#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>
-#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/err.h>
unsigned int msg_idx;
unsigned int msg_ptr;
+ unsigned int tx_setup;
+
enum s3c24xx_i2c_state state;
void __iomem *regs;
dev_dbg(i2c->dev, "START: %08lx to IICSTAT, %02x to DS\n", stat, addr);
writeb(addr, i2c->regs + S3C2410_IICDS);
- // delay a bit and reset iiccon before setting start (per samsung)
- udelay(1);
+ /* delay here to ensure the data byte has gotten onto the bus
+ * before the transaction is started */
+
+ ndelay(i2c->tx_setup);
+
dev_dbg(i2c->dev, "iiccon, %08lx\n", iiccon);
writel(iiccon, i2c->regs + S3C2410_IICCON);
if (!is_msgend(i2c)) {
byte = i2c->msg->buf[i2c->msg_ptr++];
writeb(byte, i2c->regs + S3C2410_IICDS);
-
+
+ /* delay after writing the byte to allow the
+ * data setup time on the bus, as writing the
+ * data to the register causes the first bit
+ * to appear on SDA, and SCL will change as
+ * soon as the interrupt is acknowledged */
+
+ ndelay(i2c->tx_setup);
+
} else if (!is_lastmsg(i2c)) {
/* we need to go to the next i2c message */
* top level IRQ servicing routine
*/
-static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id,
- struct pt_regs *regs)
+static irqreturn_t s3c24xx_i2c_irq(int irqno, void *dev_id)
{
struct s3c24xx_i2c *i2c = dev_id;
unsigned long status;
/* i2c bus registration info */
-static struct i2c_algorithm s3c24xx_i2c_algorithm = {
+static const struct i2c_algorithm s3c24xx_i2c_algorithm = {
.master_xfer = s3c24xx_i2c_xfer,
.functionality = s3c24xx_i2c_func,
};
static struct s3c24xx_i2c s3c24xx_i2c = {
- .lock = SPIN_LOCK_UNLOCKED,
- .wait = __WAIT_QUEUE_HEAD_INITIALIZER(s3c24xx_i2c.wait),
- .adap = {
+ .lock = __SPIN_LOCK_UNLOCKED(s3c24xx_i2c.lock),
+ .wait = __WAIT_QUEUE_HEAD_INITIALIZER(s3c24xx_i2c.wait),
+ .tx_setup = 50,
+ .adap = {
.name = "s3c2410-i2c",
.owner = THIS_MODULE,
.algo = &s3c24xx_i2c_algorithm,
return 0;
}
-static void s3c24xx_i2c_free(struct s3c24xx_i2c *i2c)
-{
- if (i2c->clk != NULL && !IS_ERR(i2c->clk)) {
- clk_disable(i2c->clk);
- clk_put(i2c->clk);
- i2c->clk = NULL;
- }
-
- if (i2c->regs != NULL) {
- iounmap(i2c->regs);
- i2c->regs = NULL;
- }
-
- if (i2c->ioarea != NULL) {
- release_resource(i2c->ioarea);
- kfree(i2c->ioarea);
- i2c->ioarea = NULL;
- }
-}
-
/* s3c24xx_i2c_probe
*
* called by the bus driver when a suitable device is found
if (IS_ERR(i2c->clk)) {
dev_err(&pdev->dev, "cannot get clock\n");
ret = -ENOENT;
- goto out;
+ goto err_noclk;
}
dev_dbg(&pdev->dev, "clock source %p\n", i2c->clk);
if (res == NULL) {
dev_err(&pdev->dev, "cannot find IO resource\n");
ret = -ENOENT;
- goto out;
+ goto err_clk;
}
i2c->ioarea = request_mem_region(res->start, (res->end-res->start)+1,
if (i2c->ioarea == NULL) {
dev_err(&pdev->dev, "cannot request IO\n");
ret = -ENXIO;
- goto out;
+ goto err_clk;
}
i2c->regs = ioremap(res->start, (res->end-res->start)+1);
if (i2c->regs == NULL) {
dev_err(&pdev->dev, "cannot map IO\n");
ret = -ENXIO;
- goto out;
+ goto err_ioarea;
}
dev_dbg(&pdev->dev, "registers %p (%p, %p)\n", i2c->regs, i2c->ioarea, res);
ret = s3c24xx_i2c_init(i2c);
if (ret != 0)
- goto out;
+ goto err_iomap;
/* find the IRQ for this unit (note, this relies on the init call to
* ensure no current IRQs pending
if (res == NULL) {
dev_err(&pdev->dev, "cannot find IRQ\n");
ret = -ENOENT;
- goto out;
+ goto err_iomap;
}
- ret = request_irq(res->start, s3c24xx_i2c_irq, SA_INTERRUPT,
+ ret = request_irq(res->start, s3c24xx_i2c_irq, IRQF_DISABLED,
pdev->name, i2c);
if (ret != 0) {
dev_err(&pdev->dev, "cannot claim IRQ\n");
- goto out;
+ goto err_iomap;
}
i2c->irq = res;
- dev_dbg(&pdev->dev, "irq resource %p (%ld)\n", res, res->start);
+ dev_dbg(&pdev->dev, "irq resource %p (%lu)\n", res,
+ (unsigned long)res->start);
ret = i2c_add_adapter(&i2c->adap);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add bus to i2c core\n");
- goto out;
+ goto err_irq;
}
platform_set_drvdata(pdev, i2c);
dev_info(&pdev->dev, "%s: S3C I2C adapter\n", i2c->adap.dev.bus_id);
+ return 0;
- out:
- if (ret < 0)
- s3c24xx_i2c_free(i2c);
+ err_irq:
+ free_irq(i2c->irq->start, i2c);
+
+ err_iomap:
+ iounmap(i2c->regs);
+ err_ioarea:
+ release_resource(i2c->ioarea);
+ kfree(i2c->ioarea);
+
+ err_clk:
+ clk_disable(i2c->clk);
+ clk_put(i2c->clk);
+
+ err_noclk:
return ret;
}
static int s3c24xx_i2c_remove(struct platform_device *pdev)
{
struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
-
- if (i2c != NULL) {
- s3c24xx_i2c_free(i2c);
- platform_set_drvdata(pdev, NULL);
- }
+
+ i2c_del_adapter(&i2c->adap);
+ free_irq(i2c->irq->start, i2c);
+
+ clk_disable(i2c->clk);
+ clk_put(i2c->clk);
+
+ iounmap(i2c->regs);
+
+ release_resource(i2c->ioarea);
+ kfree(i2c->ioarea);
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff