1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef __ASM_ARCH_DMA_H |
3 | #define __ASM_ARCH_DMA_H |
4 | |
5 | #include <linux/types.h> |
6 | #include <linux/dmaengine.h> |
7 | #include <linux/dma-mapping.h> |
8 | |
9 | /* |
10 | * M2P channels. |
11 | * |
12 | * Note that these values are also directly used for setting the PPALLOC |
13 | * register. |
14 | */ |
15 | #define EP93XX_DMA_I2S1 0 |
16 | #define EP93XX_DMA_I2S2 1 |
17 | #define EP93XX_DMA_AAC1 2 |
18 | #define EP93XX_DMA_AAC2 3 |
19 | #define EP93XX_DMA_AAC3 4 |
20 | #define EP93XX_DMA_I2S3 5 |
21 | #define EP93XX_DMA_UART1 6 |
22 | #define EP93XX_DMA_UART2 7 |
23 | #define EP93XX_DMA_UART3 8 |
24 | #define EP93XX_DMA_IRDA 9 |
25 | /* M2M channels */ |
26 | #define EP93XX_DMA_SSP 10 |
27 | #define EP93XX_DMA_IDE 11 |
28 | |
29 | /** |
30 | * struct ep93xx_dma_data - configuration data for the EP93xx dmaengine |
31 | * @port: peripheral which is requesting the channel |
32 | * @direction: TX/RX channel |
33 | * @name: optional name for the channel, this is displayed in /proc/interrupts |
34 | * |
35 | * This information is passed as private channel parameter in a filter |
36 | * function. Note that this is only needed for slave/cyclic channels. For |
37 | * memcpy channels %NULL data should be passed. |
38 | */ |
39 | struct ep93xx_dma_data { |
40 | int port; |
41 | enum dma_transfer_direction direction; |
42 | const char *name; |
43 | }; |
44 | |
45 | /** |
46 | * struct ep93xx_dma_chan_data - platform specific data for a DMA channel |
47 | * @name: name of the channel, used for getting the right clock for the channel |
48 | * @base: mapped registers |
49 | * @irq: interrupt number used by this channel |
50 | */ |
51 | struct ep93xx_dma_chan_data { |
52 | const char *name; |
53 | void __iomem *base; |
54 | int irq; |
55 | }; |
56 | |
57 | /** |
58 | * struct ep93xx_dma_platform_data - platform data for the dmaengine driver |
59 | * @channels: array of channels which are passed to the driver |
60 | * @num_channels: number of channels in the array |
61 | * |
62 | * This structure is passed to the DMA engine driver via platform data. For |
63 | * M2P channels, contract is that even channels are for TX and odd for RX. |
64 | * There is no requirement for the M2M channels. |
65 | */ |
66 | struct ep93xx_dma_platform_data { |
67 | struct ep93xx_dma_chan_data *channels; |
68 | size_t num_channels; |
69 | }; |
70 | |
71 | static inline bool ep93xx_dma_chan_is_m2p(struct dma_chan *chan) |
72 | { |
73 | return !strcmp(dev_name(dev: chan->device->dev), "ep93xx-dma-m2p" ); |
74 | } |
75 | |
76 | /** |
77 | * ep93xx_dma_chan_direction - returns direction the channel can be used |
78 | * @chan: channel |
79 | * |
80 | * This function can be used in filter functions to find out whether the |
81 | * channel supports given DMA direction. Only M2P channels have such |
82 | * limitation, for M2M channels the direction is configurable. |
83 | */ |
84 | static inline enum dma_transfer_direction |
85 | ep93xx_dma_chan_direction(struct dma_chan *chan) |
86 | { |
87 | if (!ep93xx_dma_chan_is_m2p(chan)) |
88 | return DMA_TRANS_NONE; |
89 | |
90 | /* even channels are for TX, odd for RX */ |
91 | return (chan->chan_id % 2 == 0) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM; |
92 | } |
93 | |
94 | #endif /* __ASM_ARCH_DMA_H */ |
95 | |