[i2c] [patch 2.6.21-rc3-git +i2c] switch at91 to new-style i2c drivers

[Jean Delvare]

Hi David,

On Thu, 8 Mar 2007 21:36:12 -0800, David Brownell wrote:
> Update AT91 platform support to support "new style" I2C drivers.
> 
>  - Board-specific init functions take i2c_board_info describing ach
>    I2C device on that board, and register that after configuring the
>    adapter and its platform_device.
> 
>  - Make i2c-at91 register as i2c adapter zero (none of these chips
>    seem to have more than one TWI controllers) to make it kick in
>    any board-specific device declarations..
> 
>  - Update all the board specific init code to use that new signature,
>    adding chip declarations (often from schematics) for:
> 
>      * csb337 (ds1307 rtc)
>      * eb9200 (at24c512 eeprom)
>      * rm9200-dk (at24c1024 eeprom, ics1523 clock chip, x9429 pot)
>      * rm9200-ek (ics1523 clock chip, dac3550a audio controller)
> 
>    The ds1307 rtc driver is updated to "new style" in the next patch;
>    there's a new-style at24c eeprom driver I'll post sometime too.
>    So far as I know, the other chips have no Linux-I2C drivers, so
>    those declarations couldn't break old-style drivers.
> 
> Signed-off-by: David Brownell <dbrownell at users.sourceforge.net>
> ---
> NOTE that this doesn't affect the ability to use legacy drivers at
> all ... except for the specific updates listed above.  So the ds1307
> updates will matter, but no other in-tree drivers will care.
> 
>  arch/arm/mach-at91/at91rm9200_devices.c  |    3 ++-
>  arch/arm/mach-at91/at91sam9260_devices.c |    3 ++-
>  arch/arm/mach-at91/at91sam9261_devices.c |    3 ++-
>  arch/arm/mach-at91/board-carmeva.c       |    2 +-
>  arch/arm/mach-at91/board-csb337.c        |    7 ++++++-
>  arch/arm/mach-at91/board-csb637.c        |    2 +-
>  arch/arm/mach-at91/board-dk.c            |   10 +++++++++-
>  arch/arm/mach-at91/board-eb9200.c        |    6 +++++-
>  arch/arm/mach-at91/board-ek.c            |    8 +++++++-
>  arch/arm/mach-at91/board-kafa.c          |    2 +-
>  arch/arm/mach-at91/board-kb9202.c        |    3 ++-
>  arch/arm/mach-at91/board-sam9261ek.c     |    2 +-
>  drivers/i2c/busses/i2c-at91.c            |    6 +++++-
>  include/asm-arm/arch-at91/board.h        |    3 ++-
>  14 files changed, 46 insertions(+), 14 deletions(-)
> 
> 
> Index: at91/drivers/i2c/busses/i2c-at91.c
> ===================================================================
> --- at91.orig/drivers/i2c/busses/i2c-at91.c	2007-03-06 12:19:29.000000000 -0800
> +++ at91/drivers/i2c/busses/i2c-at91.c	2007-03-08 09:18:09.000000000 -0800
> @@ -230,13 +230,14 @@ static int __devinit at91_i2c_probe(stru
>  	adapter->algo = &at91_algorithm;
>  	adapter->class = I2C_CLASS_HWMON;
>  	adapter->dev.parent = &pdev->dev;
> +	/* adapter->id == 0 ... only one TWI controller for now */
>  
>  	platform_set_drvdata(pdev, adapter);
>  
>  	clk_enable(twi_clk);		/* enable peripheral clock */
>  	at91_twi_hwinit();		/* initialize TWI controller */
>  
> -	rc = i2c_add_adapter(adapter);
> +	rc = i2c_add_numbered_adapter(adapter);
>  	if (rc) {
>  		dev_err(&pdev->dev, "Adapter %s registration failed\n",
>  				adapter->name);
> @@ -299,6 +300,9 @@ static int at91_i2c_resume(struct platfo
>  #define at91_i2c_resume		NULL
>  #endif
>  
> +/* work with "modprobe at91_i2c" from hotplugging or coldplugging */
> +MODULE_ALIAS("at91_i2c");

What is it useful for?

> +
>  static struct platform_driver at91_i2c_driver = {
>  	.probe		= at91_i2c_probe,
>  	.remove		= __devexit_p(at91_i2c_remove),
> (...)
> Index: at91/arch/arm/mach-at91/board-dk.c
> ===================================================================
> --- at91.orig/arch/arm/mach-at91/board-dk.c	2007-03-04 15:40:41.000000000 -0800
> +++ at91/arch/arm/mach-at91/board-dk.c	2007-03-08 09:21:56.000000000 -0800
> @@ -99,6 +99,14 @@ static struct at91_mmc_data __initdata d
>  	.wire4		= 1,
>  };
>  
> +static struct i2c_board_info __initdata dk_i2c_devices[] = { {
> +	I2C_BOARD_INFO("ics1523", 0x26, ""),

Why not simply NULL?

> +}, {
> +	I2C_BOARD_INFO("x9429", 0x28, ""),
> +}, {
> +	I2C_BOARD_INFO("at24c", 0x50, "24c1024"),
> +} };

Also, I guess it's a matter of personal taste, but:

static struct i2c_board_info __initdata dk_i2c_devices[] = {
	{ I2C_BOARD_INFO("ics1523", 0x26, "") },
	{ I2C_BOARD_INFO("x9429", 0x28, "") },
	{ I2C_BOARD_INFO("at24c", 0x50, "24c1024") },
};

looks much better IMVHO.

-- 
Jean Delvare