ath10k: add diag_read() to hif ops

diag_read() is used for reading from firmware memory via the diagnose window.
First user will be cal_data debugfs file.

To serialise diagnostic window access and make it safe to use while firmware is
running take ce_lock both in ath10k_pci_diag_write_mem() and
ath10k_pci_diag_read_mem(). Because of that all the CE calls had to be changed
to _nolock variants.

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c
index 8319d83..ae961c6 100644
--- a/drivers/net/wireless/ath/ath10k/pci.c
+++ b/drivers/net/wireless/ath/ath10k/pci.c
@@ -485,6 +485,8 @@
 	void *data_buf = NULL;
 	int i;
 
+	spin_lock_bh(&ar_pci->ce_lock);
+
 	ce_diag = ar_pci->ce_diag;
 
 	/*
@@ -511,7 +513,7 @@
 		nbytes = min_t(unsigned int, remaining_bytes,
 			       DIAG_TRANSFER_LIMIT);
 
-		ret = ath10k_ce_rx_post_buf(ce_diag, NULL, ce_data);
+		ret = __ath10k_ce_rx_post_buf(ce_diag, NULL, ce_data);
 		if (ret != 0)
 			goto done;
 
@@ -527,15 +529,15 @@
 		address = TARG_CPU_SPACE_TO_CE_SPACE(ar, ar_pci->mem,
 						     address);
 
-		ret = ath10k_ce_send(ce_diag, NULL, (u32)address, nbytes, 0,
-				     0);
+		ret = ath10k_ce_send_nolock(ce_diag, NULL, (u32)address, nbytes, 0,
+					    0);
 		if (ret)
 			goto done;
 
 		i = 0;
-		while (ath10k_ce_completed_send_next(ce_diag, NULL, &buf,
-						     &completed_nbytes,
-						     &id) != 0) {
+		while (ath10k_ce_completed_send_next_nolock(ce_diag, NULL, &buf,
+							    &completed_nbytes,
+							    &id) != 0) {
 			mdelay(1);
 			if (i++ > DIAG_ACCESS_CE_TIMEOUT_MS) {
 				ret = -EBUSY;
@@ -554,9 +556,9 @@
 		}
 
 		i = 0;
-		while (ath10k_ce_completed_recv_next(ce_diag, NULL, &buf,
-						     &completed_nbytes,
-						     &id, &flags) != 0) {
+		while (ath10k_ce_completed_recv_next_nolock(ce_diag, NULL, &buf,
+							    &completed_nbytes,
+							    &id, &flags) != 0) {
 			mdelay(1);
 
 			if (i++ > DIAG_ACCESS_CE_TIMEOUT_MS) {
@@ -591,6 +593,8 @@
 		dma_free_coherent(ar->dev, orig_nbytes, data_buf,
 				  ce_data_base);
 
+	spin_unlock_bh(&ar_pci->ce_lock);
+
 	return ret;
 }
 
@@ -648,6 +652,8 @@
 	dma_addr_t ce_data_base = 0;
 	int i;
 
+	spin_lock_bh(&ar_pci->ce_lock);
+
 	ce_diag = ar_pci->ce_diag;
 
 	/*
@@ -688,7 +694,7 @@
 		nbytes = min_t(int, remaining_bytes, DIAG_TRANSFER_LIMIT);
 
 		/* Set up to receive directly into Target(!) address */
-		ret = ath10k_ce_rx_post_buf(ce_diag, NULL, address);
+		ret = __ath10k_ce_rx_post_buf(ce_diag, NULL, address);
 		if (ret != 0)
 			goto done;
 
@@ -696,15 +702,15 @@
 		 * Request CE to send caller-supplied data that
 		 * was copied to bounce buffer to Target(!) address.
 		 */
-		ret = ath10k_ce_send(ce_diag, NULL, (u32)ce_data,
-				     nbytes, 0, 0);
+		ret = ath10k_ce_send_nolock(ce_diag, NULL, (u32)ce_data,
+					    nbytes, 0, 0);
 		if (ret != 0)
 			goto done;
 
 		i = 0;
-		while (ath10k_ce_completed_send_next(ce_diag, NULL, &buf,
-						     &completed_nbytes,
-						     &id) != 0) {
+		while (ath10k_ce_completed_send_next_nolock(ce_diag, NULL, &buf,
+							    &completed_nbytes,
+							    &id) != 0) {
 			mdelay(1);
 
 			if (i++ > DIAG_ACCESS_CE_TIMEOUT_MS) {
@@ -724,9 +730,9 @@
 		}
 
 		i = 0;
-		while (ath10k_ce_completed_recv_next(ce_diag, NULL, &buf,
-						     &completed_nbytes,
-						     &id, &flags) != 0) {
+		while (ath10k_ce_completed_recv_next_nolock(ce_diag, NULL, &buf,
+							    &completed_nbytes,
+							    &id, &flags) != 0) {
 			mdelay(1);
 
 			if (i++ > DIAG_ACCESS_CE_TIMEOUT_MS) {
@@ -760,6 +766,8 @@
 		ath10k_warn(ar, "failed to write diag value at 0x%x: %d\n",
 			    address, ret);
 
+	spin_unlock_bh(&ar_pci->ce_lock);
+
 	return ret;
 }
 
@@ -942,6 +950,12 @@
 	return err;
 }
 
+static int ath10k_pci_hif_diag_read(struct ath10k *ar, u32 address, void *buf,
+				    size_t buf_len)
+{
+	return ath10k_pci_diag_read_mem(ar, address, buf, buf_len);
+}
+
 static u16 ath10k_pci_hif_get_free_queue_number(struct ath10k *ar, u8 pipe)
 {
 	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
@@ -1927,6 +1941,7 @@
 
 static const struct ath10k_hif_ops ath10k_pci_hif_ops = {
 	.tx_sg			= ath10k_pci_hif_tx_sg,
+	.diag_read		= ath10k_pci_hif_diag_read,
 	.exchange_bmi_msg	= ath10k_pci_hif_exchange_bmi_msg,
 	.start			= ath10k_pci_hif_start,
 	.stop			= ath10k_pci_hif_stop,