NFC: mei: Add a common mei bus API for NFC drivers

This isolates the common code that is required to use an mei bus nfc
device from an NFC HCI drivers. This prepares for future drivers for
NFC chips connected behind an Intel Management Engine controller.
The microread_mei HCI driver is also modified to use that common code.

Signed-off-by: Eric Lapuyade <eric.lapuyade@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 9 insertions, 130 deletions

diff --git a/drivers/nfc/microread/mei.c b/drivers/nfc/microread/mei.c
index ca33ae193935..1ad044dce7b6 100644
--- a/drivers/nfc/microread/mei.c
+++ b/drivers/nfc/microread/mei.c
@@ -19,151 +19,31 @@
  */
 
 #include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/interrupt.h>
-#include <linux/gpio.h>
-#include <linux/mei_cl_bus.h>
-
+#include <linux/mod_devicetable.h>
 #include <linux/nfc.h>
 #include <net/nfc/hci.h>
 #include <net/nfc/llc.h>
 
+#include "../mei_phy.h"
 #include "microread.h"
 
 #define MICROREAD_DRIVER_NAME "microread"
 
-struct mei_nfc_hdr {
-	u8 cmd;
-	u8 status;
-	u16 req_id;
-	u32 reserved;
-	u16 data_size;
-} __attribute__((packed));
-
-#define MEI_NFC_HEADER_SIZE 10
-#define MEI_NFC_MAX_HCI_PAYLOAD 300
-#define MEI_NFC_MAX_READ (MEI_NFC_HEADER_SIZE + MEI_NFC_MAX_HCI_PAYLOAD)
-
-struct microread_mei_phy {
-	struct mei_cl_device *device;
-	struct nfc_hci_dev *hdev;
-
-	int powered;
-
-	int hard_fault;		/*
-				 * < 0 if hardware error occured (e.g. i2c err)
-				 * and prevents normal operation.
-				 */
-};
-
-#define MEI_DUMP_SKB_IN(info, skb)					\
-do {								\
-	pr_debug("%s:\n", info);				\
-	print_hex_dump(KERN_DEBUG, "mei in : ", DUMP_PREFIX_OFFSET,	\
-		       16, 1, (skb)->data, (skb)->len, 0);	\
-} while (0)
-
-#define MEI_DUMP_SKB_OUT(info, skb)					\
-do {								\
-	pr_debug("%s:\n", info);				\
-	print_hex_dump(KERN_DEBUG, "mei out: ", DUMP_PREFIX_OFFSET,	\
-		       16, 1, (skb)->data, (skb)->len, 0);	\
-} while (0)
-
-static int microread_mei_enable(void *phy_id)
-{
-	struct microread_mei_phy *phy = phy_id;
-
-	pr_info(DRIVER_DESC ": %s\n", __func__);
-
-	phy->powered = 1;
-
-	return 0;
-}
-
-static void microread_mei_disable(void *phy_id)
-{
-	struct microread_mei_phy *phy = phy_id;
-
-	pr_info(DRIVER_DESC ": %s\n", __func__);
-
-	phy->powered = 0;
-}
-
-/*
- * Writing a frame must not return the number of written bytes.
- * It must return either zero for success, or <0 for error.
- * In addition, it must not alter the skb
- */
-static int microread_mei_write(void *phy_id, struct sk_buff *skb)
-{
-	struct microread_mei_phy *phy = phy_id;
-	int r;
-
-	MEI_DUMP_SKB_OUT("mei frame sent", skb);
-
-	r = mei_cl_send(phy->device, skb->data, skb->len);
-	if (r > 0)
-		r = 0;
-
-	return r;
-}
-
-static void microread_event_cb(struct mei_cl_device *device, u32 events,
-			       void *context)
-{
-	struct microread_mei_phy *phy = context;
-
-	if (phy->hard_fault != 0)
-		return;
-
-	if (events & BIT(MEI_CL_EVENT_RX)) {
-		struct sk_buff *skb;
-		int reply_size;
-
-		skb = alloc_skb(MEI_NFC_MAX_READ, GFP_KERNEL);
-		if (!skb)
-			return;
-
-		reply_size = mei_cl_recv(device, skb->data, MEI_NFC_MAX_READ);
-		if (reply_size < MEI_NFC_HEADER_SIZE) {
-			kfree(skb);
-			return;
-		}
-
-		skb_put(skb, reply_size);
-		skb_pull(skb, MEI_NFC_HEADER_SIZE);
-
-		MEI_DUMP_SKB_IN("mei frame read", skb);
-
-		nfc_hci_recv_frame(phy->hdev, skb);
-	}
-}
-
-static struct nfc_phy_ops mei_phy_ops = {
-	.write = microread_mei_write,
-	.enable = microread_mei_enable,
-	.disable = microread_mei_disable,
-};
-
 static int microread_mei_probe(struct mei_cl_device *device,
 			       const struct mei_cl_device_id *id)
 {
-	struct microread_mei_phy *phy;
+	struct nfc_mei_phy *phy;
 	int r;
 
 	pr_info("Probing NFC microread\n");
 
-	phy = kzalloc(sizeof(struct microread_mei_phy), GFP_KERNEL);
+	phy = nfc_mei_phy_alloc(device);
 	if (!phy) {
 		pr_err("Cannot allocate memory for microread mei phy.\n");
 		return -ENOMEM;
 	}
 
-	phy->device = device;
-	mei_cl_set_drvdata(device, phy);
-
-	r = mei_cl_register_event_cb(device, microread_event_cb, phy);
+	r = mei_cl_register_event_cb(device, nfc_mei_event_cb, phy);
 	if (r) {
 		pr_err(MICROREAD_DRIVER_NAME ": event cb registration failed\n");
 		goto err_out;
@@ -178,23 +58,22 @@ static int microread_mei_probe(struct mei_cl_device *device,
 	return 0;
 
 err_out:
-	kfree(phy);
+	nfc_mei_phy_free(phy);
 
 	return r;
 }
 
 static int microread_mei_remove(struct mei_cl_device *device)
 {
-	struct microread_mei_phy *phy = mei_cl_get_drvdata(device);
+	struct nfc_mei_phy *phy = mei_cl_get_drvdata(device);
 
 	pr_info("Removing microread\n");
 
 	microread_remove(phy->hdev);
 
-	if (phy->powered)
-		microread_mei_disable(phy);
+	nfc_mei_phy_disable(phy);
 
-	kfree(phy);
+	nfc_mei_phy_free(phy);
 
 	return 0;
 }