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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /sound/soc/codecs/rt5677-spi.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'sound/soc/codecs/rt5677-spi.c')
-rw-r--r--sound/soc/codecs/rt5677-spi.c237
1 files changed, 237 insertions, 0 deletions
diff --git a/sound/soc/codecs/rt5677-spi.c b/sound/soc/codecs/rt5677-spi.c
new file mode 100644
index 000000000..06abcd017
--- /dev/null
+++ b/sound/soc/codecs/rt5677-spi.c
@@ -0,0 +1,237 @@
+/*
+ * rt5677-spi.c -- RT5677 ALSA SoC audio codec driver
+ *
+ * Copyright 2013 Realtek Semiconductor Corp.
+ * Author: Oder Chiou <oder_chiou@realtek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/spi/spi.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_qos.h>
+#include <linux/sysfs.h>
+#include <linux/clk.h>
+#include <linux/firmware.h>
+
+#include "rt5677-spi.h"
+
+#define RT5677_SPI_BURST_LEN 240
+#define RT5677_SPI_HEADER 5
+#define RT5677_SPI_FREQ 6000000
+
+/* The AddressPhase and DataPhase of SPI commands are MSB first on the wire.
+ * DataPhase word size of 16-bit commands is 2 bytes.
+ * DataPhase word size of 32-bit commands is 4 bytes.
+ * DataPhase word size of burst commands is 8 bytes.
+ * The DSP CPU is little-endian.
+ */
+#define RT5677_SPI_WRITE_BURST 0x5
+#define RT5677_SPI_READ_BURST 0x4
+#define RT5677_SPI_WRITE_32 0x3
+#define RT5677_SPI_READ_32 0x2
+#define RT5677_SPI_WRITE_16 0x1
+#define RT5677_SPI_READ_16 0x0
+
+static struct spi_device *g_spi;
+static DEFINE_MUTEX(spi_mutex);
+
+/* Select a suitable transfer command for the next transfer to ensure
+ * the transfer address is always naturally aligned while minimizing
+ * the total number of transfers required.
+ *
+ * 3 transfer commands are available:
+ * RT5677_SPI_READ/WRITE_16: Transfer 2 bytes
+ * RT5677_SPI_READ/WRITE_32: Transfer 4 bytes
+ * RT5677_SPI_READ/WRITE_BURST: Transfer any multiples of 8 bytes
+ *
+ * Note:
+ * 16 Bit writes and reads are restricted to the address range
+ * 0x18020000 ~ 0x18021000
+ *
+ * For example, reading 256 bytes at 0x60030004 uses the following commands:
+ * 0x60030004 RT5677_SPI_READ_32 4 bytes
+ * 0x60030008 RT5677_SPI_READ_BURST 240 bytes
+ * 0x600300F8 RT5677_SPI_READ_BURST 8 bytes
+ * 0x60030100 RT5677_SPI_READ_32 4 bytes
+ *
+ * Input:
+ * @read: true for read commands; false for write commands
+ * @align: alignment of the next transfer address
+ * @remain: number of bytes remaining to transfer
+ *
+ * Output:
+ * @len: number of bytes to transfer with the selected command
+ * Returns the selected command
+ */
+static u8 rt5677_spi_select_cmd(bool read, u32 align, u32 remain, u32 *len)
+{
+ u8 cmd;
+
+ if (align == 4 || remain <= 4) {
+ cmd = RT5677_SPI_READ_32;
+ *len = 4;
+ } else {
+ cmd = RT5677_SPI_READ_BURST;
+ *len = (((remain - 1) >> 3) + 1) << 3;
+ *len = min_t(u32, *len, RT5677_SPI_BURST_LEN);
+ }
+ return read ? cmd : cmd + 1;
+}
+
+/* Copy dstlen bytes from src to dst, while reversing byte order for each word.
+ * If srclen < dstlen, zeros are padded.
+ */
+static void rt5677_spi_reverse(u8 *dst, u32 dstlen, const u8 *src, u32 srclen)
+{
+ u32 w, i, si;
+ u32 word_size = min_t(u32, dstlen, 8);
+
+ for (w = 0; w < dstlen; w += word_size) {
+ for (i = 0; i < word_size; i++) {
+ si = w + word_size - i - 1;
+ dst[w + i] = si < srclen ? src[si] : 0;
+ }
+ }
+}
+
+/* Read DSP address space using SPI. addr and len have to be 4-byte aligned. */
+int rt5677_spi_read(u32 addr, void *rxbuf, size_t len)
+{
+ u32 offset;
+ int status = 0;
+ struct spi_transfer t[2];
+ struct spi_message m;
+ /* +4 bytes is for the DummyPhase following the AddressPhase */
+ u8 header[RT5677_SPI_HEADER + 4];
+ u8 body[RT5677_SPI_BURST_LEN];
+ u8 spi_cmd;
+ u8 *cb = rxbuf;
+
+ if (!g_spi)
+ return -ENODEV;
+
+ if ((addr & 3) || (len & 3)) {
+ dev_err(&g_spi->dev, "Bad read align 0x%x(%zu)\n", addr, len);
+ return -EACCES;
+ }
+
+ memset(t, 0, sizeof(t));
+ t[0].tx_buf = header;
+ t[0].len = sizeof(header);
+ t[0].speed_hz = RT5677_SPI_FREQ;
+ t[1].rx_buf = body;
+ t[1].speed_hz = RT5677_SPI_FREQ;
+ spi_message_init_with_transfers(&m, t, ARRAY_SIZE(t));
+
+ for (offset = 0; offset < len; offset += t[1].len) {
+ spi_cmd = rt5677_spi_select_cmd(true, (addr + offset) & 7,
+ len - offset, &t[1].len);
+
+ /* Construct SPI message header */
+ header[0] = spi_cmd;
+ header[1] = ((addr + offset) & 0xff000000) >> 24;
+ header[2] = ((addr + offset) & 0x00ff0000) >> 16;
+ header[3] = ((addr + offset) & 0x0000ff00) >> 8;
+ header[4] = ((addr + offset) & 0x000000ff) >> 0;
+
+ mutex_lock(&spi_mutex);
+ status |= spi_sync(g_spi, &m);
+ mutex_unlock(&spi_mutex);
+
+ /* Copy data back to caller buffer */
+ rt5677_spi_reverse(cb + offset, t[1].len, body, t[1].len);
+ }
+ return status;
+}
+EXPORT_SYMBOL_GPL(rt5677_spi_read);
+
+/* Write DSP address space using SPI. addr has to be 4-byte aligned.
+ * If len is not 4-byte aligned, then extra zeros are written at the end
+ * as padding.
+ */
+int rt5677_spi_write(u32 addr, const void *txbuf, size_t len)
+{
+ u32 offset;
+ int status = 0;
+ struct spi_transfer t;
+ struct spi_message m;
+ /* +1 byte is for the DummyPhase following the DataPhase */
+ u8 buf[RT5677_SPI_HEADER + RT5677_SPI_BURST_LEN + 1];
+ u8 *body = buf + RT5677_SPI_HEADER;
+ u8 spi_cmd;
+ const u8 *cb = txbuf;
+
+ if (!g_spi)
+ return -ENODEV;
+
+ if (addr & 3) {
+ dev_err(&g_spi->dev, "Bad write align 0x%x(%zu)\n", addr, len);
+ return -EACCES;
+ }
+
+ memset(&t, 0, sizeof(t));
+ t.tx_buf = buf;
+ t.speed_hz = RT5677_SPI_FREQ;
+ spi_message_init_with_transfers(&m, &t, 1);
+
+ for (offset = 0; offset < len;) {
+ spi_cmd = rt5677_spi_select_cmd(false, (addr + offset) & 7,
+ len - offset, &t.len);
+
+ /* Construct SPI message header */
+ buf[0] = spi_cmd;
+ buf[1] = ((addr + offset) & 0xff000000) >> 24;
+ buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
+ buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
+ buf[4] = ((addr + offset) & 0x000000ff) >> 0;
+
+ /* Fetch data from caller buffer */
+ rt5677_spi_reverse(body, t.len, cb + offset, len - offset);
+ offset += t.len;
+ t.len += RT5677_SPI_HEADER + 1;
+
+ mutex_lock(&spi_mutex);
+ status |= spi_sync(g_spi, &m);
+ mutex_unlock(&spi_mutex);
+ }
+ return status;
+}
+EXPORT_SYMBOL_GPL(rt5677_spi_write);
+
+int rt5677_spi_write_firmware(u32 addr, const struct firmware *fw)
+{
+ return rt5677_spi_write(addr, fw->data, fw->size);
+}
+EXPORT_SYMBOL_GPL(rt5677_spi_write_firmware);
+
+static int rt5677_spi_probe(struct spi_device *spi)
+{
+ g_spi = spi;
+ return 0;
+}
+
+static struct spi_driver rt5677_spi_driver = {
+ .driver = {
+ .name = "rt5677",
+ },
+ .probe = rt5677_spi_probe,
+};
+module_spi_driver(rt5677_spi_driver);
+
+MODULE_DESCRIPTION("ASoC RT5677 SPI driver");
+MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
+MODULE_LICENSE("GPL v2");