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Diffstat (limited to 'kernel/arch/powerpc/boot/mv64x60_i2c.c')
-rw-r--r--kernel/arch/powerpc/boot/mv64x60_i2c.c204
1 files changed, 204 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/boot/mv64x60_i2c.c b/kernel/arch/powerpc/boot/mv64x60_i2c.c
new file mode 100644
index 000000000..52a3212b6
--- /dev/null
+++ b/kernel/arch/powerpc/boot/mv64x60_i2c.c
@@ -0,0 +1,204 @@
+/*
+ * Bootloader version of the i2c driver for the MV64x60.
+ *
+ * Author: Dale Farnsworth <dfarnsworth@mvista.com>
+ * Maintained by: Mark A. Greer <mgreer@mvista.com>
+ *
+ * 2003, 2007 (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.
+ */
+
+#include <stdarg.h>
+#include <stddef.h>
+#include "types.h"
+#include "elf.h"
+#include "page.h"
+#include "string.h"
+#include "stdio.h"
+#include "io.h"
+#include "ops.h"
+#include "mv64x60.h"
+
+/* Register defines */
+#define MV64x60_I2C_REG_SLAVE_ADDR 0x00
+#define MV64x60_I2C_REG_DATA 0x04
+#define MV64x60_I2C_REG_CONTROL 0x08
+#define MV64x60_I2C_REG_STATUS 0x0c
+#define MV64x60_I2C_REG_BAUD 0x0c
+#define MV64x60_I2C_REG_EXT_SLAVE_ADDR 0x10
+#define MV64x60_I2C_REG_SOFT_RESET 0x1c
+
+#define MV64x60_I2C_CONTROL_ACK 0x04
+#define MV64x60_I2C_CONTROL_IFLG 0x08
+#define MV64x60_I2C_CONTROL_STOP 0x10
+#define MV64x60_I2C_CONTROL_START 0x20
+#define MV64x60_I2C_CONTROL_TWSIEN 0x40
+#define MV64x60_I2C_CONTROL_INTEN 0x80
+
+#define MV64x60_I2C_STATUS_BUS_ERR 0x00
+#define MV64x60_I2C_STATUS_MAST_START 0x08
+#define MV64x60_I2C_STATUS_MAST_REPEAT_START 0x10
+#define MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
+#define MV64x60_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
+#define MV64x60_I2C_STATUS_MAST_WR_ACK 0x28
+#define MV64x60_I2C_STATUS_MAST_WR_NO_ACK 0x30
+#define MV64x60_I2C_STATUS_MAST_LOST_ARB 0x38
+#define MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
+#define MV64x60_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
+#define MV64x60_I2C_STATUS_MAST_RD_DATA_ACK 0x50
+#define MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
+#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
+#define MV64x60_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
+#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
+#define MV64x60_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
+#define MV64x60_I2C_STATUS_NO_STATUS 0xf8
+
+static u8 *ctlr_base;
+
+static int mv64x60_i2c_wait_for_status(int wanted)
+{
+ int i;
+ int status;
+
+ for (i=0; i<1000; i++) {
+ udelay(10);
+ status = in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_STATUS))
+ & 0xff;
+ if (status == wanted)
+ return status;
+ }
+ return -status;
+}
+
+static int mv64x60_i2c_control(int control, int status)
+{
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+ return mv64x60_i2c_wait_for_status(status);
+}
+
+static int mv64x60_i2c_read_byte(int control, int status)
+{
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+ if (mv64x60_i2c_wait_for_status(status) < 0)
+ return -1;
+ return in_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA)) & 0xff;
+}
+
+static int mv64x60_i2c_write_byte(int data, int control, int status)
+{
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_DATA), data & 0xff);
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_CONTROL), control & 0xff);
+ return mv64x60_i2c_wait_for_status(status);
+}
+
+int mv64x60_i2c_read(u32 devaddr, u8 *buf, u32 offset, u32 offset_size,
+ u32 count)
+{
+ int i;
+ int data;
+ int control;
+ int status;
+
+ if (ctlr_base == NULL)
+ return -1;
+
+ /* send reset */
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SOFT_RESET), 0);
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_SLAVE_ADDR), 0);
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_EXT_SLAVE_ADDR), 0);
+ out_le32((u32 *)(ctlr_base + MV64x60_I2C_REG_BAUD), (4 << 3) | 0x4);
+
+ if (mv64x60_i2c_control(MV64x60_I2C_CONTROL_TWSIEN,
+ MV64x60_I2C_STATUS_NO_STATUS) < 0)
+ return -1;
+
+ /* send start */
+ control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_START;
+ if (mv64x60_i2c_control(control, status) < 0)
+ return -1;
+
+ /* select device for writing */
+ data = devaddr & ~0x1;
+ control = MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_WR_ADDR_ACK;
+ if (mv64x60_i2c_write_byte(data, control, status) < 0)
+ return -1;
+
+ /* send offset of data */
+ control = MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_WR_ACK;
+ if (offset_size > 1) {
+ if (mv64x60_i2c_write_byte(offset >> 8, control, status) < 0)
+ return -1;
+ }
+ if (mv64x60_i2c_write_byte(offset, control, status) < 0)
+ return -1;
+
+ /* resend start */
+ control = MV64x60_I2C_CONTROL_START | MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_REPEAT_START;
+ if (mv64x60_i2c_control(control, status) < 0)
+ return -1;
+
+ /* select device for reading */
+ data = devaddr | 0x1;
+ control = MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_RD_ADDR_ACK;
+ if (mv64x60_i2c_write_byte(data, control, status) < 0)
+ return -1;
+
+ /* read all but last byte of data */
+ control = MV64x60_I2C_CONTROL_ACK | MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_RD_DATA_ACK;
+
+ for (i=1; i<count; i++) {
+ data = mv64x60_i2c_read_byte(control, status);
+ if (data < 0) {
+ printf("errors on iteration %d\n", i);
+ return -1;
+ }
+ *buf++ = data;
+ }
+
+ /* read last byte of data */
+ control = MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_MAST_RD_DATA_NO_ACK;
+ data = mv64x60_i2c_read_byte(control, status);
+ if (data < 0)
+ return -1;
+ *buf++ = data;
+
+ /* send stop */
+ control = MV64x60_I2C_CONTROL_STOP | MV64x60_I2C_CONTROL_TWSIEN;
+ status = MV64x60_I2C_STATUS_NO_STATUS;
+ if (mv64x60_i2c_control(control, status) < 0)
+ return -1;
+
+ return count;
+}
+
+int mv64x60_i2c_open(void)
+{
+ u32 v;
+ void *devp;
+
+ devp = find_node_by_compatible(NULL, "marvell,mv64360-i2c");
+ if (devp == NULL)
+ goto err_out;
+ if (getprop(devp, "virtual-reg", &v, sizeof(v)) != sizeof(v))
+ goto err_out;
+
+ ctlr_base = (u8 *)v;
+ return 0;
+
+err_out:
+ return -1;
+}
+
+void mv64x60_i2c_close(void)
+{
+ ctlr_base = NULL;
+}