drivers/media/dvb-frontends/cxd2880/cxd2880_devio_spi.c

   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
  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
  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
 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 }