nfc: fdp: constify several pointers

Several functions do not modify pointed data so arguments and local
variables can be const for correctness and safety.  This allows also
making file-scope nci_core_get_config_otp_ram_version array const.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/nfc/fdp/fdp.c

@@ -52,7 +52,7 @@ struct fdp_nci_info {
 	u32 limited_otp_version;
 	u8 key_index;
 
-	u8 *fw_vsc_cfg;
+	const u8 *fw_vsc_cfg;
 	u8 clock_type;
 	u32 clock_freq;
 
@@ -65,7 +65,7 @@ struct fdp_nci_info {
 	wait_queue_head_t setup_wq;
 };
 
-static u8 nci_core_get_config_otp_ram_version[5] = {
+static const u8 nci_core_get_config_otp_ram_version[5] = {
 	0x04,
 	NCI_PARAM_ID_FW_RAM_VERSION,
 	NCI_PARAM_ID_FW_OTP_VERSION,
@@ -111,7 +111,7 @@ static inline int fdp_nci_patch_cmd(struct nci_dev *ndev, u8 type)
 }
 
 static inline int fdp_nci_set_production_data(struct nci_dev *ndev, u8 len,
-					      char *data)
+					      const char *data)
 {
 	return nci_prop_cmd(ndev, NCI_OP_PROP_SET_PDATA_OID, len, data);
 }
@@ -236,7 +236,7 @@ static int fdp_nci_send_patch(struct nci_dev *ndev, u8 conn_id, u8 type)
 
 static int fdp_nci_open(struct nci_dev *ndev)
 {
-	struct fdp_nci_info *info = nci_get_drvdata(ndev);
+	const struct fdp_nci_info *info = nci_get_drvdata(ndev);
 
 	return info->phy_ops->enable(info->phy);
 }
@@ -260,7 +260,7 @@ static int fdp_nci_request_firmware(struct nci_dev *ndev)
 {
 	struct fdp_nci_info *info = nci_get_drvdata(ndev);
 	struct device *dev = &info->phy->i2c_dev->dev;
-	u8 *data;
+	const u8 *data;
 	int r;
 
 	r = request_firmware(&info->ram_patch, FDP_RAM_PATCH_NAME, dev);
@@ -269,7 +269,7 @@ static int fdp_nci_request_firmware(struct nci_dev *ndev)
 		return r;
 	}
 
-	data = (u8 *) info->ram_patch->data;
+	data = info->ram_patch->data;
 	info->ram_patch_version =
 		data[FDP_FW_HEADER_SIZE] |
 		(data[FDP_FW_HEADER_SIZE + 1] << 8) |
@@ -610,9 +610,9 @@ static int fdp_nci_core_get_config_rsp_packet(struct nci_dev *ndev,
 {
 	struct fdp_nci_info *info = nci_get_drvdata(ndev);
 	struct device *dev = &info->phy->i2c_dev->dev;
-	struct nci_core_get_config_rsp *rsp = (void *) skb->data;
+	const struct nci_core_get_config_rsp *rsp = (void *) skb->data;
 	unsigned int i;
-	u8 *p;
+	const u8 *p;
 
 	if (rsp->status == NCI_STATUS_OK) {
 
@@ -691,7 +691,7 @@ static const struct nci_ops nci_ops = {
 int fdp_nci_probe(struct fdp_i2c_phy *phy, const struct nfc_phy_ops *phy_ops,
 			struct nci_dev **ndevp, int tx_headroom,
 			int tx_tailroom, u8 clock_type, u32 clock_freq,
-			u8 *fw_vsc_cfg)
+			const u8 *fw_vsc_cfg)
 {
 	struct device *dev = &phy->i2c_dev->dev;
 	struct fdp_nci_info *info;

drivers/nfc/fdp/fdp.h

@@ -23,7 +23,7 @@ struct fdp_i2c_phy {
 
 int fdp_nci_probe(struct fdp_i2c_phy *phy, const struct nfc_phy_ops *phy_ops,
 		  struct nci_dev **ndev, int tx_headroom, int tx_tailroom,
-		  u8 clock_type, u32 clock_freq, u8 *fw_vsc_cfg);
+		  u8 clock_type, u32 clock_freq, const u8 *fw_vsc_cfg);
 void fdp_nci_remove(struct nci_dev *ndev);
 
 #endif /* __LOCAL_FDP_H_ */

drivers/nfc/fdp/i2c.c

@@ -36,7 +36,7 @@
 	print_hex_dump(KERN_DEBUG, prefix": ", DUMP_PREFIX_OFFSET,	\
 		       16, 1, (skb)->data, (skb)->len, 0)
 
-static void fdp_nci_i2c_reset(struct fdp_i2c_phy *phy)
+static void fdp_nci_i2c_reset(const struct fdp_i2c_phy *phy)
 {
 	/* Reset RST/WakeUP for at least 100 micro-second */
 	gpiod_set_value_cansleep(phy->power_gpio, FDP_POWER_OFF);
@@ -47,7 +47,7 @@ static void fdp_nci_i2c_reset(struct fdp_i2c_phy *phy)
 
 static int fdp_nci_i2c_enable(void *phy_id)
 {
-	struct fdp_i2c_phy *phy = phy_id;
+	const struct fdp_i2c_phy *phy = phy_id;
 
 	fdp_nci_i2c_reset(phy);
 
@@ -56,7 +56,7 @@ static int fdp_nci_i2c_enable(void *phy_id)
 
 static void fdp_nci_i2c_disable(void *phy_id)
 {
-	struct fdp_i2c_phy *phy = phy_id;
+	const struct fdp_i2c_phy *phy = phy_id;
 
 	fdp_nci_i2c_reset(phy);
 }