xref: /linux/drivers/usb/musb/musb_dma.h (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * MUSB OTG driver DMA controller abstraction
3  *
4  * Copyright 2005 Mentor Graphics Corporation
5  * Copyright (C) 2005-2006 by Texas Instruments
6  * Copyright (C) 2006-2007 Nokia Corporation
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA
21  *
22  * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
25  * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
29  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  */
34 
35 #ifndef __MUSB_DMA_H__
36 #define __MUSB_DMA_H__
37 
38 struct musb_hw_ep;
39 
40 /*
41  * DMA Controller Abstraction
42  *
43  * DMA Controllers are abstracted to allow use of a variety of different
44  * implementations of DMA, as allowed by the Inventra USB cores.  On the
45  * host side, usbcore sets up the DMA mappings and flushes caches; on the
46  * peripheral side, the gadget controller driver does.  Responsibilities
47  * of a DMA controller driver include:
48  *
49  *  - Handling the details of moving multiple USB packets
50  *    in cooperation with the Inventra USB core, including especially
51  *    the correct RX side treatment of short packets and buffer-full
52  *    states (both of which terminate transfers).
53  *
54  *  - Knowing the correlation between dma channels and the
55  *    Inventra core's local endpoint resources and data direction.
56  *
57  *  - Maintaining a list of allocated/available channels.
58  *
59  *  - Updating channel status on interrupts,
60  *    whether shared with the Inventra core or separate.
61  */
62 
63 #define	DMA_ADDR_INVALID	(~(dma_addr_t)0)
64 
65 #ifdef CONFIG_MUSB_PIO_ONLY
66 #define	is_dma_capable()	(0)
67 #else
68 #define	is_dma_capable()	(1)
69 #endif
70 
71 #ifdef CONFIG_USB_UX500_DMA
72 #define musb_dma_ux500(musb)		(musb->io.quirks & MUSB_DMA_UX500)
73 #else
74 #define musb_dma_ux500(musb)		0
75 #endif
76 
77 #ifdef CONFIG_USB_TI_CPPI41_DMA
78 #define musb_dma_cppi41(musb)		(musb->io.quirks & MUSB_DMA_CPPI41)
79 #else
80 #define musb_dma_cppi41(musb)		0
81 #endif
82 
83 #ifdef CONFIG_USB_TI_CPPI_DMA
84 #define musb_dma_cppi(musb)		(musb->io.quirks & MUSB_DMA_CPPI)
85 #else
86 #define musb_dma_cppi(musb)		0
87 #endif
88 
89 #ifdef CONFIG_USB_TUSB_OMAP_DMA
90 #define tusb_dma_omap(musb)		(musb->io.quirks & MUSB_DMA_TUSB_OMAP)
91 #else
92 #define tusb_dma_omap(musb)		0
93 #endif
94 
95 #ifdef CONFIG_USB_INVENTRA_DMA
96 #define musb_dma_inventra(musb)		(musb->io.quirks & MUSB_DMA_INVENTRA)
97 #else
98 #define musb_dma_inventra(musb)		0
99 #endif
100 
101 #if defined(CONFIG_USB_TI_CPPI_DMA) || defined(CONFIG_USB_TI_CPPI41_DMA)
102 #define	is_cppi_enabled(musb)		\
103 	(musb_dma_cppi(musb) || musb_dma_cppi41(musb))
104 #else
105 #define	is_cppi_enabled(musb)	0
106 #endif
107 
108 /* Anomaly 05000456 - USB Receive Interrupt Is Not Generated in DMA Mode 1
109  *	Only allow DMA mode 1 to be used when the USB will actually generate the
110  *	interrupts we expect.
111  */
112 #ifdef CONFIG_BLACKFIN
113 # undef USE_MODE1
114 # if !ANOMALY_05000456
115 #  define USE_MODE1
116 # endif
117 #endif
118 
119 /*
120  * DMA channel status ... updated by the dma controller driver whenever that
121  * status changes, and protected by the overall controller spinlock.
122  */
123 enum dma_channel_status {
124 	/* unallocated */
125 	MUSB_DMA_STATUS_UNKNOWN,
126 	/* allocated ... but not busy, no errors */
127 	MUSB_DMA_STATUS_FREE,
128 	/* busy ... transactions are active */
129 	MUSB_DMA_STATUS_BUSY,
130 	/* transaction(s) aborted due to ... dma or memory bus error */
131 	MUSB_DMA_STATUS_BUS_ABORT,
132 	/* transaction(s) aborted due to ... core error or USB fault */
133 	MUSB_DMA_STATUS_CORE_ABORT
134 };
135 
136 struct dma_controller;
137 
138 /**
139  * struct dma_channel - A DMA channel.
140  * @private_data: channel-private data
141  * @max_len: the maximum number of bytes the channel can move in one
142  *	transaction (typically representing many USB maximum-sized packets)
143  * @actual_len: how many bytes have been transferred
144  * @status: current channel status (updated e.g. on interrupt)
145  * @desired_mode: true if mode 1 is desired; false if mode 0 is desired
146  *
147  * channels are associated with an endpoint for the duration of at least
148  * one usb transfer.
149  */
150 struct dma_channel {
151 	void			*private_data;
152 	/* FIXME not void* private_data, but a dma_controller * */
153 	size_t			max_len;
154 	size_t			actual_len;
155 	enum dma_channel_status	status;
156 	bool			desired_mode;
157 	bool			rx_packet_done;
158 };
159 
160 /*
161  * dma_channel_status - return status of dma channel
162  * @c: the channel
163  *
164  * Returns the software's view of the channel status.  If that status is BUSY
165  * then it's possible that the hardware has completed (or aborted) a transfer,
166  * so the driver needs to update that status.
167  */
168 static inline enum dma_channel_status
169 dma_channel_status(struct dma_channel *c)
170 {
171 	return (is_dma_capable() && c) ? c->status : MUSB_DMA_STATUS_UNKNOWN;
172 }
173 
174 /**
175  * struct dma_controller - A DMA Controller.
176  * @start: call this to start a DMA controller;
177  *	return 0 on success, else negative errno
178  * @stop: call this to stop a DMA controller
179  *	return 0 on success, else negative errno
180  * @channel_alloc: call this to allocate a DMA channel
181  * @channel_release: call this to release a DMA channel
182  * @channel_abort: call this to abort a pending DMA transaction,
183  *	returning it to FREE (but allocated) state
184  *
185  * Controllers manage dma channels.
186  */
187 struct dma_controller {
188 	struct dma_channel	*(*channel_alloc)(struct dma_controller *,
189 					struct musb_hw_ep *, u8 is_tx);
190 	void			(*channel_release)(struct dma_channel *);
191 	int			(*channel_program)(struct dma_channel *channel,
192 							u16 maxpacket, u8 mode,
193 							dma_addr_t dma_addr,
194 							u32 length);
195 	int			(*channel_abort)(struct dma_channel *);
196 	int			(*is_compatible)(struct dma_channel *channel,
197 							u16 maxpacket,
198 							void *buf, u32 length);
199 };
200 
201 /* called after channel_program(), may indicate a fault */
202 extern void musb_dma_completion(struct musb *musb, u8 epnum, u8 transmit);
203 
204 #ifdef CONFIG_MUSB_PIO_ONLY
205 static inline struct dma_controller *
206 musb_dma_controller_create(struct musb *m, void __iomem *io)
207 {
208 	return NULL;
209 }
210 
211 static inline void musb_dma_controller_destroy(struct dma_controller *d) { }
212 
213 #else
214 
215 extern struct dma_controller *
216 (*musb_dma_controller_create)(struct musb *, void __iomem *);
217 
218 extern void (*musb_dma_controller_destroy)(struct dma_controller *);
219 #endif
220 
221 /* Platform specific DMA functions */
222 extern struct dma_controller *
223 musbhs_dma_controller_create(struct musb *musb, void __iomem *base);
224 extern void musbhs_dma_controller_destroy(struct dma_controller *c);
225 
226 extern struct dma_controller *
227 tusb_dma_controller_create(struct musb *musb, void __iomem *base);
228 extern void tusb_dma_controller_destroy(struct dma_controller *c);
229 
230 extern struct dma_controller *
231 cppi_dma_controller_create(struct musb *musb, void __iomem *base);
232 extern void cppi_dma_controller_destroy(struct dma_controller *c);
233 
234 extern struct dma_controller *
235 cppi41_dma_controller_create(struct musb *musb, void __iomem *base);
236 extern void cppi41_dma_controller_destroy(struct dma_controller *c);
237 
238 extern struct dma_controller *
239 ux500_dma_controller_create(struct musb *musb, void __iomem *base);
240 extern void ux500_dma_controller_destroy(struct dma_controller *c);
241 
242 #endif	/* __MUSB_DMA_H__ */
243