feat(reimaden): add platform support kernel module

spec/reimaden/ac71/fan.c

@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "pr.h"
+
+#include <linux/version.h>
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(5, 12, 0)
+static inline int fixp_linear_interpolate(int x0, int y0, int x1, int y1, int x)
+{
+	if (y0 == y1 || x == x0)
+		return y0;
+	if (x1 == x0 || x == x1)
+		return y1;
+
+	return y0 + ((y1 - y0) * (x - x0) / (x1 - x0));
+}
+#else
+#include <linux/bug.h> /* fixp-arith.h needs it, but doesn't include it */
+#include <linux/fixp-arith.h>
+#endif
+
+#include <linux/lockdep.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+#include "ec.h"
+#include "fan.h"
+#include "util.h"
+
+/* ========================================================================== */
+
+static const uint16_t ac71_fan_rpm_addrs[] = {
+	FAN_RPM_1_ADDR,
+	FAN_RPM_2_ADDR,
+};
+
+static const uint16_t ac71_fan_pwm_addrs[] = {
+	FAN_PWM_1_ADDR,
+	FAN_PWM_2_ADDR,
+};
+
+static const uint16_t ac71_fan_temp_addrs[] = {
+	FAN_TEMP_1_ADDR,
+	FAN_TEMP_2_ADDR,
+};
+
+/* ========================================================================== */
+
+static DEFINE_MUTEX(fan_lock);
+
+/* ========================================================================== */
+
+static int ac71_fan_get_status(void)
+{
+	return ec_read_byte(FAN_CTRL_ADDR);
+}
+
+/* 'fan_lock' must be held */
+static int ac71_fan_get_mode_unlocked(void)
+{
+	int err;
+
+	lockdep_assert_held(&fan_lock);
+
+	err = ec_read_byte(CTRL_1_ADDR);
+	if (err < 0)
+		return err;
+
+	if (err & CTRL_1_MANUAL_MODE) {
+		err = ac71_fan_get_status();
+		if (err < 0)
+			return err;
+
+		if (err & FAN_CTRL_FAN_BOOST) {
+			err = ac71_fan_get_pwm(0);
+
+			if (err < 0)
+				return err;
+
+			if (err == FAN_MAX_PWM)
+				err = 0; /* disengaged */
+			else
+				err = 1; /* manual */
+
+		} else if (err & FAN_CTRL_AUTO) {
+			err = 2; /* automatic fan control */
+		} else {
+			err = 1; /* manual */
+		}
+	} else {
+		err = 2; /* automatic fan control */
+	}
+
+	return err;
+}
+
+/* ========================================================================== */
+
+int ac71_fan_get_rpm(uint8_t fan_index)
+{
+	union ac71_ec_result res;
+	int err;
+
+	if (fan_index >= ARRAY_SIZE(ac71_fan_rpm_addrs))
+		return -EINVAL;
+
+	err = ac71_ec_read(ac71_fan_rpm_addrs[fan_index], &res);
+
+	if (err)
+		return err;
+
+	return res.bytes.b1 << 8 | res.bytes.b2;
+}
+
+int ac71_fan_query_abnorm(void)
+{
+	int res = ec_read_byte(CTRL_1_ADDR);
+
+	if (res < 0)
+		return res;
+
+	return !!(res & CTRL_1_FAN_ABNORMAL);
+}
+
+int ac71_fan_get_pwm(uint8_t fan_index)
+{
+	int err;
+
+	if (fan_index >= ARRAY_SIZE(ac71_fan_pwm_addrs))
+		return -EINVAL;
+
+	err = ec_read_byte(ac71_fan_pwm_addrs[fan_index]);
+	if (err < 0)
+		return err;
+
+	return fixp_linear_interpolate(0, 0, FAN_MAX_PWM, U8_MAX, err);
+}
+
+int ac71_fan_set_pwm(uint8_t fan_index, uint8_t pwm)
+{
+	if (fan_index >= ARRAY_SIZE(ac71_fan_pwm_addrs))
+		return -EINVAL;
+
+	return ec_write_byte(ac71_fan_pwm_addrs[fan_index],
+			     fixp_linear_interpolate(0, 0,
+						     U8_MAX, FAN_MAX_PWM,
+						     pwm));
+}
+
+int ac71_fan_get_temp(uint8_t fan_index)
+{
+	if (fan_index >= ARRAY_SIZE(ac71_fan_temp_addrs))
+		return -EINVAL;
+
+	return ec_read_byte(ac71_fan_temp_addrs[fan_index]);
+}
+
+int ac71_fan_get_mode(void)
+{
+	int err = mutex_lock_interruptible(&fan_lock);
+
+	if (err)
+		return err;
+
+	err = ac71_fan_get_mode_unlocked();
+
+	mutex_unlock(&fan_lock);
+	return err;
+}
+
+int ac71_fan_set_mode(uint8_t mode)
+{
+	int err, oldpwm;
+
+	err = mutex_lock_interruptible(&fan_lock);
+	if (err)
+		return err;
+
+	switch (mode) {
+	case 0:
+		err = ec_write_byte(FAN_CTRL_ADDR, FAN_CTRL_FAN_BOOST);
+		if (err)
+			goto out;
+
+		err = ac71_fan_set_pwm(0, FAN_MAX_PWM);
+		break;
+	case 1:
+		oldpwm = err = ac71_fan_get_pwm(0);
+		if (err < 0)
+			goto out;
+
+		err = ec_write_byte(FAN_CTRL_ADDR, FAN_CTRL_FAN_BOOST);
+		if (err < 0)
+			goto out;
+
+		err = ac71_fan_set_pwm(0, oldpwm);
+		if (err < 0)
+			(void) ec_write_byte(FAN_CTRL_ADDR, 0x80 | FAN_CTRL_AUTO);
+			/* try to restore automatic fan control */
+
+		break;
+	case 2:
+		err = ec_write_byte(FAN_CTRL_ADDR, 0x80 | FAN_CTRL_AUTO);
+		break;
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+out:
+	mutex_unlock(&fan_lock);
+	return err;
+}