/* linux/drivers/i2c/busses/i2c-s3c2410.c
*
- * Copyright (C) 2004,2005 Simtec Electronics
+ * Copyright (C) 2004,2005,2009 Simtec Electronics
* Ben Dooks <ben@simtec.co.uk>
*
* S3C2410 I2C Controller
STATE_STOP
};
+enum s3c24xx_i2c_type {
+ TYPE_S3C2410,
+ TYPE_S3C2440,
+};
+
struct s3c24xx_i2c {
spinlock_t lock;
wait_queue_head_t wait;
static inline int s3c24xx_i2c_is2440(struct s3c24xx_i2c *i2c)
{
struct platform_device *pdev = to_platform_device(i2c->dev);
+ enum s3c24xx_i2c_type type;
- return !strcmp(pdev->name, "s3c2440-i2c");
+ type = platform_get_device_id(pdev)->driver_data;
+ return type == TYPE_S3C2440;
}
/* s3c24xx_i2c_master_complete
return clkin / (calc_divs * calc_div1);
}
-/* freq_acceptable
- *
- * test wether a frequency is within the acceptable range of error
-*/
-
-static inline int freq_acceptable(unsigned int freq, unsigned int wanted)
-{
- int diff = freq - wanted;
-
- return diff >= -2 && diff <= 2;
-}
-
/* s3c24xx_i2c_clockrate
*
* work out a divisor for the user requested frequency setting,
struct s3c2410_platform_i2c *pdata = i2c->dev->platform_data;
unsigned long clkin = clk_get_rate(i2c->clk);
unsigned int divs, div1;
+ unsigned long target_frequency;
u32 iiccon;
int freq;
- int start, end;
i2c->clkrate = clkin;
clkin /= 1000; /* clkin now in KHz */
- dev_dbg(i2c->dev, "pdata %p, freq %lu %lu..%lu\n",
- pdata, pdata->bus_freq, pdata->min_freq, pdata->max_freq);
+ dev_dbg(i2c->dev, "pdata desired frequency %lu\n", pdata->frequency);
- if (pdata->bus_freq != 0) {
- freq = s3c24xx_i2c_calcdivisor(clkin, pdata->bus_freq/1000,
- &div1, &divs);
- if (freq_acceptable(freq, pdata->bus_freq/1000))
- goto found;
- }
-
- /* ok, we may have to search for something suitable... */
+ target_frequency = pdata->frequency ? pdata->frequency : 100000;
- start = (pdata->max_freq == 0) ? pdata->bus_freq : pdata->max_freq;
- end = pdata->min_freq;
+ target_frequency /= 1000; /* Target frequency now in KHz */
- start /= 1000;
- end /= 1000;
+ freq = s3c24xx_i2c_calcdivisor(clkin, target_frequency, &div1, &divs);
- /* search loop... */
-
- for (; start > end; start--) {
- freq = s3c24xx_i2c_calcdivisor(clkin, start, &div1, &divs);
- if (freq_acceptable(freq, start))
- goto found;
+ if (freq > target_frequency) {
+ dev_err(i2c->dev,
+ "Unable to achieve desired frequency %luKHz." \
+ " Lowest achievable %dKHz\n", target_frequency, freq);
+ return -EINVAL;
}
- /* cannot find frequency spec */
-
- return -EINVAL;
-
- found:
*got = freq;
iiccon = readl(i2c->regs + S3C2410_IICCON);
dev_info(i2c->dev, "bus frequency set to %d KHz\n", freq);
dev_dbg(i2c->dev, "S3C2410_IICCON=0x%02lx\n", iicon);
- /* check for s3c2440 i2c controller */
-
- if (s3c24xx_i2c_is2440(i2c))
- writel(0x0, i2c->regs + S3C2440_IICLC);
-
return 0;
}
goto err_clk;
}
- i2c->ioarea = request_mem_region(res->start, (res->end-res->start)+1,
+ i2c->ioarea = request_mem_region(res->start, resource_size(res),
pdev->name);
if (i2c->ioarea == NULL) {
goto err_clk;
}
- i2c->regs = ioremap(res->start, (res->end-res->start)+1);
+ i2c->regs = ioremap(res->start, resource_size(res));
if (i2c->regs == NULL) {
dev_err(&pdev->dev, "cannot map IO\n");
}
#ifdef CONFIG_PM
-static int s3c24xx_i2c_suspend_late(struct platform_device *dev,
- pm_message_t msg)
+static int s3c24xx_i2c_suspend_noirq(struct device *dev)
{
- struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
+ struct platform_device *pdev = to_platform_device(dev);
+ struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
+
i2c->suspended = 1;
+
return 0;
}
-static int s3c24xx_i2c_resume(struct platform_device *dev)
+static int s3c24xx_i2c_resume(struct device *dev)
{
- struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
+ struct platform_device *pdev = to_platform_device(dev);
+ struct s3c24xx_i2c *i2c = platform_get_drvdata(pdev);
i2c->suspended = 0;
s3c24xx_i2c_init(i2c);
return 0;
}
+static const struct dev_pm_ops s3c24xx_i2c_dev_pm_ops = {
+ .suspend_noirq = s3c24xx_i2c_suspend_noirq,
+ .resume = s3c24xx_i2c_resume,
+};
+
+#define S3C24XX_DEV_PM_OPS (&s3c24xx_i2c_dev_pm_ops)
#else
-#define s3c24xx_i2c_suspend_late NULL
-#define s3c24xx_i2c_resume NULL
+#define S3C24XX_DEV_PM_OPS NULL
#endif
/* device driver for platform bus bits */
-static struct platform_driver s3c2410_i2c_driver = {
- .probe = s3c24xx_i2c_probe,
- .remove = s3c24xx_i2c_remove,
- .suspend_late = s3c24xx_i2c_suspend_late,
- .resume = s3c24xx_i2c_resume,
- .driver = {
- .owner = THIS_MODULE,
- .name = "s3c2410-i2c",
- },
+static struct platform_device_id s3c24xx_driver_ids[] = {
+ {
+ .name = "s3c2410-i2c",
+ .driver_data = TYPE_S3C2410,
+ }, {
+ .name = "s3c2440-i2c",
+ .driver_data = TYPE_S3C2440,
+ }, { },
};
+MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
-static struct platform_driver s3c2440_i2c_driver = {
+static struct platform_driver s3c24xx_i2c_driver = {
.probe = s3c24xx_i2c_probe,
.remove = s3c24xx_i2c_remove,
- .suspend_late = s3c24xx_i2c_suspend_late,
- .resume = s3c24xx_i2c_resume,
+ .id_table = s3c24xx_driver_ids,
.driver = {
.owner = THIS_MODULE,
- .name = "s3c2440-i2c",
+ .name = "s3c-i2c",
+ .pm = S3C24XX_DEV_PM_OPS,
},
};
static int __init i2c_adap_s3c_init(void)
{
- int ret;
-
- ret = platform_driver_register(&s3c2410_i2c_driver);
- if (ret == 0) {
- ret = platform_driver_register(&s3c2440_i2c_driver);
- if (ret)
- platform_driver_unregister(&s3c2410_i2c_driver);
- }
-
- return ret;
+ return platform_driver_register(&s3c24xx_i2c_driver);
}
+subsys_initcall(i2c_adap_s3c_init);
static void __exit i2c_adap_s3c_exit(void)
{
- platform_driver_unregister(&s3c2410_i2c_driver);
- platform_driver_unregister(&s3c2440_i2c_driver);
+ platform_driver_unregister(&s3c24xx_i2c_driver);
}
-
-module_init(i2c_adap_s3c_init);
module_exit(i2c_adap_s3c_exit);
MODULE_DESCRIPTION("S3C24XX I2C Bus driver");
MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
-MODULE_ALIAS("platform:s3c2410-i2c");
-MODULE_ALIAS("platform:s3c2440-i2c");