1 files changed, 99 insertions, 0 deletions
diff --git a/arch/mips/txx9/rbtx4938/spi_eeprom.c b/arch/mips/txx9/rbtx4938/spi_eeprom.c
new file mode 100644
index 0000000..a7ea8b0
--- /dev/null
+++ b/arch/mips/txx9/rbtx4938/spi_eeprom.c
@@ -0,0 +1,99 @@
+/*
+ * spi_eeprom.c
+ * Copyright (C) 2000-2001 Toshiba Corporation
+ *
+ * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
+ * terms of the GNU General Public License version 2. This program is
+ * licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ *
+ * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
+ */
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/eeprom.h>
+#include <asm/txx9/spi.h>
+
+#define AT250X0_PAGE_SIZE	8
+
+/* register board information for at25 driver */
+int __init spi_eeprom_register(int chipid)
+{
+	static struct spi_eeprom eeprom = {
+		.name = "at250x0",
+		.byte_len = 128,
+		.page_size = AT250X0_PAGE_SIZE,
+		.flags = EE_ADDR1,
+	};
+	struct spi_board_info info = {
+		.modalias = "at25",
+		.max_speed_hz = 1500000,	/* 1.5Mbps */
+		.bus_num = 0,
+		.chip_select = chipid,
+		.platform_data = &eeprom,
+		/* Mode 0: High-Active, Sample-Then-Shift */
+	};
+
+	return spi_register_board_info(&info, 1);
+}
+
+/* simple temporary spi driver to provide early access to seeprom. */
+
+static struct read_param {
+	int chipid;
+	int address;
+	unsigned char *buf;
+	int len;
+} *read_param;
+
+static int __init early_seeprom_probe(struct spi_device *spi)
+{
+	int stat = 0;
+	u8 cmd[2];
+	int len = read_param->len;
+	char *buf = read_param->buf;
+	int address = read_param->address;
+
+	dev_info(&spi->dev, "spiclk %u KHz.\n",
+		 (spi->max_speed_hz + 500) / 1000);
+	if (read_param->chipid != spi->chip_select)
+		return -ENODEV;
+	while (len > 0) {
+		/* spi_write_then_read can only work with small chunk */
+		int c = len < AT250X0_PAGE_SIZE ? len : AT250X0_PAGE_SIZE;
+		cmd[0] = 0x03;	/* AT25_READ */
+		cmd[1] = address;
+		stat = spi_write_then_read(spi, cmd, sizeof(cmd), buf, c);
+		buf += c;
+		len -= c;
+		address += c;
+	}
+	return stat;
+}
+
+static struct spi_driver early_seeprom_driver __initdata = {
+	.driver = {
+		.name	= "at25",
+		.owner	= THIS_MODULE,
+	},
+	.probe	= early_seeprom_probe,
+};
+
+int __init spi_eeprom_read(int chipid, int address,
+			   unsigned char *buf, int len)
+{
+	int ret;
+	struct read_param param = {
+		.chipid = chipid,
+		.address = address,
+		.buf = buf,
+		.len = len
+	};
+
+	read_param = &param;
+	ret = spi_register_driver(&early_seeprom_driver);
+	if (!ret)
+		spi_unregister_driver(&early_seeprom_driver);
+	return ret;
+}