[RFC PATCH 07/10] i2c: Convert i2c-octeon.c to use device tree.
Grant Likely
grant.likely at secretlab.ca
Thu Feb 24 03:25:38 EST 2011
On Tue, Feb 22, 2011 at 12:57:51PM -0800, David Daney wrote:
> Signed-off-by: David Daney <ddaney at caviumnetworks.com>
> Cc: "Jean Delvare (PC drivers, core)" <khali at linux-fr.org>
> Cc: "Ben Dooks (embedded platforms)" <ben-linux at fluff.org>
> Cc: linux-i2c at vger.kernel.org
> ---
> arch/mips/cavium-octeon/octeon-platform.c | 84 ---------------------------
> arch/mips/include/asm/octeon/octeon.h | 5 --
> drivers/i2c/busses/i2c-octeon.c | 88 +++++++++++++---------------
> 3 files changed, 41 insertions(+), 136 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
> index 56dbe54..99a20c6 100644
> --- a/drivers/i2c/busses/i2c-octeon.c
> +++ b/drivers/i2c/busses/i2c-octeon.c
> @@ -11,17 +11,21 @@
> * warranty of any kind, whether express or implied.
> */
>
> +#include <linux/platform_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_address.h>
> +#include <linux/interrupt.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_i2c.h>
Nit: generally the of_*.h headers are kept together. Also this patch
probably won't need of_address.h or of_irq.h after addressing my
comments below.
> +#include <linux/delay.h>
> #include <linux/sched.h>
> #include <linux/slab.h>
> #include <linux/init.h>
> -
> -#include <linux/io.h>
> #include <linux/i2c.h>
> -#include <linux/interrupt.h>
> -#include <linux/delay.h>
> -#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <linux/of.h>
>
> #include <asm/octeon/octeon.h>
>
> @@ -67,9 +71,7 @@ struct octeon_i2c {
> int irq;
> int twsi_freq;
> int sys_freq;
> - resource_size_t twsi_phys;
> void __iomem *twsi_base;
> - resource_size_t regsize;
> struct device *dev;
> };
>
> @@ -511,17 +513,18 @@ static int __devinit octeon_i2c_initlowlevel(struct octeon_i2c *i2c)
> return -EIO;
> }
>
> -static int __devinit octeon_i2c_probe(struct platform_device *pdev)
> +static int __devinit octeon_i2c_probe(struct platform_device *pdev,
> + const struct of_device_id *match)
> {
> int irq, result = 0;
> struct octeon_i2c *i2c;
> - struct octeon_i2c_data *i2c_data;
> - struct resource *res_mem;
> + const __be32 *data;
> + int len;
>
> /* All adaptors have an irq. */
> - irq = platform_get_irq(pdev, 0);
> - if (irq < 0)
> - return irq;
> + irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
> + if (!irq)
> + return -ENXIO;
Platform_get_irq() works for dt registered devices, this hunk can be
dropped.
>
> i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
> if (!i2c) {
> @@ -530,32 +533,16 @@ static int __devinit octeon_i2c_probe(struct platform_device *pdev)
> goto out;
> }
> i2c->dev = &pdev->dev;
> - i2c_data = pdev->dev.platform_data;
> -
> - res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> -
> - if (res_mem == NULL) {
> - dev_err(i2c->dev, "found no memory resource\n");
> - result = -ENXIO;
> - goto fail_region;
> - }
Ditto for platform_get_resource()
>
> - if (i2c_data == NULL) {
> - dev_err(i2c->dev, "no I2C frequency data\n");
> - result = -ENXIO;
> - goto fail_region;
> - }
> + data = of_get_property(pdev->dev.of_node, "clock-rate", &len);
> + if (data && len == sizeof(*data))
> + i2c->twsi_freq = be32_to_cpup(data);
> + else
> + i2c->twsi_freq = 100000;
Seems to me that if the clock-rate (although it should be called
clock-frequency) property is not present, the driver should complain
loudly and refuse to load. Don't fudge it.
>
> - i2c->twsi_phys = res_mem->start;
> - i2c->regsize = resource_size(res_mem);
> - i2c->twsi_freq = i2c_data->i2c_freq;
> - i2c->sys_freq = i2c_data->sys_freq;
> + i2c->sys_freq = octeon_get_io_clock_rate();
>
> - if (!request_mem_region(i2c->twsi_phys, i2c->regsize, res_mem->name)) {
> - dev_err(i2c->dev, "request_mem_region failed\n");
> - goto fail_region;
> - }
> - i2c->twsi_base = ioremap(i2c->twsi_phys, i2c->regsize);
> + i2c->twsi_base = of_iomap(pdev->dev.of_node, 0);
This hunk can also be dropped.
>
> init_waitqueue_head(&i2c->queue);
>
> @@ -581,27 +568,27 @@ static int __devinit octeon_i2c_probe(struct platform_device *pdev)
>
> i2c->adap = octeon_i2c_ops;
> i2c->adap.dev.parent = &pdev->dev;
> - i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
> + i2c->adap.dev.of_node = pdev->dev.of_node;
> i2c_set_adapdata(&i2c->adap, i2c);
> platform_set_drvdata(pdev, i2c);
>
> - result = i2c_add_numbered_adapter(&i2c->adap);
> + result = i2c_add_adapter(&i2c->adap);
> if (result < 0) {
> dev_err(i2c->dev, "failed to add adapter\n");
> goto fail_add;
> }
> -
> dev_info(i2c->dev, "version %s\n", DRV_VERSION);
>
> - return result;
> + of_i2c_register_devices(&i2c->adap);
> +
> + return 0;
>
> fail_add:
> platform_set_drvdata(pdev, NULL);
> free_irq(i2c->irq, i2c);
> fail_irq:
> iounmap(i2c->twsi_base);
> - release_mem_region(i2c->twsi_phys, i2c->regsize);
> -fail_region:
> +
> kfree(i2c);
> out:
> return result;
> @@ -615,17 +602,25 @@ static int __devexit octeon_i2c_remove(struct platform_device *pdev)
> platform_set_drvdata(pdev, NULL);
> free_irq(i2c->irq, i2c);
> iounmap(i2c->twsi_base);
> - release_mem_region(i2c->twsi_phys, i2c->regsize);
> kfree(i2c);
> return 0;
> };
>
> -static struct platform_driver octeon_i2c_driver = {
> +static struct of_device_id octeon_i2c_match[] = {
> + {
> + .compatible = "octeon,twsi",
Need documentation for this binding added to
Documentation/devicetree/bindings. Compatible values for SoC devices
should generally be in the form "<vendor>,<soc-name>-<device-name>".
> + },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, octeon_i2c_match);
> +
> +static struct of_platform_driver octeon_i2c_driver = {
of_platform_driver is deprecated. As long as the .of_match_table is
populated, a normal platform_driver will just work.
> .probe = octeon_i2c_probe,
> .remove = __devexit_p(octeon_i2c_remove),
> .driver = {
> .owner = THIS_MODULE,
> .name = DRV_NAME,
> + .of_match_table = octeon_i2c_match,
> },
> };
>
> @@ -633,20 +628,19 @@ static int __init octeon_i2c_init(void)
> {
> int rv;
>
> - rv = platform_driver_register(&octeon_i2c_driver);
> + rv = of_register_platform_driver(&octeon_i2c_driver);
Drop this change.
On that note, this routine is typically simplified to:
+ {
+ return platform_driver_register(&octeon_i2c_driver);
+ }
>
> static void __exit octeon_i2c_exit(void)
> {
> - platform_driver_unregister(&octeon_i2c_driver);
> + of_unregister_platform_driver(&octeon_i2c_driver);
Drop this hunk.
> }
>
> MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext at nsn.com>");
> MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
> MODULE_LICENSE("GPL");
> MODULE_VERSION(DRV_VERSION);
> -MODULE_ALIAS("platform:" DRV_NAME);
>
> module_init(octeon_i2c_init);
> module_exit(octeon_i2c_exit);
> --
> 1.7.2.3
>
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