On Wed, 19 Oct 2016 17:52:05 -0200
Sergio Prado <sergio.pr...@e-labworks.com> wrote:
> Allows configuring Samsung's s3c2410 memory controller using a
> devicetree.
>
> Signed-off-by: Sergio Prado <sergio.pr...@e-labworks.com>
> ---
> drivers/mtd/nand/s3c2410.c | 155
> ++++++++++++++++++++++---
> include/linux/platform_data/mtd-nand-s3c2410.h | 1 +
> 2 files changed, 140 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
> index 371db0d48135..52f768f01b0d 100644
> --- a/drivers/mtd/nand/s3c2410.c
> +++ b/drivers/mtd/nand/s3c2410.c
> @@ -39,6 +39,8 @@
> #include <linux/slab.h>
> #include <linux/clk.h>
> #include <linux/cpufreq.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
>
> #include <linux/mtd/mtd.h>
> #include <linux/mtd/nand.h>
> @@ -185,6 +187,22 @@ struct s3c2410_nand_info {
> #endif
> };
>
> +struct s3c24XX_nand_devtype_data {
> + enum s3c_cpu_type type;
> +};
> +
> +static const struct s3c24XX_nand_devtype_data s3c2410_nand_devtype_data = {
> + .type = TYPE_S3C2410,
> +};
> +
> +static const struct s3c24XX_nand_devtype_data s3c2412_nand_devtype_data = {
> + .type = TYPE_S3C2412,
> +};
> +
> +static const struct s3c24XX_nand_devtype_data s3c2440_nand_devtype_data = {
> + .type = TYPE_S3C2440,
> +};
> +
> /* conversion functions */
>
> static struct s3c2410_nand_mtd *s3c2410_nand_mtd_toours(struct mtd_info *mtd)
> @@ -794,6 +812,34 @@ static int s3c2410_nand_add_partition(struct
> s3c2410_nand_info *info,
> return -ENODEV;
> }
>
> +static int s3c2410_nand_setup_data_interface(struct mtd_info *mtd,
> + const struct nand_data_interface
> *conf,
> + bool check_only)
> +{
> + struct s3c2410_nand_info *info = s3c2410_nand_mtd_toinfo(mtd);
> + struct s3c2410_platform_nand *pdata = info->platform;
> + struct device_node *np = info->device->of_node;
> + const struct nand_sdr_timings *timings;
> + int tacls;
> +
> + /* auto-detect timings when booting with a device tree */
> + if (np) {
That's not really dependent on the use of DT, but I understand why you
want to keep it unchanged for users who did not switch to DT.
Instead of testing the np value here, I'd recommend that you
conditionally assign chip->setup_data_interface to
s3c2410_nand_setup_data_interface in s3c2410_nand_init_chip().
Can you also explain in more details in the comment why you don't want
to do it for non-DT configs (keep behavior unchanged for legacy boards)?
> + timings = nand_get_sdr_timings(conf);
> + if (IS_ERR(timings))
> + return -ENOTSUPP;
> +
> + tacls = timings->tCLS_min - timings->tWP_min;
> + if (tacls < 0)
> + tacls = 0;
> +
> + pdata->tacls = DIV_ROUND_UP(tacls, 1000);
> + pdata->twrph0 = DIV_ROUND_UP(timings->tWP_min, 1000);
> + pdata->twrph1 = DIV_ROUND_UP(timings->tCLH_min, 1000);
> + }
> +
> + return 0;
> +}
