Re: [PATCH 1/5] i2c: Convert i2c-octeon.c to use device tree.

[Rob Herring <robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

On 03/26/2012 07:27 PM, David Daney wrote:
> From: David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
> 
> There are three parts to this:
> 
> 1) Remove the definitions of OCTEON_IRQ_TWSI and OCTEON_IRQ_TWSI2.
>    The interrupts are specified by the device tree and these hard
>    coded irq numbers block the used of the irq lines by the irq_domain
>    code.
> 
> 2) Remove platform device setup code from octeon-platform.c, it is
>    now unused.
> 
> 3) Convert i2c-octeon.c to use device tree.  Part of this includes
>    using the devm_* functions instead of the raw counterparts, thus
>    simplifying error handling.  No functionality is changed.

Shouldn't this patch go after converting the platform to DT?

> Signed-off-by: David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
> Cc: "Jean Delvare (PC drivers, core)" <khali-PUYAD+kWke1g9hUCZPvPmw@public.gmane.org>
> Cc: "Ben Dooks (embedded platforms)" <ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org>
> Cc: "Wolfram Sang (embedded platforms)" <w.sang-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
> Cc: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> ---
> 
> Should probably go via Ralf's linux-mips.org tree.
> 
>  arch/mips/cavium-octeon/octeon-irq.c      |    2 -
>  arch/mips/cavium-octeon/octeon-platform.c |   84 -------------------------
>  arch/mips/include/asm/octeon/octeon.h     |    5 --
>  drivers/i2c/busses/i2c-octeon.c           |   94 ++++++++++++++++-------------
>  4 files changed, 52 insertions(+), 133 deletions(-)

snip

>  
> -	if (i2c_data == NULL) {
> -		dev_err(i2c->dev, "no I2C frequency data\n");
> +	/*
> +	 * "clock-rate" is a legacy binding, the official binding is
> +	 * "clock-frequency".  Try the official one first and then
> +	 * fall back if it doesn't exist.
> +	 */
> +	data = of_get_property(pdev->dev.of_node, "clock-frequency", &len);
> +	if (!data || len != sizeof(*data))
> +		data = of_get_property(pdev->dev.of_node, "clock-rate", &len);
> +	if (data && len == sizeof(*data)) {
> +		i2c->twsi_freq = be32_to_cpup(data);

Can't you use of_property_read_u32?

Does the legacy binding really exist as DT support is new?

Otherwise,

Acked-by: Rob Herring <rob.herring-bsGFqQB8/DxBDgjK7y7TUQ@public.gmane.org>

> +	} else {
> +		dev_err(i2c->dev,
> +			"no I2C 'clock-rate' or 'clock-frequency' property\n");
>  		result = -ENXIO;
> -		goto fail_region;
> +		goto out;
>  	}
>  
> -	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)) {
> +	if (!devm_request_mem_region(&pdev->dev, i2c->twsi_phys, i2c->regsize,
> +				      res_mem->name)) {
>  		dev_err(i2c->dev, "request_mem_region failed\n");
> -		goto fail_region;
> +		goto out;
>  	}
> -	i2c->twsi_base = ioremap(i2c->twsi_phys, i2c->regsize);
> +	i2c->twsi_base = devm_ioremap(&pdev->dev, i2c->twsi_phys, i2c->regsize);
>  
>  	init_waitqueue_head(&i2c->queue);
>  
>  	i2c->irq = irq;
>  
> -	result = request_irq(i2c->irq, octeon_i2c_isr, 0, DRV_NAME, i2c);
> +	result = devm_request_irq(&pdev->dev, i2c->irq,
> +				  octeon_i2c_isr, 0, DRV_NAME, i2c);
>  	if (result < 0) {
>  		dev_err(i2c->dev, "failed to attach interrupt\n");
> -		goto fail_irq;
> +		goto out;
>  	}
>  
>  	result = octeon_i2c_initlowlevel(i2c);
>  	if (result) {
>  		dev_err(i2c->dev, "init low level failed\n");
> -		goto  fail_add;
> +		goto  out;
>  	}
>  
>  	result = octeon_i2c_setclock(i2c);
>  	if (result) {
>  		dev_err(i2c->dev, "clock init failed\n");
> -		goto  fail_add;
> +		goto  out;
>  	}
>  
>  	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;
>  };
> @@ -613,19 +619,24 @@ static int __devexit octeon_i2c_remove(struct platform_device *pdev)
>  
>  	i2c_del_adapter(&i2c->adap);
>  	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 of_device_id octeon_i2c_match[] = {
> +	{
> +		.compatible = "cavium,octeon-3860-twsi",
> +	},
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, octeon_i2c_match);
> +
>  static struct platform_driver octeon_i2c_driver = {
>  	.probe		= octeon_i2c_probe,
>  	.remove		= __devexit_p(octeon_i2c_remove),
>  	.driver		= {
>  		.owner	= THIS_MODULE,
>  		.name	= DRV_NAME,
> +		.of_match_table = octeon_i2c_match,
>  	},
>  };
>  
> @@ -635,4 +646,3 @@ MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext-OYasijW0DpE@public.gmane.org>");
>  MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
>  MODULE_LICENSE("GPL");
>  MODULE_VERSION(DRV_VERSION);
> -MODULE_ALIAS("platform:" DRV_NAME);