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Diffstat (limited to 'drivers/i2c/busses/i2c-viapro.c')
-rw-r--r--drivers/i2c/busses/i2c-viapro.c499
1 files changed, 499 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-viapro.c b/drivers/i2c/busses/i2c-viapro.c
new file mode 100644
index 000000000..970ccdcbb
--- /dev/null
+++ b/drivers/i2c/busses/i2c-viapro.c
@@ -0,0 +1,499 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl>,
+ Philip Edelbrock <phil@netroedge.com>, Kyösti Mälkki <kmalkki@cc.hut.fi>,
+ Mark D. Studebaker <mdsxyz123@yahoo.com>
+ Copyright (C) 2005 - 2008 Jean Delvare <jdelvare@suse.de>
+
+*/
+
+/*
+ Supports the following VIA south bridges:
+
+ Chip name PCI ID REV I2C block
+ VT82C596A 0x3050 no
+ VT82C596B 0x3051 no
+ VT82C686A 0x3057 0x30 no
+ VT82C686B 0x3057 0x40 yes
+ VT8231 0x8235 no?
+ VT8233 0x3074 yes
+ VT8233A 0x3147 yes?
+ VT8235 0x3177 yes
+ VT8237R 0x3227 yes
+ VT8237A 0x3337 yes
+ VT8237S 0x3372 yes
+ VT8251 0x3287 yes
+ CX700 0x8324 yes
+ VX800/VX820 0x8353 yes
+ VX855/VX875 0x8409 yes
+
+ Note: we assume there can only be one device, with one SMBus interface.
+*/
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/ioport.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/io.h>
+
+static struct pci_dev *vt596_pdev;
+
+#define SMBBA1 0x90
+#define SMBBA2 0x80
+#define SMBBA3 0xD0
+
+/* SMBus address offsets */
+static unsigned short vt596_smba;
+#define SMBHSTSTS (vt596_smba + 0)
+#define SMBHSTCNT (vt596_smba + 2)
+#define SMBHSTCMD (vt596_smba + 3)
+#define SMBHSTADD (vt596_smba + 4)
+#define SMBHSTDAT0 (vt596_smba + 5)
+#define SMBHSTDAT1 (vt596_smba + 6)
+#define SMBBLKDAT (vt596_smba + 7)
+
+/* PCI Address Constants */
+
+/* SMBus data in configuration space can be found in two places,
+ We try to select the better one */
+
+static unsigned short SMBHSTCFG = 0xD2;
+
+/* Other settings */
+#define MAX_TIMEOUT 500
+
+/* VT82C596 constants */
+#define VT596_QUICK 0x00
+#define VT596_BYTE 0x04
+#define VT596_BYTE_DATA 0x08
+#define VT596_WORD_DATA 0x0C
+#define VT596_PROC_CALL 0x10
+#define VT596_BLOCK_DATA 0x14
+#define VT596_I2C_BLOCK_DATA 0x34
+
+
+/* If force is set to anything different from 0, we forcibly enable the
+ VT596. DANGEROUS! */
+static bool force;
+module_param(force, bool, 0);
+MODULE_PARM_DESC(force, "Forcibly enable the SMBus. DANGEROUS!");
+
+/* If force_addr is set to anything different from 0, we forcibly enable
+ the VT596 at the given address. VERY DANGEROUS! */
+static u16 force_addr;
+module_param_hw(force_addr, ushort, ioport, 0);
+MODULE_PARM_DESC(force_addr,
+ "Forcibly enable the SMBus at the given address. "
+ "EXTREMELY DANGEROUS!");
+
+
+static struct pci_driver vt596_driver;
+static struct i2c_adapter vt596_adapter;
+
+#define FEATURE_I2CBLOCK (1<<0)
+static unsigned int vt596_features;
+
+#ifdef DEBUG
+static void vt596_dump_regs(const char *msg, u8 size)
+{
+ dev_dbg(&vt596_adapter.dev, "%s: STS=%02x CNT=%02x CMD=%02x ADD=%02x "
+ "DAT=%02x,%02x\n", msg, inb_p(SMBHSTSTS), inb_p(SMBHSTCNT),
+ inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
+ inb_p(SMBHSTDAT1));
+
+ if (size == VT596_BLOCK_DATA
+ || size == VT596_I2C_BLOCK_DATA) {
+ int i;
+
+ dev_dbg(&vt596_adapter.dev, "BLK=");
+ for (i = 0; i < I2C_SMBUS_BLOCK_MAX / 2; i++)
+ printk("%02x,", inb_p(SMBBLKDAT));
+ printk("\n");
+ dev_dbg(&vt596_adapter.dev, " ");
+ for (; i < I2C_SMBUS_BLOCK_MAX - 1; i++)
+ printk("%02x,", inb_p(SMBBLKDAT));
+ printk("%02x\n", inb_p(SMBBLKDAT));
+ }
+}
+#else
+static inline void vt596_dump_regs(const char *msg, u8 size) { }
+#endif
+
+/* Return -1 on error, 0 on success */
+static int vt596_transaction(u8 size)
+{
+ int temp;
+ int result = 0;
+ int timeout = 0;
+
+ vt596_dump_regs("Transaction (pre)", size);
+
+ /* Make sure the SMBus host is ready to start transmitting */
+ if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
+ dev_dbg(&vt596_adapter.dev, "SMBus busy (0x%02x). "
+ "Resetting...\n", temp);
+
+ outb_p(temp, SMBHSTSTS);
+ if ((temp = inb_p(SMBHSTSTS)) & 0x1F) {
+ dev_err(&vt596_adapter.dev, "SMBus reset failed! "
+ "(0x%02x)\n", temp);
+ return -EBUSY;
+ }
+ }
+
+ /* Start the transaction by setting bit 6 */
+ outb_p(0x40 | size, SMBHSTCNT);
+
+ /* We will always wait for a fraction of a second */
+ do {
+ msleep(1);
+ temp = inb_p(SMBHSTSTS);
+ } while ((temp & 0x01) && (++timeout < MAX_TIMEOUT));
+
+ /* If the SMBus is still busy, we give up */
+ if (timeout == MAX_TIMEOUT) {
+ result = -ETIMEDOUT;
+ dev_err(&vt596_adapter.dev, "SMBus timeout!\n");
+ }
+
+ if (temp & 0x10) {
+ result = -EIO;
+ dev_err(&vt596_adapter.dev, "Transaction failed (0x%02x)\n",
+ size);
+ }
+
+ if (temp & 0x08) {
+ result = -EIO;
+ dev_err(&vt596_adapter.dev, "SMBus collision!\n");
+ }
+
+ if (temp & 0x04) {
+ result = -ENXIO;
+ dev_dbg(&vt596_adapter.dev, "No response\n");
+ }
+
+ /* Resetting status register */
+ if (temp & 0x1F)
+ outb_p(temp, SMBHSTSTS);
+
+ vt596_dump_regs("Transaction (post)", size);
+
+ return result;
+}
+
+/* Return negative errno on error, 0 on success */
+static s32 vt596_access(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ int i;
+ int status;
+
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ size = VT596_QUICK;
+ break;
+ case I2C_SMBUS_BYTE:
+ if (read_write == I2C_SMBUS_WRITE)
+ outb_p(command, SMBHSTCMD);
+ size = VT596_BYTE;
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ outb_p(command, SMBHSTCMD);
+ if (read_write == I2C_SMBUS_WRITE)
+ outb_p(data->byte, SMBHSTDAT0);
+ size = VT596_BYTE_DATA;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ outb_p(command, SMBHSTCMD);
+ if (read_write == I2C_SMBUS_WRITE) {
+ outb_p(data->word & 0xff, SMBHSTDAT0);
+ outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
+ }
+ size = VT596_WORD_DATA;
+ break;
+ case I2C_SMBUS_PROC_CALL:
+ outb_p(command, SMBHSTCMD);
+ outb_p(data->word & 0xff, SMBHSTDAT0);
+ outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
+ size = VT596_PROC_CALL;
+ break;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ if (!(vt596_features & FEATURE_I2CBLOCK))
+ goto exit_unsupported;
+ if (read_write == I2C_SMBUS_READ)
+ outb_p(data->block[0], SMBHSTDAT0);
+ fallthrough;
+ case I2C_SMBUS_BLOCK_DATA:
+ outb_p(command, SMBHSTCMD);
+ if (read_write == I2C_SMBUS_WRITE) {
+ u8 len = data->block[0];
+ if (len > I2C_SMBUS_BLOCK_MAX)
+ len = I2C_SMBUS_BLOCK_MAX;
+ outb_p(len, SMBHSTDAT0);
+ inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+ for (i = 1; i <= len; i++)
+ outb_p(data->block[i], SMBBLKDAT);
+ }
+ size = (size == I2C_SMBUS_I2C_BLOCK_DATA) ?
+ VT596_I2C_BLOCK_DATA : VT596_BLOCK_DATA;
+ break;
+ default:
+ goto exit_unsupported;
+ }
+
+ outb_p(((addr & 0x7f) << 1) | read_write, SMBHSTADD);
+
+ status = vt596_transaction(size);
+ if (status)
+ return status;
+
+ if (size == VT596_PROC_CALL)
+ read_write = I2C_SMBUS_READ;
+
+ if ((read_write == I2C_SMBUS_WRITE) || (size == VT596_QUICK))
+ return 0;
+
+ switch (size) {
+ case VT596_BYTE:
+ case VT596_BYTE_DATA:
+ data->byte = inb_p(SMBHSTDAT0);
+ break;
+ case VT596_WORD_DATA:
+ case VT596_PROC_CALL:
+ data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
+ break;
+ case VT596_I2C_BLOCK_DATA:
+ case VT596_BLOCK_DATA:
+ data->block[0] = inb_p(SMBHSTDAT0);
+ if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
+ data->block[0] = I2C_SMBUS_BLOCK_MAX;
+ inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
+ for (i = 1; i <= data->block[0]; i++)
+ data->block[i] = inb_p(SMBBLKDAT);
+ break;
+ }
+ return 0;
+
+exit_unsupported:
+ dev_warn(&vt596_adapter.dev, "Unsupported transaction %d\n",
+ size);
+ return -EOPNOTSUPP;
+}
+
+static u32 vt596_func(struct i2c_adapter *adapter)
+{
+ u32 func = I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_BLOCK_DATA;
+
+ if (vt596_features & FEATURE_I2CBLOCK)
+ func |= I2C_FUNC_SMBUS_I2C_BLOCK;
+ return func;
+}
+
+static const struct i2c_algorithm smbus_algorithm = {
+ .smbus_xfer = vt596_access,
+ .functionality = vt596_func,
+};
+
+static struct i2c_adapter vt596_adapter = {
+ .owner = THIS_MODULE,
+ .class = I2C_CLASS_HWMON | I2C_CLASS_SPD,
+ .algo = &smbus_algorithm,
+};
+
+static int vt596_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ unsigned char temp;
+ int error;
+
+ /* Determine the address of the SMBus areas */
+ if (force_addr) {
+ vt596_smba = force_addr & 0xfff0;
+ force = 0;
+ goto found;
+ }
+
+ if ((pci_read_config_word(pdev, id->driver_data, &vt596_smba)) ||
+ !(vt596_smba & 0x0001)) {
+ /* try 2nd address and config reg. for 596 */
+ if (id->device == PCI_DEVICE_ID_VIA_82C596_3 &&
+ !pci_read_config_word(pdev, SMBBA2, &vt596_smba) &&
+ (vt596_smba & 0x0001)) {
+ SMBHSTCFG = 0x84;
+ } else {
+ /* no matches at all */
+ dev_err(&pdev->dev, "Cannot configure "
+ "SMBus I/O Base address\n");
+ return -ENODEV;
+ }
+ }
+
+ vt596_smba &= 0xfff0;
+ if (vt596_smba == 0) {
+ dev_err(&pdev->dev, "SMBus base address "
+ "uninitialized - upgrade BIOS or use "
+ "force_addr=0xaddr\n");
+ return -ENODEV;
+ }
+
+found:
+ error = acpi_check_region(vt596_smba, 8, vt596_driver.name);
+ if (error)
+ return -ENODEV;
+
+ if (!request_region(vt596_smba, 8, vt596_driver.name)) {
+ dev_err(&pdev->dev, "SMBus region 0x%x already in use!\n",
+ vt596_smba);
+ return -ENODEV;
+ }
+
+ pci_read_config_byte(pdev, SMBHSTCFG, &temp);
+ /* If force_addr is set, we program the new address here. Just to make
+ sure, we disable the VT596 first. */
+ if (force_addr) {
+ pci_write_config_byte(pdev, SMBHSTCFG, temp & 0xfe);
+ pci_write_config_word(pdev, id->driver_data, vt596_smba);
+ pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01);
+ dev_warn(&pdev->dev, "WARNING: SMBus interface set to new "
+ "address 0x%04x!\n", vt596_smba);
+ } else if (!(temp & 0x01)) {
+ if (force) {
+ /* NOTE: This assumes I/O space and other allocations
+ * WERE done by the Bios! Don't complain if your
+ * hardware does weird things after enabling this.
+ * :') Check for Bios updates before resorting to
+ * this.
+ */
+ pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01);
+ dev_info(&pdev->dev, "Enabling SMBus device\n");
+ } else {
+ dev_err(&pdev->dev, "SMBUS: Error: Host SMBus "
+ "controller not enabled! - upgrade BIOS or "
+ "use force=1\n");
+ error = -ENODEV;
+ goto release_region;
+ }
+ }
+
+ dev_dbg(&pdev->dev, "VT596_smba = 0x%X\n", vt596_smba);
+
+ switch (pdev->device) {
+ case PCI_DEVICE_ID_VIA_CX700:
+ case PCI_DEVICE_ID_VIA_VX800:
+ case PCI_DEVICE_ID_VIA_VX855:
+ case PCI_DEVICE_ID_VIA_VX900:
+ case PCI_DEVICE_ID_VIA_8251:
+ case PCI_DEVICE_ID_VIA_8237:
+ case PCI_DEVICE_ID_VIA_8237A:
+ case PCI_DEVICE_ID_VIA_8237S:
+ case PCI_DEVICE_ID_VIA_8235:
+ case PCI_DEVICE_ID_VIA_8233A:
+ case PCI_DEVICE_ID_VIA_8233_0:
+ vt596_features |= FEATURE_I2CBLOCK;
+ break;
+ case PCI_DEVICE_ID_VIA_82C686_4:
+ /* The VT82C686B (rev 0x40) does support I2C block
+ transactions, but the VT82C686A (rev 0x30) doesn't */
+ if (pdev->revision >= 0x40)
+ vt596_features |= FEATURE_I2CBLOCK;
+ break;
+ }
+
+ vt596_adapter.dev.parent = &pdev->dev;
+ snprintf(vt596_adapter.name, sizeof(vt596_adapter.name),
+ "SMBus Via Pro adapter at %04x", vt596_smba);
+
+ vt596_pdev = pci_dev_get(pdev);
+ error = i2c_add_adapter(&vt596_adapter);
+ if (error) {
+ pci_dev_put(vt596_pdev);
+ vt596_pdev = NULL;
+ goto release_region;
+ }
+
+ /* Always return failure here. This is to allow other drivers to bind
+ * to this pci device. We don't really want to have control over the
+ * pci device, we only wanted to read as few register values from it.
+ */
+ return -ENODEV;
+
+release_region:
+ release_region(vt596_smba, 8);
+ return error;
+}
+
+static const struct pci_device_id vt596_ids[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596_3),
+ .driver_data = SMBBA1 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596B_3),
+ .driver_data = SMBBA1 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4),
+ .driver_data = SMBBA1 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233_0),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233A),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237A),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237S),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4),
+ .driver_data = SMBBA1 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8251),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_CX700),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX800),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX855),
+ .driver_data = SMBBA3 },
+ { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_VX900),
+ .driver_data = SMBBA3 },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, vt596_ids);
+
+static struct pci_driver vt596_driver = {
+ .name = "vt596_smbus",
+ .id_table = vt596_ids,
+ .probe = vt596_probe,
+};
+
+static int __init i2c_vt596_init(void)
+{
+ return pci_register_driver(&vt596_driver);
+}
+
+
+static void __exit i2c_vt596_exit(void)
+{
+ pci_unregister_driver(&vt596_driver);
+ if (vt596_pdev != NULL) {
+ i2c_del_adapter(&vt596_adapter);
+ release_region(vt596_smba, 8);
+ pci_dev_put(vt596_pdev);
+ vt596_pdev = NULL;
+ }
+}
+
+MODULE_AUTHOR("Kyosti Malkki <kmalkki@cc.hut.fi>");
+MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
+MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
+MODULE_DESCRIPTION("vt82c596 SMBus driver");
+MODULE_LICENSE("GPL");
+
+module_init(i2c_vt596_init);
+module_exit(i2c_vt596_exit);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-09 13:26:21 +0000