diff options
author | Grant Likely <grant.likely@secretlab.ca> | 2008-01-25 06:25:31 +0100 |
---|---|---|
committer | Grant Likely <grant.likely@secretlab.ca> | 2008-01-26 23:32:19 +0100 |
commit | 4fb4c5582475452d3bf7c5072ef2d15ee06f7723 (patch) | |
tree | 9e75d2795deafb6601fb31c858874ebd554a4135 /drivers/spi | |
parent | [POWERPC] Add common clock setting routine mpc52xx_psc_set_clkdiv() (diff) | |
download | linux-4fb4c5582475452d3bf7c5072ef2d15ee06f7723.tar.xz linux-4fb4c5582475452d3bf7c5072ef2d15ee06f7723.zip |
[POWERPC] mpc52xx_psc_spi device driver must not touch port_config and cdm
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 <grant.likely@secretlab.ca>
Acked-by: Dragos Carp <dragos.carp@toptica.com>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | 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 a3ebc632a477..253ed5682a6d 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; } |