[PATCH v1 2/5] mmc: mxs-mmc: add dt probe support

[Dong Aisheng <b29396@freescale.com>]

From: Dong Aisheng <dong.aisheng@linaro.org>

Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>

---
The patch is still using a private way for dma part binding
since the common dma binding is still under discussion.
http://www.spinics.net/lists/linux-omap/msg65528.html

Will update to use common dma binding when it hits mainline.
---
 .../devicetree/bindings/mmc/fsl-mxs-mmc.txt        |   23 ++++++
 drivers/mmc/host/mxs-mmc.c                         |   82 +++++++++++++++++++-
 2 files changed, 102 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/mmc/fsl-mxs-mmc.txt b/Documentation/devicetree/bindings/mmc/fsl-mxs-mmc.txt
new file mode 100644
index 0000000..adc1142
--- /dev/null
+++ b/Documentation/devicetree/bindings/mmc/fsl-mxs-mmc.txt
@@ -0,0 +1,23 @@
+* FREESCALE MXS MMC peripheral
+
+Required properties:
+- compatible : Should be "fsl,<chip>-mmc"
+- reg : Should contain registers location and length
+- interrupts : Should contain interrupt.
+  The format is <irq_err irq_dma>.
+- dma_channel: Should contain the dma channel it uses
+
+Optional properties:
+- wp-gpios : Specify GPIOs for write protection
+- slot-4bit: Specify 4 bit mode support
+- slot-8bit: Specify 8 bit and 4 bit mode support
+
+Examples:
+mmc1: ssp@80010000 {
+	compatible = "fsl,imx28-mmc";
+	reg = <0x80010000 2000>;
+	/* <irq_err irq_dma> */
+	interrupts = <96 82>;
+	dma_channel = <0>;
+	slot-8bit;
+};
diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
index 382c835..6cf2d17 100644
--- a/drivers/mmc/host/mxs-mmc.c
+++ b/drivers/mmc/host/mxs-mmc.c
@@ -38,6 +38,10 @@
 #include <linux/gpio.h>
 #include <linux/regulator/consumer.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/slab.h>
 
 #include <mach/mxs.h>
 #include <mach/common.h>
@@ -673,17 +677,79 @@ static bool mxs_mmc_dma_filter(struct dma_chan *chan, void *param)
 	return true;
 }
 
+#ifdef CONFIG_OF
+static struct resource * __devinit mxs_mmc_get_of_dmares(
+				struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct resource *dmares;
+	int ret;
+
+	if (!np)
+		return NULL;
+
+	dmares = kzalloc(sizeof(*dmares), GFP_KERNEL);
+	dmares->flags = IORESOURCE_DMA;
+	ret = of_property_read_u32(np, "dma_channel", &dmares->start);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to get dmares from dt\n");
+		return NULL;
+	}
+	dmares->end = dmares->start;
+
+	return dmares;
+}
+
+static int __devinit mxs_mmc_get_of_property(struct platform_device *pdev,
+				struct mxs_mmc_platform_data **ppdata)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mxs_mmc_platform_data *pdata = *ppdata;
+
+	if (!np)
+		return -ENODEV;
+
+	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
+
+	if (of_get_property(np, "slot-8bit", NULL))
+		pdata->flags |= SLOTF_8_BIT_CAPABLE;
+
+	if (of_get_property(np, "slot-4bit", NULL))
+		pdata->flags |= SLOTF_4_BIT_CAPABLE;
+
+	pdata->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
+
+	dev_dbg(&pdev->dev, "wp-gpios %d flags %d\n", pdata->wp_gpio,
+		pdata->flags);
+
+	return 0;
+}
+#else
+static struct resource * __devinit mxs_mmc_get_of_dmares(
+				struct platform_device *pdev)
+{
+	return NULL;
+}
+static inline int mxs_mmc_get_of_property(struct platform_device *pdev,
+			struct mxs_mmc_platform_data *pdata)
+{
+	return -ENODEV;
+}
+#endif
+
 static int mxs_mmc_probe(struct platform_device *pdev)
 {
 	struct mxs_mmc_host *host;
 	struct mmc_host *mmc;
 	struct resource *iores, *dmares, *r;
-	struct mxs_mmc_platform_data *pdata;
+	struct mxs_mmc_platform_data *pdata = NULL;
 	int ret = 0, irq_err, irq_dma;
 	dma_cap_mask_t mask;
 
 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+	dmares = mxs_mmc_get_of_dmares(pdev);
+	if (dmares == NULL)
+		dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
 	irq_err = platform_get_irq(pdev, 0);
 	irq_dma = platform_get_irq(pdev, 1);
 	if (!iores || !dmares || irq_err < 0 || irq_dma < 0)
@@ -740,7 +806,9 @@ static int mxs_mmc_probe(struct platform_device *pdev)
 	mmc->caps = MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
 		    MMC_CAP_SDIO_IRQ | MMC_CAP_NEEDS_POLL;
 
-	pdata =	mmc_dev(host->mmc)->platform_data;
+	mxs_mmc_get_of_property(pdev, &pdata);
+	if (pdata == NULL)
+		pdata =	mmc_dev(host->mmc)->platform_data;
 	if (pdata) {
 		if (pdata->flags & SLOTF_8_BIT_CAPABLE)
 			mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
@@ -851,6 +919,13 @@ static const struct dev_pm_ops mxs_mmc_pm_ops = {
 };
 #endif
 
+static const struct of_device_id mxs_mmc_dt_ids[] = {
+	{ .compatible = "fsl,imx23-mmc", .data = NULL, },
+	{ .compatible = "fsl,imx28-mmc", .data = NULL, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_mmc_dt_ids);
+
 static struct platform_driver mxs_mmc_driver = {
 	.probe		= mxs_mmc_probe,
 	.remove		= mxs_mmc_remove,
@@ -860,6 +935,7 @@ static struct platform_driver mxs_mmc_driver = {
 #ifdef CONFIG_PM
 		.pm	= &mxs_mmc_pm_ops,
 #endif
+		.of_match_table = mxs_mmc_dt_ids,
 	},
 };
 
-- 
1.7.0.4