1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // tcan4x5x - Texas Instruments TCAN4x5x Family CAN controller driver
4 //
5 // Copyright (c) 2020 Pengutronix,
6 // Marc Kleine-Budde <kernel@pengutronix.de>
7 // Copyright (c) 2018-2019 Texas Instruments Incorporated
8 // http://www.ti.com/
9
10 #include "tcan4x5x.h"
11
12 #define TCAN4X5X_SPI_INSTRUCTION_WRITE (0x61 << 24)
13 #define TCAN4X5X_SPI_INSTRUCTION_READ (0x41 << 24)
14
15 #define TCAN4X5X_MAX_REGISTER 0x87fc
16
tcan4x5x_regmap_gather_write(void * context,const void * reg,size_t reg_len,const void * val,size_t val_len)17 static int tcan4x5x_regmap_gather_write(void *context,
18 const void *reg, size_t reg_len,
19 const void *val, size_t val_len)
20 {
21 struct spi_device *spi = context;
22 struct tcan4x5x_priv *priv = spi_get_drvdata(spi);
23 struct tcan4x5x_map_buf *buf_tx = &priv->map_buf_tx;
24 struct spi_transfer xfer[] = {
25 {
26 .tx_buf = buf_tx,
27 .len = sizeof(buf_tx->cmd) + val_len,
28 },
29 };
30
31 memcpy(&buf_tx->cmd, reg, sizeof(buf_tx->cmd.cmd) +
32 sizeof(buf_tx->cmd.addr));
33 tcan4x5x_spi_cmd_set_len(&buf_tx->cmd, val_len);
34 memcpy(buf_tx->data, val, val_len);
35
36 return spi_sync_transfer(spi, xfer, ARRAY_SIZE(xfer));
37 }
38
tcan4x5x_regmap_write(void * context,const void * data,size_t count)39 static int tcan4x5x_regmap_write(void *context, const void *data, size_t count)
40 {
41 return tcan4x5x_regmap_gather_write(context, data, sizeof(__be32),
42 data + sizeof(__be32),
43 count - sizeof(__be32));
44 }
45
tcan4x5x_regmap_read(void * context,const void * reg_buf,size_t reg_len,void * val_buf,size_t val_len)46 static int tcan4x5x_regmap_read(void *context,
47 const void *reg_buf, size_t reg_len,
48 void *val_buf, size_t val_len)
49 {
50 struct spi_device *spi = context;
51 struct tcan4x5x_priv *priv = spi_get_drvdata(spi);
52 struct tcan4x5x_map_buf *buf_rx = &priv->map_buf_rx;
53 struct tcan4x5x_map_buf *buf_tx = &priv->map_buf_tx;
54 struct spi_transfer xfer[2] = {
55 {
56 .tx_buf = buf_tx,
57 }
58 };
59 struct spi_message msg;
60 int err;
61
62 spi_message_init(&msg);
63 spi_message_add_tail(&xfer[0], &msg);
64
65 memcpy(&buf_tx->cmd, reg_buf, sizeof(buf_tx->cmd.cmd) +
66 sizeof(buf_tx->cmd.addr));
67 tcan4x5x_spi_cmd_set_len(&buf_tx->cmd, val_len);
68
69 if (spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX) {
70 xfer[0].len = sizeof(buf_tx->cmd);
71
72 xfer[1].rx_buf = val_buf;
73 xfer[1].len = val_len;
74 spi_message_add_tail(&xfer[1], &msg);
75 } else {
76 xfer[0].rx_buf = buf_rx;
77 xfer[0].len = sizeof(buf_tx->cmd) + val_len;
78
79 if (TCAN4X5X_SANITIZE_SPI)
80 memset(buf_tx->data, 0x0, val_len);
81 }
82
83 err = spi_sync(spi, &msg);
84 if (err)
85 return err;
86
87 if (!(spi->controller->flags & SPI_CONTROLLER_HALF_DUPLEX))
88 memcpy(val_buf, buf_rx->data, val_len);
89
90 return 0;
91 }
92
93 static const struct regmap_range tcan4x5x_reg_table_yes_range[] = {
94 regmap_reg_range(0x0000, 0x002c), /* Device ID and SPI Registers */
95 regmap_reg_range(0x0800, 0x083c), /* Device configuration registers and Interrupt Flags*/
96 regmap_reg_range(0x1000, 0x10fc), /* M_CAN */
97 regmap_reg_range(0x8000, 0x87fc), /* MRAM */
98 };
99
100 static const struct regmap_access_table tcan4x5x_reg_table = {
101 .yes_ranges = tcan4x5x_reg_table_yes_range,
102 .n_yes_ranges = ARRAY_SIZE(tcan4x5x_reg_table_yes_range),
103 };
104
105 static const struct regmap_config tcan4x5x_regmap = {
106 .reg_bits = 24,
107 .reg_stride = 4,
108 .pad_bits = 8,
109 .val_bits = 32,
110 .wr_table = &tcan4x5x_reg_table,
111 .rd_table = &tcan4x5x_reg_table,
112 .max_register = TCAN4X5X_MAX_REGISTER,
113 .cache_type = REGCACHE_NONE,
114 .read_flag_mask = (__force unsigned long)
115 cpu_to_be32(TCAN4X5X_SPI_INSTRUCTION_READ),
116 .write_flag_mask = (__force unsigned long)
117 cpu_to_be32(TCAN4X5X_SPI_INSTRUCTION_WRITE),
118 };
119
120 static const struct regmap_bus tcan4x5x_bus = {
121 .write = tcan4x5x_regmap_write,
122 .gather_write = tcan4x5x_regmap_gather_write,
123 .read = tcan4x5x_regmap_read,
124 .reg_format_endian_default = REGMAP_ENDIAN_BIG,
125 .val_format_endian_default = REGMAP_ENDIAN_BIG,
126 .max_raw_read = 256,
127 .max_raw_write = 256,
128 };
129
tcan4x5x_regmap_init(struct tcan4x5x_priv * priv)130 int tcan4x5x_regmap_init(struct tcan4x5x_priv *priv)
131 {
132 priv->regmap = devm_regmap_init(&priv->spi->dev, &tcan4x5x_bus,
133 priv->spi, &tcan4x5x_regmap);
134 return PTR_ERR_OR_ZERO(priv->regmap);
135 }
136