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

Sebastian Andrzej Siewior bigeasy at linutronix.de
Thu Dec 2 15:09:46 EST 2010


The Sodaville I2C controller is almost the same as found on PXA2xx. The
difference:
- the register are at a different spot
- 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 at linutronix.de>
Signed-off-by: Dirk Brandewie <dirk.brandewie at gmail.com>
---
 drivers/i2c/busses/Kconfig       |    7 +-
 drivers/i2c/busses/Makefile      |    1 +
 drivers/i2c/busses/i2c-pxa-pci.c |  177 ++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/i2c-pxa.c     |   23 +++++
 4 files changed, 206 insertions(+), 2 deletions(-)
 create mode 100644 drivers/i2c/busses/i2c-pxa-pci.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 3a6321c..9ee3e60 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 84cb16a..78db2e3 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..f7b74b9
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pxa-pci.c
@@ -0,0 +1,177 @@
+/*
+ * 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>
+
+/*
+ * the number of bars is hardcoded because pci_select_bars() reports the
+ * wrong thing.
+ */
+#define CE4100_PCI_I2C_DEVS	3
+
+struct ce4100_i2c_device {
+	struct platform_device pdev;
+	struct resource res[2];
+	struct i2c_pxa_platform_data pdata;
+};
+
+struct ce4100_devices {
+	struct ce4100_i2c_device sd[CE4100_PCI_I2C_DEVS];
+};
+
+static void plat_dev_release(struct device *dev)
+{
+	struct ce4100_i2c_device *sd = container_of(dev,
+			struct ce4100_i2c_device, pdev.dev);
+
+	of_device_node_put(&sd->pdev.dev);
+}
+
+static int add_i2c_device(struct pci_dev *dev, int bar,
+		struct ce4100_i2c_device *sd)
+{
+	struct platform_device *pdev = &sd->pdev;
+	struct i2c_pxa_platform_data *pdata = &sd->pdata;
+	struct device_node *child;
+	int found = 0;
+
+	pdev->name = "pxa2xx-i2c";
+	pdev->dev.release = plat_dev_release;
+	pdev->dev.parent = &dev->dev;
+
+	for_each_child_of_node(dev->dev.of_node, child) {
+		const void *prop;
+		u32 child_reg;
+
+		prop = of_get_property(child, "reg", NULL);
+		if (!prop)
+			continue;
+		child_reg = be32_to_cpup(prop);
+		if (child_reg != bar)
+			continue;
+
+		pdev->dev.of_node = child;
+
+		prop = of_get_property(child, "fast-mode", NULL);
+		if (prop)
+			pdata->fast_mode = 1;
+
+		prop = of_get_property(child, "id", NULL);
+		if (!prop)
+			return -EINVAL;
+
+		pdev->id = be32_to_cpup(prop);
+		found = 1;
+		break;
+	}
+
+	if (!found) {
+		dev_err(&dev->dev, "Missing DT node for bar %d at %s\n", bar,
+				dev->dev.of_node->full_name);
+		return -EINVAL;
+	}
+
+	pdev->dev.platform_data = pdata;
+	pdev->resource = sd->res;
+
+	sd->res[0].flags = IORESOURCE_MEM;
+	sd->res[0].start = pci_resource_start(dev, bar);
+	sd->res[0].end = pci_resource_end(dev, bar);
+
+	sd->res[1].flags = IORESOURCE_IRQ;
+	sd->res[1].start = dev->irq;
+	sd->res[1].end = dev->irq;
+
+	pdev->num_resources = 2;
+
+	return platform_device_register(pdev);
+}
+
+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;
+
+	pci_set_drvdata(dev, sds);
+
+	for (i = 0; i < ARRAY_SIZE(sds->sd); i++) {
+		ret = add_i2c_device(dev, i, &sds->sd[i]);
+		if (ret) {
+			while (--i >= 0)
+				platform_device_unregister(&sds->sd[i].pdev);
+			goto err_dev_add;
+		}
+	}
+	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->sd); i++)
+		platform_device_unregister(&sds->sd[i].pdev);
+
+	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 at linutronix.de>");
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 667f6d9..32982fb 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -88,6 +88,8 @@ MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
 /*
  * I2C registers definitions
  */
+#ifndef CONFIG_X86
+
 #define IBMR		(0x00)
 #define IDBR		(0x04)
 #define ICR		(0x08)
@@ -100,6 +102,27 @@ MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
 #define _ISR(i2c)	((i2c)->reg_base + (ISR << (i2c)->reg_shift))
 #define _ISAR(i2c)	((i2c)->reg_base + (ISAR << (i2c)->reg_shift))
 
+#else
+
+#define IBMR            (0x14)
+#define IDBR            (0x0c)
+#define ICR             (0x00)
+#define ISR             (0x04)
+
+#define _IBMR(i2c)	((i2c)->reg_base + IBMR)
+#define _IDBR(i2c)	((i2c)->reg_base + IDBR)
+#define _ICR(i2c)	((i2c)->reg_base + ICR)
+#define _ISR(i2c)	((i2c)->reg_base + ISR)
+
+struct clk;
+
+#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_i2c {
 	spinlock_t		lock;
 	wait_queue_head_t	wait;
-- 
1.7.3.2




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