Initial import

1 files changed, 619 insertions, 0 deletions

diff --git a/drivers/hwmon/sch56xx-common.c b/drivers/hwmon/sch56xx-common.c
new file mode 100644
index 000000000..738681983
--- /dev/null
+++ b/drivers/hwmon/sch56xx-common.c
@@ -0,0 +1,619 @@
+/***************************************************************************
+ *   Copyright (C) 2010-2012 Hans de Goede <hdegoede@redhat.com>           *
+ *                                                                         *
+ *   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.             *
+ ***************************************************************************/
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/watchdog.h>
+#include <linux/miscdevice.h>
+#include <linux/uaccess.h>
+#include <linux/kref.h>
+#include <linux/slab.h>
+#include "sch56xx-common.h"
+
+/* Insmod parameters */
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+#define SIO_SCH56XX_LD_EM	0x0C	/* Embedded uController Logical Dev */
+#define SIO_UNLOCK_KEY		0x55	/* Key to enable Super-I/O */
+#define SIO_LOCK_KEY		0xAA	/* Key to disable Super-I/O */
+
+#define SIO_REG_LDSEL		0x07	/* Logical device select */
+#define SIO_REG_DEVID		0x20	/* Device ID */
+#define SIO_REG_ENABLE		0x30	/* Logical device enable */
+#define SIO_REG_ADDR		0x66	/* Logical device address (2 bytes) */
+
+#define SIO_SCH5627_ID		0xC6	/* Chipset ID */
+#define SIO_SCH5636_ID		0xC7	/* Chipset ID */
+
+#define REGION_LENGTH		10
+
+#define SCH56XX_CMD_READ	0x02
+#define SCH56XX_CMD_WRITE	0x03
+
+/* Watchdog registers */
+#define SCH56XX_REG_WDOG_PRESET		0x58B
+#define SCH56XX_REG_WDOG_CONTROL	0x58C
+#define SCH56XX_WDOG_TIME_BASE_SEC	0x01
+#define SCH56XX_REG_WDOG_OUTPUT_ENABLE	0x58E
+#define SCH56XX_WDOG_OUTPUT_ENABLE	0x02
+
+struct sch56xx_watchdog_data {
+	u16 addr;
+	struct mutex *io_lock;
+	struct kref kref;
+	struct watchdog_info wdinfo;
+	struct watchdog_device wddev;
+	u8 watchdog_preset;
+	u8 watchdog_control;
+	u8 watchdog_output_enable;
+};
+
+static struct platform_device *sch56xx_pdev;
+
+/* Super I/O functions */
+static inline int superio_inb(int base, int reg)
+{
+	outb(reg, base);
+	return inb(base + 1);
+}
+
+static inline int superio_enter(int base)
+{
+	/* Don't step on other drivers' I/O space by accident */
+	if (!request_muxed_region(base, 2, "sch56xx")) {
+		pr_err("I/O address 0x%04x already in use\n", base);
+		return -EBUSY;
+	}
+
+	outb(SIO_UNLOCK_KEY, base);
+
+	return 0;
+}
+
+static inline void superio_select(int base, int ld)
+{
+	outb(SIO_REG_LDSEL, base);
+	outb(ld, base + 1);
+}
+
+static inline void superio_exit(int base)
+{
+	outb(SIO_LOCK_KEY, base);
+	release_region(base, 2);
+}
+
+static int sch56xx_send_cmd(u16 addr, u8 cmd, u16 reg, u8 v)
+{
+	u8 val;
+	int i;
+	/*
+	 * According to SMSC for the commands we use the maximum time for
+	 * the EM to respond is 15 ms, but testing shows in practice it
+	 * responds within 15-32 reads, so we first busy poll, and if
+	 * that fails sleep a bit and try again until we are way past
+	 * the 15 ms maximum response time.
+	 */
+	const int max_busy_polls = 64;
+	const int max_lazy_polls = 32;
+
+	/* (Optional) Write-Clear the EC to Host Mailbox Register */
+	val = inb(addr + 1);
+	outb(val, addr + 1);
+
+	/* Set Mailbox Address Pointer to first location in Region 1 */
+	outb(0x00, addr + 2);
+	outb(0x80, addr + 3);
+
+	/* Write Request Packet Header */
+	outb(cmd, addr + 4); /* VREG Access Type read:0x02 write:0x03 */
+	outb(0x01, addr + 5); /* # of Entries: 1 Byte (8-bit) */
+	outb(0x04, addr + 2); /* Mailbox AP to first data entry loc. */
+
+	/* Write Value field */
+	if (cmd == SCH56XX_CMD_WRITE)
+		outb(v, addr + 4);
+
+	/* Write Address field */
+	outb(reg & 0xff, addr + 6);
+	outb(reg >> 8, addr + 7);
+
+	/* Execute the Random Access Command */
+	outb(0x01, addr); /* Write 01h to the Host-to-EC register */
+
+	/* EM Interface Polling "Algorithm" */
+	for (i = 0; i < max_busy_polls + max_lazy_polls; i++) {
+		if (i >= max_busy_polls)
+			msleep(1);
+		/* Read Interrupt source Register */
+		val = inb(addr + 8);
+		/* Write Clear the interrupt source bits */
+		if (val)
+			outb(val, addr + 8);
+		/* Command Completed ? */
+		if (val & 0x01)
+			break;
+	}
+	if (i == max_busy_polls + max_lazy_polls) {
+		pr_err("Max retries exceeded reading virtual register 0x%04hx (%d)\n",
+		       reg, 1);
+		return -EIO;
+	}
+
+	/*
+	 * According to SMSC we may need to retry this, but sofar I've always
+	 * seen this succeed in 1 try.
+	 */
+	for (i = 0; i < max_busy_polls; i++) {
+		/* Read EC-to-Host Register */
+		val = inb(addr + 1);
+		/* Command Completed ? */
+		if (val == 0x01)
+			break;
+
+		if (i == 0)
+			pr_warn("EC reports: 0x%02x reading virtual register 0x%04hx\n",
+				(unsigned int)val, reg);
+	}
+	if (i == max_busy_polls) {
+		pr_err("Max retries exceeded reading virtual register 0x%04hx (%d)\n",
+		       reg, 2);
+		return -EIO;
+	}
+
+	/*
+	 * According to the SMSC app note we should now do:
+	 *
+	 * Set Mailbox Address Pointer to first location in Region 1 *
+	 * outb(0x00, addr + 2);
+	 * outb(0x80, addr + 3);
+	 *
+	 * But if we do that things don't work, so let's not.
+	 */
+
+	/* Read Value field */
+	if (cmd == SCH56XX_CMD_READ)
+		return inb(addr + 4);
+
+	return 0;
+}
+
+int sch56xx_read_virtual_reg(u16 addr, u16 reg)
+{
+	return sch56xx_send_cmd(addr, SCH56XX_CMD_READ, reg, 0);
+}
+EXPORT_SYMBOL(sch56xx_read_virtual_reg);
+
+int sch56xx_write_virtual_reg(u16 addr, u16 reg, u8 val)
+{
+	return sch56xx_send_cmd(addr, SCH56XX_CMD_WRITE, reg, val);
+}
+EXPORT_SYMBOL(sch56xx_write_virtual_reg);
+
+int sch56xx_read_virtual_reg16(u16 addr, u16 reg)
+{
+	int lsb, msb;
+
+	/* Read LSB first, this will cause the matching MSB to be latched */
+	lsb = sch56xx_read_virtual_reg(addr, reg);
+	if (lsb < 0)
+		return lsb;
+
+	msb = sch56xx_read_virtual_reg(addr, reg + 1);
+	if (msb < 0)
+		return msb;
+
+	return lsb | (msb << 8);
+}
+EXPORT_SYMBOL(sch56xx_read_virtual_reg16);
+
+int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
+			       int high_nibble)
+{
+	int msb, lsn;
+
+	/* Read MSB first, this will cause the matching LSN to be latched */
+	msb = sch56xx_read_virtual_reg(addr, msb_reg);
+	if (msb < 0)
+		return msb;
+
+	lsn = sch56xx_read_virtual_reg(addr, lsn_reg);
+	if (lsn < 0)
+		return lsn;
+
+	if (high_nibble)
+		return (msb << 4) | (lsn >> 4);
+	else
+		return (msb << 4) | (lsn & 0x0f);
+}
+EXPORT_SYMBOL(sch56xx_read_virtual_reg12);
+
+/*
+ * Watchdog routines
+ */
+
+/* Release our data struct when we're unregistered *and*
+   all references to our watchdog device are released */
+static void watchdog_release_resources(struct kref *r)
+{
+	struct sch56xx_watchdog_data *data =
+		container_of(r, struct sch56xx_watchdog_data, kref);
+	kfree(data);
+}
+
+static int watchdog_set_timeout(struct watchdog_device *wddev,
+				unsigned int timeout)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+	unsigned int resolution;
+	u8 control;
+	int ret;
+
+	/* 1 second or 60 second resolution? */
+	if (timeout <= 255)
+		resolution = 1;
+	else
+		resolution = 60;
+
+	if (timeout < resolution || timeout > (resolution * 255))
+		return -EINVAL;
+
+	if (resolution == 1)
+		control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC;
+	else
+		control = data->watchdog_control & ~SCH56XX_WDOG_TIME_BASE_SEC;
+
+	if (data->watchdog_control != control) {
+		mutex_lock(data->io_lock);
+		ret = sch56xx_write_virtual_reg(data->addr,
+						SCH56XX_REG_WDOG_CONTROL,
+						control);
+		mutex_unlock(data->io_lock);
+		if (ret)
+			return ret;
+
+		data->watchdog_control = control;
+	}
+
+	/*
+	 * Remember new timeout value, but do not write as that (re)starts
+	 * the watchdog countdown.
+	 */
+	data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
+	wddev->timeout = data->watchdog_preset * resolution;
+
+	return 0;
+}
+
+static int watchdog_start(struct watchdog_device *wddev)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+	int ret;
+	u8 val;
+
+	/*
+	 * The sch56xx's watchdog cannot really be started / stopped
+	 * it is always running, but we can avoid the timer expiring
+	 * from causing a system reset by clearing the output enable bit.
+	 *
+	 * The sch56xx's watchdog will set the watchdog event bit, bit 0
+	 * of the second interrupt source register (at base-address + 9),
+	 * when the timer expires.
+	 *
+	 * This will only cause a system reset if the 0-1 flank happens when
+	 * output enable is true. Setting output enable after the flank will
+	 * not cause a reset, nor will the timer expiring a second time.
+	 * This means we must clear the watchdog event bit in case it is set.
+	 *
+	 * The timer may still be running (after a recent watchdog_stop) and
+	 * mere milliseconds away from expiring, so the timer must be reset
+	 * first!
+	 */
+
+	mutex_lock(data->io_lock);
+
+	/* 1. Reset the watchdog countdown counter */
+	ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
+					data->watchdog_preset);
+	if (ret)
+		goto leave;
+
+	/* 2. Enable output */
+	val = data->watchdog_output_enable | SCH56XX_WDOG_OUTPUT_ENABLE;
+	ret = sch56xx_write_virtual_reg(data->addr,
+					SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
+	if (ret)
+		goto leave;
+
+	data->watchdog_output_enable = val;
+
+	/* 3. Clear the watchdog event bit if set */
+	val = inb(data->addr + 9);
+	if (val & 0x01)
+		outb(0x01, data->addr + 9);
+
+leave:
+	mutex_unlock(data->io_lock);
+	return ret;
+}
+
+static int watchdog_trigger(struct watchdog_device *wddev)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+	int ret;
+
+	/* Reset the watchdog countdown counter */
+	mutex_lock(data->io_lock);
+	ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
+					data->watchdog_preset);
+	mutex_unlock(data->io_lock);
+
+	return ret;
+}
+
+static int watchdog_stop(struct watchdog_device *wddev)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+	int ret = 0;
+	u8 val;
+
+	val = data->watchdog_output_enable & ~SCH56XX_WDOG_OUTPUT_ENABLE;
+	mutex_lock(data->io_lock);
+	ret = sch56xx_write_virtual_reg(data->addr,
+					SCH56XX_REG_WDOG_OUTPUT_ENABLE, val);
+	mutex_unlock(data->io_lock);
+	if (ret)
+		return ret;
+
+	data->watchdog_output_enable = val;
+	return 0;
+}
+
+static void watchdog_ref(struct watchdog_device *wddev)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+
+	kref_get(&data->kref);
+}
+
+static void watchdog_unref(struct watchdog_device *wddev)
+{
+	struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+
+	kref_put(&data->kref, watchdog_release_resources);
+}
+
+static const struct watchdog_ops watchdog_ops = {
+	.owner		= THIS_MODULE,
+	.start		= watchdog_start,
+	.stop		= watchdog_stop,
+	.ping		= watchdog_trigger,
+	.set_timeout	= watchdog_set_timeout,
+	.ref		= watchdog_ref,
+	.unref		= watchdog_unref,
+};
+
+struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
+	u16 addr, u32 revision, struct mutex *io_lock, int check_enabled)
+{
+	struct sch56xx_watchdog_data *data;
+	int err, control, output_enable;
+
+	/* Cache the watchdog registers */
+	mutex_lock(io_lock);
+	control =
+		sch56xx_read_virtual_reg(addr, SCH56XX_REG_WDOG_CONTROL);
+	output_enable =
+		sch56xx_read_virtual_reg(addr, SCH56XX_REG_WDOG_OUTPUT_ENABLE);
+	mutex_unlock(io_lock);
+
+	if (control < 0)
+		return NULL;
+	if (output_enable < 0)
+		return NULL;
+	if (check_enabled && !(output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)) {
+		pr_warn("Watchdog not enabled by BIOS, not registering\n");
+		return NULL;
+	}
+
+	data = kzalloc(sizeof(struct sch56xx_watchdog_data), GFP_KERNEL);
+	if (!data)
+		return NULL;
+
+	data->addr = addr;
+	data->io_lock = io_lock;
+	kref_init(&data->kref);
+
+	strlcpy(data->wdinfo.identity, "sch56xx watchdog",
+		sizeof(data->wdinfo.identity));
+	data->wdinfo.firmware_version = revision;
+	data->wdinfo.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT;
+	if (!nowayout)
+		data->wdinfo.options |= WDIOF_MAGICCLOSE;
+
+	data->wddev.info = &data->wdinfo;
+	data->wddev.ops = &watchdog_ops;
+	data->wddev.parent = parent;
+	data->wddev.timeout = 60;
+	data->wddev.min_timeout = 1;
+	data->wddev.max_timeout = 255 * 60;
+	if (nowayout)
+		set_bit(WDOG_NO_WAY_OUT, &data->wddev.status);
+	if (output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)
+		set_bit(WDOG_ACTIVE, &data->wddev.status);
+
+	/* Since the watchdog uses a downcounter there is no register to read
+	   the BIOS set timeout from (if any was set at all) ->
+	   Choose a preset which will give us a 1 minute timeout */
+	if (control & SCH56XX_WDOG_TIME_BASE_SEC)
+		data->watchdog_preset = 60; /* seconds */
+	else
+		data->watchdog_preset = 1; /* minute */
+
+	data->watchdog_control = control;
+	data->watchdog_output_enable = output_enable;
+
+	watchdog_set_drvdata(&data->wddev, data);
+	err = watchdog_register_device(&data->wddev);
+	if (err) {
+		pr_err("Registering watchdog chardev: %d\n", err);
+		kfree(data);
+		return NULL;
+	}
+
+	return data;
+}
+EXPORT_SYMBOL(sch56xx_watchdog_register);
+
+void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data)
+{
+	watchdog_unregister_device(&data->wddev);
+	kref_put(&data->kref, watchdog_release_resources);
+	/* Don't touch data after this it may have been free-ed! */
+}
+EXPORT_SYMBOL(sch56xx_watchdog_unregister);
+
+/*
+ * platform dev find, add and remove functions
+ */
+
+static int __init sch56xx_find(int sioaddr, const char **name)
+{
+	u8 devid;
+	unsigned short address;
+	int err;
+
+	err = superio_enter(sioaddr);
+	if (err)
+		return err;
+
+	devid = superio_inb(sioaddr, SIO_REG_DEVID);
+	switch (devid) {
+	case SIO_SCH5627_ID:
+		*name = "sch5627";
+		break;
+	case SIO_SCH5636_ID:
+		*name = "sch5636";
+		break;
+	default:
+		pr_debug("Unsupported device id: 0x%02x\n",
+			 (unsigned int)devid);
+		err = -ENODEV;
+		goto exit;
+	}
+
+	superio_select(sioaddr, SIO_SCH56XX_LD_EM);
+
+	if (!(superio_inb(sioaddr, SIO_REG_ENABLE) & 0x01)) {
+		pr_warn("Device not activated\n");
+		err = -ENODEV;
+		goto exit;
+	}
+
+	/*
+	 * Warning the order of the low / high byte is the other way around
+	 * as on most other superio devices!!
+	 */
+	address = superio_inb(sioaddr, SIO_REG_ADDR) |
+		   superio_inb(sioaddr, SIO_REG_ADDR + 1) << 8;
+	if (address == 0) {
+		pr_warn("Base address not set\n");
+		err = -ENODEV;
+		goto exit;
+	}
+	err = address;
+
+exit:
+	superio_exit(sioaddr);
+	return err;
+}
+
+static int __init sch56xx_device_add(int address, const char *name)
+{
+	struct resource res = {
+		.start	= address,
+		.end	= address + REGION_LENGTH - 1,
+		.flags	= IORESOURCE_IO,
+	};
+	int err;
+
+	sch56xx_pdev = platform_device_alloc(name, address);
+	if (!sch56xx_pdev)
+		return -ENOMEM;
+
+	res.name = sch56xx_pdev->name;
+	err = acpi_check_resource_conflict(&res);
+	if (err)
+		goto exit_device_put;
+
+	err = platform_device_add_resources(sch56xx_pdev, &res, 1);
+	if (err) {
+		pr_err("Device resource addition failed\n");
+		goto exit_device_put;
+	}
+
+	err = platform_device_add(sch56xx_pdev);
+	if (err) {
+		pr_err("Device addition failed\n");
+		goto exit_device_put;
+	}
+
+	return 0;
+
+exit_device_put:
+	platform_device_put(sch56xx_pdev);
+
+	return err;
+}
+
+static int __init sch56xx_init(void)
+{
+	int address;
+	const char *name = NULL;
+
+	address = sch56xx_find(0x4e, &name);
+	if (address < 0)
+		address = sch56xx_find(0x2e, &name);
+	if (address < 0)
+		return address;
+
+	return sch56xx_device_add(address, name);
+}
+
+static void __exit sch56xx_exit(void)
+{
+	platform_device_unregister(sch56xx_pdev);
+}
+
+MODULE_DESCRIPTION("SMSC SCH56xx Hardware Monitoring Common Code");
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_LICENSE("GPL");
+
+module_init(sch56xx_init);
+module_exit(sch56xx_exit);