xref: /linux/drivers/media/dvb-frontends/cxd2880/cxd2880_devio_spi.c (revision c13aca79ff3c4af5fd31a5b2743a90eba6e36a26)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * cxd2880_devio_spi.c
4  * Sony CXD2880 DVB-T2/T tuner + demodulator driver
5  * I/O interface via SPI
6  *
7  * Copyright (C) 2016, 2017, 2018 Sony Semiconductor Solutions Corporation
8  */
9 
10 #include "cxd2880_devio_spi.h"
11 
12 #define BURST_WRITE_MAX 128
13 
cxd2880_io_spi_read_reg(struct cxd2880_io * io,enum cxd2880_io_tgt tgt,u8 sub_address,u8 * data,u32 size)14 static int cxd2880_io_spi_read_reg(struct cxd2880_io *io,
15 				   enum cxd2880_io_tgt tgt,
16 				   u8 sub_address, u8 *data,
17 				   u32 size)
18 {
19 	int ret = 0;
20 	struct cxd2880_spi *spi = NULL;
21 	u8 send_data[6];
22 	u8 *read_data_top = data;
23 
24 	if (!io || !io->if_object || !data)
25 		return -EINVAL;
26 
27 	if (sub_address + size > 0x100)
28 		return -EINVAL;
29 
30 	spi = io->if_object;
31 
32 	if (tgt == CXD2880_IO_TGT_SYS)
33 		send_data[0] = 0x0b;
34 	else
35 		send_data[0] = 0x0a;
36 
37 	send_data[3] = 0;
38 	send_data[4] = 0;
39 	send_data[5] = 0;
40 
41 	while (size > 0) {
42 		send_data[1] = sub_address;
43 		if (size > 255)
44 			send_data[2] = 255;
45 		else
46 			send_data[2] = size;
47 
48 		ret =
49 		    spi->write_read(spi, send_data, sizeof(send_data),
50 				    read_data_top, send_data[2]);
51 		if (ret)
52 			return ret;
53 
54 		sub_address += send_data[2];
55 		read_data_top += send_data[2];
56 		size -= send_data[2];
57 	}
58 
59 	return ret;
60 }
61 
cxd2880_io_spi_write_reg(struct cxd2880_io * io,enum cxd2880_io_tgt tgt,u8 sub_address,const u8 * data,u32 size)62 static int cxd2880_io_spi_write_reg(struct cxd2880_io *io,
63 				    enum cxd2880_io_tgt tgt,
64 				    u8 sub_address,
65 				    const u8 *data, u32 size)
66 {
67 	int ret = 0;
68 	struct cxd2880_spi *spi = NULL;
69 	u8 send_data[BURST_WRITE_MAX + 4];
70 	const u8 *write_data_top = data;
71 
72 	if (!io || !io->if_object || !data)
73 		return -EINVAL;
74 
75 	if (size > BURST_WRITE_MAX)
76 		return -EINVAL;
77 
78 	if (sub_address + size > 0x100)
79 		return -EINVAL;
80 
81 	spi = io->if_object;
82 
83 	if (tgt == CXD2880_IO_TGT_SYS)
84 		send_data[0] = 0x0f;
85 	else
86 		send_data[0] = 0x0e;
87 
88 	while (size > 0) {
89 		send_data[1] = sub_address;
90 		if (size > 255)
91 			send_data[2] = 255;
92 		else
93 			send_data[2] = size;
94 
95 		memcpy(&send_data[3], write_data_top, send_data[2]);
96 
97 		if (tgt == CXD2880_IO_TGT_SYS) {
98 			send_data[3 + send_data[2]] = 0x00;
99 			ret = spi->write(spi, send_data, send_data[2] + 4);
100 		} else {
101 			ret = spi->write(spi, send_data, send_data[2] + 3);
102 		}
103 		if (ret)
104 			return ret;
105 
106 		sub_address += send_data[2];
107 		write_data_top += send_data[2];
108 		size -= send_data[2];
109 	}
110 
111 	return ret;
112 }
113 
cxd2880_io_spi_create(struct cxd2880_io * io,struct cxd2880_spi * spi,u8 slave_select)114 int cxd2880_io_spi_create(struct cxd2880_io *io,
115 			  struct cxd2880_spi *spi, u8 slave_select)
116 {
117 	if (!io || !spi)
118 		return -EINVAL;
119 
120 	io->read_regs = cxd2880_io_spi_read_reg;
121 	io->write_regs = cxd2880_io_spi_write_reg;
122 	io->write_reg = cxd2880_io_common_write_one_reg;
123 	io->if_object = spi;
124 	io->i2c_address_sys = 0;
125 	io->i2c_address_demod = 0;
126 	io->slave_select = slave_select;
127 
128 	return 0;
129 }
130