Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/hwmon/axi-fan-control.c b/drivers/hwmon/axi-fan-control.c
new file mode 100644
index 0000000..e3f6b03
--- /dev/null
+++ b/drivers/hwmon/axi-fan-control.c
@@ -0,0 +1,465 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Fan Control HDL CORE driver
+ *
+ * Copyright 2019 Analog Devices Inc.
+ */
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/fpga/adi-axi-common.h>
+#include <linux/hwmon.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+/* register map */
+#define ADI_REG_RSTN		0x0080
+#define ADI_REG_PWM_WIDTH	0x0084
+#define ADI_REG_TACH_PERIOD	0x0088
+#define ADI_REG_TACH_TOLERANCE	0x008c
+#define ADI_REG_PWM_PERIOD	0x00c0
+#define ADI_REG_TACH_MEASUR	0x00c4
+#define ADI_REG_TEMPERATURE	0x00c8
+
+#define ADI_REG_IRQ_MASK	0x0040
+#define ADI_REG_IRQ_PENDING	0x0044
+#define ADI_REG_IRQ_SRC		0x0048
+
+/* IRQ sources */
+#define ADI_IRQ_SRC_PWM_CHANGED		BIT(0)
+#define ADI_IRQ_SRC_TACH_ERR		BIT(1)
+#define ADI_IRQ_SRC_TEMP_INCREASE	BIT(2)
+#define ADI_IRQ_SRC_NEW_MEASUR		BIT(3)
+#define ADI_IRQ_SRC_MASK		GENMASK(3, 0)
+#define ADI_IRQ_MASK_OUT_ALL		0xFFFFFFFFU
+
+#define SYSFS_PWM_MAX			255
+
+struct axi_fan_control_data {
+	void __iomem *base;
+	struct device *hdev;
+	unsigned long clk_rate;
+	int irq;
+	/* pulses per revolution */
+	u32 ppr;
+	bool hw_pwm_req;
+	bool update_tacho_params;
+	u8 fan_fault;
+};
+
+static inline void axi_iowrite(const u32 val, const u32 reg,
+			       const struct axi_fan_control_data *ctl)
+{
+	iowrite32(val, ctl->base + reg);
+}
+
+static inline u32 axi_ioread(const u32 reg,
+			     const struct axi_fan_control_data *ctl)
+{
+	return ioread32(ctl->base + reg);
+}
+
+static long axi_fan_control_get_pwm_duty(const struct axi_fan_control_data *ctl)
+{
+	u32 pwm_width = axi_ioread(ADI_REG_PWM_WIDTH, ctl);
+	u32 pwm_period = axi_ioread(ADI_REG_PWM_PERIOD, ctl);
+	/*
+	 * PWM_PERIOD is a RO register set by the core. It should never be 0.
+	 * For now we are trusting the HW...
+	 */
+	return DIV_ROUND_CLOSEST(pwm_width * SYSFS_PWM_MAX, pwm_period);
+}
+
+static int axi_fan_control_set_pwm_duty(const long val,
+					struct axi_fan_control_data *ctl)
+{
+	u32 pwm_period = axi_ioread(ADI_REG_PWM_PERIOD, ctl);
+	u32 new_width;
+	long __val = clamp_val(val, 0, SYSFS_PWM_MAX);
+
+	new_width = DIV_ROUND_CLOSEST(__val * pwm_period, SYSFS_PWM_MAX);
+
+	axi_iowrite(new_width, ADI_REG_PWM_WIDTH, ctl);
+
+	return 0;
+}
+
+static long axi_fan_control_get_fan_rpm(const struct axi_fan_control_data *ctl)
+{
+	const u32 tach = axi_ioread(ADI_REG_TACH_MEASUR, ctl);
+
+	if (tach == 0)
+		/* should we return error, EAGAIN maybe? */
+		return 0;
+	/*
+	 * The tacho period should be:
+	 *      TACH = 60/(ppr * rpm), where rpm is revolutions per second
+	 *      and ppr is pulses per revolution.
+	 * Given the tacho period, we can multiply it by the input clock
+	 * so that we know how many clocks we need to have this period.
+	 * From this, we can derive the RPM value.
+	 */
+	return DIV_ROUND_CLOSEST(60 * ctl->clk_rate, ctl->ppr * tach);
+}
+
+static int axi_fan_control_read_temp(struct device *dev, u32 attr, long *val)
+{
+	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);
+	long raw_temp;
+
+	switch (attr) {
+	case hwmon_temp_input:
+		raw_temp = axi_ioread(ADI_REG_TEMPERATURE, ctl);
+		/*
+		 * The formula for the temperature is:
+		 *      T = (ADC * 501.3743 / 2^bits) - 273.6777
+		 * It's multiplied by 1000 to have millidegrees as
+		 * specified by the hwmon sysfs interface.
+		 */
+		*val = ((raw_temp * 501374) >> 16) - 273677;
+		return 0;
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_read_fan(struct device *dev, u32 attr, long *val)
+{
+	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);
+
+	switch (attr) {
+	case hwmon_fan_fault:
+		*val = ctl->fan_fault;
+		/* clear it now */
+		ctl->fan_fault = 0;
+		return 0;
+	case hwmon_fan_input:
+		*val = axi_fan_control_get_fan_rpm(ctl);
+		return 0;
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_read_pwm(struct device *dev, u32 attr, long *val)
+{
+	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		*val = axi_fan_control_get_pwm_duty(ctl);
+		return 0;
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_write_pwm(struct device *dev, u32 attr, long val)
+{
+	struct axi_fan_control_data *ctl = dev_get_drvdata(dev);
+
+	switch (attr) {
+	case hwmon_pwm_input:
+		return axi_fan_control_set_pwm_duty(val, ctl);
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_read_labels(struct device *dev,
+				       enum hwmon_sensor_types type,
+				       u32 attr, int channel, const char **str)
+{
+	switch (type) {
+	case hwmon_fan:
+		*str = "FAN";
+		return 0;
+	case hwmon_temp:
+		*str = "SYSMON4";
+		return 0;
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_read(struct device *dev,
+				enum hwmon_sensor_types type,
+				u32 attr, int channel, long *val)
+{
+	switch (type) {
+	case hwmon_fan:
+		return axi_fan_control_read_fan(dev, attr, val);
+	case hwmon_pwm:
+		return axi_fan_control_read_pwm(dev, attr, val);
+	case hwmon_temp:
+		return axi_fan_control_read_temp(dev, attr, val);
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static int axi_fan_control_write(struct device *dev,
+				 enum hwmon_sensor_types type,
+				 u32 attr, int channel, long val)
+{
+	switch (type) {
+	case hwmon_pwm:
+		return axi_fan_control_write_pwm(dev, attr, val);
+	default:
+		return -ENOTSUPP;
+	}
+}
+
+static umode_t axi_fan_control_fan_is_visible(const u32 attr)
+{
+	switch (attr) {
+	case hwmon_fan_input:
+	case hwmon_fan_fault:
+	case hwmon_fan_label:
+		return 0444;
+	default:
+		return 0;
+	}
+}
+
+static umode_t axi_fan_control_pwm_is_visible(const u32 attr)
+{
+	switch (attr) {
+	case hwmon_pwm_input:
+		return 0644;
+	default:
+		return 0;
+	}
+}
+
+static umode_t axi_fan_control_temp_is_visible(const u32 attr)
+{
+	switch (attr) {
+	case hwmon_temp_input:
+	case hwmon_temp_label:
+		return 0444;
+	default:
+		return 0;
+	}
+}
+
+static umode_t axi_fan_control_is_visible(const void *data,
+					  enum hwmon_sensor_types type,
+					  u32 attr, int channel)
+{
+	switch (type) {
+	case hwmon_fan:
+		return axi_fan_control_fan_is_visible(attr);
+	case hwmon_pwm:
+		return axi_fan_control_pwm_is_visible(attr);
+	case hwmon_temp:
+		return axi_fan_control_temp_is_visible(attr);
+	default:
+		return 0;
+	}
+}
+
+/*
+ * This core has two main ways of changing the PWM duty cycle. It is done,
+ * either by a request from userspace (writing on pwm1_input) or by the
+ * core itself. When the change is done by the core, it will use predefined
+ * parameters to evaluate the tach signal and, on that case we cannot set them.
+ * On the other hand, when the request is done by the user, with some arbitrary
+ * value that the core does not now about, we have to provide the tach
+ * parameters so that, the core can evaluate the signal. On the IRQ handler we
+ * distinguish this by using the ADI_IRQ_SRC_TEMP_INCREASE interrupt. This tell
+ * us that the CORE requested a new duty cycle. After this, there is 5s delay
+ * on which the core waits for the fan rotation speed to stabilize. After this
+ * we get ADI_IRQ_SRC_PWM_CHANGED irq where we will decide if we need to set
+ * the tach parameters or not on the next tach measurement cycle (corresponding
+ * already to the ney duty cycle) based on the %ctl->hw_pwm_req flag.
+ */
+static irqreturn_t axi_fan_control_irq_handler(int irq, void *data)
+{
+	struct axi_fan_control_data *ctl = (struct axi_fan_control_data *)data;
+	u32 irq_pending = axi_ioread(ADI_REG_IRQ_PENDING, ctl);
+	u32 clear_mask;
+
+	if (irq_pending & ADI_IRQ_SRC_NEW_MEASUR) {
+		if (ctl->update_tacho_params) {
+			u32 new_tach = axi_ioread(ADI_REG_TACH_MEASUR, ctl);
+
+			/* get 25% tolerance */
+			u32 tach_tol = DIV_ROUND_CLOSEST(new_tach * 25, 100);
+			/* set new tacho parameters */
+			axi_iowrite(new_tach, ADI_REG_TACH_PERIOD, ctl);
+			axi_iowrite(tach_tol, ADI_REG_TACH_TOLERANCE, ctl);
+			ctl->update_tacho_params = false;
+		}
+	}
+
+	if (irq_pending & ADI_IRQ_SRC_PWM_CHANGED) {
+		/*
+		 * if the pwm changes on behalf of software,
+		 * we need to provide new tacho parameters to the core.
+		 * Wait for the next measurement for that...
+		 */
+		if (!ctl->hw_pwm_req) {
+			ctl->update_tacho_params = true;
+		} else {
+			ctl->hw_pwm_req = false;
+			sysfs_notify(&ctl->hdev->kobj, NULL, "pwm1");
+		}
+	}
+
+	if (irq_pending & ADI_IRQ_SRC_TEMP_INCREASE)
+		/* hardware requested a new pwm */
+		ctl->hw_pwm_req = true;
+
+	if (irq_pending & ADI_IRQ_SRC_TACH_ERR)
+		ctl->fan_fault = 1;
+
+	/* clear all interrupts */
+	clear_mask = irq_pending & ADI_IRQ_SRC_MASK;
+	axi_iowrite(clear_mask, ADI_REG_IRQ_PENDING, ctl);
+
+	return IRQ_HANDLED;
+}
+
+static int axi_fan_control_init(struct axi_fan_control_data *ctl,
+				const struct device_node *np)
+{
+	int ret;
+
+	/* get fan pulses per revolution */
+	ret = of_property_read_u32(np, "pulses-per-revolution", &ctl->ppr);
+	if (ret)
+		return ret;
+
+	/* 1, 2 and 4 are the typical and accepted values */
+	if (ctl->ppr != 1 && ctl->ppr != 2 && ctl->ppr != 4)
+		return -EINVAL;
+	/*
+	 * Enable all IRQs
+	 */
+	axi_iowrite(ADI_IRQ_MASK_OUT_ALL &
+		    ~(ADI_IRQ_SRC_NEW_MEASUR | ADI_IRQ_SRC_TACH_ERR |
+		      ADI_IRQ_SRC_PWM_CHANGED | ADI_IRQ_SRC_TEMP_INCREASE),
+		    ADI_REG_IRQ_MASK, ctl);
+
+	/* bring the device out of reset */
+	axi_iowrite(0x01, ADI_REG_RSTN, ctl);
+
+	return ret;
+}
+
+static const struct hwmon_channel_info *axi_fan_control_info[] = {
+	HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT),
+	HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT | HWMON_F_FAULT | HWMON_F_LABEL),
+	HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT | HWMON_T_LABEL),
+	NULL
+};
+
+static const struct hwmon_ops axi_fan_control_hwmon_ops = {
+	.is_visible = axi_fan_control_is_visible,
+	.read = axi_fan_control_read,
+	.write = axi_fan_control_write,
+	.read_string = axi_fan_control_read_labels,
+};
+
+static const struct hwmon_chip_info axi_chip_info = {
+	.ops = &axi_fan_control_hwmon_ops,
+	.info = axi_fan_control_info,
+};
+
+static const u32 version_1_0_0 = ADI_AXI_PCORE_VER(1, 0, 'a');
+
+static const struct of_device_id axi_fan_control_of_match[] = {
+	{ .compatible = "adi,axi-fan-control-1.00.a",
+		.data = (void *)&version_1_0_0},
+	{},
+};
+MODULE_DEVICE_TABLE(of, axi_fan_control_of_match);
+
+static int axi_fan_control_probe(struct platform_device *pdev)
+{
+	struct axi_fan_control_data *ctl;
+	struct clk *clk;
+	const struct of_device_id *id;
+	const char *name = "axi_fan_control";
+	u32 version;
+	int ret;
+
+	id = of_match_node(axi_fan_control_of_match, pdev->dev.of_node);
+	if (!id)
+		return -EINVAL;
+
+	ctl = devm_kzalloc(&pdev->dev, sizeof(*ctl), GFP_KERNEL);
+	if (!ctl)
+		return -ENOMEM;
+
+	ctl->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ctl->base))
+		return PTR_ERR(ctl->base);
+
+	clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "clk_get failed with %ld\n", PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	ctl->clk_rate = clk_get_rate(clk);
+	if (!ctl->clk_rate)
+		return -EINVAL;
+
+	version = axi_ioread(ADI_AXI_REG_VERSION, ctl);
+	if (ADI_AXI_PCORE_VER_MAJOR(version) !=
+	    ADI_AXI_PCORE_VER_MAJOR((*(u32 *)id->data))) {
+		dev_err(&pdev->dev, "Major version mismatch. Expected %d.%.2d.%c, Reported %d.%.2d.%c\n",
+			ADI_AXI_PCORE_VER_MAJOR((*(u32 *)id->data)),
+			ADI_AXI_PCORE_VER_MINOR((*(u32 *)id->data)),
+			ADI_AXI_PCORE_VER_PATCH((*(u32 *)id->data)),
+			ADI_AXI_PCORE_VER_MAJOR(version),
+			ADI_AXI_PCORE_VER_MINOR(version),
+			ADI_AXI_PCORE_VER_PATCH(version));
+		return -ENODEV;
+	}
+
+	ctl->irq = platform_get_irq(pdev, 0);
+	if (ctl->irq < 0)
+		return ctl->irq;
+
+	ret = devm_request_threaded_irq(&pdev->dev, ctl->irq, NULL,
+					axi_fan_control_irq_handler,
+					IRQF_ONESHOT | IRQF_TRIGGER_HIGH,
+					pdev->driver_override, ctl);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request an irq, %d", ret);
+		return ret;
+	}
+
+	ret = axi_fan_control_init(ctl, pdev->dev.of_node);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to initialize device\n");
+		return ret;
+	}
+
+	ctl->hdev = devm_hwmon_device_register_with_info(&pdev->dev,
+							 name,
+							 ctl,
+							 &axi_chip_info,
+							 NULL);
+
+	return PTR_ERR_OR_ZERO(ctl->hdev);
+}
+
+static struct platform_driver axi_fan_control_driver = {
+	.driver = {
+		.name = "axi_fan_control_driver",
+		.of_match_table = axi_fan_control_of_match,
+	},
+	.probe = axi_fan_control_probe,
+};
+module_platform_driver(axi_fan_control_driver);
+
+MODULE_AUTHOR("Nuno Sa <nuno.sa@analog.com>");
+MODULE_DESCRIPTION("Analog Devices Fan Control HDL CORE driver");
+MODULE_LICENSE("GPL");