Re: [PATCH RFC v2] media: tvp514x: add OF support

[Sylwester Nawrocki <sylvester.nawrocki@gmail.com>]

Hi Prabhakar,

On 01/29/2013 02:07 PM, Prabhakar Lad wrote:
[...]
> diff --git a/Documentation/devicetree/bindings/media/i2c/tvp514x.txt b/Documentation/devicetree/bindings/media/i2c/tvp514x.txt
> new file mode 100644
> index 0000000..55d3ffd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/media/i2c/tvp514x.txt
> @@ -0,0 +1,38 @@
> +* Texas Instruments TVP514x video decoder
> +
> +The TVP5146/TVP5146m2/TVP5147/TVP5147m1 device is high quality, single-chip
> +digital video decoder that digitizes and decodes all popular baseband analog
> +video formats into digital video component. The tvp514x decoder supports analog-
> +to-digital (A/D) conversion of component RGB and YPbPr signals as well as A/D
> +conversion and decoding of NTSC, PAL and SECAM composite and S-video into
> +component YCbCr.
> +
> +Required Properties :
> +- compatible: Must be "ti,tvp514x-decoder"

There are no significant differences among TVP514* devices as listed above,
you would like to handle above ?

I'm just wondering if you don't need ,for instance, two separate compatible
properties, e.g. "ti,tvp5146-decoder" and "ti,tvp5147-decoder" ?

> +- hsync-active: HSYNC Polarity configuration for current interface.
> +- vsync-active: VSYNC Polarity configuration for current interface.
> +- data-active: Clock polarity of the current interface.

I guess you mean "pclk-sample: Clock polarity..." ?

> +
> +Example:
> +
> +i2c0@1c22000 {
> +	...
> +	...
> +
> +	tvp514x@5c {
> +		compatible = "ti,tvp514x-decoder";
> +		reg =<0x5c>;
> +
> +		port {
> +			tvp514x_1: endpoint {
> +				/* Active high (Defaults to 0) */
> +				hsync-active =<1>;
> +				/* Active high (Defaults to 0) */
> +				hsync-active =<1>;

Should it be vsync-active ?

> +				/* Active low (Defaults to 0) */
> +				data-active =<0>;

and this pclk-sample ?

> +			};
> +		};
> +	};
> +	...
> +};
> diff --git a/drivers/media/i2c/tvp514x.c b/drivers/media/i2c/tvp514x.c
> index a4f0a70..24ce759 100644
> --- a/drivers/media/i2c/tvp514x.c
> +++ b/drivers/media/i2c/tvp514x.c
> @@ -12,6 +12,7 @@
>    *     Hardik Shah<hardik.shah@ti.com>
>    *     Manjunath Hadli<mrh@ti.com>
>    *     Karicheri Muralidharan<m-karicheri2@ti.com>
> + *     Prabhakar Lad<prabhakar.lad@ti.com>
>    *
>    * This package is free software; you can redistribute it and/or modify
>    * it under the terms of the GNU General Public License version 2 as
> @@ -33,7 +34,9 @@
>   #include<linux/delay.h>
>   #include<linux/videodev2.h>
>   #include<linux/module.h>
> +#include<linux/of_device.h>
>
> +#include<media/v4l2-of.h>
>   #include<media/v4l2-async.h>
>   #include<media/v4l2-device.h>
>   #include<media/v4l2-common.h>
> @@ -930,6 +933,58 @@ static struct tvp514x_decoder tvp514x_dev = {
>
>   };
>
> +#if defined(CONFIG_OF)
> +static const struct of_device_id tvp514x_of_match[] = {
> +	{.compatible = "ti,tvp514x-decoder", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, tvp514x_of_match);
> +
> +static struct tvp514x_platform_data
> +	*tvp514x_get_pdata(struct i2c_client *client)
> +{
> +	if (!client->dev.platform_data&&  client->dev.of_node) {
> +		struct tvp514x_platform_data *pdata;
> +		struct v4l2_of_endpoint bus_cfg;
> +		struct device_node *endpoint;
> +
> +		pdata = devm_kzalloc(&client->dev,
> +				sizeof(struct tvp514x_platform_data),
> +				GFP_KERNEL);
> +		client->dev.platform_data = pdata;

Do you really need to set client->dev.platform_data this way ?
What about passing struct tvp514x_decoder pointer to this function
and initializing struct tvp514x_decoder::pdata instead ?

> +		if (!pdata)
> +			return NULL;
> +
> +		endpoint = of_get_child_by_name(client->dev.of_node, "port");
> +		if (endpoint)
> +			endpoint = of_get_child_by_name(endpoint, "endpoint");

I think you could replace these two calls above with

		endpoint = v4l2_of_get_next_endpoint(client->dev.of_node);

Now I see I should have modified this function to ensure it works also when
'port' nodes are grouped in a 'ports' node.

> +		if (!endpoint) {
> +			v4l2_info(client, "Using default data!!\n");
> +		} else {	
> +			v4l2_of_parse_parallel_bus(endpoint,&bus_cfg);
> +
> +			if (bus_cfg.mbus_flags&  V4L2_MBUS_HSYNC_ACTIVE_HIGH)
> +				pdata->hs_polarity = 1;
> +			if (bus_cfg.mbus_flags&  V4L2_MBUS_VSYNC_ACTIVE_HIGH)
> +				pdata->vs_polarity = 1;
> +			if (bus_cfg.mbus_flags&  V4L2_MBUS_PCLK_SAMPLE_RISING)
> +				pdata->clk_polarity = 1;
> +		}
> +	}
> +
> +	return client->dev.platform_data;
> +}
> +#else
> +#define tvp514x_of_match NULL
> +
> +static struct tvp514x_platform_data
> +	*tvp514x_get_pdata(struct i2c_client *client)
> +{
> +	return client->dev.platform_data;
> +}
> +#endif
> +
>   /**
>    * tvp514x_probe() - decoder driver i2c probe handler
>    * @client: i2c driver client device structure
> @@ -941,6 +996,7 @@ static struct tvp514x_decoder tvp514x_dev = {
>   static int
>   tvp514x_probe(struct i2c_client *client, const struct i2c_device_id *id)
>   {
> +	struct tvp514x_platform_data *pdata;
>   	struct tvp514x_decoder *decoder;
>   	struct v4l2_subdev *sd;
>   	int ret;
> @@ -949,22 +1005,25 @@ tvp514x_probe(struct i2c_client *client, const struct i2c_device_id *id)
>   	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
>   		return -EIO;
>
> +	pdata = tvp514x_get_pdata(client);
> +	if (!pdata) {
> +		v4l2_err(client, "No platform data!!\n");
> +		return -EPROBE_DEFER;
> +	}
> +
>   	decoder = devm_kzalloc(&client->dev, sizeof(*decoder), GFP_KERNEL);
>   	if (!decoder)
>   		return -ENOMEM;
>
>   	/* Initialize the tvp514x_decoder with default configuration */
>   	*decoder = tvp514x_dev;
> -	if (!client->dev.platform_data) {
> -		v4l2_err(client, "No platform data!!\n");
> -		return -EPROBE_DEFER;
> -	}
> +
>   	/* Copy default register configuration */
>   	memcpy(decoder->tvp514x_regs, tvp514x_reg_list_default,
>   			sizeof(tvp514x_reg_list_default));
>
>   	/* Copy board specific information here */
> -	decoder->pdata = client->dev.platform_data;
> +	decoder->pdata = pdata;
>
>   	/**
>   	 * Fetch platform specific data, and configure the
> @@ -1096,6 +1155,7 @@ MODULE_DEVICE_TABLE(i2c, tvp514x_id);
>
>   static struct i2c_driver tvp514x_driver = {
>   	.driver = {
> +		.of_match_table = tvp514x_of_match,
>   		.owner = THIS_MODULE,
>   		.name = TVP514X_MODULE_NAME,
>   	},

--

Regards,
Sylwester