[PATCH 3/3] nvmem: imx-ocotp: add support for post processing

From: Srinivas Kandagatla
Date: Wed Oct 06 2021 - 10:47:51 EST


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.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
---
drivers/nvmem/imx-ocotp.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/nvmem/imx-ocotp.c b/drivers/nvmem/imx-ocotp.c
index 08f41328cc71..89fd4d3eb649 100644
--- 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 @@ static int imx_ocotp_read(void *context, unsigned int offset,
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 (!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[] = {
--
2.21.0