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authorBen Dooks <ben-linux@fluff.org>2011-01-12 23:24:51 +0100
committerBen Dooks <ben-linux@fluff.org>2011-01-12 23:24:51 +0100
commitc5ba47ba7f3810adf4974ed4fe7134327333130d (patch)
tree59866b36bfbfc1a763b3c0e1354ed0119a711e91 /drivers/i2c
parentMerge branch 'for-2638/i2c/iop' into for-linus/i2c-2638 (diff)
parenti2c-ocores: add some device tree documentation (diff)
downloadlinux-c5ba47ba7f3810adf4974ed4fe7134327333130d.tar.xz
linux-c5ba47ba7f3810adf4974ed4fe7134327333130d.zip
Merge branch 'for-2638/i2c/ocores' into for-linus/i2c-2638
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-ocores.c145
1 files changed, 102 insertions, 43 deletions
diff --git a/drivers/i2c/busses/i2c-ocores.c b/drivers/i2c/busses/i2c-ocores.c
index 0070371b29f3..ef3bcb1ce864 100644
--- a/drivers/i2c/busses/i2c-ocores.c
+++ b/drivers/i2c/busses/i2c-ocores.c
@@ -9,6 +9,41 @@
* kind, whether express or implied.
*/
+/*
+ * Device tree configuration:
+ *
+ * Required properties:
+ * - compatible : "opencores,i2c-ocores"
+ * - reg : bus address start and address range size of device
+ * - interrupts : interrupt number
+ * - regstep : size of device registers in bytes
+ * - clock-frequency : frequency of bus clock in Hz
+ *
+ * Example:
+ *
+ * i2c0: ocores@a0000000 {
+ * compatible = "opencores,i2c-ocores";
+ * reg = <0xa0000000 0x8>;
+ * interrupts = <10>;
+ *
+ * regstep = <1>;
+ * clock-frequency = <20000000>;
+ *
+ * -- Devices connected on this I2C bus get
+ * -- defined here; address- and size-cells
+ * -- apply to these child devices
+ *
+ * #address-cells = <1>;
+ * #size-cells = <0>;
+ *
+ * dummy@60 {
+ * compatible = "dummy";
+ * reg = <60>;
+ * };
+ * };
+ *
+ */
+
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
@@ -210,6 +245,32 @@ static struct i2c_adapter ocores_adapter = {
.algo = &ocores_algorithm,
};
+#ifdef CONFIG_OF
+static int ocores_i2c_of_probe(struct platform_device* pdev,
+ struct ocores_i2c* i2c)
+{
+ __be32* val;
+
+ val = of_get_property(pdev->dev.of_node, "regstep", NULL);
+ if (!val) {
+ dev_err(&pdev->dev, "Missing required parameter 'regstep'");
+ return -ENODEV;
+ }
+ i2c->regstep = be32_to_cpup(val);
+
+ val = of_get_property(pdev->dev.of_node, "clock-frequency", NULL);
+ if (!val) {
+ dev_err(&pdev->dev,
+ "Missing required parameter 'clock-frequency'");
+ return -ENODEV;
+ }
+ i2c->clock_khz = be32_to_cpup(val) / 1000;
+
+ return 0;
+}
+#else
+#define ocores_i2c_of_probe(pdev,i2c) -ENODEV
+#endif
static int __devinit ocores_i2c_probe(struct platform_device *pdev)
{
@@ -227,37 +288,41 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
if (!res2)
return -ENODEV;
- pdata = (struct ocores_i2c_platform_data*) pdev->dev.platform_data;
- if (!pdata)
- return -ENODEV;
-
- i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
+ i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
if (!i2c)
return -ENOMEM;
- if (!request_mem_region(res->start, resource_size(res),
- pdev->name)) {
+ if (!devm_request_mem_region(&pdev->dev, res->start,
+ resource_size(res), pdev->name)) {
dev_err(&pdev->dev, "Memory region busy\n");
- ret = -EBUSY;
- goto request_mem_failed;
+ return -EBUSY;
}
- i2c->base = ioremap(res->start, resource_size(res));
+ i2c->base = devm_ioremap_nocache(&pdev->dev, res->start,
+ resource_size(res));
if (!i2c->base) {
dev_err(&pdev->dev, "Unable to map registers\n");
- ret = -EIO;
- goto map_failed;
+ return -EIO;
+ }
+
+ pdata = pdev->dev.platform_data;
+ if (pdata) {
+ i2c->regstep = pdata->regstep;
+ i2c->clock_khz = pdata->clock_khz;
+ } else {
+ ret = ocores_i2c_of_probe(pdev, i2c);
+ if (ret)
+ return ret;
}
- i2c->regstep = pdata->regstep;
- i2c->clock_khz = pdata->clock_khz;
ocores_init(i2c);
init_waitqueue_head(&i2c->wait);
- ret = request_irq(res2->start, ocores_isr, 0, pdev->name, i2c);
+ ret = devm_request_irq(&pdev->dev, res2->start, ocores_isr, 0,
+ pdev->name, i2c);
if (ret) {
dev_err(&pdev->dev, "Cannot claim IRQ\n");
- goto request_irq_failed;
+ return ret;
}
/* hook up driver to tree */
@@ -265,36 +330,29 @@ static int __devinit ocores_i2c_probe(struct platform_device *pdev)
i2c->adap = ocores_adapter;
i2c_set_adapdata(&i2c->adap, i2c);
i2c->adap.dev.parent = &pdev->dev;
+#ifdef CONFIG_OF
+ i2c->adap.dev.of_node = pdev->dev.of_node;
+#endif
/* add i2c adapter to i2c tree */
ret = i2c_add_adapter(&i2c->adap);
if (ret) {
dev_err(&pdev->dev, "Failed to add adapter\n");
- goto add_adapter_failed;
+ return ret;
}
/* add in known devices to the bus */
- for (i = 0; i < pdata->num_devices; i++)
- i2c_new_device(&i2c->adap, pdata->devices + i);
+ if (pdata) {
+ for (i = 0; i < pdata->num_devices; i++)
+ i2c_new_device(&i2c->adap, pdata->devices + i);
+ }
return 0;
-
-add_adapter_failed:
- free_irq(res2->start, i2c);
-request_irq_failed:
- iounmap(i2c->base);
-map_failed:
- release_mem_region(res->start, resource_size(res));
-request_mem_failed:
- kfree(i2c);
-
- return ret;
}
static int __devexit ocores_i2c_remove(struct platform_device* pdev)
{
struct ocores_i2c *i2c = platform_get_drvdata(pdev);
- struct resource *res;
/* disable i2c logic */
oc_setreg(i2c, OCI2C_CONTROL, oc_getreg(i2c, OCI2C_CONTROL)
@@ -304,18 +362,6 @@ static int __devexit ocores_i2c_remove(struct platform_device* pdev)
i2c_del_adapter(&i2c->adap);
platform_set_drvdata(pdev, NULL);
- res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (res)
- free_irq(res->start, i2c);
-
- iounmap(i2c->base);
-
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (res)
- release_mem_region(res->start, resource_size(res));
-
- kfree(i2c);
-
return 0;
}
@@ -344,6 +390,16 @@ static int ocores_i2c_resume(struct platform_device *pdev)
#define ocores_i2c_resume NULL
#endif
+#ifdef CONFIG_OF
+static struct of_device_id ocores_i2c_match[] = {
+ {
+ .compatible = "opencores,i2c-ocores",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ocores_i2c_match);
+#endif
+
/* work with hotplug and coldplug */
MODULE_ALIAS("platform:ocores-i2c");
@@ -355,6 +411,9 @@ static struct platform_driver ocores_i2c_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "ocores-i2c",
+#ifdef CONFIG_OF
+ .of_match_table = ocores_i2c_match,
+#endif
},
};