nvmem: imx-ocotp: add support for post processing

Add .cell_post_process callback for imx-ocotp to deal with MAC address,
since MAC address need to be reversed byte for some i.MX SoCs.

Tested-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20211013131957.30271-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index 08f4132..14284e8 100644 (file)
--- a/drivers/nvmem/imx-ocotp.c
+++ b/drivers/nvmem/imx-ocotp.c
@@ -97,6 +97,7 @@ struct ocotp_params {
        unsigned int bank_address_words;
        void (*set_timing)(struct ocotp_priv *priv);
        struct ocotp_ctrl_reg ctrl;
+       bool reverse_mac_address;
 };
 
 static int imx_ocotp_wait_for_busy(struct ocotp_priv *priv, u32 flags)
@@ -221,6 +222,25 @@ read_end:
        return ret;
 }
 
+static int imx_ocotp_cell_pp(void *context, const char *id, unsigned int offset,
+                            void *data, size_t bytes)
+{
+       struct ocotp_priv *priv = context;
+
+       /* Deal with some post processing of nvmem cell data */
+       if (id && !strcmp(id, "mac-address")) {
+               if (priv->params->reverse_mac_address) {
+                       u8 *buf = data;
+                       int i;
+
+                       for (i = 0; i < bytes/2; i++)
+                               swap(buf[i], buf[bytes - i - 1]);
+               }
+       }
+
+       return 0;
+}
+
 static void imx_ocotp_set_imx6_timing(struct ocotp_priv *priv)
 {
        unsigned long clk_rate;
@@ -468,6 +488,7 @@ static struct nvmem_config imx_ocotp_nvmem_config = {
        .stride = 1,
        .reg_read = imx_ocotp_read,
        .reg_write = imx_ocotp_write,
+       .cell_post_process = imx_ocotp_cell_pp,
 };
 
 static const struct ocotp_params imx6q_params = {
@@ -530,6 +551,7 @@ static const struct ocotp_params imx8mq_params = {
        .bank_address_words = 0,
        .set_timing = imx_ocotp_set_imx6_timing,
        .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
+       .reverse_mac_address = true,
 };
 
 static const struct ocotp_params imx8mm_params = {
@@ -537,6 +559,7 @@ static const struct ocotp_params imx8mm_params = {
        .bank_address_words = 0,
        .set_timing = imx_ocotp_set_imx6_timing,
        .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
+       .reverse_mac_address = true,
 };
 
 static const struct ocotp_params imx8mn_params = {
@@ -544,6 +567,7 @@ static const struct ocotp_params imx8mn_params = {
        .bank_address_words = 0,
        .set_timing = imx_ocotp_set_imx6_timing,
        .ctrl = IMX_OCOTP_BM_CTRL_DEFAULT,
+       .reverse_mac_address = true,
 };
 
 static const struct ocotp_params imx8mp_params = {
@@ -551,6 +575,7 @@ static const struct ocotp_params imx8mp_params = {
        .bank_address_words = 0,
        .set_timing = imx_ocotp_set_imx6_timing,
        .ctrl = IMX_OCOTP_BM_CTRL_8MP,
+       .reverse_mac_address = true,
 };
 
 static const struct of_device_id imx_ocotp_dt_ids[] = {