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

Florian Fainelli ffainelli at freebox.fr
Tue Dec 14 09:35:30 EST 2010


Hello Sebastian,

On Thursday 02 December 2010 21:09:46 Sebastian Andrzej Siewior wrote:
> 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

I am surprised of your comment about pci_select_bars, it works fine here on a 
CE4100 device, beware that it will report a bitmask of valid resources (7).

Changing it later would be quite simple anyway.

> +
> +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;



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