get_clientdata(client); + data->clk = clk; + + return 0; + + clk_unprep: + clk_disable_unprepare(clk); + + clk_put: + clk_put(clk); + + return ret; +} + +static void g762_of_clock_disable(struct i2c_client *client) +{ + struct g762_data *data = i2c_get_clientdata(client); + + if (!data->clk) + return; + + clk_disable_unprepare(data->clk); + clk_put(data->clk); +} + +static int g762_of_prop_import_one(struct i2c_client *client, + const char *pname, + int (*psetter)(struct device *dev, + unsigned long val)) +{ + const __be32 *prop; + int len, ret; + u32 pval; + + prop = of_get_property(client->dev.of_node, pname, &len); + if (!prop || len != sizeof(u32)) + return 0; + + pval = be32_to_cpu(prop[0]); + dev_dbg(&client->dev, "found %s (%d)\n", pname, pval); + ret = (*psetter)(&client->dev, pval); + if (ret) + dev_err(&client->dev, "unable to set %s (%d)\n", pname, pval); + + return ret; +} + +static int g762_of_prop_import(struct i2c_client *client) +{ + int ret; + + if (!client->dev.of_node) + return 0; + + ret = g762_of_prop_import_one(client, "fan_gear_mode", + do_set_fan_gear_mode); + if (ret) + return ret; + + ret = g762_of_prop_import_one(client, "pwm_polarity", + do_set_pwm_polarity); + if (ret) + return ret; + + return g762_of_prop_import_one(client, "fan_startv", + do_set_fan_startv); +} + +#else +static int g762_of_prop_import(struct i2c_client *client) +{ + return 0; +} + +static int g762_of_clock_enable(struct i2c_client *client) +{ + return 0; +} + +static void g762_of_clock_disable(struct i2c_client *client) { } +#endif + +/* + * Helper to import hardware characteristics from .dts file and push + * those to the chip. + */ + +static int g762_pdata_prop_import(struct i2c_client *client) +{ + struct g762_platform_data *pdata = client->dev.platform_data; + int ret; + + if (!pdata) + return 0; + + ret = do_set_fan_gear_mode(&client->dev, pdata->fan_gear_mode); + if (ret) + return ret; + + ret = do_set_pwm_polarity(&client->dev, pdata->pwm_polarity); + if (ret) + return ret; + + ret = do_set_fan_startv(&client->dev, pdata->fan_startv); + if (ret) + return ret; + + return do_set_clk_freq(&client->dev, pdata->clk_freq); +} + +/* + * sysfs attributes + */ + +/* + * Read function for fan1_input sysfs file. Return current fan RPM value, or + * 0 if fan is out of control. + */ +static ssize_t get_fan_rpm(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + unsigned int rpm = 0; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + /* reverse logic: fan out of control reporting is enabled low */ + if (data->fan_sta & G762_REG_FAN_STA_OOC) { + rpm = rpm_from_cnt(data->act_cnt, data->clk_freq, + G762_PULSE_FROM_REG(data->fan_cmd1), + G762_CLKDIV_FROM_REG(data->fan_cmd1), + G762_GEARMULT_FROM_REG(data->fan_cmd2)); + } + mutex_unlock(&data->update_lock); + + return sprintf(buf, "%u\n", rpm); +} + +/* + * Read and write functions for pwm1_mode sysfs file. Get and set fan speed + * control mode i.e. PWM (1) or DC (0). + */ +static ssize_t get_pwm_mode(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", + !!(data->fan_cmd1 & G762_REG_FAN_CMD1_OUT_MODE)); +} + +static ssize_t set_pwm_mode(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_pwm_mode(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* + * Read and write functions for fan1_div sysfs file. Get and set fan + * controller prescaler value + */ +static ssize_t get_fan_div(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", G762_CLKDIV_FROM_REG(data->fan_cmd1)); +} + +static ssize_t set_fan_div(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_fan_div(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* + * Read and write functions for fan1_pulses sysfs file. Get and set number + * of tachometer pulses per fan revolution. + */ +static ssize_t get_fan_pulses(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", G762_PULSE_FROM_REG(data->fan_cmd1)); +} + +static ssize_t set_fan_pulses(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_fan_pulses(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* + * Read and write functions for pwm1_enable. Get and set fan speed control mode + * (i.e. closed or open-loop). + * + * Following documentation about hwmon's sysfs interface, a pwm1_enable node + * should accept followings: + * + * 0 : no fan speed control (i.e. fan at full speed) + * 1 : manual fan speed control enabled (use pwm[1-*]) (open-loop) + * 2+: automatic fan speed control enabled (use fan[1-*]_target) (closed-loop) + * + * but we do not accept 0 as this mode is not natively supported by the chip + * and it is not emulated by g762 driver. -EINVAL is returned in this case. + */ +static ssize_t get_pwm_enable(struct device *dev, + struct device_attribute *da, char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", + (!!(data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE)) + 1); +} + +static ssize_t set_pwm_enable(struct device *dev, + struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_pwm_enable(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* + * Read and write functions for pwm1 sysfs file. Get and set pwm value + * (which affects fan speed) in open-loop mode. 0 stops the fan and 255 + * makes it run at full speed. + */ +static ssize_t get_pwm(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%d\n", data->set_out); +} + +static ssize_t set_pwm(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_pwm(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* + * Read and write function for fan1_target sysfs file. Get/set the fan speed in + * closed-loop mode. Speed is given as a RPM value; then the chip will regulate + * the fan speed using pulses from fan tachometer. + * + * Refer to rpm_from_cnt() implementation above to get info about count number + * calculation. + * + * Also note that due to rounding errors it is possible that you don't read + * back exactly the value you have set. + */ +static ssize_t get_fan_target(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + unsigned int rpm; + + if (IS_ERR(data)) + return PTR_ERR(data); + + mutex_lock(&data->update_lock); + rpm = rpm_from_cnt(data->set_cnt, data->clk_freq, + G762_PULSE_FROM_REG(data->fan_cmd1), + G762_CLKDIV_FROM_REG(data->fan_cmd1), + G762_GEARMULT_FROM_REG(data->fan_cmd2)); + mutex_unlock(&data->update_lock); + + return sprintf(buf, "%u\n", rpm); +} + +static ssize_t set_fan_target(struct device *dev, struct device_attribute *da, + const char *buf, size_t count) +{ + unsigned long val; + int ret; + + if (kstrtoul(buf, 10, &val)) + return -EINVAL; + + ret = do_set_fan_target(dev, val); + if (ret < 0) + return ret; + + return count; +} + +/* read function for fan1_fault sysfs file. */ +static ssize_t get_fan_failure(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%u\n", !!(data->fan_sta & G762_REG_FAN_STA_FAIL)); +} + +/* + * read function for fan1_alarm sysfs file. Note that OOC condition is + * enabled low + */ +static ssize_t get_fan_ooc(struct device *dev, struct device_attribute *da, + char *buf) +{ + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + return sprintf(buf, "%u\n", !(data->fan_sta & G762_REG_FAN_STA_OOC)); +} + +static DEVICE_ATTR(pwm1, S_IWUSR | S_IRUGO, get_pwm, set_pwm); +static DEVICE_ATTR(pwm1_mode, S_IWUSR | S_IRUGO, get_pwm_mode, set_pwm_mode); +static DEVICE_ATTR(pwm1_enable, S_IWUSR | S_IRUGO, + get_pwm_enable, set_pwm_enable); +static DEVICE_ATTR(fan1_input, S_IRUGO, get_fan_rpm, NULL); +static DEVICE_ATTR(fan1_alarm, S_IRUGO, get_fan_ooc, NULL); +static DEVICE_ATTR(fan1_fault, S_IRUGO, get_fan_failure, NULL); +static DEVICE_ATTR(fan1_target, S_IWUSR | S_IRUGO, + get_fan_target, set_fan_target); +static DEVICE_ATTR(fan1_div, S_IWUSR | S_IRUGO, get_fan_div, set_fan_div); +static DEVICE_ATTR(fan1_pulses, S_IWUSR | S_IRUGO, + get_fan_pulses, set_fan_pulses); + +/* Driver data */ +static struct attribute *g762_attributes[] = { + &dev_attr_fan1_input.attr, + &dev_attr_fan1_alarm.attr, + &dev_attr_fan1_fault.attr, + &dev_attr_fan1_target.attr, + &dev_attr_fan1_div.attr, + &dev_attr_fan1_pulses.attr, + &dev_attr_pwm1.attr, + &dev_attr_pwm1_mode.attr, + &dev_attr_pwm1_enable.attr, + NULL +}; + +static const struct attribute_group g762_group = { + .attrs = g762_attributes, +}; + +/* + * Enable both fan failure detection and fan out of control protection. The + * function does not protect change/access to data structure; it must thus + * only be called during initialization. + */ +static inline int g762_fan_init(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct g762_data *data = g762_update_client(dev); + + if (IS_ERR(data)) + return PTR_ERR(data); + + data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL; + data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC; + data->valid = false; + + return i2c_smbus_write_byte_data(client, G762_REG_FAN_CMD1, + data->fan_cmd1); +} + +static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct g762_data *data; + int ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + data = devm_kzalloc(&client->dev, sizeof(struct g762_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + i2c_set_clientdata(client, data); + data->client = client; + mutex_init(&data->update_lock); + + /* Enable fan failure detection and fan out of control protection */ + ret = g762_fan_init(&client->dev); + if (ret) + return ret; + + /* Get configuration via DT ... */ + ret = g762_of_clock_enable(client); + if (ret) + return ret; + ret = g762_of_prop_import(client); + if (ret) + goto clock_dis; + /* ... or platform_data */ + ret = g762_pdata_prop_import(client); + if (ret) + goto clock_dis; + + /* Register sysfs hooks */ + ret = sysfs_create_group(&client->dev.kobj, &g762_group); + if (ret) + goto clock_dis; + + data->hwmon_dev = hwmon_device_register(&client->dev); + if (IS_ERR(data->hwmon_dev)) { + ret = PTR_ERR(data->hwmon_dev); + goto sysfs_rem; + } + + return 0; + + sysfs_rem: + sysfs_remove_group(&client->dev.kobj, &g762_group); + + clock_dis: + g762_of_clock_disable(client); + + return ret; +} + +static int g762_remove(struct i2c_client *client) +{ + struct g762_data *data = i2c_get_clientdata(client); + + hwmon_device_unregister(data->hwmon_dev); + sysfs_remove_group(&client->dev.kobj, &g762_group); + g762_of_clock_disable(client); + + return 0; +} + +static struct i2c_driver g762_driver = { + .driver = { + .name = DRVNAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(g762_dt_match), + }, + .probe = g762_probe, + .remove = g762_remove, + .id_table = g762_id, +}; + +module_i2c_driver(g762_driver); + +MODULE_AUTHOR("Arnaud EBALARD <arno@natisbad.org>"); +MODULE_DESCRIPTION("GMT G762/G763 driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/platform_data/g762.h b/include/linux/platform_data/g762.h new file mode 100644 index 000000000000..d3c51283764d --- /dev/null +++ b/include/linux/platform_data/g762.h @@ -0,0 +1,37 @@ +/* + * Platform data structure for g762 fan controller driver + * + * Copyright (C) 2013, Arnaud EBALARD <arno@natisbad.org> + * + * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#ifndef __LINUX_PLATFORM_DATA_G762_H__ +#define __LINUX_PLATFORM_DATA_G762_H__ + +/* + * Following structure can be used to set g762 driver platform specific data + * during board init. Note that passing a sparse structure is possible but + * will result in non-specified attributes to be set to default value, hence + * overloading those installed during boot (e.g. by u-boot). + */ + +struct g762_platform_data { + u32 fan_startv; + u32 fan_gear_mode; + u32 pwm_polarity; + u32 clk_freq; +}; + +#endif /* __LINUX_PLATFORM_DATA_G762_H__ */ |
