diff --git a/ene_lpc.c b/ene_lpc.c
index 46f178329..04c17e389 100644
--- a/ene_lpc.c
+++ b/ene_lpc.c
@@ -504,7 +504,7 @@ exit:
 	return rv;
 }
 
-static struct spi_master spi_master_ene = {
+static const struct spi_master spi_master_ene = {
 	.max_data_read = 256,
 	.max_data_write = 256,
 	.command = ene_spi_send_command,
@@ -568,11 +568,10 @@ int ene_lpc_init()
 	ene_enter_flash_mode(ctx_data);
 
 	internal_buses_supported |= BUS_LPC;
-	spi_master_ene.data = ctx_data;
 
 	if (register_shutdown(ene_leave_flash_mode, ctx_data))
 		goto init_err_cleanup_exit;
-	register_spi_master(&spi_master_ene, NULL);
+	register_spi_master(&spi_master_ene, ctx_data);
 	msg_pdbg("%s: successfully initialized ene\n", __func__);
 
 	return 0;
diff --git a/mec1308.c b/mec1308.c
index 70d2a7963..3923d5bd0 100644
--- a/mec1308.c
+++ b/mec1308.c
@@ -397,7 +397,7 @@ mec1308_spi_send_command_exit:
 	return rc;
 }
 
-static struct spi_master spi_master_mec1308 = {
+static const struct spi_master spi_master_mec1308 = {
 	.max_data_read = 256,	/* FIXME: should be MAX_DATA_READ_UNLIMITED? */
 	.max_data_write = 256,	/* FIXME: should be MAX_DATA_WRITE_UNLIMITED? */
 	.command = mec1308_spi_send_command,
@@ -505,11 +505,10 @@ int mec1308_init(void)
 		goto init_err_cleanup_exit;
 
 	internal_buses_supported |= BUS_LPC;	/* for LPC <--> SPI bridging */
-	spi_master_mec1308.data = ctx_data;
 
 	if (register_shutdown(mec1308_shutdown, ctx_data))
 		goto init_err_cleanup_exit;
-	register_spi_master(&spi_master_mec1308, NULL);
+	register_spi_master(&spi_master_mec1308, ctx_data);
 	msg_pdbg("%s(): successfully initialized mec1308\n", __func__);
 
 	return 0;
diff --git a/raiden_debug_spi.c b/raiden_debug_spi.c
index c27585154..f67bbe5ec 100644
--- a/raiden_debug_spi.c
+++ b/raiden_debug_spi.c
@@ -1597,7 +1597,7 @@ loop_end:
 	data->in_ep = in_endpoint;
 	data->out_ep = out_endpoint;
 
-	spi_config->data = data;
+	spi_config->data = data; /* data is needed to configure protocol below */
 	/*
 	 * The SPI master needs to be configured based on the device connected.
 	 * Using the device protocol interrogation, we will set the limits on
@@ -1614,7 +1614,7 @@ loop_end:
 		return SPI_GENERIC_ERROR;
 	}
 
-	register_spi_master(spi_config, NULL);
+	register_spi_master(spi_config, data);
 	register_shutdown(raiden_debug_spi_shutdown, spi_config);
 
 	return 0;
diff --git a/realtek_mst_i2c_spi.c b/realtek_mst_i2c_spi.c
index f0a6dce91..95c017fa0 100644
--- a/realtek_mst_i2c_spi.c
+++ b/realtek_mst_i2c_spi.c
@@ -410,7 +410,7 @@ static int realtek_mst_i2c_spi_write_aai(struct flashctx *flash, const uint8_t *
 	return SPI_GENERIC_ERROR;
 }
 
-static struct spi_master spi_master_i2c_realtek_mst = {
+static const struct spi_master spi_master_i2c_realtek_mst = {
 	.max_data_read = 16,
 	.max_data_write = 8,
 	.command = realtek_mst_i2c_spi_send_command,
@@ -513,9 +513,7 @@ int realtek_mst_i2c_spi_init(void)
 	data->fd = fd;
 	data->reset = reset;
 	ret |= register_shutdown(realtek_mst_i2c_spi_shutdown, data);
-
-	spi_master_i2c_realtek_mst.data = data;
-	ret |= register_spi_master(&spi_master_i2c_realtek_mst, NULL);
+	ret |= register_spi_master(&spi_master_i2c_realtek_mst, data);
 
 	return ret;
 }