aboutsummaryrefslogtreecommitdiff
path: root/drivers/i2c/busses/i2c-s3c2410.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c/busses/i2c-s3c2410.c')
-rw-r--r--drivers/i2c/busses/i2c-s3c2410.c131
1 files changed, 122 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index f84a63c6dd9..4c171808168 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -35,6 +35,8 @@
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/io.h>
+#include <linux/of_i2c.h>
+#include <linux/of_gpio.h>
#include <asm/irq.h>
@@ -78,6 +80,8 @@ struct s3c24xx_i2c {
struct resource *ioarea;
struct i2c_adapter adap;
+ struct s3c2410_platform_i2c *pdata;
+ int gpios[2];
#ifdef CONFIG_CPU_FREQ
struct notifier_block freq_transition;
#endif
@@ -95,6 +99,12 @@ static inline int s3c24xx_i2c_is2440(struct s3c24xx_i2c *i2c)
struct platform_device *pdev = to_platform_device(i2c->dev);
enum s3c24xx_i2c_type type;
+#ifdef CONFIG_OF
+ if (i2c->dev->of_node)
+ return of_device_is_compatible(i2c->dev->of_node,
+ "samsung,s3c2440-i2c");
+#endif
+
type = platform_get_device_id(pdev)->driver_data;
return type == TYPE_S3C2440;
}
@@ -524,6 +534,7 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
/* first, try busy waiting briefly */
do {
+ cpu_relax();
iicstat = readl(i2c->regs + S3C2410_IICSTAT);
} while ((iicstat & S3C2410_IICSTAT_START) && --spins);
@@ -625,7 +636,7 @@ static int s3c24xx_i2c_calcdivisor(unsigned long clkin, unsigned int wanted,
static int s3c24xx_i2c_clockrate(struct s3c24xx_i2c *i2c, unsigned int *got)
{
- struct s3c2410_platform_i2c *pdata = i2c->dev->platform_data;
+ struct s3c2410_platform_i2c *pdata = i2c->pdata;
unsigned long clkin = clk_get_rate(i2c->clk);
unsigned int divs, div1;
unsigned long target_frequency;
@@ -741,6 +752,49 @@ static inline void s3c24xx_i2c_deregister_cpufreq(struct s3c24xx_i2c *i2c)
}
#endif
+#ifdef CONFIG_OF
+static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
+{
+ int idx, gpio, ret;
+
+ for (idx = 0; idx < 2; idx++) {
+ gpio = of_get_gpio(i2c->dev->of_node, idx);
+ if (!gpio_is_valid(gpio)) {
+ dev_err(i2c->dev, "invalid gpio[%d]: %d\n", idx, gpio);
+ goto free_gpio;
+ }
+
+ ret = gpio_request(gpio, "i2c-bus");
+ if (ret) {
+ dev_err(i2c->dev, "gpio [%d] request failed\n", gpio);
+ goto free_gpio;
+ }
+ }
+ return 0;
+
+free_gpio:
+ while (--idx >= 0)
+ gpio_free(i2c->gpios[idx]);
+ return -EINVAL;
+}
+
+static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
+{
+ unsigned int idx;
+ for (idx = 0; idx < 2; idx++)
+ gpio_free(i2c->gpios[idx]);
+}
+#else
+static int s3c24xx_i2c_parse_dt_gpio(struct s3c24xx_i2c *i2c)
+{
+ return 0;
+}
+
+static void s3c24xx_i2c_dt_gpio_free(struct s3c24xx_i2c *i2c)
+{
+}
+#endif
+
/* s3c24xx_i2c_init
*
* initialise the controller, set the IO lines and frequency
@@ -754,12 +808,15 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
/* get the plafrom data */
- pdata = i2c->dev->platform_data;
+ pdata = i2c->pdata;
/* inititalise the gpio */
if (pdata->cfg_gpio)
pdata->cfg_gpio(to_platform_device(i2c->dev));
+ else
+ if (s3c24xx_i2c_parse_dt_gpio(i2c))
+ return -EINVAL;
/* write slave address */
@@ -785,6 +842,34 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
return 0;
}
+#ifdef CONFIG_OF
+/* s3c24xx_i2c_parse_dt
+ *
+ * Parse the device tree node and retreive the platform data.
+*/
+
+static void
+s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c)
+{
+ struct s3c2410_platform_i2c *pdata = i2c->pdata;
+
+ if (!np)
+ return;
+
+ pdata->bus_num = -1; /* i2c bus number is dynamically assigned */
+ of_property_read_u32(np, "samsung,i2c-sda-delay", &pdata->sda_delay);
+ of_property_read_u32(np, "samsung,i2c-slave-addr", &pdata->slave_addr);
+ of_property_read_u32(np, "samsung,i2c-max-bus-freq",
+ (u32 *)&pdata->frequency);
+}
+#else
+static void
+s3c24xx_i2c_parse_dt(struct device_node *np, struct s3c24xx_i2c *i2c)
+{
+ return;
+}
+#endif
+
/* s3c24xx_i2c_probe
*
* called by the bus driver when a suitable device is found
@@ -793,14 +878,16 @@ static int s3c24xx_i2c_init(struct s3c24xx_i2c *i2c)
static int s3c24xx_i2c_probe(struct platform_device *pdev)
{
struct s3c24xx_i2c *i2c;
- struct s3c2410_platform_i2c *pdata;
+ struct s3c2410_platform_i2c *pdata = NULL;
struct resource *res;
int ret;
- pdata = pdev->dev.platform_data;
- if (!pdata) {
- dev_err(&pdev->dev, "no platform data\n");
- return -EINVAL;
+ if (!pdev->dev.of_node) {
+ pdata = pdev->dev.platform_data;
+ if (!pdata) {
+ dev_err(&pdev->dev, "no platform data\n");
+ return -EINVAL;
+ }
}
i2c = kzalloc(sizeof(struct s3c24xx_i2c), GFP_KERNEL);
@@ -809,6 +896,17 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
return -ENOMEM;
}
+ i2c->pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!i2c->pdata) {
+ ret = -ENOMEM;
+ goto err_noclk;
+ }
+
+ if (pdata)
+ memcpy(i2c->pdata, pdata, sizeof(*pdata));
+ else
+ s3c24xx_i2c_parse_dt(pdev->dev.of_node, i2c);
+
strlcpy(i2c->adap.name, "s3c2410-i2c", sizeof(i2c->adap.name));
i2c->adap.owner = THIS_MODULE;
i2c->adap.algo = &s3c24xx_i2c_algorithm;
@@ -883,7 +981,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
goto err_iomap;
}
- ret = request_irq(i2c->irq, s3c24xx_i2c_irq, IRQF_DISABLED,
+ ret = request_irq(i2c->irq, s3c24xx_i2c_irq, 0,
dev_name(&pdev->dev), i2c);
if (ret != 0) {
@@ -903,7 +1001,8 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
* being bus 0.
*/
- i2c->adap.nr = pdata->bus_num;
+ i2c->adap.nr = i2c->pdata->bus_num;
+ i2c->adap.dev.of_node = pdev->dev.of_node;
ret = i2c_add_numbered_adapter(&i2c->adap);
if (ret < 0) {
@@ -911,6 +1010,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
goto err_cpufreq;
}
+ of_i2c_register_devices(&i2c->adap);
platform_set_drvdata(pdev, i2c);
dev_info(&pdev->dev, "%s: S3C I2C adapter\n", dev_name(&i2c->adap.dev));
@@ -959,6 +1059,7 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
iounmap(i2c->regs);
release_resource(i2c->ioarea);
+ s3c24xx_i2c_dt_gpio_free(i2c);
kfree(i2c->ioarea);
kfree(i2c);
@@ -1012,6 +1113,17 @@ static struct platform_device_id s3c24xx_driver_ids[] = {
};
MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);
+#ifdef CONFIG_OF
+static const struct of_device_id s3c24xx_i2c_match[] = {
+ { .compatible = "samsung,s3c2410-i2c" },
+ { .compatible = "samsung,s3c2440-i2c" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, s3c24xx_i2c_match);
+#else
+#define s3c24xx_i2c_match NULL
+#endif
+
static struct platform_driver s3c24xx_i2c_driver = {
.probe = s3c24xx_i2c_probe,
.remove = s3c24xx_i2c_remove,
@@ -1020,6 +1132,7 @@ static struct platform_driver s3c24xx_i2c_driver = {
.owner = THIS_MODULE,
.name = "s3c-i2c",
.pm = S3C24XX_DEV_PM_OPS,
+ .of_match_table = s3c24xx_i2c_match,
},
};
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-14 09:18:57 +0000