diff options
Diffstat (limited to 'drivers/hwmon/g762.c')
| -rw-r--r-- | drivers/hwmon/g762.c | 1149 | 
1 files changed, 1149 insertions, 0 deletions
diff --git a/drivers/hwmon/g762.c b/drivers/hwmon/g762.c new file mode 100644 index 00000000000..98a8618d8fb --- /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 const 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 = dev_get_platdata(&client->dev); +	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");  | 
