i2c: PA Semi SMBus driver
New driver for the PA Semi SMBus interfaces.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/i2c/busses/i2c-pasemi.c b/drivers/i2c/busses/i2c-pasemi.c
new file mode 100644
index 0000000..f54fb5d
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pasemi.c
@@ -0,0 +1,426 @@
+/*
+ * Copyright (C) 2006-2007 PA Semi, Inc
+ *
+ * SMBus host driver for PA Semi PWRficient
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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
+ */
+
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/sched.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+static struct pci_driver pasemi_smb_driver;
+
+struct pasemi_smbus {
+ struct pci_dev *dev;
+ struct i2c_adapter adapter;
+ unsigned long base;
+ int size;
+};
+
+/* Register offsets */
+#define REG_MTXFIFO 0x00
+#define REG_MRXFIFO 0x04
+#define REG_SMSTA 0x14
+#define REG_CTL 0x1c
+
+/* Register defs */
+#define MTXFIFO_READ 0x00000400
+#define MTXFIFO_STOP 0x00000200
+#define MTXFIFO_START 0x00000100
+#define MTXFIFO_DATA_M 0x000000ff
+
+#define MRXFIFO_EMPTY 0x00000100
+#define MRXFIFO_DATA_M 0x000000ff
+
+#define SMSTA_XEN 0x08000000
+
+#define CTL_MRR 0x00000400
+#define CTL_MTR 0x00000200
+#define CTL_CLK_M 0x000000ff
+
+#define CLK_100K_DIV 84
+#define CLK_400K_DIV 21
+
+static inline void reg_write(struct pasemi_smbus *smbus, int reg, int val)
+{
+ dev_dbg(&smbus->dev->dev, "smbus write reg %lx val %08x\n",
+ smbus->base + reg, val);
+ outl(val, smbus->base + reg);
+}
+
+static inline int reg_read(struct pasemi_smbus *smbus, int reg)
+{
+ int ret;
+ ret = inl(smbus->base + reg);
+ dev_dbg(&smbus->dev->dev, "smbus read reg %lx val %08x\n",
+ smbus->base + reg, ret);
+ return ret;
+}
+
+#define TXFIFO_WR(smbus, reg) reg_write((smbus), REG_MTXFIFO, (reg))
+#define RXFIFO_RD(smbus) reg_read((smbus), REG_MRXFIFO)
+
+static void pasemi_smb_clear(struct pasemi_smbus *smbus)
+{
+ unsigned int status;
+
+ status = reg_read(smbus, REG_SMSTA);
+ reg_write(smbus, REG_SMSTA, status);
+}
+
+static unsigned int pasemi_smb_waitready(struct pasemi_smbus *smbus)
+{
+ int timeout = 10;
+ unsigned int status;
+
+ status = reg_read(smbus, REG_SMSTA);
+
+ while (!(status & SMSTA_XEN) && timeout--) {
+ msleep(1);
+ status = reg_read(smbus, REG_SMSTA);
+ }
+
+ if (timeout < 0) {
+ dev_warn(&smbus->dev->dev, "Timeout, status 0x%08x\n", status);
+ reg_write(smbus, REG_SMSTA, status);
+ return -ETIME;
+ }
+
+ /* Clear XEN */
+ reg_write(smbus, REG_SMSTA, SMSTA_XEN);
+
+ return 0;
+}
+
+static int pasemi_i2c_xfer_msg(struct i2c_adapter *adapter,
+ struct i2c_msg *msg, int stop)
+{
+ struct pasemi_smbus *smbus = adapter->algo_data;
+ int read, i, err;
+ u32 rd;
+
+ read = msg->flags & I2C_M_RD ? 1 : 0;
+
+ TXFIFO_WR(smbus, MTXFIFO_START | (msg->addr << 1) | read);
+
+ if (read) {
+ TXFIFO_WR(smbus, msg->len | MTXFIFO_READ |
+ (stop ? MTXFIFO_STOP : 0));
+
+ err = pasemi_smb_waitready(smbus);
+ if (err)
+ goto reset_out;
+
+ for (i = 0; i < msg->len; i++) {
+ rd = RXFIFO_RD(smbus);
+ if (rd & MRXFIFO_EMPTY) {
+ err = -ENODATA;
+ goto reset_out;
+ }
+ msg->buf[i] = rd & MRXFIFO_DATA_M;
+ }
+ } else {
+ for (i = 0; i < msg->len - 1; i++)
+ TXFIFO_WR(smbus, msg->buf[i]);
+
+ TXFIFO_WR(smbus, msg->buf[msg->len] |
+ (stop ? MTXFIFO_STOP : 0));
+ }
+
+ return 0;
+
+ reset_out:
+ reg_write(smbus, REG_CTL, (CTL_MTR | CTL_MRR |
+ (CLK_100K_DIV & CTL_CLK_M)));
+ return err;
+}
+
+static int pasemi_i2c_xfer(struct i2c_adapter *adapter,
+ struct i2c_msg *msgs, int num)
+{
+ struct pasemi_smbus *smbus = adapter->algo_data;
+ int ret, i;
+
+ pasemi_smb_clear(smbus);
+
+ ret = 0;
+
+ for (i = 0; i < num && !ret; i++)
+ ret = pasemi_i2c_xfer_msg(adapter, &msgs[i], (i == (num - 1)));
+
+ return ret ? ret : num;
+}
+
+static int pasemi_smb_xfer(struct i2c_adapter *adapter,
+ u16 addr, unsigned short flags, char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct pasemi_smbus *smbus = adapter->algo_data;
+ unsigned int rd;
+ int read_flag, err;
+ int len = 0, i;
+
+ /* All our ops take 8-bit shifted addresses */
+ addr <<= 1;
+ read_flag = read_write == I2C_SMBUS_READ;
+
+ pasemi_smb_clear(smbus);
+
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ TXFIFO_WR(smbus, addr | read_flag | MTXFIFO_START |
+ MTXFIFO_STOP);
+ break;
+ case I2C_SMBUS_BYTE:
+ TXFIFO_WR(smbus, addr | read_flag | MTXFIFO_START);
+ if (read_write)
+ TXFIFO_WR(smbus, 1 | MTXFIFO_STOP | MTXFIFO_READ);
+ else
+ TXFIFO_WR(smbus, MTXFIFO_STOP | command);
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ TXFIFO_WR(smbus, addr | MTXFIFO_START);
+ TXFIFO_WR(smbus, command);
+ if (read_write) {
+ TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START);
+ TXFIFO_WR(smbus, 1 | MTXFIFO_READ | MTXFIFO_STOP);
+ } else {
+ TXFIFO_WR(smbus, MTXFIFO_STOP | data->byte);
+ }
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ TXFIFO_WR(smbus, addr | MTXFIFO_START);
+ TXFIFO_WR(smbus, command);
+ if (read_write) {
+ TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START);
+ TXFIFO_WR(smbus, 2 | MTXFIFO_READ | MTXFIFO_STOP);
+ } else {
+ TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M);
+ TXFIFO_WR(smbus, MTXFIFO_STOP | (data->word >> 8));
+ }
+ break;
+ case I2C_SMBUS_BLOCK_DATA:
+ TXFIFO_WR(smbus, addr | MTXFIFO_START);
+ TXFIFO_WR(smbus, command);
+ if (read_write) {
+ TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START);
+ TXFIFO_WR(smbus, 1 | MTXFIFO_READ);
+ rd = RXFIFO_RD(smbus);
+ len = min_t(u8, (rd & MRXFIFO_DATA_M),
+ I2C_SMBUS_BLOCK_MAX);
+ TXFIFO_WR(smbus, (len + 1) | MTXFIFO_READ |
+ MTXFIFO_STOP);
+ } else {
+ len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX);
+ TXFIFO_WR(smbus, len);
+ for (i = 1; i < len; i++)
+ TXFIFO_WR(smbus, data->block[i]);
+ TXFIFO_WR(smbus, data->block[len] | MTXFIFO_STOP);
+ }
+ break;
+ case I2C_SMBUS_PROC_CALL:
+ read_write = I2C_SMBUS_READ;
+ TXFIFO_WR(smbus, addr | MTXFIFO_START);
+ TXFIFO_WR(smbus, command);
+ TXFIFO_WR(smbus, data->word & MTXFIFO_DATA_M);
+ TXFIFO_WR(smbus, (data->word >> 8) & MTXFIFO_DATA_M);
+ TXFIFO_WR(smbus, addr | I2C_SMBUS_READ | MTXFIFO_START);
+ TXFIFO_WR(smbus, 2 | MTXFIFO_STOP | MTXFIFO_READ);
+ break;
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ len = min_t(u8, data->block[0], I2C_SMBUS_BLOCK_MAX - 1);
+ read_write = I2C_SMBUS_READ;
+ TXFIFO_WR(smbus, addr | MTXFIFO_START);
+ TXFIFO_WR(smbus, command);
+ TXFIFO_WR(smbus, len);
+ for (i = 1; i <= len; i++)
+ TXFIFO_WR(smbus, data->block[i]);
+ TXFIFO_WR(smbus, addr | I2C_SMBUS_READ);
+ TXFIFO_WR(smbus, MTXFIFO_READ | 1);
+ rd = RXFIFO_RD(smbus);
+ len = min_t(u8, (rd & MRXFIFO_DATA_M),
+ I2C_SMBUS_BLOCK_MAX - len);
+ TXFIFO_WR(smbus, (len + 1) | MTXFIFO_READ | MTXFIFO_STOP);
+ break;
+
+ default:
+ dev_warn(&adapter->dev, "Unsupported transaction %d\n", size);
+ return -EINVAL;
+ }
+
+ err = pasemi_smb_waitready(smbus);
+ if (err)
+ goto reset_out;
+
+ if (read_write == I2C_SMBUS_WRITE)
+ return 0;
+
+ switch (size) {
+ case I2C_SMBUS_BYTE:
+ case I2C_SMBUS_BYTE_DATA:
+ rd = RXFIFO_RD(smbus);
+ if (rd & MRXFIFO_EMPTY) {
+ err = -ENODATA;
+ goto reset_out;
+ }
+ data->byte = rd & MRXFIFO_DATA_M;
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_PROC_CALL:
+ rd = RXFIFO_RD(smbus);
+ if (rd & MRXFIFO_EMPTY) {
+ err = -ENODATA;
+ goto reset_out;
+ }
+ data->word = rd & MRXFIFO_DATA_M;
+ rd = RXFIFO_RD(smbus);
+ if (rd & MRXFIFO_EMPTY) {
+ err = -ENODATA;
+ goto reset_out;
+ }
+ data->word |= (rd & MRXFIFO_DATA_M) << 8;
+ break;
+ case I2C_SMBUS_BLOCK_DATA:
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ data->block[0] = len;
+ for (i = 1; i <= len; i ++) {
+ rd = RXFIFO_RD(smbus);
+ if (rd & MRXFIFO_EMPTY) {
+ err = -ENODATA;
+ goto reset_out;
+ }
+ data->block[i] = rd & MRXFIFO_DATA_M;
+ }
+ break;
+ }
+
+ return 0;
+
+ reset_out:
+ reg_write(smbus, REG_CTL, (CTL_MTR | CTL_MRR |
+ (CLK_100K_DIV & CTL_CLK_M)));
+ return err;
+}
+
+static u32 pasemi_smb_func(struct i2c_adapter *adapter)
+{
+ 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_I2C;
+}
+
+static const struct i2c_algorithm smbus_algorithm = {
+ .master_xfer = pasemi_i2c_xfer,
+ .smbus_xfer = pasemi_smb_xfer,
+ .functionality = pasemi_smb_func,
+};
+
+static int __devinit pasemi_smb_probe(struct pci_dev *dev,
+ const struct pci_device_id *id)
+{
+ struct pasemi_smbus *smbus;
+ int error;
+
+ if (!(pci_resource_flags(dev, 0) & IORESOURCE_IO))
+ return -ENODEV;
+
+ smbus = kzalloc(sizeof(struct pasemi_smbus), GFP_KERNEL);
+ if (!smbus)
+ return -ENOMEM;
+
+ smbus->dev = dev;
+ smbus->base = pci_resource_start(dev, 0);
+ smbus->size = pci_resource_len(dev, 0);
+
+ if (!request_region(smbus->base, smbus->size,
+ pasemi_smb_driver.name)) {
+ error = -EBUSY;
+ goto out_kfree;
+ }
+
+ smbus->adapter.owner = THIS_MODULE;
+ snprintf(smbus->adapter.name, I2C_NAME_SIZE,
+ "PA Semi SMBus adapter at 0x%lx", smbus->base);
+ smbus->adapter.class = I2C_CLASS_HWMON;
+ smbus->adapter.algo = &smbus_algorithm;
+ smbus->adapter.algo_data = smbus;
+
+ /* set up the driverfs linkage to our parent device */
+ smbus->adapter.dev.parent = &dev->dev;
+
+ reg_write(smbus, REG_CTL, (CTL_MTR | CTL_MRR |
+ (CLK_100K_DIV & CTL_CLK_M)));
+
+ error = i2c_add_adapter(&smbus->adapter);
+ if (error)
+ goto out_release_region;
+
+ pci_set_drvdata(dev, smbus);
+
+ return 0;
+
+ out_release_region:
+ release_region(smbus->base, smbus->size);
+ out_kfree:
+ kfree(smbus);
+ return error;
+}
+
+static void __devexit pasemi_smb_remove(struct pci_dev *dev)
+{
+ struct pasemi_smbus *smbus = pci_get_drvdata(dev);
+
+ i2c_del_adapter(&smbus->adapter);
+ release_region(smbus->base, smbus->size);
+ kfree(smbus);
+}
+
+static struct pci_device_id pasemi_smb_ids[] = {
+ { PCI_DEVICE(0x1959, 0xa003) },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, pasemi_smb_ids);
+
+static struct pci_driver pasemi_smb_driver = {
+ .name = "i2c-pasemi",
+ .id_table = pasemi_smb_ids,
+ .probe = pasemi_smb_probe,
+ .remove = __devexit_p(pasemi_smb_remove),
+};
+
+static int __init pasemi_smb_init(void)
+{
+ return pci_register_driver(&pasemi_smb_driver);
+}
+
+static void __exit pasemi_smb_exit(void)
+{
+ pci_unregister_driver(&pasemi_smb_driver);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR ("Olof Johansson <olof@lixom.net>");
+MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver");
+
+module_init(pasemi_smb_init);
+module_exit(pasemi_smb_exit);