by andrew-ct chen

[permalink] [raw]

Subject: Re: [PATCH 08/12] nvmem: mtk-efuse: remove nvmem regmap dependency

Hi Srinivas,

On Sun, 2016-04-24 at 20:28 +0100, Srinivas Kandagatla wrote:
> This patch moves to nvmem support in the driver to use callback
> instead of regmap.
>
> Signed-off-by: Srinivas Kandagatla <[email protected]>
> ---

Thanks for the patch. It works on our platform. This driver doesn't
support "efuse write". I will send another patch for fixing this.

Acked-by: Andrew-CT Chen <[email protected]>

Andrew

> drivers/nvmem/Kconfig | 1 -
> drivers/nvmem/mtk-efuse.c | 47 ++++++++++++++++++++++++++++++++---------------
> 2 files changed, 32 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
> index 377bc21..c158712 100644
> --- a/drivers/nvmem/Kconfig
> +++ b/drivers/nvmem/Kconfig
> @@ -48,7 +48,6 @@ config NVMEM_MXS_OCOTP
> config MTK_EFUSE
> tristate "Mediatek SoCs EFUSE support"
> depends on ARCH_MEDIATEK || COMPILE_TEST
> - select REGMAP_MMIO
> help
> This is a driver to access hardware related data like sensor
> calibration, HDMI impedance etc.
> diff --git a/drivers/nvmem/mtk-efuse.c b/drivers/nvmem/mtk-efuse.c
> index 9c49369..32fd572 100644
> --- a/drivers/nvmem/mtk-efuse.c
> +++ b/drivers/nvmem/mtk-efuse.c
> @@ -14,15 +14,35 @@
>
> #include <linux/device.h>
> #include <linux/module.h>
> +#include <linux/io.h>
> #include <linux/nvmem-provider.h>
> #include <linux/platform_device.h>
> -#include <linux/regmap.h>
>
> -static struct regmap_config mtk_regmap_config = {
> - .reg_bits = 32,
> - .val_bits = 32,
> - .reg_stride = 4,
> -};
> +static int mtk_reg_read(void *context,
> + unsigned int reg, void *_val, size_t bytes)
> +{
> + void __iomem *base = context;
> + u32 *val = _val;
> + int i = 0, words = bytes / 4;
> +
> + while (words--)
> + *val++ = readl(base + reg + (i++ * 4));
> +
> + return 0;
> +}
> +
> +static int mtk_reg_write(void *context,
> + unsigned int reg, void *_val, size_t bytes)
> +{
> + void __iomem *base = context;
> + u32 *val = _val;
> + int i = 0, words = bytes / 4;
> +
> + while (words--)
> + writel(*val++, base + reg + (i++ * 4));
> +
> + return 0;
> +}
>
> static int mtk_efuse_probe(struct platform_device *pdev)
> {
> @@ -30,7 +50,6 @@ static int mtk_efuse_probe(struct platform_device *pdev)
> struct resource *res;
> struct nvmem_device *nvmem;
> struct nvmem_config *econfig;
> - struct regmap *regmap;
> void __iomem *base;
>
> res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> @@ -42,14 +61,12 @@ static int mtk_efuse_probe(struct platform_device *pdev)
> if (!econfig)
> return -ENOMEM;
>
> - mtk_regmap_config.max_register = resource_size(res) - 1;
> -
> - regmap = devm_regmap_init_mmio(dev, base, &mtk_regmap_config);
> - if (IS_ERR(regmap)) {
> - dev_err(dev, "regmap init failed\n");
> - return PTR_ERR(regmap);
> - }
> -
> + econfig->stride = 4;
> + econfig->word_size = 4;
> + econfig->reg_read = mtk_reg_read;
> + econfig->reg_write = mtk_reg_write;
> + econfig->size = resource_size(res);
> + econfig->priv = base;
> econfig->dev = dev;
> econfig->owner = THIS_MODULE;
> nvmem = nvmem_register(econfig);

2016-04-28 06:51:45

by Stefan Wahren

[permalink] [raw]

Subject: Re: [PATCH 11/12] nvmem: mxs-ocotp: remove nvmem regmap dependency

Hi Srinivas,

Am 24.04.2016 um 21:28 schrieb Srinivas Kandagatla:
> This patch moves to nvmem support in the driver to use callback
> instead of regmap.
>
> Signed-off-by: Srinivas Kandagatla <[email protected]>
> ---
> drivers/nvmem/mxs-ocotp.c | 79 +++++++++++++----------------------------------
> 1 file changed, 21 insertions(+), 58 deletions(-)
>
> diff --git a/drivers/nvmem/mxs-ocotp.c b/drivers/nvmem/mxs-ocotp.c
> index 8ba19bb..3bf962c 100644
> --- a/drivers/nvmem/mxs-ocotp.c
> +++ b/drivers/nvmem/mxs-ocotp.c

the include of regmap.h should also be removed.

> @@ -66,11 +66,10 @@ static int mxs_ocotp_wait(struct mxs_ocotp *otp)
> return 0;
> }
>
> -static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
> - void *val, size_t val_size)
> +static int mxs_ocotp_read(void *context, unsigned int offset,
> + void *val, size_t bytes)
> {
> struct mxs_ocotp *otp = context;
> - unsigned int offset = *(u32 *)reg;
> u32 *buf = val;
> int ret;
>
> @@ -94,17 +93,16 @@ static int mxs_ocotp_read(void *context, const void *reg, size_t reg_size,
> if (ret)
> goto close_banks;
>
> - while (val_size) {
> + while (bytes) {
> if ((offset < OCOTP_DATA_OFFSET) || (offset % 16)) {
> /* fill up non-data register */
> - *buf = 0;
> + *buf++ = 0;
> } else {
> - *buf = readl(otp->base + offset);
> + *buf++ = readl(otp->base + offset);
> }
>
> - buf++;
> - val_size--;
> - offset += reg_size;
> + bytes -= 4;
> + offset += 4;

This change would also fix the buffer overflow but Stanislav's patch
should be applied before to get the fix in stable.

> }
>
> close_banks:
> @@ -117,57 +115,28 @@ disable_clk:
> return ret;
> }
>
> -static int mxs_ocotp_write(void *context, const void *data, size_t count)
> -{
> - /* We don't want to support writing */
> - return 0;
> -}
> -
> -static bool mxs_ocotp_writeable_reg(struct device *dev, unsigned int reg)
> -{
> - return false;
> -}
> -
> static struct nvmem_config ocotp_config = {
> .name = "mxs-ocotp",
> + .stride = 16,
> + .word_size = 4,
> .owner = THIS_MODULE,

.reg_read = mxs_ocotp_read,

> };
>
> -static const struct regmap_range imx23_ranges[] = {
> - regmap_reg_range(OCOTP_DATA_OFFSET, 0x210),
> -};
> -
> -static const struct regmap_access_table imx23_access = {
> - .yes_ranges = imx23_ranges,
> - .n_yes_ranges = ARRAY_SIZE(imx23_ranges),
> -};
> -
> -static const struct regmap_range imx28_ranges[] = {
> - regmap_reg_range(OCOTP_DATA_OFFSET, 0x290),
> -};
> -
> -static const struct regmap_access_table imx28_access = {
> - .yes_ranges = imx28_ranges,
> - .n_yes_ranges = ARRAY_SIZE(imx28_ranges),
> +struct imx_data {
struct mxs_data

These chips are named imx2x but the platform is mxs. Please don't ask why.
> + int max_reg;
Since nvmem_config uses "size" instead of "max_reg" we better use "size"
here, too. This avoids confusion and potential issues see below.
> };
>
> -static struct regmap_bus mxs_ocotp_bus = {
> - .read = mxs_ocotp_read,
> - .write = mxs_ocotp_write, /* make regmap_init() happy */
> - .reg_format_endian_default = REGMAP_ENDIAN_NATIVE,
> - .val_format_endian_default = REGMAP_ENDIAN_NATIVE,
> +static const struct imx_data imx23_data = {
static const struct mxs_data imx23_data
> + .max_reg = 0x210,
.size = 0x220,
> };
>
> -static struct regmap_config mxs_ocotp_config = {
> - .reg_bits = 32,
> - .val_bits = 32,
> - .reg_stride = 16,
> - .writeable_reg = mxs_ocotp_writeable_reg,
> +static const struct imx_data imx28_data = {
static const struct mxs_data imx28_data
> + .max_reg = 0x290,
.size = 0x2a0,
> };
>
> static const struct of_device_id mxs_ocotp_match[] = {
> - { .compatible = "fsl,imx23-ocotp", .data = &imx23_access },
> - { .compatible = "fsl,imx28-ocotp", .data = &imx28_access },
> + { .compatible = "fsl,imx23-ocotp", .data = &imx23_data },
> + { .compatible = "fsl,imx28-ocotp", .data = &imx23_data },
.compatible = "fsl,imx28-ocotp", .data = &imx28_data
> { /* sentinel */},
> };
> MODULE_DEVICE_TABLE(of, mxs_ocotp_match);
> @@ -175,6 +144,7 @@ MODULE_DEVICE_TABLE(of, mxs_ocotp_match);
> static int mxs_ocotp_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> + struct imx_data *data;
const struct mxs_data *data
> struct mxs_ocotp *otp;
> struct resource *res;
> const struct of_device_id *match;
> @@ -205,17 +175,10 @@ static int mxs_ocotp_probe(struct platform_device *pdev)
> return ret;
> }
>
> - access = match->data;
> - mxs_ocotp_config.rd_table = access;
> - mxs_ocotp_config.max_register = access->yes_ranges[0].range_max;
> -
> - regmap = devm_regmap_init(dev, &mxs_ocotp_bus, otp, &mxs_ocotp_config);
> - if (IS_ERR(regmap)) {
> - dev_err(dev, "regmap init failed\n");
> - ret = PTR_ERR(regmap);
> - goto err_clk;
> - }
> + data = match->data;
>
> + ocotp_config.size = data->max_reg;
data->size

Regards
Stefan
> + ocotp_config.priv = otp;
> ocotp_config.dev = dev;
> otp->nvmem = nvmem_register(&ocotp_config);
> if (IS_ERR(otp->nvmem)) {