1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3 * Copyright (C) 2018 Exceet Electronics GmbH
4 * Copyright (C) 2018 Bootlin
5 *
6 * Author:
7 * Peter Pan <peterpandong@micron.com>
8 * Boris Brezillon <boris.brezillon@bootlin.com>
9 */
10
11 #ifndef __LINUX_SPI_MEM_H
12 #define __LINUX_SPI_MEM_H
13
14 #include <linux/spi/spi.h>
15
16 #define SPI_MEM_OP_CMD(__opcode, __buswidth) \
17 { \
18 .buswidth = __buswidth, \
19 .opcode = __opcode, \
20 }
21
22 #define SPI_MEM_OP_ADDR(__nbytes, __val, __buswidth) \
23 { \
24 .nbytes = __nbytes, \
25 .val = __val, \
26 .buswidth = __buswidth, \
27 }
28
29 #define SPI_MEM_OP_NO_ADDR { }
30
31 #define SPI_MEM_OP_DUMMY(__nbytes, __buswidth) \
32 { \
33 .nbytes = __nbytes, \
34 .buswidth = __buswidth, \
35 }
36
37 #define SPI_MEM_OP_NO_DUMMY { }
38
39 #define SPI_MEM_OP_DATA_IN(__nbytes, __buf, __buswidth) \
40 { \
41 .dir = SPI_MEM_DATA_IN, \
42 .nbytes = __nbytes, \
43 .buf.in = __buf, \
44 .buswidth = __buswidth, \
45 }
46
47 #define SPI_MEM_OP_DATA_OUT(__nbytes, __buf, __buswidth) \
48 { \
49 .dir = SPI_MEM_DATA_OUT, \
50 .nbytes = __nbytes, \
51 .buf.out = __buf, \
52 .buswidth = __buswidth, \
53 }
54
55 #define SPI_MEM_OP_NO_DATA { }
56
57 /**
58 * enum spi_mem_data_dir - describes the direction of a SPI memory data
59 * transfer from the controller perspective
60 * @SPI_MEM_DATA_IN: data coming from the SPI memory
61 * @SPI_MEM_DATA_OUT: data sent the SPI memory
62 */
63 enum spi_mem_data_dir {
64 SPI_MEM_DATA_IN,
65 SPI_MEM_DATA_OUT,
66 };
67
68 /**
69 * struct spi_mem_op - describes a SPI memory operation
70 * @cmd.buswidth: number of IO lines used to transmit the command
71 * @cmd.opcode: operation opcode
72 * @addr.nbytes: number of address bytes to send. Can be zero if the operation
73 * does not need to send an address
74 * @addr.buswidth: number of IO lines used to transmit the address cycles
75 * @addr.val: address value. This value is always sent MSB first on the bus.
76 * Note that only @addr.nbytes are taken into account in this
77 * address value, so users should make sure the value fits in the
78 * assigned number of bytes.
79 * @dummy.nbytes: number of dummy bytes to send after an opcode or address. Can
80 * be zero if the operation does not require dummy bytes
81 * @dummy.buswidth: number of IO lanes used to transmit the dummy bytes
82 * @data.buswidth: number of IO lanes used to send/receive the data
83 * @data.dir: direction of the transfer
84 * @data.nbytes: number of data bytes to send/receive. Can be zero if the
85 * operation does not involve transferring data
86 * @data.buf.in: input buffer (must be DMA-able)
87 * @data.buf.out: output buffer (must be DMA-able)
88 */
89 struct spi_mem_op {
90 struct {
91 u8 buswidth;
92 u8 opcode;
93 } cmd;
94
95 struct {
96 u8 nbytes;
97 u8 buswidth;
98 u64 val;
99 } addr;
100
101 struct {
102 u8 nbytes;
103 u8 buswidth;
104 } dummy;
105
106 struct {
107 u8 buswidth;
108 enum spi_mem_data_dir dir;
109 unsigned int nbytes;
110 union {
111 void *in;
112 const void *out;
113 } buf;
114 } data;
115 };
116
117 #define SPI_MEM_OP(__cmd, __addr, __dummy, __data) \
118 { \
119 .cmd = __cmd, \
120 .addr = __addr, \
121 .dummy = __dummy, \
122 .data = __data, \
123 }
124
125 /**
126 * struct spi_mem - describes a SPI memory device
127 * @spi: the underlying SPI device
128 * @drvpriv: spi_mem_driver private data
129 * @name: name of the SPI memory device
130 *
131 * Extra information that describe the SPI memory device and may be needed by
132 * the controller to properly handle this device should be placed here.
133 *
134 * One example would be the device size since some controller expose their SPI
135 * mem devices through a io-mapped region.
136 */
137 struct spi_mem {
138 struct spi_device *spi;
139 void *drvpriv;
140 const char *name;
141 };
142
143 /**
144 * struct spi_mem_set_drvdata() - attach driver private data to a SPI mem
145 * device
146 * @mem: memory device
147 * @data: data to attach to the memory device
148 */
spi_mem_set_drvdata(struct spi_mem * mem,void * data)149 static inline void spi_mem_set_drvdata(struct spi_mem *mem, void *data)
150 {
151 mem->drvpriv = data;
152 }
153
154 /**
155 * struct spi_mem_get_drvdata() - get driver private data attached to a SPI mem
156 * device
157 * @mem: memory device
158 *
159 * Return: the data attached to the mem device.
160 */
spi_mem_get_drvdata(struct spi_mem * mem)161 static inline void *spi_mem_get_drvdata(struct spi_mem *mem)
162 {
163 return mem->drvpriv;
164 }
165
166 /**
167 * struct spi_controller_mem_ops - SPI memory operations
168 * @adjust_op_size: shrink the data xfer of an operation to match controller's
169 * limitations (can be alignment of max RX/TX size
170 * limitations)
171 * @supports_op: check if an operation is supported by the controller
172 * @exec_op: execute a SPI memory operation
173 * @get_name: get a custom name for the SPI mem device from the controller.
174 * This might be needed if the controller driver has been ported
175 * to use the SPI mem layer and a custom name is used to keep
176 * mtdparts compatible.
177 * Note that if the implementation of this function allocates memory
178 * dynamically, then it should do so with devm_xxx(), as we don't
179 * have a ->free_name() function.
180 *
181 * This interface should be implemented by SPI controllers providing an
182 * high-level interface to execute SPI memory operation, which is usually the
183 * case for QSPI controllers.
184 */
185 struct spi_controller_mem_ops {
186 int (*adjust_op_size)(struct spi_mem *mem, struct spi_mem_op *op);
187 bool (*supports_op)(struct spi_mem *mem,
188 const struct spi_mem_op *op);
189 int (*exec_op)(struct spi_mem *mem,
190 const struct spi_mem_op *op);
191 const char *(*get_name)(struct spi_mem *mem);
192 };
193
194 /**
195 * struct spi_mem_driver - SPI memory driver
196 * @spidrv: inherit from a SPI driver
197 * @probe: probe a SPI memory. Usually where detection/initialization takes
198 * place
199 * @remove: remove a SPI memory
200 * @shutdown: take appropriate action when the system is shutdown
201 *
202 * This is just a thin wrapper around a spi_driver. The core takes care of
203 * allocating the spi_mem object and forwarding the probe/remove/shutdown
204 * request to the spi_mem_driver. The reason we use this wrapper is because
205 * we might have to stuff more information into the spi_mem struct to let
206 * SPI controllers know more about the SPI memory they interact with, and
207 * having this intermediate layer allows us to do that without adding more
208 * useless fields to the spi_device object.
209 */
210 struct spi_mem_driver {
211 struct spi_driver spidrv;
212 int (*probe)(struct spi_mem *mem);
213 int (*remove)(struct spi_mem *mem);
214 void (*shutdown)(struct spi_mem *mem);
215 };
216
217 #if IS_ENABLED(CONFIG_SPI_MEM)
218 int spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
219 const struct spi_mem_op *op,
220 struct sg_table *sg);
221
222 void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
223 const struct spi_mem_op *op,
224 struct sg_table *sg);
225 #else
226 static inline int
spi_controller_dma_map_mem_op_data(struct spi_controller * ctlr,const struct spi_mem_op * op,struct sg_table * sg)227 spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
228 const struct spi_mem_op *op,
229 struct sg_table *sg)
230 {
231 return -ENOTSUPP;
232 }
233
234 static inline void
spi_controller_dma_unmap_mem_op_data(struct spi_controller * ctlr,const struct spi_mem_op * op,struct sg_table * sg)235 spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
236 const struct spi_mem_op *op,
237 struct sg_table *sg)
238 {
239 }
240 #endif /* CONFIG_SPI_MEM */
241
242 int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op);
243
244 bool spi_mem_supports_op(struct spi_mem *mem,
245 const struct spi_mem_op *op);
246
247 int spi_mem_exec_op(struct spi_mem *mem,
248 const struct spi_mem_op *op);
249
250 const char *spi_mem_get_name(struct spi_mem *mem);
251
252 int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv,
253 struct module *owner);
254
255 void spi_mem_driver_unregister(struct spi_mem_driver *drv);
256
257 #define spi_mem_driver_register(__drv) \
258 spi_mem_driver_register_with_owner(__drv, THIS_MODULE)
259
260 #define module_spi_mem_driver(__drv) \
261 module_driver(__drv, spi_mem_driver_register, \
262 spi_mem_driver_unregister)
263
264 #endif /* __LINUX_SPI_MEM_H */
265
