[PATCH 3/6] i2c-pxa2xx: Add PCI support for PXA I2C controller

[bigeasy@linutronix.de (Sebastian Andrzej Siewior)]

The Sodaville I2C controller is almost the same as found on PXA2xx. The
difference:
- the register are at a different offset
- no slave support

The PCI probe code adds three platform devices which are probed then by
the platform code.
The X86 part also adds dummy clock defines because we don't have HW
clock support.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
---
 drivers/i2c/busses/Kconfig       |    7 +-
 drivers/i2c/busses/Makefile      |    1 +
 drivers/i2c/busses/i2c-pxa-pci.c |  176 ++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/i2c-pxa.c     |   27 +++++-
 4 files changed, 206 insertions(+), 5 deletions(-)
 create mode 100644 drivers/i2c/busses/i2c-pxa-pci.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 113505a..deefa13 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -525,15 +525,18 @@ config I2C_PNX
 
 config I2C_PXA
 	tristate "Intel PXA2XX I2C adapter"
-	depends on ARCH_PXA || ARCH_MMP
+	depends on ARCH_PXA || ARCH_MMP || (X86_32 && PCI && OF)
 	help
 	  If you have devices in the PXA I2C bus, say yes to this option.
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-pxa.
 
+config I2C_PXA_PCI
+	def_bool I2C_PXA && X86_32 && PCI && OF
+
 config I2C_PXA_SLAVE
 	bool "Intel PXA2XX I2C Slave comms support"
-	depends on I2C_PXA
+	depends on I2C_PXA && !X86_32
 	help
 	  Support I2C slave mode communications on the PXA I2C bus.  This
 	  is necessary for systems where the PXA may be a target on the
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 9d2d0ec..e95d0bf 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_I2C_PCA_PLATFORM)	+= i2c-pca-platform.o
 obj-$(CONFIG_I2C_PMCMSP)	+= i2c-pmcmsp.o
 obj-$(CONFIG_I2C_PNX)		+= i2c-pnx.o
 obj-$(CONFIG_I2C_PXA)		+= i2c-pxa.o
+obj-$(CONFIG_I2C_PXA_PCI)	+= i2c-pxa-pci.o
 obj-$(CONFIG_I2C_S3C2410)	+= i2c-s3c2410.o
 obj-$(CONFIG_I2C_S6000)		+= i2c-s6000.o
 obj-$(CONFIG_I2C_SH7760)	+= i2c-sh7760.o
diff --git a/drivers/i2c/busses/i2c-pxa-pci.c b/drivers/i2c/busses/i2c-pxa-pci.c
new file mode 100644
index 0000000..6659d26
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pxa-pci.c
@@ -0,0 +1,176 @@
+/*
+ * The CE4100's I2C device is more or less the same one as found on PXA.
+ * It does not support slave mode, the register slightly moved. This PCI
+ * device provides three bars, every contains a single I2C controller.
+ */
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/i2c/pxa-i2c.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+
+#define CE4100_PCI_I2C_DEVS	3
+
+struct ce4100_devices {
+	struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
+};
+
+static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
+{
+	struct platform_device *pdev;
+	struct i2c_pxa_platform_data pdata;
+	struct resource res[2];
+	struct device_node *child;
+	static int devnum;
+	int ret;
+
+	memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data));
+	memset(&res, 0, sizeof(res));
+
+	res[0].flags = IORESOURCE_MEM;
+	res[0].start = pci_resource_start(dev, bar);
+	res[0].end = pci_resource_end(dev, bar);
+
+	res[1].flags = IORESOURCE_IRQ;
+	res[1].start = dev->irq;
+	res[1].end = dev->irq;
+
+	for_each_child_of_node(dev->dev.of_node, child) {
+		const void *prop;
+		struct resource r;
+		int ret;
+
+		ret = of_address_to_resource(child, 0, &r);
+		if (ret < 0)
+			continue;
+		if (r.start != res[0].start)
+			continue;
+		if (r.end != res[0].end)
+			continue;
+		if (r.flags != res[0].flags)
+			continue;
+
+		prop = of_get_property(child, "fast-mode", NULL);
+		if (prop)
+			pdata.fast_mode = 1;
+
+		break;
+	}
+
+	if (!child) {
+		dev_err(&dev->dev, "failed to match a DT node for bar %d.\n",
+				bar);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	pdev = platform_device_alloc("ce4100-i2c", devnum);
+	if (!pdev) {
+		of_node_put(child);
+		ret = -ENOMEM;
+		goto out;
+	}
+	pdev->dev.parent = &dev->dev;
+	pdev->dev.of_node = child;
+
+	ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
+	if (ret)
+		goto err;
+
+	ret = platform_device_add_data(pdev, &pdata, sizeof(pdata));
+	if (ret)
+		goto err;
+
+	ret = platform_device_add(pdev);
+	if (ret)
+		goto err;
+	devnum++;
+	return pdev;
+err:
+	platform_device_put(pdev);
+out:
+	return ERR_PTR(ret);
+}
+
+static int __devinit ce4100_i2c_probe(struct pci_dev *dev,
+		const struct pci_device_id *ent)
+{
+	int ret;
+	int i;
+	struct ce4100_devices *sds;
+
+	ret = pci_enable_device_mem(dev);
+	if (ret)
+		return ret;
+
+	if (!dev->dev.of_node) {
+		dev_err(&dev->dev, "Missing device tree node.\n");
+		return -EINVAL;
+	}
+	sds = kzalloc(sizeof(*sds), GFP_KERNEL);
+	if (!sds)
+		goto err_mem;
+
+	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
+		sds->pdev[i] = add_i2c_device(dev, i);
+		if (IS_ERR(sds->pdev[i])) {
+			while (--i >= 0)
+				platform_device_unregister(sds->pdev[i]);
+			goto err_dev_add;
+		}
+	}
+	pci_set_drvdata(dev, sds);
+	return 0;
+
+err_dev_add:
+	pci_set_drvdata(dev, NULL);
+	kfree(sds);
+err_mem:
+	pci_disable_device(dev);
+	return ret;
+}
+
+static void __devexit ce4100_i2c_remove(struct pci_dev *dev)
+{
+	struct ce4100_devices *sds;
+	unsigned int i;
+
+	sds = pci_get_drvdata(dev);
+	pci_set_drvdata(dev, NULL);
+
+	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++)
+		platform_device_unregister(sds->pdev[i]);
+
+	pci_disable_device(dev);
+	kfree(sds);
+}
+
+static struct pci_device_id ce4100_i2c_devices[] __devinitdata = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
+	{ },
+};
+MODULE_DEVICE_TABLE(pci, ce4100_i2c_devices);
+
+static struct pci_driver ce4100_i2c_driver = {
+	.name           = "ce4100_i2c",
+	.id_table       = ce4100_i2c_devices,
+	.probe          = ce4100_i2c_probe,
+	.remove         = __devexit_p(ce4100_i2c_remove),
+};
+
+static int __init ce4100_i2c_init(void)
+{
+	return pci_register_driver(&ce4100_i2c_driver);
+}
+module_init(ce4100_i2c_init);
+
+static void __exit ce4100_i2c_exit(void)
+{
+	pci_unregister_driver(&ce4100_i2c_driver);
+}
+module_exit(ce4100_i2c_exit);
+
+MODULE_DESCRIPTION("CE4100 PCI-I2C glue code for PXA's driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index fc2a90e..225e9a5 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -38,6 +38,13 @@
 
 #include <asm/irq.h>
 
+#ifdef CONFIG_X86
+#define clk_get(dev, id)	NULL
+#define clk_put(clk)		do { } while (0)
+#define clk_disable(clk)	do { } while (0)
+#define clk_enable(clk)		do { } while (0)
+#endif
+
 struct pxa_reg_layout {
 	u32 ibmr;
 	u32 idbr;
@@ -49,6 +56,7 @@ struct pxa_reg_layout {
 enum pxa_i2c_types {
 	REGS_PXA2XX,
 	REGS_PXA3XX,
+	REGS_CE4100,
 };
 
 /*
@@ -69,11 +77,19 @@ static struct pxa_reg_layout pxa_reg_layout[] = {
 		.isr =	0x18,
 		.isar =	0x20,
 	},
+	[REGS_CE4100] = {
+		.ibmr =	0x14,
+		.idbr =	0x0c,
+		.icr =	0x00,
+		.isr =	0x04,
+		/* no isar register */
+	},
 };
 
 static const struct platform_device_id i2c_pxa_id_table[] = {
 	{ "pxa2xx-i2c",		REGS_PXA2XX },
 	{ "pxa3xx-pwri2c",	REGS_PXA3XX },
+	{ "ce4100-i2c",		REGS_CE4100 },
 	{ },
 };
 MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
@@ -442,7 +458,8 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
 	writel(I2C_ISR_INIT, _ISR(i2c));
 	writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
 
-	writel(i2c->slave_addr, _ISAR(i2c));
+	if (i2c->reg_isar)
+		writel(i2c->slave_addr, _ISAR(i2c));
 
 	/* set control register values */
 	writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
@@ -1074,7 +1091,8 @@ static int i2c_pxa_probe(struct platform_device *dev)
 	i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
 	i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
 	i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
-	i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
+	if (i2c_type != REGS_CE4100)
+		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
 
 	i2c->iobase = res->start;
 	i2c->iosize = resource_size(res);
@@ -1113,7 +1131,10 @@ static int i2c_pxa_probe(struct platform_device *dev)
 	i2c->adap.algo_data = i2c;
 	i2c->adap.dev.parent = &dev->dev;
 
-	ret = i2c_add_numbered_adapter(&i2c->adap);
+	if (i2c_type == REGS_CE4100)
+		ret = i2c_add_adapter(&i2c->adap);
+	else
+		ret = i2c_add_numbered_adapter(&i2c->adap);
 	if (ret < 0) {
 		printk(KERN_INFO "I2C: Failed to add bus\n");
 		goto eadapt;
-- 
1.7.4