[PATCH v2 2/2] bus: mhi: host: Drop the auto_queue support

From: Manivannan Sadhasivam <[email protected]>

Now that the only user of the 'auto_queue' feature, (QRTR) has been
converted to manage the buffers on its own, drop the code related to it.

Reviewed-by: Loic Poulain <[email protected]>
Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
 drivers/bus/mhi/host/init.c     | 10 -----
 drivers/bus/mhi/host/internal.h |  3 --
 drivers/bus/mhi/host/main.c     | 81 +----------------------------------------
 include/linux/mhi.h             | 14 -------
 4 files changed, 2 insertions(+), 106 deletions(-)

diff --git a/drivers/bus/mhi/host/init.c b/drivers/bus/mhi/host/init.c
index 099be8dd1900..b020a6489c07 100644
--- a/drivers/bus/mhi/host/init.c
+++ b/drivers/bus/mhi/host/init.c
@@ -841,18 +841,8 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
 		mhi_chan->lpm_notify = ch_cfg->lpm_notify;
 		mhi_chan->offload_ch = ch_cfg->offload_channel;
 		mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
-		mhi_chan->pre_alloc = ch_cfg->auto_queue;
 		mhi_chan->wake_capable = ch_cfg->wake_capable;
 
-		/*
-		 * If MHI host allocates buffers, then the channel direction
-		 * should be DMA_FROM_DEVICE
-		 */
-		if (mhi_chan->pre_alloc && mhi_chan->dir != DMA_FROM_DEVICE) {
-			dev_err(dev, "Invalid channel configuration\n");
-			goto error_chan_cfg;
-		}
-
 		/*
 		 * Bi-directional and direction less channel must be an
 		 * offload channel
diff --git a/drivers/bus/mhi/host/internal.h b/drivers/bus/mhi/host/internal.h
index 7937bb1f742c..7b0ee5e3a12d 100644
--- a/drivers/bus/mhi/host/internal.h
+++ b/drivers/bus/mhi/host/internal.h
@@ -286,7 +286,6 @@ struct mhi_chan {
 	bool lpm_notify;
 	bool configured;
 	bool offload_ch;
-	bool pre_alloc;
 	bool wake_capable;
 };
 
@@ -389,8 +388,6 @@ int mhi_rddm_prepare(struct mhi_controller *mhi_cntrl,
 		      struct image_info *img_info);
 void mhi_fw_load_handler(struct mhi_controller *mhi_cntrl);
 
-/* Automatically allocate and queue inbound buffers */
-#define MHI_CH_INBOUND_ALLOC_BUFS BIT(0)
 int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl,
 		       struct mhi_chan *mhi_chan);
 void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl,
diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c
index 861551274319..53c0ffe30070 100644
--- a/drivers/bus/mhi/host/main.c
+++ b/drivers/bus/mhi/host/main.c
@@ -664,23 +664,6 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl,
 				mhi_cntrl->runtime_put(mhi_cntrl);
 			}
 
-			/*
-			 * Recycle the buffer if buffer is pre-allocated,
-			 * if there is an error, not much we can do apart
-			 * from dropping the packet
-			 */
-			if (mhi_chan->pre_alloc) {
-				if (mhi_queue_buf(mhi_chan->mhi_dev,
-						  mhi_chan->dir,
-						  buf_info->cb_buf,
-						  buf_info->len, MHI_EOT)) {
-					dev_err(dev,
-						"Error recycling buffer for chan:%d\n",
-						mhi_chan->chan);
-					kfree(buf_info->cb_buf);
-				}
-			}
-
 			read_lock_bh(&mhi_chan->lock);
 		}
 		break;
@@ -1177,17 +1160,12 @@ static int mhi_queue(struct mhi_device *mhi_dev, struct mhi_buf_info *buf_info,
 int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
 		  struct sk_buff *skb, size_t len, enum mhi_flags mflags)
 {
-	struct mhi_chan *mhi_chan = (dir == DMA_TO_DEVICE) ? mhi_dev->ul_chan :
-							     mhi_dev->dl_chan;
 	struct mhi_buf_info buf_info = { };
 
 	buf_info.v_addr = skb->data;
 	buf_info.cb_buf = skb;
 	buf_info.len = len;
 
-	if (unlikely(mhi_chan->pre_alloc))
-		return -EINVAL;
-
 	return mhi_queue(mhi_dev, &buf_info, dir, mflags);
 }
 EXPORT_SYMBOL_GPL(mhi_queue_skb);
@@ -1472,45 +1450,6 @@ static int mhi_prepare_channel(struct mhi_controller *mhi_cntrl,
 	if (ret)
 		goto error_pm_state;
 
-	if (mhi_chan->dir == DMA_FROM_DEVICE)
-		mhi_chan->pre_alloc = !!(flags & MHI_CH_INBOUND_ALLOC_BUFS);
-
-	/* Pre-allocate buffer for xfer ring */
-	if (mhi_chan->pre_alloc) {
-		int nr_el = get_nr_avail_ring_elements(mhi_cntrl,
-						       &mhi_chan->tre_ring);
-		size_t len = mhi_cntrl->buffer_len;
-
-		while (nr_el--) {
-			void *buf;
-			struct mhi_buf_info info = { };
-
-			buf = kmalloc(len, GFP_KERNEL);
-			if (!buf) {
-				ret = -ENOMEM;
-				goto error_pre_alloc;
-			}
-
-			/* Prepare transfer descriptors */
-			info.v_addr = buf;
-			info.cb_buf = buf;
-			info.len = len;
-			ret = mhi_gen_tre(mhi_cntrl, mhi_chan, &info, MHI_EOT);
-			if (ret) {
-				kfree(buf);
-				goto error_pre_alloc;
-			}
-		}
-
-		read_lock_bh(&mhi_cntrl->pm_lock);
-		if (MHI_DB_ACCESS_VALID(mhi_cntrl)) {
-			read_lock_irq(&mhi_chan->lock);
-			mhi_ring_chan_db(mhi_cntrl, mhi_chan);
-			read_unlock_irq(&mhi_chan->lock);
-		}
-		read_unlock_bh(&mhi_cntrl->pm_lock);
-	}
-
 	mutex_unlock(&mhi_chan->mutex);
 
 	return 0;
@@ -1522,12 +1461,6 @@ static int mhi_prepare_channel(struct mhi_controller *mhi_cntrl,
 error_init_chan:
 	mutex_unlock(&mhi_chan->mutex);
 
-	return ret;
-
-error_pre_alloc:
-	mutex_unlock(&mhi_chan->mutex);
-	mhi_unprepare_channel(mhi_cntrl, mhi_chan);
-
 	return ret;
 }
 
@@ -1600,12 +1533,8 @@ static void mhi_reset_data_chan(struct mhi_controller *mhi_cntrl,
 		mhi_del_ring_element(mhi_cntrl, buf_ring);
 		mhi_del_ring_element(mhi_cntrl, tre_ring);
 
-		if (mhi_chan->pre_alloc) {
-			kfree(buf_info->cb_buf);
-		} else {
-			result.buf_addr = buf_info->cb_buf;
-			mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
-		}
+		result.buf_addr = buf_info->cb_buf;
+		mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result);
 	}
 }
 
@@ -1666,12 +1595,6 @@ int mhi_prepare_for_transfer(struct mhi_device *mhi_dev)
 }
 EXPORT_SYMBOL_GPL(mhi_prepare_for_transfer);
 
-int mhi_prepare_for_transfer_autoqueue(struct mhi_device *mhi_dev)
-{
-	return __mhi_prepare_for_transfer(mhi_dev, MHI_CH_INBOUND_ALLOC_BUFS);
-}
-EXPORT_SYMBOL_GPL(mhi_prepare_for_transfer_autoqueue);
-
 void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev)
 {
 	struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl;
diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index dd372b0123a6..88ccb3e14f48 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -215,7 +215,6 @@ enum mhi_db_brst_mode {
  * @lpm_notify: The channel master requires low power mode notifications
  * @offload_channel: The client manages the channel completely
  * @doorbell_mode_switch: Channel switches to doorbell mode on M0 transition
- * @auto_queue: Framework will automatically queue buffers for DL traffic
  * @wake-capable: Channel capable of waking up the system
  */
 struct mhi_channel_config {
@@ -232,7 +231,6 @@ struct mhi_channel_config {
 	bool lpm_notify;
 	bool offload_channel;
 	bool doorbell_mode_switch;
-	bool auto_queue;
 	bool wake_capable;
 };
 
@@ -743,18 +741,6 @@ void mhi_device_put(struct mhi_device *mhi_dev);
  */
 int mhi_prepare_for_transfer(struct mhi_device *mhi_dev);
 
-/**
- * mhi_prepare_for_transfer_autoqueue - Setup UL and DL channels with auto queue
- *                                      buffers for DL traffic
- * @mhi_dev: Device associated with the channels
- *
- * Allocate and initialize the channel context and also issue the START channel
- * command to both channels. Channels can be started only if both host and
- * device execution environments match and channels are in a DISABLED state.
- * The MHI core will automatically allocate and queue buffers for the DL traffic.
- */
-int mhi_prepare_for_transfer_autoqueue(struct mhi_device *mhi_dev);
-
 /**
  * mhi_unprepare_from_transfer - Reset UL and DL channels for data transfer.
  *                               Issue the RESET channel command and let the

-- 
2.48.1