RE: [PATCH 2/3] ep93xx: IDE driver platform support code

[H Hartley Sweeten <hartleys@visionengravers.com>]

On Thursday, March 29, 2012 1:19 AM, Rafal Prylowski wrote:
> Signed-off-by: Rafal Prylowski <prylowski@metasoft.pl>
> Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
> Cc: Ryan Mallon <ryan@bluewatersys.com>
>
> ---
>  arch/arm/mach-ep93xx/core.c                  |   36 +++++++++++++++++
>  arch/arm/mach-ep93xx/include/mach/platform.h |    1
>  arch/arm/mach-ep93xx/soc.h                   |    1
>  3 files changed, 38 insertions(+)
>
> Index: linux-2.6/arch/arm/mach-ep93xx/soc.h
> ===================================================================
> --- linux-2.6.orig/arch/arm/mach-ep93xx/soc.h
> +++ linux-2.6/arch/arm/mach-ep93xx/soc.h
> @@ -69,6 +69,7 @@
>  
>  #define EP93XX_BOOT_ROM_BASE		EP93XX_AHB_IOMEM(0x00090000)
>  
> +#define EP93XX_IDE_PHYS_BASE		EP93XX_AHB_PHYS(0x000a0000)
>  #define EP93XX_IDE_BASE			EP93XX_AHB_IOMEM(0x000a0000)
>  
>  #define EP93XX_VIC1_BASE		EP93XX_AHB_IOMEM(0x000b0000)
> Index: linux-2.6/arch/arm/mach-ep93xx/core.c
> ===================================================================
> --- linux-2.6.orig/arch/arm/mach-ep93xx/core.c
> +++ linux-2.6/arch/arm/mach-ep93xx/core.c
> @@ -868,6 +868,42 @@ static struct platform_device ep93xx_wdt
>  	.resource	= ep93xx_wdt_resources,
>  };
>  
> +/*************************************************************************
> + * EP93xx IDE
> + *************************************************************************/
> +static struct resource ep93xx_ide_resources[] = {
> +	[0] = {
> +		.start	= EP93XX_IDE_PHYS_BASE,
> +		.end	= EP93XX_IDE_PHYS_BASE + 0xffff,
> +		.flags	= IORESOURCE_MEM,
> +	},
> +	[1] = {
> +		.start	= IRQ_EP93XX_EXT3,
> +		.end	= IRQ_EP93XX_EXT3,
> +		.flags	= IORESOURCE_IRQ,
> +	},
> +};

Please use the DEFINE_RES_* macros.
Also, the last register in the IDE interface is at offset 0x34, so something like this:

static struct resource ep93xx_ide_resources[] = {
	DEFINE_RES_MEM(EP93XX_IDE_PHYS_BASE, 0x38),
	DEFINE_RES_IRQ(IRQ_EP93XX_EXT3),
};

> +static struct platform_device ep93xx_ide_device = {
> +	.name		= "ep93xx-ide",
> +	.id		= -1,
> +	.dev		= {
> +		.dma_mask		= &ep93xx_ide_device.dev.coherent_dma_mask,
> +		.coherent_dma_mask	= DMA_BIT_MASK(32),
> +	},
> +	.num_resources	= ARRAY_SIZE(ep93xx_ide_resources),
> +	.resource	= ep93xx_ide_resources,
> +};
> +
> +void __init ep93xx_register_ide(void)
> +{
> +	/* GPIO ports E, G and H used by IDE */
> +	ep93xx_devcfg_clear_bits(EP93XX_SYSCON_DEVCFG_EONIDE |
> +				 EP93XX_SYSCON_DEVCFG_GONIDE |
> +				 EP93XX_SYSCON_DEVCFG_HONIDE);
> +	platform_device_register(&ep93xx_ide_device);
> +}

Please create ep93xx_ide_acquire_gpio and ep93xx_ide_acquire_gpio functions
to set/clear the necessary SYSCON bits during the probe/remove of the ide driver.

This should also address your concern mentioned in PATCH 0/3 about making sure
the pin muxing is correct when the driver is loaded.

The *_acquire_gpio function should also gpio_request  the pins before setting the
SYSCON bits. That way if any of the pins are unavailable the driver will not load. Make
sure to gpio_free the pins in the *_release_gpio function.  Look at how the keypad
is handled for an example.

> +
>  void __init ep93xx_init_devices(void)
>  {
>  	/* Disallow access to MaverickCrunch initially */
> Index: linux-2.6/arch/arm/mach-ep93xx/include/mach/platform.h
> ===================================================================
> --- linux-2.6.orig/arch/arm/mach-ep93xx/include/mach/platform.h
> +++ linux-2.6/arch/arm/mach-ep93xx/include/mach/platform.h
> @@ -48,6 +48,7 @@ void ep93xx_register_i2s(void);
>  int ep93xx_i2s_acquire(void);
>  void ep93xx_i2s_release(void);
>  void ep93xx_register_ac97(void);
> +void ep93xx_register_ide(void);
>  
>  void ep93xx_init_devices(void);
>  extern struct sys_timer ep93xx_timer;

Regards,
Hartley