This patch adds basic interrupt support to the i2c-i801 driver.
Signed-off-by: Ivo Manca <[EMAIL PROTECTED]>
---
--- i2c-i801.c.git 2008-07-03 15:47:32.000000000 +0200
+++ i2c-i801.c 2008-07-07 15:04:25.000000000 +0200
@@ -63,6 +63,7 @@
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/init.h>
+#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <asm/io.h>
@@ -100,6 +101,7 @@
/* I801 command constants */
#define I801_QUICK 0x00
+#define I801_HST_CNT_INTREN 0x01
#define I801_BYTE 0x04
#define I801_BYTE_DATA 0x08
#define I801_WORD_DATA 0x0C
@@ -121,23 +123,65 @@
#define SMBHSTSTS_INTR 0x02
#define SMBHSTSTS_HOST_BUSY 0x01
+/* mask for events we normally handle */
+#define I801_HST_STS_MASK_NORM ( \
+ SMBHSTSTS_FAILED | \
+ SMBHSTSTS_BUS_ERR | \
+ SMBHSTSTS_DEV_ERR | \
+ SMBHSTSTS_INTR)
+
+/* mask for all events */
+#define I801_HST_STS_MASK_ALL ( \
+ SMBHSTSTS_BYTE_DONE | \
+ SMBHSTSTS_SMBALERT_STS | \
+ SMBHSTSTS_FAILED | \
+ SMBHSTSTS_BUS_ERR | \
+ SMBHSTSTS_DEV_ERR | \
+ SMBHSTSTS_INTR)
+
static unsigned long i801_smba;
static unsigned char i801_original_hstcfg;
+static struct i2c_adapter i801_adapter;
static struct pci_driver i801_driver;
static struct pci_dev *I801_dev;
+struct i2c_i801_algo_data {
+ spinlock_t lock;
+ wait_queue_head_t waitq;
+ int status; /* copy of h/w register */
+ int irq;
+};
+
+static struct i2c_i801_algo_data i801_algo_data;
+
#define FEATURE_SMBUS_PEC (1 << 0)
#define FEATURE_BLOCK_BUFFER (1 << 1)
#define FEATURE_BLOCK_PROC (1 << 2)
#define FEATURE_I2C_BLOCK_READ (1 << 3)
static unsigned int i801_features;
+/* fetch & consume host status out of algo_data */
+static inline int i801_get_status(struct i2c_i801_algo_data *algo_data)
+{
+ unsigned long flags;
+ int status;
+
+ spin_lock_irqsave(&algo_data->lock, flags);
+ status = algo_data->status;
+ algo_data->status = 0;
+ spin_unlock_irqrestore(&algo_data->lock, flags);
+
+ return status;
+}
+
static int i801_transaction(int xact)
{
int temp;
int result = 0;
int timeout = 0;
+ struct i2c_i801_algo_data *algo_data = i801_adapter.algo_data;
+
dev_dbg(&I801_dev->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
@@ -159,6 +203,13 @@ static int i801_transaction(int xact)
/* the current contents of SMBHSTCNT can be overwritten, since PEC,
* INTREN, SMBSCMD are passed in xact */
+ if (algo_data->irq >= 0) {
+ outb_p(xact | I801_START | I801_HST_CNT_INTREN, SMBHSTCNT);
+
+ wait_event_interruptible_timeout(algo_data->waitq,
+ ((temp = i801_get_status(algo_data))
+ & I801_HST_STS_MASK_NORM), HZ/2);
+ } else {
outb_p(xact | I801_START, SMBHSTCNT);
/* We will always wait for a fraction of a second! */
@@ -177,6 +228,7 @@ static int i801_transaction(int xact)
msleep(1);
outb_p(inb_p(SMBHSTCNT) & (~SMBHSTCNT_KILL), SMBHSTCNT);
}
+ }
if (temp & SMBHSTSTS_FAILED) {
result = -1;
@@ -574,6 +626,7 @@ static struct i2c_adapter i801_adapter =
.id = I2C_HW_SMBUS_I801,
.class = I2C_CLASS_HWMON,
.algo = &smbus_algorithm,
+ .algo_data = &i801_algo_data
};
static struct pci_device_id i801_ids[] = {
@@ -597,8 +650,38 @@ static struct pci_device_id i801_ids[] =
MODULE_DEVICE_TABLE (pci, i801_ids);
+static irqreturn_t i801_isr(int irq, void *dev_id)
+{
+ u8 status = inb(SMBHSTSTS);
+
+ /* bail if it's not ours */
+ if (!(status & I801_HST_STS_MASK_ALL)) {
+ dev_dbg(&I801_dev->dev, "BAILING interrupt\n");
+ return IRQ_NONE;
+ }
+
+ dev_dbg(&I801_dev->dev, "INTERRUPT: IRQ status: 0x%02x\n", status);
+
+ /* ACK */
+ outb((status & I801_HST_STS_MASK_ALL), SMBHSTSTS);
+
+ if (status & I801_HST_STS_MASK_NORM) {
+ struct i2c_adapter *adap = dev_id;
+ struct i2c_i801_algo_data *algo_data = adap->algo_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&algo_data->lock, flags);
+ algo_data->status = status;
+ spin_unlock_irqrestore(&algo_data->lock, flags);
+ wake_up_interruptible(&algo_data->waitq);
+ }
+
+ return IRQ_HANDLED;
+}
+
static int __devinit i801_probe(struct pci_dev *dev, const struct
pci_device_id *id)
{
+ struct i2c_i801_algo_data *algo_data = i801_adapter.algo_data;
unsigned char temp;
int err;
@@ -656,10 +739,27 @@ static int __devinit i801_probe(struct p
}
pci_write_config_byte(I801_dev, SMBHSTCFG, temp);
- if (temp & SMBHSTCFG_SMB_SMI_EN)
+ if (temp & SMBHSTCFG_SMB_SMI_EN) {
dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
- else
+ algo_data->irq = -1;
+ } else {
dev_dbg(&dev->dev, "SMBus using PCI Interrupt\n");
+ if ((request_irq(I801_dev->irq, i801_isr, IRQF_SHARED,
+ i801_adapter.name, &i801_adapter))) {
+ dev_err(&dev->dev,
+ "request irq %d failed!\n", I801_dev->irq);
+ algo_data->irq = -1;
+ } else {
+ dev_dbg(&dev->dev,
+ "SMBus base address: 0x%04lx, IRQ: %d\n",
+ i801_smba, I801_dev->irq);
+
+ algo_data->irq = I801_dev->irq;
+ algo_data->status = 0;
+ init_waitqueue_head(&algo_data->waitq);
+ spin_lock_init(&algo_data->lock);
+ }
+ }
/* Clear special mode bits */
if (i801_features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
@@ -686,6 +786,10 @@ exit:
static void __devexit i801_remove(struct pci_dev *dev)
{
+ struct i2c_i801_algo_data *algo_data = i801_adapter.algo_data;
+ if (algo_data->irq >= 0)
+ free_irq(dev->irq, &i801_adapter);
+
i2c_del_adapter(&i801_adapter);
pci_write_config_byte(I801_dev, SMBHSTCFG, i801_original_hstcfg);
pci_release_region(dev, SMBBAR);
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