On Sun, 19 Jun 2016 23:40:35 +0800
Icenowy Zheng <icen...@aosc.xyz> wrote:
> The NAND controller on some sun8i chips needs its reset line to be deasserted
> before they can enter working state. This commit added the reset line process
> to the driver.
>
> Signed-off-by: Icenowy Zheng <icen...@aosc.xyz>
> ---
> Changes in v2:
> - Corrected the error checking code of reset line.
>
> Changes in v3:
> - Corrected a more serious error brought in the "fix" of v2.
>
> Changes in v4:
> - Removed unneeded code block after "else".
>
> drivers/mtd/nand/sunxi_nand.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/drivers/mtd/nand/sunxi_nand.c b/drivers/mtd/nand/sunxi_nand.c
> index a83a690..b37075b 100644
> --- a/drivers/mtd/nand/sunxi_nand.c
> +++ b/drivers/mtd/nand/sunxi_nand.c
> @@ -39,6 +39,7 @@
> #include <linux/gpio.h>
> #include <linux/interrupt.h>
> #include <linux/iopoll.h>
> +#include <linux/reset.h>
>
> #define NFC_REG_CTL 0x0000
> #define NFC_REG_ST 0x0004
> @@ -269,6 +270,7 @@ struct sunxi_nfc {
> void __iomem *regs;
> struct clk *ahb_clk;
> struct clk *mod_clk;
> + struct reset_control *reset;
> unsigned long assigned_cs;
> unsigned long clk_rate;
> struct list_head chips;
> @@ -1871,6 +1873,19 @@ static int sunxi_nfc_probe(struct platform_device
> *pdev)
> if (ret)
> goto out_ahb_clk_unprepare;
>
> + nfc->reset = devm_reset_control_get_optional(dev, "ahb");
> +
> + if (!IS_ERR(nfc->reset)) {
> + ret = reset_control_deassert(nfc->reset);
> + if (ret) {
> + dev_err(dev, "reset err %d\n", ret);
> + goto out_mod_clk_unprepare;
> + }
> + }
> + else if (PTR_ERR(nfc->reset) != -ENOENT) {
} else if (...) {
> + return PTR_ERR(nfc->reset);
> + }
> +
> ret = sunxi_nfc_rst(nfc);
> if (ret)
> goto out_mod_clk_unprepare;
And you should probably reassert the reset line in case of errors and
in the ->remove() hook.
--
You received this message because you are subscribed to the Google Groups
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to linux-sunxi+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
