[v4 3/3] sata: imx: add ahci sata support on imx platforms

[s.hauer@pengutronix.de (Sascha Hauer)]

On Wed, Jul 10, 2013 at 04:35:55PM +0800, Richard Zhu wrote:
> From: Richard Zhu <r65037@freescale.com>
> 
> imx6q contains one Synopsys AHCI SATA controller,
> But it can't shares ahci_platform driver with other
> controllers.
> Because there are some misalignments of the generic
> AHCI controller.
> The bits definitions of the HBA registers, the Vendor
> Specific registers, and the AHCI PHY clock.
>  - CAP_SSS(bit20) of the HOST_CAP is writable, default
>  value is '0', should be configured to be '1'
>  - bit0 (only one AHCI SATA port on imx6q) of the
>  HOST_PORTS_IMPL should be set to be '1'.(default 0)
>  - One Vendor Specific register HOST_TIMER1MS(offset:0xe0)
>  should be configured regarding to the frequency of AHB
>  bus clock.
>  - Configurations of the AHCI PHY clock, and the signal
>  parameters of the GPR13
> 
> Setup its own ahci sata driver, contained the imx6q specific
> initialized codes, and re-use the generic ahci_platform drier,
> 
> Signed-off-by: Richard Zhu <r65037@freescale.com>
> ---
>  drivers/ata/Kconfig    |    9 ++
>  drivers/ata/Makefile   |    1 +
>  drivers/ata/sata_imx.c |  237 ++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 247 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/ata/sata_imx.c
> 

[...]

> +
> +/* imx6q ahci module initialization. */
> +static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
> +{
> +	int ret = 0;
> +	unsigned int rc;
> +	struct regmap *gpr;
> +	struct clk *ahb_clk;
> +	struct imx_ahci_priv *imxpriv = (struct imx_ahci_priv *)dev->p;

Just because a pointer points to valid memory doesn't mean that it's
free to use for your purposes. If you look closer maybe you realize that
the imxpriv pointer you use here is another one than the one you
allocate below in your probe function.

I give up here. Maybe I'll write a driver for this when I find time for
it.

Sascha

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