ACPI: add support for Smart Battery

Most batteries today are ACPI "Control Method" batteries,
but some models ship with the older "Smart Battery"
that requires this code.

Rich Townsend and Bruno Ducrot were the original authors.
Vladimir Lebedev updated to run on latest kernel.

http://bugzilla.kernel.org/show_bug.cgi?id=3734

Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 420 insertions, 0 deletions

diff --git a/drivers/acpi/i2c_ec.c b/drivers/acpi/i2c_ec.c
new file mode 100644
index 000000000000..72478a665c8c
--- /dev/null
+++ b/drivers/acpi/i2c_ec.c
@@ -0,0 +1,420 @@
+/*
+ * SMBus driver for ACPI Embedded Controller ($Revision: 1.3 $)
+ *
+ * Copyright (c) 2002, 2005 Ducrot Bruno
+ * Copyright (c) 2005 Rich Townsend (tiny hacks & tweaks)
+ *
+ * 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 version 2.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+
+#include "i2c_ec.h"
+
+#define xudelay(t)      udelay(t)
+#define xmsleep(t)      msleep(t)
+
+#define ACPI_EC_HC_COMPONENT    0x00080000
+#define ACPI_EC_HC_CLASS        "ec_hc_smbus"
+#define ACPI_EC_HC_HID          "ACPI0001"
+#define ACPI_EC_HC_DRIVER_NAME  "ACPI EC HC smbus driver"
+#define ACPI_EC_HC_DEVICE_NAME  "EC HC smbus"
+
+#define _COMPONENT              ACPI_EC_HC_COMPONENT
+
+ACPI_MODULE_NAME("acpi_smbus")
+
+static int acpi_ec_hc_add(struct acpi_device *device);
+static int acpi_ec_hc_remove(struct acpi_device *device, int type);
+
+static struct acpi_driver acpi_ec_hc_driver = {
+        .name = ACPI_EC_HC_DRIVER_NAME,
+        .class = ACPI_EC_HC_CLASS,
+        .ids = ACPI_EC_HC_HID,
+        .ops = {
+                .add = acpi_ec_hc_add,
+                .remove = acpi_ec_hc_remove,
+                },
+};
+
+/* Various bit mask for EC_SC (R) */
+#define OBF             0x01
+#define IBF             0x02
+#define CMD             0x08
+#define BURST           0x10
+#define SCI_EVT         0x20
+#define SMI_EVT         0x40
+
+/* Commands for EC_SC (W) */
+#define RD_EC           0x80
+#define WR_EC           0x81
+#define BE_EC           0x82
+#define BD_EC           0x83
+#define QR_EC           0x84
+
+/*
+ * ACPI 2.0 chapter 13 SMBus 2.0 EC register model
+ */
+
+#define ACPI_EC_SMB_PRTCL       0x00    /* protocol, PEC */
+#define ACPI_EC_SMB_STS         0x01    /* status */
+#define ACPI_EC_SMB_ADDR        0x02    /* address */
+#define ACPI_EC_SMB_CMD         0x03    /* command */
+#define ACPI_EC_SMB_DATA        0x04    /* 32 data registers */
+#define ACPI_EC_SMB_BCNT        0x24    /* number of data bytes */
+#define ACPI_EC_SMB_ALRM_A      0x25    /* alarm address */
+#define ACPI_EC_SMB_ALRM_D      0x26    /* 2 bytes alarm data */
+
+#define ACPI_EC_SMB_STS_DONE    0x80
+#define ACPI_EC_SMB_STS_ALRM    0x40
+#define ACPI_EC_SMB_STS_RES     0x20
+#define ACPI_EC_SMB_STS_STATUS  0x1f
+
+#define ACPI_EC_SMB_STATUS_OK           0x00
+#define ACPI_EC_SMB_STATUS_FAIL         0x07
+#define ACPI_EC_SMB_STATUS_DNAK         0x10
+#define ACPI_EC_SMB_STATUS_DERR         0x11
+#define ACPI_EC_SMB_STATUS_CMD_DENY     0x12
+#define ACPI_EC_SMB_STATUS_UNKNOWN      0x13
+#define ACPI_EC_SMB_STATUS_ACC_DENY     0x17
+#define ACPI_EC_SMB_STATUS_TIMEOUT      0x18
+#define ACPI_EC_SMB_STATUS_NOTSUP       0x19
+#define ACPI_EC_SMB_STATUS_BUSY         0x1A
+#define ACPI_EC_SMB_STATUS_PEC          0x1F
+
+#define ACPI_EC_SMB_PRTCL_WRITE                 0x00
+#define ACPI_EC_SMB_PRTCL_READ                  0x01
+#define ACPI_EC_SMB_PRTCL_QUICK                 0x02
+#define ACPI_EC_SMB_PRTCL_BYTE                  0x04
+#define ACPI_EC_SMB_PRTCL_BYTE_DATA             0x06
+#define ACPI_EC_SMB_PRTCL_WORD_DATA             0x08
+#define ACPI_EC_SMB_PRTCL_BLOCK_DATA            0x0a
+#define ACPI_EC_SMB_PRTCL_PROC_CALL             0x0c
+#define ACPI_EC_SMB_PRTCL_BLOCK_PROC_CALL       0x0d
+#define ACPI_EC_SMB_PRTCL_I2C_BLOCK_DATA        0x4a
+#define ACPI_EC_SMB_PRTCL_PEC                   0x80
+
+/* Length of pre/post transaction sleep (msec) */
+#define ACPI_EC_SMB_TRANSACTION_SLEEP           1
+#define ACPI_EC_SMB_ACCESS_SLEEP1               1
+#define ACPI_EC_SMB_ACCESS_SLEEP2               10
+
+static int acpi_ec_smb_read(struct acpi_ec_smbus *smbus, u8 address, u8 * data)
+{
+        u8 val;
+        int err;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_smb_read");
+
+        err = ec_read(smbus->base + address, &val);
+        if (!err) {
+                *data = val;
+        }
+        xmsleep(ACPI_EC_SMB_TRANSACTION_SLEEP);
+        return (err);
+}
+
+static int acpi_ec_smb_write(struct acpi_ec_smbus *smbus, u8 address, u8 data)
+{
+        int err;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_smb_write");
+
+        err = ec_write(smbus->base + address, data);
+        return (err);
+}
+
+static int
+acpi_ec_smb_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
+                   char read_write, u8 command, int size,
+                   union i2c_smbus_data *data)
+{
+        struct acpi_ec_smbus *smbus = adap->algo_data;
+        unsigned char protocol, len = 0, pec, temp[2] = { 0, 0 };
+        int i;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_smb_access");
+
+        if (read_write == I2C_SMBUS_READ) {
+                protocol = ACPI_EC_SMB_PRTCL_READ;
+        } else {
+                protocol = ACPI_EC_SMB_PRTCL_WRITE;
+        }
+        pec = (flags & I2C_CLIENT_PEC) ? ACPI_EC_SMB_PRTCL_PEC : 0;
+
+        switch (size) {
+
+        case I2C_SMBUS_QUICK:
+                protocol |= ACPI_EC_SMB_PRTCL_QUICK;
+                read_write = I2C_SMBUS_WRITE;
+                break;
+
+        case I2C_SMBUS_BYTE:
+                if (read_write == I2C_SMBUS_WRITE) {
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->byte);
+                }
+                protocol |= ACPI_EC_SMB_PRTCL_BYTE;
+                break;
+
+        case I2C_SMBUS_BYTE_DATA:
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                if (read_write == I2C_SMBUS_WRITE) {
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->byte);
+                }
+                protocol |= ACPI_EC_SMB_PRTCL_BYTE_DATA;
+                break;
+
+        case I2C_SMBUS_WORD_DATA:
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                if (read_write == I2C_SMBUS_WRITE) {
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->word);
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + 1,
+                                          data->word >> 8);
+                }
+                protocol |= ACPI_EC_SMB_PRTCL_WORD_DATA | pec;
+                break;
+
+        case I2C_SMBUS_BLOCK_DATA:
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                if (read_write == I2C_SMBUS_WRITE) {
+                        len = min_t(u8, data->block[0], 32);
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
+                        for (i = 0; i < len; i++)
+                                acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
+                                                  data->block[i + 1]);
+                }
+                protocol |= ACPI_EC_SMB_PRTCL_BLOCK_DATA | pec;
+                break;
+
+        case I2C_SMBUS_I2C_BLOCK_DATA:
+                len = min_t(u8, data->block[0], 32);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
+                if (read_write == I2C_SMBUS_WRITE) {
+                        for (i = 0; i < len; i++) {
+                                acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
+                                                  data->block[i + 1]);
+                        }
+                }
+                protocol |= ACPI_EC_SMB_PRTCL_I2C_BLOCK_DATA;
+                break;
+
+        case I2C_SMBUS_PROC_CALL:
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA, data->word);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + 1, data->word >> 8);
+                protocol = ACPI_EC_SMB_PRTCL_PROC_CALL | pec;
+                read_write = I2C_SMBUS_READ;
+                break;
+
+        case I2C_SMBUS_BLOCK_PROC_CALL:
+                protocol |= pec;
+                len = min_t(u8, data->block[0], 31);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_CMD, command);
+                acpi_ec_smb_write(smbus, ACPI_EC_SMB_BCNT, len);
+                for (i = 0; i < len; i++)
+                        acpi_ec_smb_write(smbus, ACPI_EC_SMB_DATA + i,
+                                          data->block[i + 1]);
+                protocol = ACPI_EC_SMB_PRTCL_BLOCK_PROC_CALL | pec;
+                read_write = I2C_SMBUS_READ;
+                break;
+
+        default:
+                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "EC SMBus adapter: "
+                                  "Unsupported transaction %d\n", size));
+                return (-1);
+        }
+
+        acpi_ec_smb_write(smbus, ACPI_EC_SMB_ADDR, addr << 1);
+        acpi_ec_smb_write(smbus, ACPI_EC_SMB_PRTCL, protocol);
+
+        acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);
+
+        if (~temp[0] & ACPI_EC_SMB_STS_DONE) {
+                xudelay(500);
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);
+        }
+        if (~temp[0] & ACPI_EC_SMB_STS_DONE) {
+                xmsleep(ACPI_EC_SMB_ACCESS_SLEEP2);
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_STS, temp + 0);
+        }
+        if ((~temp[0] & ACPI_EC_SMB_STS_DONE)
+            || (temp[0] & ACPI_EC_SMB_STS_STATUS)) {
+                return (-1);
+        }
+
+        if (read_write == I2C_SMBUS_WRITE) {
+                return (0);
+        }
+
+        switch (size) {
+
+        case I2C_SMBUS_BYTE:
+        case I2C_SMBUS_BYTE_DATA:
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA, &data->byte);
+                break;
+
+        case I2C_SMBUS_WORD_DATA:
+        case I2C_SMBUS_PROC_CALL:
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA, temp + 0);
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA + 1, temp + 1);
+                data->word = (temp[1] << 8) | temp[0];
+                break;
+
+        case I2C_SMBUS_BLOCK_DATA:
+        case I2C_SMBUS_BLOCK_PROC_CALL:
+                len = 0;
+                acpi_ec_smb_read(smbus, ACPI_EC_SMB_BCNT, &len);
+                len = min_t(u8, len, 32);
+        case I2C_SMBUS_I2C_BLOCK_DATA:
+                for (i = 0; i < len; i++)
+                        acpi_ec_smb_read(smbus, ACPI_EC_SMB_DATA + i,
+                                         data->block + i + 1);
+                data->block[0] = len;
+                break;
+        }
+
+        return (0);
+}
+
+static u32 acpi_ec_smb_func(struct i2c_adapter *adapter)
+{
+        ACPI_FUNCTION_TRACE("acpi_ec_smb_func");
+
+        return (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+                I2C_FUNC_SMBUS_BLOCK_DATA |
+                I2C_FUNC_SMBUS_PROC_CALL |
+                I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
+                I2C_FUNC_SMBUS_I2C_BLOCK | I2C_FUNC_SMBUS_HWPEC_CALC);
+}
+
+static struct i2c_algorithm acpi_ec_smbus_algorithm = {
+        .smbus_xfer = acpi_ec_smb_access,
+        .functionality = acpi_ec_smb_func,
+};
+
+static int acpi_ec_hc_add(struct acpi_device *device)
+{
+        int status;
+        unsigned long val;
+        struct acpi_ec_hc *ec_hc;
+        struct acpi_ec_smbus *smbus;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_hc_add");
+
+        if (!device) {
+                return_VALUE(-EINVAL);
+        }
+
+        ec_hc = kmalloc(sizeof(struct acpi_ec_hc), GFP_KERNEL);
+        if (!ec_hc) {
+                return_VALUE(-ENOMEM);
+        }
+        memset(ec_hc, 0, sizeof(struct acpi_ec_hc));
+
+        smbus = kmalloc(sizeof(struct acpi_ec_smbus), GFP_KERNEL);
+        if (!smbus) {
+                kfree(ec_hc);
+                return_VALUE(-ENOMEM);
+        }
+        memset(smbus, 0, sizeof(struct acpi_ec_smbus));
+
+        ec_hc->handle = device->handle;
+        strcpy(acpi_device_name(device), ACPI_EC_HC_DEVICE_NAME);
+        strcpy(acpi_device_class(device), ACPI_EC_HC_CLASS);
+        acpi_driver_data(device) = ec_hc;
+
+        status = acpi_evaluate_integer(ec_hc->handle, "_EC", NULL, &val);
+        if (ACPI_FAILURE(status)) {
+                ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Error obtaining _EC\n"));
+                kfree(ec_hc->smbus);
+                kfree(smbus);
+                return_VALUE(-EIO);
+        }
+
+        smbus->ec = acpi_driver_data(device->parent);
+        smbus->base = (val & 0xff00ull) >> 8;
+        smbus->alert = val & 0xffull;
+
+        smbus->adapter.owner = THIS_MODULE;
+        smbus->adapter.algo = &acpi_ec_smbus_algorithm;
+        smbus->adapter.algo_data = smbus;
+
+        if (i2c_add_adapter(&smbus->adapter)) {
+                ACPI_DEBUG_PRINT((ACPI_DB_WARN,
+                                  "EC SMBus adapter: Failed to register adapter\n"));
+                kfree(smbus);
+                kfree(ec_hc);
+                return_VALUE(-EIO);
+        }
+
+        ec_hc->smbus = smbus;
+
+        printk(KERN_INFO PREFIX "%s [%s]\n",
+               acpi_device_name(device), acpi_device_bid(device));
+
+        return_VALUE(AE_OK);
+}
+
+static int acpi_ec_hc_remove(struct acpi_device *device, int type)
+{
+        struct acpi_ec_hc *ec_hc;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_hc_remove");
+
+        if (!device) {
+                return_VALUE(-EINVAL);
+        }
+        ec_hc = acpi_driver_data(device);
+
+        i2c_del_adapter(&ec_hc->smbus->adapter);
+        kfree(ec_hc->smbus);
+        kfree(ec_hc);
+
+        return_VALUE(AE_OK);
+}
+
+static int __init acpi_ec_hc_init(void)
+{
+        int result;
+
+        ACPI_FUNCTION_TRACE("acpi_ec_hc_init");
+        result = acpi_bus_register_driver(&acpi_ec_hc_driver);
+        if (result < 0) {
+                return_VALUE(-ENODEV);
+        }
+        return_VALUE(0);
+}
+
+static void __exit acpi_ec_hc_exit(void)
+{
+        ACPI_FUNCTION_TRACE("acpi_ec_hc_exit");
+        acpi_bus_unregister_driver(&acpi_ec_hc_driver);
+}
+
+struct acpi_ec_hc *acpi_get_ec_hc(struct acpi_device *device)
+{
+        ACPI_FUNCTION_TRACE("acpi_get_ec_hc");
+        return ((struct acpi_ec_hc *)acpi_driver_data(device->parent));
+}
+
+EXPORT_SYMBOL(acpi_get_ec_hc);
+
+module_init(acpi_ec_hc_init);
+module_exit(acpi_ec_hc_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ducrot Bruno");
+MODULE_DESCRIPTION("ACPI EC SMBus driver");