[PATCHv3 1/3] Add support for GMT G762/G763 PWM fan controller
Arnaud Ebalard
arno at natisbad.org
Sun Jun 2 16:14:19 EDT 2013
Signed-off-by: Arnaud Ebalard <arno at natisbad.org>
---
drivers/hwmon/Kconfig | 10 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/g762.c | 1179 ++++++++++++++++++++++++++++++++++++
include/linux/platform_data/g762.h | 51 ++
4 files changed, 1241 insertions(+)
create mode 100644 drivers/hwmon/g762.c
create mode 100644 include/linux/platform_data/g762.h
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 0428e8a..142bdf8 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -456,6 +456,16 @@ 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 d17d3e6..4f0fb52 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 0000000..6678a60
--- /dev/null
+++ b/drivers/hwmon/g762.c
@@ -0,0 +1,1179 @@
+/*
+ * 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 at 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, 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 at gmail.com>
+ *
+ * based on g760a code written by Herbert Valerio Riedel <hvr at gnu.org>
+ * Copyright (C) 2007 Herbert Valerio Riedel <hvr at 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/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 OUT_MODE_PWM 1
+#define OUT_MODE_DC 0
+
+#define FAN_MODE_CLOSED_LOOP 2
+#define FAN_MODE_OPEN_LOOP 1
+
+/* 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 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 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 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;
+
+ /* update mutex */
+ struct mutex update_lock;
+
+ /* board specific parameters. */
+ u32 clk;
+
+ /* 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)
+ */
+};
+
+/*
+ * sysfs PWM interface uses value from 0 to 255 when g762 FAN_SET_CNT register
+ * uses values from 255 (off) to 0 (full speed). Note that FAN_SET_OUT register
+ * uses values from 0 (off) to 255 (full speed), i.e. does not need translation.
+ */
+#define PWM_FROM_CNT(cnt) (0xff - (cnt))
+#define PWM_TO_CNT(pwm) (0xff - (pwm))
+
+/*
+ * Convert count value from fan controller registers (FAN_SET_CNT/FAN_ACT_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, u16 p,
+ u8 clk_div, u8 gear_mult)
+{
+ if (cnt == 0xff) /* cnt to 255 stops the fan */
+ return 0;
+
+ return (clk * 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, u16 p,
+ u8 clk_div, u8 gear_mult)
+{
+ if (!rpm) /* to stop the fan, set cnt to 255 */
+ return 0xff;
+
+ return clamp_val(((clk * 30 * gear_mult)/(rpm * p * clk_div)), 0, 255);
+}
+
+/*
+ * simple wrappers for i2c_smbus_{read,write}_byte_data() providing
+ * additional info on error
+ */
+static inline int g762_read_byte(const struct i2c_client *client, u8 reg,
+ u8 *dest)
+{
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(client, reg);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to read reg %x02x, err %d\n",
+ (int)reg, ret);
+ return ret;
+ }
+ *dest = ret;
+
+ return 0;
+}
+
+static inline int g762_write_byte(const struct i2c_client *client, u8 reg,
+ u8 val)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(client, reg, val);
+ if (ret < 0)
+ dev_err(&client->dev, "failed to write reg %x02x, err %d\n",
+ (int)reg, ret);
+
+ return ret;
+}
+
+/* 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 = g762_read_byte(client, G762_REG_SET_CNT, &data->set_cnt);
+ if (ret)
+ goto out;
+
+ ret = g762_read_byte(client, G762_REG_ACT_CNT, &data->act_cnt);
+ if (ret < 0)
+ goto out;
+
+ ret = g762_read_byte(client, G762_REG_FAN_STA, &data->fan_sta);
+ if (ret < 0)
+ goto out;
+
+ ret = g762_read_byte(client, G762_REG_SET_OUT, &data->set_out);
+ if (ret < 0)
+ goto out;
+
+ ret = g762_read_byte(client, G762_REG_FAN_CMD1, &data->fan_cmd1);
+ if (ret < 0)
+ goto out;
+
+ ret = g762_read_byte(client, G762_REG_FAN_CMD2, &data->fan_cmd2);
+ if (ret < 0)
+ goto out;
+
+ 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 passing hardware characteristics via DT. Some of those
+ * are also used by sysfs handlers (write functions) later in the file.
+ */
+
+/* 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 = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ switch (val) {
+ case OUT_MODE_PWM:
+ data->fan_cmd1 |= G762_REG_FAN_CMD1_OUT_MODE;
+ break;
+ case OUT_MODE_DC:
+ data->fan_cmd1 &= ~G762_REG_FAN_CMD1_OUT_MODE;
+ break;
+ default:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/*
+ * Set reference clock. Accepted values are between 0 and 0xffffff.
+ * Note that this is a characteristics of the system but an internal
+ * parameter, i.e. value is not passed to the device.
+ */
+static int do_set_pwm_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;
+
+ data->clk = val;
+
+ return 0;
+}
+
+/* Set fan clock divisor. Accepted values are 1, 2, 4 and 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 = -EINVAL;
+
+ 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:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Set fan gear mode. Accepted values are 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 = -EINVAL;
+
+ 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:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD2, data->fan_cmd2);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Set pulse per revolution value. 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 = -EINVAL;
+
+ 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:
+ goto out;
+ }
+ ret = g762_write_byte(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 = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ switch (val) {
+ case FAN_MODE_OPEN_LOOP:
+ data->fan_cmd1 &= ~G762_REG_FAN_CMD1_FAN_MODE;
+ break;
+ case FAN_MODE_CLOSED_LOOP:
+ data->fan_cmd1 |= G762_REG_FAN_CMD1_FAN_MODE;
+ break;
+ default:
+ goto out;
+ }
+
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Set PWM polarity (0 for negative duty, 1 for positive 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 = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ switch (val) {
+ case 0: /* i.e. negative duty */
+ data->fan_cmd1 &= ~G762_REG_FAN_CMD1_PWM_POLARITY;
+ break;
+ case 1: /* i.e. positive duty */
+ data->fan_cmd1 |= G762_REG_FAN_CMD1_PWM_POLARITY;
+ break;
+ default:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/*
+ * Set pwm value. Accepted values are between 0 (stops the fan) and 255 (full
+ * speed). Note that the chip register used for setting the value depends on
+ * current fan mode of the device (closed or open-loop).
+ */
+static int do_set_pwm(struct device *dev, unsigned long val)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct g762_data *data = g762_update_client(dev);
+ int ret;
+ u8 reg;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ if (val > 255)
+ return -EINVAL;
+
+ mutex_lock(&data->update_lock);
+ if (data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE) { /* closed-loop */
+ val = PWM_TO_CNT(val);
+ data->set_cnt = val;
+ reg = G762_REG_SET_CNT;
+ } else { /* open-loop */
+ data->set_out = val;
+ reg = G762_REG_SET_OUT;
+ }
+ ret = g762_write_byte(client, reg, (u8)val);
+ data->valid = false;
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Set fan RPM value. This only makes sense in closed-loop mode. */
+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 = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ if (data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE) { /* closed-loop */
+ data->set_cnt = cnt_from_rpm(val, data->clk,
+ PULSE_FROM_REG(data->fan_cmd1),
+ CLKDIV_FROM_REG(data->fan_cmd1),
+ GEARMULT_FROM_REG(data->fan_cmd2));
+ ret = g762_write_byte(client, G762_REG_SET_CNT, data->set_cnt);
+ data->valid = false;
+ }
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Enable/disable fan failure detection. Accepted values are 1 and 0. */
+static int do_fan_failure_detection_toggle(struct device *dev,
+ unsigned long enable)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct g762_data *data = g762_update_client(dev);
+ int ret = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ switch (enable) {
+ case 0:
+ data->fan_cmd1 &= ~G762_REG_FAN_CMD1_DET_FAN_FAIL;
+ break;
+ case 1:
+ data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_FAIL;
+ break;
+ default:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/* Enable/disable fan out of control detection. Accepted values are 1 and 0 */
+static int do_fan_ooc_detection_toggle(struct device *dev, unsigned int enable)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct g762_data *data = g762_update_client(dev);
+ int ret = -EINVAL;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ switch (enable) {
+ case 0:
+ data->fan_cmd1 &= ~G762_REG_FAN_CMD1_DET_FAN_OOC;
+ break;
+ case 1:
+ data->fan_cmd1 |= G762_REG_FAN_CMD1_DET_FAN_OOC;
+ break;
+ default:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD1, data->fan_cmd1);
+ out:
+ 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 = -EINVAL;
+
+ 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;
+ data->valid = false;
+ break;
+ case 1:
+ data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
+ data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_1;
+ data->valid = false;
+ break;
+ case 2:
+ data->fan_cmd2 &= ~G762_REG_FAN_CMD2_FAN_STARTV_0;
+ data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
+ data->valid = false;
+ break;
+ case 3:
+ data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_0;
+ data->fan_cmd2 |= G762_REG_FAN_CMD2_FAN_STARTV_1;
+ data->valid = false;
+ break;
+ default:
+ goto out;
+ }
+ ret = g762_write_byte(client, G762_REG_FAN_CMD2, data->fan_cmd2);
+ data->valid = false;
+ out:
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+/*
+ * Configuration-related definitions
+ */
+
+static inline int g762_one_prop_commit(struct i2c_client *client,
+ u32 pval, const char *pname,
+ int (*psetter)(struct device *dev,
+ unsigned long val))
+{
+ int ret = 0;
+
+ if (pval & G762_VAL_TEST_BIT) {
+ pval &= G762_VAL_TEST_MASK; /* recover val (clear test bit) */
+ if ((*psetter)(&client->dev, pval)) {
+ dev_err(&client->dev, "unable to set %s (%d)\n",
+ pname, pval);
+ ret = -EINVAL;
+ }
+ }
+
+ return ret;
+}
+
+static int g762_platform_data_commit(struct i2c_client *client,
+ struct g762_platform_data *pdata)
+{
+ int ret;
+
+ ret = g762_one_prop_commit(client, pdata->fan_startv,
+ "fan_startv", do_set_fan_startv);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->fan_div,
+ "fan_div", do_set_fan_div);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->fan_pulses,
+ "fan_pulses", do_set_fan_pulses);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->pwm_freq,
+ "pwm_freq", do_set_pwm_freq);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->fan_gear_mode,
+ "fan_gear_mode", do_set_fan_gear_mode);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->pwm_polarity,
+ "pwm_polarity", do_set_pwm_polarity);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->pwm_mode,
+ "pwm_mode", do_set_pwm_mode);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->pwm_enable,
+ "pwm_enable", do_set_pwm_enable);
+ if (ret < 0)
+ return ret;
+
+ ret = g762_one_prop_commit(client, pdata->fan_target,
+ "fan_target", do_set_fan_target);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+/*
+ * Helpers to import hardware characteristics from .dts file and overload
+ * default platform data values.
+ */
+
+#ifdef CONFIG_OF
+static struct of_device_id g762_dt_match[] = {
+ { .compatible = "gmt,g762" },
+ { .compatible = "gmt,g763" },
+ { },
+};
+
+static inline void g762_of_import_one_prop(struct i2c_client *client,
+ u32 *dest, const char *pname)
+{
+ const __be32 *prop;
+ int len;
+
+ prop = of_get_property(client->dev.of_node, pname, &len);
+ if (prop && len == sizeof(u32)) {
+ *dest = G762_ATTR_VAL(be32_to_cpu(prop[0]));
+ dev_dbg(&client->dev, "found %s (%d)\n", pname, *dest);
+ }
+}
+
+static void g762_platform_data_of_overload(struct i2c_client *client,
+ struct g762_platform_data *pdata)
+{
+ if (!client->dev.of_node)
+ return;
+
+ g762_of_import_one_prop(client, &pdata->fan_startv, "fan_startv");
+ g762_of_import_one_prop(client, &pdata->fan_gear_mode, "fan_gear_mode");
+ g762_of_import_one_prop(client, &pdata->fan_div, "fan_div");
+ g762_of_import_one_prop(client, &pdata->fan_pulses, "fan_pulses");
+ g762_of_import_one_prop(client, &pdata->fan_target, "fan_target");
+ g762_of_import_one_prop(client, &pdata->pwm_polarity, "pwm_polarity");
+ g762_of_import_one_prop(client, &pdata->pwm_enable, "pwm_enable");
+ g762_of_import_one_prop(client, &pdata->pwm_freq, "pwm_freq");
+ g762_of_import_one_prop(client, &pdata->pwm_mode, "pwm_mode");
+}
+#else
+static void g762_platform_data_of_overload(struct i2c_client *client,
+ struct g762_platform_data *pdata) { }
+#endif
+
+/*
+ * helper to overload driver parameters from board init file for those
+ * not already converted to device tree
+ */
+static void g762_platform_data_overload(struct i2c_client *client,
+ struct g762_platform_data *pdata)
+{
+ struct g762_platform_data *opdata = client->dev.platform_data;
+
+ if (!opdata)
+ return;
+
+ if (opdata->fan_startv & G762_VAL_TEST_BIT)
+ pdata->fan_startv = opdata->fan_startv;
+ if (opdata->fan_gear_mode & G762_VAL_TEST_BIT)
+ pdata->fan_gear_mode = opdata->fan_gear_mode;
+ if (opdata->fan_div & G762_VAL_TEST_BIT)
+ pdata->fan_div = opdata->fan_div;
+ if (opdata->fan_pulses & G762_VAL_TEST_BIT)
+ pdata->fan_pulses = opdata->fan_pulses;
+ if (opdata->fan_target & G762_VAL_TEST_BIT)
+ pdata->fan_target = opdata->fan_target;
+ if (opdata->pwm_polarity & G762_VAL_TEST_BIT)
+ pdata->pwm_polarity = opdata->pwm_polarity;
+ if (opdata->pwm_enable & G762_VAL_TEST_BIT)
+ pdata->pwm_enable = opdata->pwm_enable;
+ if (opdata->pwm_freq & G762_VAL_TEST_BIT)
+ pdata->pwm_freq = opdata->pwm_freq;
+ if (opdata->pwm_mode & G762_VAL_TEST_BIT)
+ pdata->pwm_mode = opdata->pwm_mode;
+}
+
+/*
+ * sysfs attributes
+ */
+
+/*
+ * Read function for fan1_input sysfs file. Return current fan RPM value, or
+ * 0 if fan is out of control. The function is available in both closed and
+ * open-loop mode.
+ */
+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,
+ PULSE_FROM_REG(data->fan_cmd1),
+ CLKDIV_FROM_REG(data->fan_cmd1),
+ 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", 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 pwm1_enable. Get and set the 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 "no-control" mode is not supported by g762,
+ * -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 the fan speed
+ * in both open and closed-loop mode. Speed is given as a relative value
+ * between 0 and 255, where 255 is maximum speed. 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_pwm(struct device *dev, struct device_attribute *da,
+ char *buf)
+{
+ struct g762_data *data = g762_update_client(dev);
+ int val;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ if (data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE) /* closed-loop */
+ val = PWM_FROM_CNT(data->set_cnt);
+ else /* open-loop */
+ val = data->set_out;
+ mutex_unlock(&data->update_lock);
+
+ return sprintf(buf, "%d\n", val);
+}
+
+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. The functions both return
+ * -EINVAL when called in open-loop mode.
+ *
+ * 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);
+ ssize_t ret = -EINVAL;
+ unsigned int rpm;
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ mutex_lock(&data->update_lock);
+ if (data->fan_cmd1 & G762_REG_FAN_CMD1_FAN_MODE) { /* closed-loop */
+ rpm = rpm_from_cnt(data->set_cnt, data->clk,
+ PULSE_FROM_REG(data->fan_cmd1),
+ CLKDIV_FROM_REG(data->fan_cmd1),
+ GEARMULT_FROM_REG(data->fan_cmd2));
+ ret = sprintf(buf, "%u\n", rpm);
+ }
+ mutex_unlock(&data->update_lock);
+
+ return ret;
+}
+
+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);
+
+/* 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_pwm1.attr,
+ &dev_attr_pwm1_mode.attr,
+ &dev_attr_pwm1_enable.attr,
+ NULL
+};
+
+static const struct attribute_group g762_group = {
+ .attrs = g762_attributes,
+};
+
+static int g762_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+ struct g762_platform_data pdata = { .pwm_freq = G762_ATTR_VAL(32768) };
+ struct g762_data *data;
+ int err;
+
+ 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 protection and fan fail detection by default */
+ do_fan_ooc_detection_toggle(&client->dev, 1);
+ do_fan_failure_detection_toggle(&client->dev, 1);
+
+ /*
+ * Set default configuration values before passing the structure
+ * first to overload routine used by boards non converted to DT and
+ * then to OF helper (to overload them using those provided by .dts
+ * file, if any). Final result is then commited.
+ */
+ g762_platform_data_overload(client, &pdata);
+ g762_platform_data_of_overload(client, &pdata);
+ err = g762_platform_data_commit(client, &pdata);
+ if (err)
+ return err;
+
+ /* Register sysfs hooks */
+ err = sysfs_create_group(&client->dev.kobj, &g762_group);
+ if (err)
+ return err;
+
+ data->hwmon_dev = (struct device *)hwmon_device_register(&client->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ err = PTR_ERR(data->hwmon_dev);
+ goto err_out;
+ }
+
+ return 0;
+
+ err_out:
+ sysfs_remove_group(&client->dev.kobj, &g762_group);
+ return err;
+}
+
+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);
+
+ 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 at 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 0000000..a1f9e05
--- /dev/null
+++ b/include/linux/platform_data/g762.h
@@ -0,0 +1,51 @@
+/*
+ * Platform data structure for g762 fan controller driver
+ *
+ * Copyright (C) 2013, Arnaud EBALARD <arno at 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. Attributes must *always* be set using G762_ATTR_VAL()
+ * macro defined below, i.e. it is not possible to pass a value directly.
+ * Defining a sparse structure is possible. For instance, if one only needs
+ * to set pwm_freq to 8192 and fan_pulses to 2, the following can be done:
+ *
+ * static struct g762_platform_data pdata = { .pwm_freq = G762_ATTR_VAL(8192),
+ * .fan_pulses = G762_ATTR_VAL(2), };
+ *
+ */
+
+#define G762_VAL_TEST_BIT (1 << 31)
+#define G762_VAL_TEST_MASK (~G762_VAL_TEST_BIT)
+#define G762_ATTR_VAL(val) ((val) | G762_VAL_TEST_BIT)
+
+struct g762_platform_data {
+ u32 fan_startv;
+ u32 fan_gear_mode;
+ u32 fan_div;
+ u32 fan_pulses;
+ u32 fan_target;
+ u32 pwm_polarity;
+ u32 pwm_enable;
+ u32 pwm_freq;
+ u32 pwm_mode;
+};
+
+#endif /* __LINUX_PLATFORM_DATA_G762_H__ */
--
1.7.10.4
More information about the linux-arm-kernel
mailing list