i2c-imx: add device tree probe support

It adds device tree probe support for i2c-imx driver.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Darius Augulis <augulis.darius@gmail.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

diff --git a/Documentation/devicetree/bindings/i2c/fsl-imx-i2c.txt b/Documentation/devicetree/bindings/i2c/fsl-imx-i2c.txt
new file mode 100644 (file)
index 0000000..f3cf43b
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/fsl-imx-i2c.txt
@@ -0,0 +1,25 @@
+* Freescale Inter IC (I2C) and High Speed Inter IC (HS-I2C) for i.MX
+
+Required properties:
+- compatible : Should be "fsl,<chip>-i2c"
+- reg : Should contain I2C/HS-I2C registers location and length
+- interrupts : Should contain I2C/HS-I2C interrupt
+
+Optional properties:
+- clock-frequency : Constains desired I2C/HS-I2C bus clock frequency in Hz.
+  The absence of the propoerty indicates the default frequency 100 kHz.
+
+Examples:
+
+i2c@83fc4000 { /* I2C2 on i.MX51 */
+       compatible = "fsl,imx51-i2c", "fsl,imx1-i2c";
+       reg = <0x83fc4000 0x4000>;
+       interrupts = <63>;
+};
+
+i2c@70038000 { /* HS-I2C on i.MX51 */
+       compatible = "fsl,imx51-i2c", "fsl,imx1-i2c";
+       reg = <0x70038000 0x4000>;
+       interrupts = <64>;
+       clock-frequency = <400000>;
+};

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 54d809ed20bee78b0b96371026c6122dd1b66d19..58832e578fff24dbbff08b38eb82e093a2cf36df 100644 (file)
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -48,6 +48,9 @@
 #include <linux/platform_device.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_i2c.h>
 
 #include <mach/irqs.h>
 #include <mach/hardware.h>
@@ -125,6 +128,11 @@ struct imx_i2c_struct {
        unsigned int            ifdr; /* IMX_I2C_IFDR */
 };
 
+static const struct of_device_id i2c_imx_dt_ids[] = {
+       { .compatible = "fsl,imx1-i2c", },
+       { /* sentinel */ }
+};
+
 /** Functions for IMX I2C adapter driver ***************************************
 *******************************************************************************/
 
@@ -469,7 +477,7 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
        struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
        void __iomem *base;
        resource_size_t res_size;
-       int irq;
+       int irq, bitrate;
        int ret;
 
        dev_dbg(&pdev->dev, "<%s>\n", __func__);
@@ -512,6 +520,7 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
        i2c_imx->adapter.algo           = &i2c_imx_algo;
        i2c_imx->adapter.dev.parent     = &pdev->dev;
        i2c_imx->adapter.nr             = pdev->id;
+       i2c_imx->adapter.dev.of_node    = pdev->dev.of_node;
        i2c_imx->irq                    = irq;
        i2c_imx->base                   = base;
        i2c_imx->res                    = res;
@@ -538,10 +547,12 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
        i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
 
        /* Set up clock divider */
-       if (pdata && pdata->bitrate)
-               i2c_imx_set_clk(i2c_imx, pdata->bitrate);
-       else
-               i2c_imx_set_clk(i2c_imx, IMX_I2C_BIT_RATE);
+       bitrate = IMX_I2C_BIT_RATE;
+       ret = of_property_read_u32(pdev->dev.of_node,
+                                  "clock-frequency", &bitrate);
+       if (ret < 0 && pdata && pdata->bitrate)
+               bitrate = pdata->bitrate;
+       i2c_imx_set_clk(i2c_imx, bitrate);
 
        /* Set up chip registers to defaults */
        writeb(0, i2c_imx->base + IMX_I2C_I2CR);
@@ -554,6 +565,8 @@ static int __init i2c_imx_probe(struct platform_device *pdev)
                goto fail5;
        }
 
+       of_i2c_register_devices(&i2c_imx->adapter);
+
        /* Set up platform driver data */
        platform_set_drvdata(pdev, i2c_imx);
 
@@ -584,7 +597,6 @@ fail1:
 static int __exit i2c_imx_remove(struct platform_device *pdev)
 {
        struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
-       struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
 
        /* remove adapter */
        dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
@@ -613,6 +625,7 @@ static struct platform_driver i2c_imx_driver = {
        .driver = {
                .name   = DRIVER_NAME,
                .owner  = THIS_MODULE,
+               .of_match_table = i2c_imx_dt_ids,
        }
 };