kernel/sound/soc/codecs/rt5677-spi.c

   1 /*
   2  * rt5677-spi.c  --  RT5677 ALSA SoC audio codec driver
   3  *
   4  * Copyright 2013 Realtek Semiconductor Corp.
   5  * Author: Oder Chiou <oder_chiou@realtek.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/input.h>
  14 #include <linux/spi/spi.h>
  15 #include <linux/device.h>
  16 #include <linux/init.h>
  17 #include <linux/delay.h>
  18 #include <linux/interrupt.h>
  19 #include <linux/irq.h>
  20 #include <linux/slab.h>
  21 #include <linux/gpio.h>
  22 #include <linux/sched.h>
  23 #include <linux/kthread.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/miscdevice.h>
  26 #include <linux/regulator/consumer.h>
  27 #include <linux/pm_qos.h>
  28 #include <linux/sysfs.h>
  29 #include <linux/clk.h>
  30 #include <linux/firmware.h>
  31
  32 #include "rt5677-spi.h"
  33
  34 static struct spi_device *g_spi;
  35
  36 /**
  37  * rt5677_spi_write - Write data to SPI.
  38  * @txbuf: Data Buffer for writing.
  39  * @len: Data length.
  40  *
  41  *
  42  * Returns true for success.
  43  */
  44 int rt5677_spi_write(u8 *txbuf, size_t len)
  45 {
  46         int status;
  47
  48         status = spi_write(g_spi, txbuf, len);
  49
  50         if (status)
  51                 dev_err(&g_spi->dev, "rt5677_spi_write error %d\n", status);
  52
  53         return status;
  54 }
  55 EXPORT_SYMBOL_GPL(rt5677_spi_write);
  56
  57 /**
  58  * rt5677_spi_burst_write - Write data to SPI by rt5677 dsp memory address.
  59  * @addr: Start address.
  60  * @txbuf: Data Buffer for writng.
  61  * @len: Data length, it must be a multiple of 8.
  62  *
  63  *
  64  * Returns true for success.
  65  */
  66 int rt5677_spi_burst_write(u32 addr, const struct firmware *fw)
  67 {
  68         u8 spi_cmd = RT5677_SPI_CMD_BURST_WRITE;
  69         u8 *write_buf;
  70         unsigned int i, end, offset = 0;
  71
  72         write_buf = kmalloc(RT5677_SPI_BUF_LEN + 6, GFP_KERNEL);
  73
  74         if (write_buf == NULL)
  75                 return -ENOMEM;
  76
  77         while (offset < fw->size) {
  78                 if (offset + RT5677_SPI_BUF_LEN <= fw->size)
  79                         end = RT5677_SPI_BUF_LEN;
  80                 else
  81                         end = fw->size % RT5677_SPI_BUF_LEN;
  82
  83                 write_buf[0] = spi_cmd;
  84                 write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
  85                 write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
  86                 write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
  87                 write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
  88
  89                 for (i = 0; i < end; i += 8) {
  90                         write_buf[i + 12] = fw->data[offset + i + 0];
  91                         write_buf[i + 11] = fw->data[offset + i + 1];
  92                         write_buf[i + 10] = fw->data[offset + i + 2];
  93                         write_buf[i +  9] = fw->data[offset + i + 3];
  94                         write_buf[i +  8] = fw->data[offset + i + 4];
  95                         write_buf[i +  7] = fw->data[offset + i + 5];
  96                         write_buf[i +  6] = fw->data[offset + i + 6];
  97                         write_buf[i +  5] = fw->data[offset + i + 7];
  98                 }
  99
 100                 write_buf[end + 5] = spi_cmd;
 101
 102                 rt5677_spi_write(write_buf, end + 6);
 103
 104                 offset += RT5677_SPI_BUF_LEN;
 105         }
 106
 107         kfree(write_buf);
 108
 109         return 0;
 110 }
 111 EXPORT_SYMBOL_GPL(rt5677_spi_burst_write);
 112
 113 static int rt5677_spi_probe(struct spi_device *spi)
 114 {
 115         g_spi = spi;
 116         return 0;
 117 }
 118
 119 static struct spi_driver rt5677_spi_driver = {
 120         .driver = {
 121                 .name = "rt5677",
 122                 .owner = THIS_MODULE,
 123         },
 124         .probe = rt5677_spi_probe,
 125 };
 126 module_spi_driver(rt5677_spi_driver);
 127
 128 MODULE_DESCRIPTION("ASoC RT5677 SPI driver");
 129 MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
 130 MODULE_LICENSE("GPL v2");