ARM: prima2: move to generic reset controller driver framework

this moves to generic IP module reset framework, and make other drivers
use common device_reset() API.

Cc: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Bin Shi <Bin.Shi@csr.com>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>

arch/arm/mach-prima2/Kconfig

@@ -1,5 +1,6 @@
 config ARCH_SIRF
 	bool "CSR SiRF" if ARCH_MULTI_V7
+	select ARCH_HAS_RESET_CONTROLLER
 	select ARCH_REQUIRE_GPIOLIB
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_IRQ_CHIP

arch/arm/mach-prima2/rstc.c

@@ -13,57 +13,36 @@
 #include <linux/device.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
+#include <linux/platform_device.h>
 #include <linux/reboot.h>
+#include <linux/reset-controller.h>
+
+#define SIRFSOC_RSTBIT_NUM	64
 
 void __iomem *sirfsoc_rstc_base;
 static DEFINE_MUTEX(rstc_lock);
 
-static struct of_device_id rstc_ids[]  = {
-	{ .compatible = "sirf,prima2-rstc" },
-	{ .compatible = "sirf,marco-rstc" },
-	{},
-};
-
-static int __init sirfsoc_of_rstc_init(void)
+static int sirfsoc_reset_module(struct reset_controller_dev *rcdev,
+					unsigned long sw_reset_idx)
 {
-	struct device_node *np;
+	u32 reset_bit = sw_reset_idx;
 
-	np = of_find_matching_node(NULL, rstc_ids);
-	if (!np) {
-		pr_err("unable to find compatible sirf rstc node in dtb\n");
-		return -ENOENT;
-	}
-
-	sirfsoc_rstc_base = of_iomap(np, 0);
-	if (!sirfsoc_rstc_base)
-		panic("unable to map rstc cpu registers\n");
-
-	of_node_put(np);
-
-	return 0;
-}
-early_initcall(sirfsoc_of_rstc_init);
-
-int sirfsoc_reset_device(struct device *dev)
-{
-	u32 reset_bit;
-
-	if (of_property_read_u32(dev->of_node, "reset-bit", &reset_bit))
+	if (reset_bit >= SIRFSOC_RSTBIT_NUM)
 		return -EINVAL;
 
 	mutex_lock(&rstc_lock);
 
-	if (of_device_is_compatible(dev->of_node, "sirf,prima2-rstc")) {
+	if (of_device_is_compatible(rcdev->of_node, "sirf,prima2-rstc")) {
 		/*
 		 * Writing 1 to this bit resets corresponding block. Writing 0 to this
 		 * bit de-asserts reset signal of the corresponding block.
 		 * datasheet doesn't require explicit delay between the set and clear
 		 * of reset bit. it could be shorter if tests pass.
 		 */
-		writel(readl(sirfsoc_rstc_base + (reset_bit / 32) * 4) | reset_bit,
+		writel(readl(sirfsoc_rstc_base + (reset_bit / 32) * 4) | (1 << reset_bit),
 			sirfsoc_rstc_base + (reset_bit / 32) * 4);
 		msleep(10);
-		writel(readl(sirfsoc_rstc_base + (reset_bit / 32) * 4) & ~reset_bit,
+		writel(readl(sirfsoc_rstc_base + (reset_bit / 32) * 4) & ~(1 << reset_bit),
 			sirfsoc_rstc_base + (reset_bit / 32) * 4);
 	} else {
 		/*
@@ -73,9 +52,9 @@ int sirfsoc_reset_device(struct device *dev)
 		 * datasheet doesn't require explicit delay between the set and clear
 		 * of reset bit. it could be shorter if tests pass.
 		 */
-		writel(reset_bit, sirfsoc_rstc_base + (reset_bit / 32) * 8);
+		writel(1 << reset_bit, sirfsoc_rstc_base + (reset_bit / 32) * 8);
 		msleep(10);
-		writel(reset_bit, sirfsoc_rstc_base + (reset_bit / 32) * 8 + 4);
+		writel(1 << reset_bit, sirfsoc_rstc_base + (reset_bit / 32) * 8 + 4);
 	}
 
 	mutex_unlock(&rstc_lock);
@@ -83,6 +62,52 @@ int sirfsoc_reset_device(struct device *dev)
 	return 0;
 }
 
+static struct reset_control_ops sirfsoc_rstc_ops = {
+	.reset = sirfsoc_reset_module,
+};
+
+static struct reset_controller_dev sirfsoc_reset_controller = {
+	.ops = &sirfsoc_rstc_ops,
+	.nr_resets = SIRFSOC_RSTBIT_NUM,
+};
+
+static int sirfsoc_rstc_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	sirfsoc_rstc_base = of_iomap(np, 0);
+	if (!sirfsoc_rstc_base) {
+		dev_err(&pdev->dev, "unable to map rstc cpu registers\n");
+		return -ENOMEM;
+	}
+
+	sirfsoc_reset_controller.of_node = np;
+
+	reset_controller_register(&sirfsoc_reset_controller);
+
+	return 0;
+}
+
+static const struct of_device_id rstc_ids[]  = {
+	{ .compatible = "sirf,prima2-rstc" },
+	{ .compatible = "sirf,marco-rstc" },
+	{},
+};
+
+static struct platform_driver sirfsoc_rstc_driver = {
+	.probe		= sirfsoc_rstc_probe,
+	.driver		= {
+		.name	= "sirfsoc_rstc",
+		.owner	= THIS_MODULE,
+		.of_match_table = rstc_ids,
+	},
+};
+
+static int __init sirfsoc_rstc_init(void)
+{
+	return platform_driver_register(&sirfsoc_rstc_driver);
+}
+subsys_initcall(sirfsoc_rstc_init);
+
 #define SIRFSOC_SYS_RST_BIT  BIT(31)
 
 void sirfsoc_restart(enum reboot_mode mode, const char *cmd)