Acked-by: Dragos Carp <[EMAIL PROTECTED]>
On Mon, 2008-01-07 at 12:07 -0700, Grant Likely wrote:
> From: Grant Likely <[EMAIL PROTECTED]>
>
> It is dangerous for an mpc52xx device driver to modify the port_config
> register. If the driver is probed incorrectly, it will change the pin
> IO configuration in ways which may not be compatible with the board.
> port_config should be set up by the bootloader, or failing that, in
> the platform setup code in arch/powerpc/platforms/52xx.
>
> Also, modifying CDM registers directly can cause a race condition with
> other drivers. Instead call a common routine to modify CDM settings.
>
> Signed-off-by: Grant Likely <[EMAIL PROTECTED]>
> ---
>
> drivers/spi/mpc52xx_psc_spi.c | 77
> +----------------------------------------
> 1 files changed, 2 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/spi/mpc52xx_psc_spi.c b/drivers/spi/mpc52xx_psc_spi.c
> index a3ebc63..253ed56 100644
> --- a/drivers/spi/mpc52xx_psc_spi.c
> +++ b/drivers/spi/mpc52xx_psc_spi.c
> @@ -330,80 +330,13 @@ static void mpc52xx_psc_spi_cleanup(struct spi_device
> *spi)
>
> static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi
> *mps)
> {
> - struct device_node *np;
> - struct mpc52xx_cdm __iomem *cdm;
> - struct mpc52xx_gpio __iomem *gpio;
> struct mpc52xx_psc __iomem *psc = mps->psc;
> - u32 ul;
> u32 mclken_div;
> int ret = 0;
>
> -#if defined(CONFIG_PPC_MERGE)
> - np = of_find_compatible_node(NULL, NULL, "mpc5200-cdm");
> - cdm = of_iomap(np, 0);
> - of_node_put(np);
> - np = of_find_compatible_node(NULL, NULL, "mpc5200-gpio");
> - gpio = of_iomap(np, 0);
> - of_node_put(np);
> -#else
> - cdm = ioremap(MPC52xx_PA(MPC52xx_CDM_OFFSET), MPC52xx_CDM_SIZE);
> - gpio = ioremap(MPC52xx_PA(MPC52xx_GPIO_OFFSET), MPC52xx_GPIO_SIZE);
> -#endif
> - if (!cdm || !gpio) {
> - printk(KERN_ERR "Error mapping CDM/GPIO\n");
> - ret = -EFAULT;
> - goto unmap_regs;
> - }
> -
> /* default sysclk is 512MHz */
> - mclken_div = 0x8000 |
> - (((mps->sysclk ? mps->sysclk : 512000000) / MCLK) & 0x1FF);
> -
> - switch (psc_id) {
> - case 1:
> - ul = in_be32(&gpio->port_config);
> - ul &= 0xFFFFFFF8;
> - ul |= 0x00000006;
> - out_be32(&gpio->port_config, ul);
> - out_be16(&cdm->mclken_div_psc1, mclken_div);
> - ul = in_be32(&cdm->clk_enables);
> - ul |= 0x00000020;
> - out_be32(&cdm->clk_enables, ul);
> - break;
> - case 2:
> - ul = in_be32(&gpio->port_config);
> - ul &= 0xFFFFFF8F;
> - ul |= 0x00000060;
> - out_be32(&gpio->port_config, ul);
> - out_be16(&cdm->mclken_div_psc2, mclken_div);
> - ul = in_be32(&cdm->clk_enables);
> - ul |= 0x00000040;
> - out_be32(&cdm->clk_enables, ul);
> - break;
> - case 3:
> - ul = in_be32(&gpio->port_config);
> - ul &= 0xFFFFF0FF;
> - ul |= 0x00000600;
> - out_be32(&gpio->port_config, ul);
> - out_be16(&cdm->mclken_div_psc3, mclken_div);
> - ul = in_be32(&cdm->clk_enables);
> - ul |= 0x00000080;
> - out_be32(&cdm->clk_enables, ul);
> - break;
> - case 6:
> - ul = in_be32(&gpio->port_config);
> - ul &= 0xFF8FFFFF;
> - ul |= 0x00700000;
> - out_be32(&gpio->port_config, ul);
> - out_be16(&cdm->mclken_div_psc6, mclken_div);
> - ul = in_be32(&cdm->clk_enables);
> - ul |= 0x00000010;
> - out_be32(&cdm->clk_enables, ul);
> - break;
> - default:
> - ret = -EINVAL;
> - goto unmap_regs;
> - }
> + mclken_div = (mps->sysclk ? mps->sysclk : 512000000) / MCLK;
> + mpc52xx_set_psc_clkdiv(psc_id, mclken_div);
>
> /* Reset the PSC into a known state */
> out_8(&psc->command, MPC52xx_PSC_RST_RX);
> @@ -427,12 +360,6 @@ static int mpc52xx_psc_spi_port_config(int psc_id,
> struct mpc52xx_psc_spi *mps)
>
> mps->bits_per_word = 8;
>
> -unmap_regs:
> - if (cdm)
> - iounmap(cdm);
> - if (gpio)
> - iounmap(gpio);
> -
> return ret;
> }
>
>
>
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