[PATCH 1/1] dmaengine: shdma: move shdma_chan and shdma_desc structs to private header

[PATCH 1/1] dmaengine: shdma: move shdma_chan and shdma_desc structs to private header

[Frank.Li]

From: Frank Li <Frank.Li@nxp.com>

Move struct shdma_chan and struct shdma_desc from the public header
include/linux/shdma-base.h into the driver-private header
drivers/dma/sh/shdma.h. These structs are only used internally by the
shdma driver and do not need to be exposed to external users.

Prepare to make struct dma_async_tx_descriptor private.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/sh/shdma-base.c |  2 +-
 drivers/dma/sh/shdma.h      | 80 +++++++++++++++++++++++++++++++++++++
 include/linux/shdma-base.h  | 80 +------------------------------------
 3 files changed, 83 insertions(+), 79 deletions(-)

diff --git a/drivers/dma/sh/shdma-base.c b/drivers/dma/sh/shdma-base.c
index 89a78e685b1d1..ef704a6aed233 100644
--- a/drivers/dma/sh/shdma-base.c
+++ b/drivers/dma/sh/shdma-base.c
@@ -20,7 +20,7 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
-#include "../dmaengine.h"
+#include "shdma.h"
 
 /* DMA descriptor control */
 enum shdma_desc_status {
diff --git a/drivers/dma/sh/shdma.h b/drivers/dma/sh/shdma.h
index f97d80343aea4..d66d45062e9bd 100644
--- a/drivers/dma/sh/shdma.h
+++ b/drivers/dma/sh/shdma.h
@@ -15,11 +15,32 @@
 #include <linux/interrupt.h>
 #include <linux/list.h>
 
+#include "../dmaengine.h"
+
 #define SH_DMAE_MAX_CHANNELS 20
 #define SH_DMAE_TCR_MAX 0x00FFFFFF	/* 16MB */
 
 struct device;
 
+struct shdma_chan {
+	spinlock_t chan_lock;		/* Channel operation lock */
+	struct list_head ld_queue;	/* Link descriptors queue */
+	struct list_head ld_free;	/* Free link descriptors */
+	struct dma_chan dma_chan;	/* DMA channel */
+	struct device *dev;		/* Channel device */
+	void *desc;			/* buffer for descriptor array */
+	int desc_num;			/* desc count */
+	size_t max_xfer_len;		/* max transfer length */
+	int id;				/* Raw id of this channel */
+	int irq;			/* Channel IRQ */
+	int slave_id;			/* Client ID for slave DMA */
+	int real_slave_id;		/* argument passed to filter function */
+	int hw_req;			/* DMA request line for slave DMA -
+					 * same as MID/RID, used with DT
+					 */
+	enum shdma_pm_state pm_state;
+};
+
 struct sh_dmae_chan {
 	struct shdma_chan shdma_chan;
 	const struct sh_dmae_slave_config *config; /* Slave DMA configuration */
@@ -30,6 +51,13 @@ struct sh_dmae_chan {
 	dma_addr_t slave_addr;
 };
 
+struct shdma_dev {
+	struct dma_device dma_dev;
+	struct shdma_chan **schan;
+	const struct shdma_ops *ops;
+	size_t desc_size;
+};
+
 struct sh_dmae_device {
 	struct shdma_dev shdma_dev;
 	struct sh_dmae_chan *chan[SH_DMAE_MAX_CHANNELS];
@@ -41,6 +69,58 @@ struct sh_dmae_device {
 	u32 chcr_ie_bit;
 };
 
+struct shdma_desc {
+	struct list_head node;
+	struct dma_async_tx_descriptor async_tx;
+	enum dma_transfer_direction direction;
+	size_t partial;
+	dma_cookie_t cookie;
+	int chunks;
+	int mark;
+	bool cyclic;			/* used as cyclic transfer */
+};
+
+/**
+ * struct shdma_ops - simple DMA driver operations
+ * @desc_completed:	return true, if this is the descriptor, that just has
+ *			completed (atomic)
+ * @halt_channel:	stop DMA channel operation (atomic)
+ * @channel_busy:	return true, if the channel is busy (atomic)
+ * @slave_addr:		return slave DMA address
+ * @desc_setup:		set up the hardware specific descriptor portion (atomic)
+ * @set_slave:		bind channel to a slave
+ * @setup_xfer:		configure channel hardware for operation (atomic)
+ * @start_xfer:		start the DMA transfer (atomic)
+ * @embedded_desc:	return Nth struct shdma_desc pointer from the
+ *			descriptor array
+ * @chan_irq:		process channel IRQ, return true if a transfer has
+ *			completed (atomic)
+ */
+struct shdma_ops {
+	bool (*desc_completed)(struct shdma_chan *, struct shdma_desc *);
+	void (*halt_channel)(struct shdma_chan *);
+	bool (*channel_busy)(struct shdma_chan *);
+	dma_addr_t (*slave_addr)(struct shdma_chan *);
+	int (*desc_setup)(struct shdma_chan *, struct shdma_desc *,
+			  dma_addr_t, dma_addr_t, size_t *);
+	int (*set_slave)(struct shdma_chan *, int, dma_addr_t, bool);
+	int (*setup_xfer)(struct shdma_chan *, int);
+	void (*start_xfer)(struct shdma_chan *, struct shdma_desc *);
+	struct shdma_desc *(*embedded_desc)(void *, int);
+	bool (*chan_irq)(struct shdma_chan *, int);
+	size_t (*get_partial)(struct shdma_chan *, struct shdma_desc *);
+};
+
+#define shdma_for_each_chan(c, d, i) for (i = 0, c = (d)->schan[0]; \
+				i < (d)->dma_dev.chancnt; c = (d)->schan[++i])
+
+int shdma_request_irq(struct shdma_chan *, int, unsigned long, const char *);
+bool shdma_reset(struct shdma_dev *sdev);
+void shdma_chan_probe(struct shdma_dev *sdev, struct shdma_chan *schan, int id);
+void shdma_chan_remove(struct shdma_chan *schan);
+int shdma_init(struct device *dev, struct shdma_dev *sdev, int chan_num);
+void shdma_cleanup(struct shdma_dev *sdev);
+
 struct sh_dmae_regs {
 	u32 sar; /* SAR / source address */
 	u32 dar; /* DAR / destination address */
diff --git a/include/linux/shdma-base.h b/include/linux/shdma-base.h
index b6827c06d332f..a7e6184728f8d 100644
--- a/include/linux/shdma-base.h
+++ b/include/linux/shdma-base.h
@@ -43,85 +43,9 @@ struct shdma_slave {
 	int slave_id;
 };
 
-struct shdma_desc {
-	struct list_head node;
-	struct dma_async_tx_descriptor async_tx;
-	enum dma_transfer_direction direction;
-	size_t partial;
-	dma_cookie_t cookie;
-	int chunks;
-	int mark;
-	bool cyclic;			/* used as cyclic transfer */
-};
-
-struct shdma_chan {
-	spinlock_t chan_lock;		/* Channel operation lock */
-	struct list_head ld_queue;	/* Link descriptors queue */
-	struct list_head ld_free;	/* Free link descriptors */
-	struct dma_chan dma_chan;	/* DMA channel */
-	struct device *dev;		/* Channel device */
-	void *desc;			/* buffer for descriptor array */
-	int desc_num;			/* desc count */
-	size_t max_xfer_len;		/* max transfer length */
-	int id;				/* Raw id of this channel */
-	int irq;			/* Channel IRQ */
-	int slave_id;			/* Client ID for slave DMA */
-	int real_slave_id;		/* argument passed to filter function */
-	int hw_req;			/* DMA request line for slave DMA - same
-					 * as MID/RID, used with DT */
-	enum shdma_pm_state pm_state;
-};
-
-/**
- * struct shdma_ops - simple DMA driver operations
- * @desc_completed:	return true, if this is the descriptor, that just has
- *			completed (atomic)
- * @halt_channel:	stop DMA channel operation (atomic)
- * @channel_busy:	return true, if the channel is busy (atomic)
- * @slave_addr:		return slave DMA address
- * @desc_setup:		set up the hardware specific descriptor portion (atomic)
- * @set_slave:		bind channel to a slave
- * @setup_xfer:		configure channel hardware for operation (atomic)
- * @start_xfer:		start the DMA transfer (atomic)
- * @embedded_desc:	return Nth struct shdma_desc pointer from the
- *			descriptor array
- * @chan_irq:		process channel IRQ, return true if a transfer has
- *			completed (atomic)
- */
-struct shdma_ops {
-	bool (*desc_completed)(struct shdma_chan *, struct shdma_desc *);
-	void (*halt_channel)(struct shdma_chan *);
-	bool (*channel_busy)(struct shdma_chan *);
-	dma_addr_t (*slave_addr)(struct shdma_chan *);
-	int (*desc_setup)(struct shdma_chan *, struct shdma_desc *,
-			  dma_addr_t, dma_addr_t, size_t *);
-	int (*set_slave)(struct shdma_chan *, int, dma_addr_t, bool);
-	int (*setup_xfer)(struct shdma_chan *, int);
-	void (*start_xfer)(struct shdma_chan *, struct shdma_desc *);
-	struct shdma_desc *(*embedded_desc)(void *, int);
-	bool (*chan_irq)(struct shdma_chan *, int);
-	size_t (*get_partial)(struct shdma_chan *, struct shdma_desc *);
-};
-
-struct shdma_dev {
-	struct dma_device dma_dev;
-	struct shdma_chan **schan;
-	const struct shdma_ops *ops;
-	size_t desc_size;
-};
-
-#define shdma_for_each_chan(c, d, i) for (i = 0, c = (d)->schan[0]; \
-				i < (d)->dma_dev.chancnt; c = (d)->schan[++i])
+struct shdma_chan;
+struct shdma_dev;
 
-int shdma_request_irq(struct shdma_chan *, int,
-			   unsigned long, const char *);
-bool shdma_reset(struct shdma_dev *sdev);
-void shdma_chan_probe(struct shdma_dev *sdev,
-			   struct shdma_chan *schan, int id);
-void shdma_chan_remove(struct shdma_chan *schan);
-int shdma_init(struct device *dev, struct shdma_dev *sdev,
-		    int chan_num);
-void shdma_cleanup(struct shdma_dev *sdev);
 #if IS_ENABLED(CONFIG_SH_DMAE_BASE)
 bool shdma_chan_filter(struct dma_chan *chan, void *arg);
 #else
-- 
2.43.0

Re: [PATCH 1/1] dmaengine: shdma: move shdma_chan and shdma_desc structs to private header

[Andy Shevchenko]

On Tue, Oct 13, 2026 at 04:34:23PM -0400, Frank.Li@oss.nxp.com wrote:

> Move struct shdma_chan and struct shdma_desc from the public header
> include/linux/shdma-base.h into the driver-private header
> drivers/dma/sh/shdma.h. These structs are only used internally by the
> shdma driver and do not need to be exposed to external users.
> 
> Prepare to make struct dma_async_tx_descriptor private.

This kind of changes I like!
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 1/1] dmaengine: shdma: move shdma_chan and shdma_desc structs to private header

[Randy Dunlap]

On 10/13/26 1:34 PM, Frank.Li@oss.nxp.com wrote:
> From: Frank Li <Frank.Li@nxp.com>
> 
> Move struct shdma_chan and struct shdma_desc from the public header
> include/linux/shdma-base.h into the driver-private header
> drivers/dma/sh/shdma.h. These structs are only used internally by the
> shdma driver and do not need to be exposed to external users.
> 
> Prepare to make struct dma_async_tx_descriptor private.
> 
> Signed-off-by: Frank Li <Frank.Li@nxp.com>

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Thanks.

> ---
>  drivers/dma/sh/shdma-base.c |  2 +-
>  drivers/dma/sh/shdma.h      | 80 +++++++++++++++++++++++++++++++++++++
>  include/linux/shdma-base.h  | 80 +------------------------------------
>  3 files changed, 83 insertions(+), 79 deletions(-)

-- 
~Randy