[U-Boot] [PATCH v3] arm, i2c: added support for the TWSI I2C Interface
Heiko Schocher
hs at denx.de
Mon Jul 20 09:59:37 CEST 2009
Signed-off-by: Heiko Schocher <hs at denx.de>
---
- changes since v1:
added comments from Prafulla Wadaskar
- changes since v2
added comments from Jean-Christophe
- added speed setting
drivers/i2c/Makefile | 1 +
drivers/i2c/kirkwood_i2c.c | 484 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 485 insertions(+), 0 deletions(-)
create mode 100644 drivers/i2c/kirkwood_i2c.c
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index ef32f13..4a12976 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -28,6 +28,7 @@ LIB := $(obj)libi2c.a
COBJS-$(CONFIG_BFIN_TWI_I2C) += bfin-twi_i2c.o
COBJS-$(CONFIG_DRIVER_DAVINCI_I2C) += davinci_i2c.o
COBJS-$(CONFIG_FSL_I2C) += fsl_i2c.o
+COBJS-$(CONFIG_I2C_KIRKWOOD) += kirkwood_i2c.o
COBJS-$(CONFIG_I2C_MXC) += mxc_i2c.o
COBJS-$(CONFIG_DRIVER_OMAP1510_I2C) += omap1510_i2c.o
COBJS-$(CONFIG_DRIVER_OMAP24XX_I2C) += omap24xx_i2c.o
diff --git a/drivers/i2c/kirkwood_i2c.c b/drivers/i2c/kirkwood_i2c.c
new file mode 100644
index 0000000..dd30499
--- /dev/null
+++ b/drivers/i2c/kirkwood_i2c.c
@@ -0,0 +1,484 @@
+/*
+ * Driver for the i2c controller on the Marvell line of host bridges
+ * (e.g, gt642[46]0, mv643[46]0, mv644[46]0, Orion SoC family),
+ * and Kirkwood family.
+ *
+ * Based on:
+ * Author: Mark A. Greer <mgreer at mvista.com>
+ *
+ * 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.
+ *
+ * ported from Linux to u-boot
+ * (C) Copyright 2009
+ * Heiko Schocher, DENX Software Engineering, hs at denx.de.
+ *
+ */
+#include <common.h>
+#include <i2c.h>
+#include <asm/arch/kirkwood.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static unsigned int i2c_bus_num __attribute__ ((section (".data"))) = 0;
+#if defined(CONFIG_I2C_MUX)
+static unsigned int i2c_bus_num_mux __attribute__ ((section ("data"))) = 0;
+#endif
+
+/* Register defines */
+#define KW_I2C_REG_SLAVE_ADDR 0x00
+#define KW_I2C_REG_DATA 0x04
+#define KW_I2C_REG_CONTROL 0x08
+#define KW_I2C_REG_STATUS 0x0c
+#define KW_I2C_REG_BAUD 0x0c
+#define KW_I2C_REG_EXT_SLAVE_ADDR 0x10
+#define KW_I2C_REG_SOFT_RESET 0x1c
+
+#define KW_I2C_REG_CONTROL_ACK 0x00000004
+#define KW_I2C_REG_CONTROL_IFLG 0x00000008
+#define KW_I2C_REG_CONTROL_STOP 0x00000010
+#define KW_I2C_REG_CONTROL_START 0x00000020
+#define KW_I2C_REG_CONTROL_TWSIEN 0x00000040
+#define KW_I2C_REG_CONTROL_INTEN 0x00000080
+
+/* Ctlr status values */
+#define KW_I2C_STATUS_BUS_ERR 0x00
+#define KW_I2C_STATUS_MAST_START 0x08
+#define KW_I2C_STATUS_MAST_REPEAT_START 0x10
+#define KW_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
+#define KW_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
+#define KW_I2C_STATUS_MAST_WR_ACK 0x28
+#define KW_I2C_STATUS_MAST_WR_NO_ACK 0x30
+#define KW_I2C_STATUS_MAST_LOST_ARB 0x38
+#define KW_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
+#define KW_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
+#define KW_I2C_STATUS_MAST_RD_DATA_ACK 0x50
+#define KW_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
+#define KW_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
+#define KW_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
+#define KW_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
+#define KW_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
+#define KW_I2C_STATUS_NO_STATUS 0xf8
+
+/* Driver states */
+enum {
+ KW_I2C_STATE_INVALID,
+ KW_I2C_STATE_IDLE,
+ KW_I2C_STATE_WAITING_FOR_START_COND,
+ KW_I2C_STATE_WAITING_FOR_ADDR_1_ACK,
+ KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK,
+ KW_I2C_STATE_WAITING_FOR_SLAVE_ACK,
+ KW_I2C_STATE_WAITING_FOR_SLAVE_DATA,
+};
+
+/* Driver actions */
+enum {
+ KW_I2C_ACTION_INVALID,
+ KW_I2C_ACTION_CONTINUE,
+ KW_I2C_ACTION_SEND_START,
+ KW_I2C_ACTION_SEND_ADDR_1,
+ KW_I2C_ACTION_SEND_ADDR_2,
+ KW_I2C_ACTION_SEND_DATA,
+ KW_I2C_ACTION_RCV_DATA,
+ KW_I2C_ACTION_RCV_DATA_STOP,
+ KW_I2C_ACTION_SEND_STOP,
+};
+
+/* defines to get compatible with Linux driver */
+#define IRQ_NONE 0x0
+#define IRQ_HANDLED 0x01
+
+#define I2C_M_TEN 0x01
+#define I2C_M_RD 0x02
+#define I2C_M_REV_DIR_ADDR 0x04;
+
+struct i2c_msg {
+ u32 addr;
+ u32 flags;
+ u8 *buf;
+ u32 len;
+};
+
+struct kirkwood_i2c_data {
+ int irq;
+ u32 state;
+ u32 action;
+ u32 aborting;
+ u32 cntl_bits;
+ void *reg_base;
+ u32 reg_base_p;
+ u32 reg_size;
+ u32 addr1;
+ u32 addr2;
+ u32 bytes_left;
+ u32 byte_posn;
+ u32 block;
+ int rc;
+ u32 freq_m;
+ u32 freq_n;
+ struct i2c_msg *msg;
+};
+
+static struct kirkwood_i2c_data __drv_data __attribute__ ((section (".data")));
+static struct kirkwood_i2c_data *drv_data = &__drv_data;
+static struct i2c_msg __i2c_msg __attribute__ ((section (".data")));
+static struct i2c_msg *kirkwood_i2c_msg = &__i2c_msg;
+
+/*
+ *****************************************************************************
+ *
+ * Finite State Machine & Interrupt Routines
+ *
+ *****************************************************************************
+ */
+
+static inline int abs(int n)
+{
+ if(n >= 0)
+ return n;
+ else
+ return n * -1;
+}
+
+static void kirkwood_calculate_speed(int speed)
+{
+ int calcspeed;
+ int diff;
+ int best_diff = CONFIG_SYS_TCLK;
+ int best_speed = 0;
+ int m, n;
+ int tmp[8] = {2, 4, 8, 16, 32, 64, 128, 256};
+
+ for (n = 0; n < 8; n++) {
+ for (m = 0; m < 16; m++) {
+ calcspeed = CONFIG_SYS_TCLK / (10 * (m + 1) * tmp[n]);
+ diff = abs((speed - calcspeed));
+ if ( diff < best_diff) {
+ best_diff = diff;
+ best_speed = calcspeed;
+ drv_data->freq_m = m;
+ drv_data->freq_n = n;
+ }
+ }
+ }
+}
+
+/* Reset hardware and initialize FSM */
+static void
+kirkwood_i2c_hw_init(int speed, int slaveadd)
+{
+ drv_data->state = KW_I2C_STATE_IDLE;
+
+ kirkwood_calculate_speed(speed);
+ writel(0, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_SOFT_RESET);
+ writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)),
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_BAUD);
+ writel(slaveadd, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_SLAVE_ADDR);
+ writel(0, CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_EXT_SLAVE_ADDR);
+ writel(KW_I2C_REG_CONTROL_TWSIEN | KW_I2C_REG_CONTROL_STOP,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+}
+
+static void
+kirkwood_i2c_fsm(u32 status)
+{
+ /*
+ * If state is idle, then this is likely the remnants of an old
+ * operation that driver has given up on or the user has killed.
+ * If so, issue the stop condition and go to idle.
+ */
+ if (drv_data->state == KW_I2C_STATE_IDLE) {
+ drv_data->action = KW_I2C_ACTION_SEND_STOP;
+ return;
+ }
+
+ /* The status from the ctlr [mostly] tells us what to do next */
+ switch (status) {
+ /* Start condition interrupt */
+ case KW_I2C_STATUS_MAST_START: /* 0x08 */
+ case KW_I2C_STATUS_MAST_REPEAT_START: /* 0x10 */
+ drv_data->action = KW_I2C_ACTION_SEND_ADDR_1;
+ drv_data->state = KW_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
+ break;
+
+ /* Performing a write */
+ case KW_I2C_STATUS_MAST_WR_ADDR_ACK: /* 0x18 */
+ if (drv_data->msg->flags & I2C_M_TEN) {
+ drv_data->action = KW_I2C_ACTION_SEND_ADDR_2;
+ drv_data->state =
+ KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
+ break;
+ }
+ /* FALLTHRU */
+ case KW_I2C_STATUS_MAST_WR_ADDR_2_ACK: /* 0xd0 */
+ case KW_I2C_STATUS_MAST_WR_ACK: /* 0x28 */
+ if ((drv_data->bytes_left == 0)
+ || (drv_data->aborting
+ && (drv_data->byte_posn != 0))) {
+ drv_data->action = KW_I2C_ACTION_SEND_STOP;
+ drv_data->state = KW_I2C_STATE_IDLE;
+ } else {
+ drv_data->action = KW_I2C_ACTION_SEND_DATA;
+ drv_data->state =
+ KW_I2C_STATE_WAITING_FOR_SLAVE_ACK;
+ drv_data->bytes_left--;
+ }
+ break;
+
+ /* Performing a read */
+ case KW_I2C_STATUS_MAST_RD_ADDR_ACK: /* 40 */
+ if (drv_data->msg->flags & I2C_M_TEN) {
+ drv_data->action = KW_I2C_ACTION_SEND_ADDR_2;
+ drv_data->state =
+ KW_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
+ break;
+ }
+ /* FALLTHRU */
+ case KW_I2C_STATUS_MAST_RD_ADDR_2_ACK: /* 0xe0 */
+ if (drv_data->bytes_left == 0) {
+ drv_data->action = KW_I2C_ACTION_SEND_STOP;
+ drv_data->state = KW_I2C_STATE_IDLE;
+ break;
+ }
+ /* FALLTHRU */
+ case KW_I2C_STATUS_MAST_RD_DATA_ACK: /* 0x50 */
+ if (status != KW_I2C_STATUS_MAST_RD_DATA_ACK)
+ drv_data->action = KW_I2C_ACTION_CONTINUE;
+ else {
+ drv_data->action = KW_I2C_ACTION_RCV_DATA;
+ drv_data->bytes_left--;
+ }
+ drv_data->state = KW_I2C_STATE_WAITING_FOR_SLAVE_DATA;
+
+ if ((drv_data->bytes_left == 1) || drv_data->aborting)
+ drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_ACK;
+ break;
+
+ case KW_I2C_STATUS_MAST_RD_DATA_NO_ACK: /* 0x58 */
+ drv_data->action = KW_I2C_ACTION_RCV_DATA_STOP;
+ drv_data->state = KW_I2C_STATE_IDLE;
+ break;
+
+ case KW_I2C_STATUS_MAST_WR_ADDR_NO_ACK: /* 0x20 */
+ case KW_I2C_STATUS_MAST_WR_NO_ACK: /* 30 */
+ case KW_I2C_STATUS_MAST_RD_ADDR_NO_ACK: /* 48 */
+ /* Doesn't seem to be a device at other end */
+ drv_data->action = KW_I2C_ACTION_SEND_STOP;
+ drv_data->state = KW_I2C_STATE_IDLE;
+ drv_data->rc = -ENODEV;
+ break;
+
+ default:
+ printf("kirkwood_i2c_fsm: Ctlr Error -- state: 0x%x, "
+ "status: 0x%x, addr: 0x%x, flags: 0x%x\n",
+ drv_data->state, status, drv_data->msg->addr,
+ drv_data->msg->flags);
+ drv_data->action = KW_I2C_ACTION_SEND_STOP;
+ kirkwood_i2c_hw_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
+ drv_data->rc = -EIO;
+ }
+}
+
+static void
+kirkwood_i2c_do_action(void)
+{
+ switch(drv_data->action) {
+ case KW_I2C_ACTION_CONTINUE:
+ writel(drv_data->cntl_bits,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_SEND_START:
+ writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_START,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_SEND_ADDR_1:
+ writel(drv_data->addr1,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
+ writel(drv_data->cntl_bits,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_SEND_ADDR_2:
+ writel(drv_data->addr2,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
+ writel(drv_data->cntl_bits,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_SEND_DATA:
+ writel(drv_data->msg->buf[drv_data->byte_posn++],
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
+ writel(drv_data->cntl_bits,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_RCV_DATA:
+ drv_data->msg->buf[drv_data->byte_posn++] =
+ readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
+ writel(drv_data->cntl_bits,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ break;
+
+ case KW_I2C_ACTION_RCV_DATA_STOP:
+ drv_data->msg->buf[drv_data->byte_posn++] =
+ readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_DATA);
+ drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_INTEN;
+ writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_STOP,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ drv_data->block = 0;
+ break;
+
+ case KW_I2C_ACTION_INVALID:
+ default:
+ printf("kirkwood_i2c_do_action: Invalid action: %d\n",
+ drv_data->action);
+ drv_data->rc = -EIO;
+ /* FALLTHRU */
+ case KW_I2C_ACTION_SEND_STOP:
+ drv_data->cntl_bits &= ~KW_I2C_REG_CONTROL_INTEN;
+ writel(drv_data->cntl_bits | KW_I2C_REG_CONTROL_STOP,
+ CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ drv_data->block = 0;
+ break;
+ }
+}
+
+static int
+kirkwood_i2c_intr(void)
+{
+ u32 status;
+ u32 ctrl;
+ int rc = IRQ_NONE;
+
+ ctrl = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ while ((ctrl & KW_I2C_REG_CONTROL_IFLG) &&
+ (drv_data->rc == 0)) {
+ status = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_STATUS);
+ kirkwood_i2c_fsm(status);
+ kirkwood_i2c_do_action();
+ rc = IRQ_HANDLED;
+ ctrl = readl(CONFIG_I2C_KW_REG_BASE + KW_I2C_REG_CONTROL);
+ udelay(1000);
+ }
+ return rc;
+}
+
+static void
+kirkwood_i2c_doio(struct i2c_msg *msg)
+{
+ int ret;
+
+ while ((drv_data->rc == 0) && (drv_data->state != KW_I2C_STATE_IDLE)) {
+ /* poll Status register */
+ ret = kirkwood_i2c_intr();
+ if (ret == IRQ_NONE)
+ udelay(10);
+ }
+}
+
+static void
+kirkwood_i2c_prepare_for_io(struct i2c_msg *msg)
+{
+ u32 dir = 0;
+
+ drv_data->msg = msg;
+ drv_data->byte_posn = 0;
+ drv_data->bytes_left = msg->len;
+ drv_data->aborting = 0;
+ drv_data->rc = 0;
+ /* in u-boot we use no IRQs */
+ drv_data->cntl_bits = KW_I2C_REG_CONTROL_ACK | KW_I2C_REG_CONTROL_TWSIEN;
+
+ if (msg->flags & I2C_M_RD)
+ dir = 1;
+ if (msg->flags & I2C_M_TEN) {
+ drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
+ drv_data->addr2 = (u32)msg->addr & 0xff;
+ } else {
+ drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir;
+ drv_data->addr2 = 0;
+ }
+ /* OK, no start it (from kirkwood_i2c_execute_msg())*/
+ drv_data->action = KW_I2C_ACTION_SEND_START;
+ drv_data->state = KW_I2C_STATE_WAITING_FOR_START_COND;
+ drv_data->block = 1;
+ kirkwood_i2c_do_action();
+}
+
+void
+i2c_init(int speed, int slaveadd)
+{
+ kirkwood_i2c_hw_init(speed, slaveadd);
+}
+
+int
+i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
+{
+ kirkwood_i2c_msg->buf = data;
+ kirkwood_i2c_msg->len = length;
+ kirkwood_i2c_msg->addr = dev;
+ kirkwood_i2c_msg->flags = I2C_M_RD;
+
+ kirkwood_i2c_prepare_for_io(kirkwood_i2c_msg);
+ kirkwood_i2c_doio(kirkwood_i2c_msg);
+ return drv_data->rc;
+}
+
+int
+i2c_write(u8 dev, uint addr, int alen, u8 *data, int length)
+{
+ kirkwood_i2c_msg->buf = data;
+ kirkwood_i2c_msg->len = length;
+ kirkwood_i2c_msg->addr = dev;
+ kirkwood_i2c_msg->flags = 0;
+
+ kirkwood_i2c_prepare_for_io(kirkwood_i2c_msg);
+ kirkwood_i2c_doio(kirkwood_i2c_msg);
+ return drv_data->rc;
+}
+
+int
+i2c_probe(uchar chip)
+{
+ return i2c_read(chip, 0, 0, NULL, 0);
+}
+
+int i2c_set_bus_num(unsigned int bus)
+{
+#if defined(CONFIG_I2C_MUX)
+ if (bus < CONFIG_SYS_MAX_I2C_BUS) {
+ i2c_bus_num = bus;
+ } else {
+ int ret;
+
+ ret = i2x_mux_select_mux(bus);
+ if (ret)
+ return ret;
+ i2c_bus_num = 0;
+ }
+ i2c_bus_num_mux = bus;
+#else
+ if (bus > 0) {
+ return -1;
+ }
+
+ i2c_bus_num = bus;
+#endif
+ return 0;
+}
+
+unsigned int i2c_get_bus_num(void)
+{
+#if defined(CONFIG_I2C_MUX)
+ return i2c_bus_num_mux;
+#else
+ return i2c_bus_num;
+#endif
+}
+
--
1.6.0.GIT
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
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