From: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
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.
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
---
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
--
2.48.1On Wed, Dec 17, 2025 at 6:17 PM Manivannan Sadhasivam via B4 Relay
<devnull+manivannan.sadhasivam.oss.qualcomm.com@kernel.org> wrote:
>
> From: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
>
> 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.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@oss.qualcomm.com>
Reviewed-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
> ---
> 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
>
>
© 2016 - 2026 Red Hat, Inc.