[PATCH] ARM: add DT support to the S3C SDI driver

[Domenico Andreoli <cavokz-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

From: Domenico Andreoli <cavokz-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

This patch adds DeviceTree support to the S3C SDI driver.

It implements all the configurations of the platform driver except the
set_power() callback and the ocr_avail mask.

Signed-off-by: Domenico Andreoli <cavokz-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

---

ocr_avail is a bit mask that could be easily ported to DT. If there
is not any better (or readable) way to render it in DT, I will
straightforwardly implement it.

set_power() instead deserves some more considerations. Current
implementations boil down to gpio on/off settings, its DT implementation
is again straightforward. Problem would arise if any board requires
some naive implementation, would it require a different of_device_id
with proper .data set?

cheers,
Domenico

---
 drivers/mmc/host/s3cmci.c |   83 +++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 78 insertions(+), 5 deletions(-)

Index: b/drivers/mmc/host/s3cmci.c
===================================================================
--- a/drivers/mmc/host/s3cmci.c
+++ b/drivers/mmc/host/s3cmci.c
@@ -14,6 +14,7 @@
 #include <linux/module.h>
 #include <linux/dma-mapping.h>
 #include <linux/clk.h>
+#include <linux/slab.h>
 #include <linux/mmc/host.h>
 #include <linux/platform_device.h>
 #include <linux/cpufreq.h>
@@ -22,6 +23,8 @@
 #include <linux/gpio.h>
 #include <linux/irq.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
 
 #include <mach/dma.h>
 
@@ -1544,6 +1547,58 @@
 
 #endif /* CONFIG_DEBUG_FS */
 
+#ifdef CONFIG_OF
+
+enum of_s3cmci_flags {
+	OF_S3CMCI_USE_DMA = 1,
+};
+
+static struct s3c24xx_mci_pdata *s3cmci_of_init(struct device *dev)
+{
+	struct s3c24xx_mci_pdata *pdata;
+	const __be32 *spec;
+	enum of_gpio_flags gpio_flags;
+	int gpio;
+	u32 flags;
+
+	pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
+	if(!pdata) {
+		dev_err(dev, "%s: failed to allocate pdata\n", dev->of_node->full_name);
+		return NULL;
+	}
+
+	gpio = of_get_gpio_flags(dev->of_node, 0, &gpio_flags);
+	if (gpio < 0) {
+		pdata->no_detect = 1;
+	} else {
+		pdata->gpio_detect = gpio;
+		pdata->detect_invert = (gpio_flags & OF_GPIO_ACTIVE_LOW) == OF_GPIO_ACTIVE_LOW;
+	}
+
+	gpio = of_get_gpio_flags(dev->of_node, 1, &gpio_flags);
+	if (gpio < 0) {
+		pdata->no_wprotect = 1;
+	} else {
+		pdata->gpio_wprotect = gpio;
+		pdata->wprotect_invert = (gpio_flags & OF_GPIO_ACTIVE_LOW) == OF_GPIO_ACTIVE_LOW;
+	}
+
+	spec = of_get_property(dev->of_node, "flags", 0);
+	flags = spec ? be32_to_cpup(spec) : 0;
+	pdata->use_dma = flags | OF_S3CMCI_USE_DMA;
+
+	return pdata;
+}
+
+#else
+
+static struct s3c24xx_mci_pdata *s3cmci_of_init(struct device *dev)
+{
+	return NULL;
+}
+
+#endif /* CONFIG_OF */
+
 static int __devinit s3cmci_probe(struct platform_device *pdev)
 {
 	struct s3cmci_host *host;
@@ -1552,7 +1607,12 @@
 	int is2440;
 	int i;
 
-	is2440 = platform_get_device_id(pdev)->driver_data;
+	if (platform_get_device_id(pdev))
+		is2440 = platform_get_device_id(pdev)->driver_data;
+	else if (pdev->dev.of_match)
+		is2440 = (int) pdev->dev.of_match->data;
+	else
+		BUG();
 
 	mmc = mmc_alloc_host(sizeof(struct s3cmci_host), &pdev->dev);
 	if (!mmc) {
@@ -1577,11 +1637,11 @@
 	host->pdev	= pdev;
 	host->is2440	= is2440;
 
-	host->pdata = pdev->dev.platform_data;
-	if (!host->pdata) {
+	if (!pdev->dev.platform_data && pdev->dev.of_node)
+		pdev->dev.platform_data = s3cmci_of_init(&pdev->dev);
+	if (!pdev->dev.platform_data)
 		pdev->dev.platform_data = &s3cmci_def_pdata;
-		host->pdata = &s3cmci_def_pdata;
-	}
+	host->pdata = pdev->dev.platform_data;
 
 	spin_lock_init(&host->complete_lock);
 	tasklet_init(&host->pio_tasklet, pio_tasklet, (unsigned long) host);
@@ -1901,12 +1961,25 @@
 #define s3cmci_pm_ops NULL
 #endif /* CONFIG_PM */
 
+#ifdef CONFIG_OF
+
+static const struct of_device_id s3cmci_of_match[] = {
+	{ .compatible = "samsung,s3c2410-sdi", .data = (void *) 0, },
+	{ .compatible = "samsung,s3c2412-sdi", .data = (void *) 1, },
+	{ .compatible = "samsung,s3c2440-sdi", .data = (void *) 1, },
+	{},
+};
+
+#else /* CONFIG_OF */
+#define s3cmci_of_match  NULL
+#endif /* CONFIG_OF */
 
 static struct platform_driver s3cmci_driver = {
 	.driver	= {
 		.name	= "s3c-sdi",
 		.owner	= THIS_MODULE,
 		.pm	= s3cmci_pm_ops,
+		.of_match_table = s3cmci_of_match,
 	},
 	.id_table	= s3cmci_driver_ids,
 	.probe		= s3cmci_probe,