[U-Boot] [PATCH v2 6/9] i2c driver support for SPEAr SoCs

Vipin KUMAR
2010-01-07T11:56:27Z

Signed-off-by: Vipin <vipin.kumar@st.com>
---
drivers/i2c/Makefile | 1 +
drivers/i2c/spr_i2c.c | 340 ++++++++++++++++++++++++++++++++++
include/asm-arm/arch-spear/spr_i2c.h | 146 +++++++++++++++
include/configs/spear.h | 2 +-
4 files changed, 488 insertions(+), 1 deletions(-)
mode change 100644 => 100755 drivers/i2c/Makefile
create mode 100755 drivers/i2c/spr_i2c.c
create mode 100755 include/asm-arm/arch-spear/spr_i2c.h

diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
old mode 100644
new mode 100755
index b860e89..29bda85
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -37,6 +37,7 @@ COBJS-$(CONFIG_PCA9564_I2C) += pca9564_i2c.o
COBJS-$(CONFIG_DRIVER_S3C24X0_I2C) += s3c24x0_i2c.o
COBJS-$(CONFIG_S3C44B0_I2C) += s3c44b0_i2c.o
COBJS-$(CONFIG_SOFT_I2C) += soft_i2c.o
+COBJS-$(CONFIG_SPEAR_I2C) += spr_i2c.o
COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o

COBJS := $(COBJS-y)
diff --git a/drivers/i2c/spr_i2c.c b/drivers/i2c/spr_i2c.c
new file mode 100755
index 0000000..497ca47
--- /dev/null
+++ b/drivers/i2c/spr_i2c.c
@@ -0,0 +1,340 @@
+/*
+ * (C) Copyright 2009
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar at st.com.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/spr_i2c.h>
+
+static struct i2c_regs *const i2c_regs_p =
+ (struct i2c_regs *)CONFIG_SYS_I2C_BASE;
+
+/*
+ * set_speed - Set the i2c speed mode (standard, high, fast)
+ * @i2c_spd: required i2c speed mode
+ *
+ * Set the i2c speed mode (standard, high, fast)
+ */
+static void set_speed(int i2c_spd)
+{
+ unsigned int cntl;
+ unsigned int hcnt, lcnt;
+ unsigned int high, low;
+
+ cntl = (readl(&i2c_regs_p->ic_con) & (~IC_CON_SPD_MSK));
+
+ switch (i2c_spd) {
+ case IC_SPEED_MODE_MAX:
+ cntl |= IC_CON_SPD_HS;
+ high = MIN_HS_SCL_HIGHTIME;
+ low = MIN_HS_SCL_LOWTIME;
+ break;
+
+ case IC_SPEED_MODE_STANDARD:
+ cntl |= IC_CON_SPD_SS;
+ high = MIN_SS_SCL_HIGHTIME;
+ low = MIN_SS_SCL_LOWTIME;
+ break;
+
+ case IC_SPEED_MODE_FAST:
+ default:
+ cntl |= IC_CON_SPD_FS;
+ high = MIN_FS_SCL_HIGHTIME;
+ low = MIN_FS_SCL_LOWTIME;
+ break;
+ }
+
+ writel(cntl, &i2c_regs_p->ic_con);
+
+ hcnt = (IC_CLK * high) / NANO_TO_MICRO;
+ writel(hcnt, &i2c_regs_p->ic_fs_scl_hcnt);
+
+ lcnt = (IC_CLK * low) / NANO_TO_MICRO;
+ writel(lcnt, &i2c_regs_p->ic_fs_scl_lcnt);
+}
+
+/*
+ * i2c_set_bus_speed - Set the i2c speed
+ * @speed: required i2c speed
+ *
+ * Set the i2c speed.
+ */
+void i2c_set_bus_speed(int speed)
+{
+ if (speed >= I2C_MAX_SPEED) {
+ set_speed(IC_SPEED_MODE_MAX);
+
+ } else if (speed >= I2C_FAST_SPEED) {
+ set_speed(IC_SPEED_MODE_FAST);
+
+ } else {
+ set_speed(IC_SPEED_MODE_STANDARD);
+ }
+}
+
+/*
+ * i2c_get_bus_speed - Gets the i2c speed
+ *
+ * Gets the i2c speed.
+ */
+int i2c_get_bus_speed(void)
+{
+ u32 cntl;
+
+ cntl = (readl(&i2c_regs_p->ic_con) & IC_CON_SPD_MSK);
+
+ if (cntl == IC_CON_SPD_HS) {
+ return I2C_MAX_SPEED;
+
+ } else if (cntl == IC_CON_SPD_FS) {
+ return I2C_FAST_SPEED;
+
+ } else if (cntl == IC_CON_SPD_SS) {
+ return I2C_STANDARD_SPEED;
+ }
+
+ return 0;
+}
+
+/*
+ * i2c_init - Init function
+ * @speed: required i2c speed
+ * @slaveadd: slave address for the spear device
+ *
+ * Initialization function.
+ */
+void i2c_init(int speed, int slaveadd)
+{
+ unsigned int enbl;
+
+ /* Disable i2c */
+ enbl = readl(&i2c_regs_p->ic_enable);
+ enbl &= ~IC_ENABLE_0B;
+ writel(enbl, &i2c_regs_p->ic_enable);
+
+ writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_regs_p->ic_con);
+ writel(IC_RX_TL, &i2c_regs_p->ic_rx_tl);
+ writel(IC_TX_TL, &i2c_regs_p->ic_tx_tl);
+ i2c_set_bus_speed(speed);
+ writel(IC_STOP_DET, &i2c_regs_p->ic_intr_mask);
+ writel(slaveadd, &i2c_regs_p->ic_sar);
+
+ /* Enable i2c */
+ enbl = readl(&i2c_regs_p->ic_enable);
+ enbl |= IC_ENABLE_0B;
+ writel(enbl, &i2c_regs_p->ic_enable);
+}
+
+/*
+ * i2c_setaddress - Sets the target slave address
+ * @i2c_addr: target i2c address
+ *
+ * Sets the target slave address.
+ */
+static void i2c_setaddress(unsigned int i2c_addr)
+{
+ writel(i2c_addr, &i2c_regs_p->ic_tar);
+}
+
+/*
+ * i2c_flush_rxfifo - Flushes the i2c RX FIFO
+ *
+ * Flushes the i2c RX FIFO
+ */
+static void i2c_flush_rxfifo(void)
+{
+ while (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE)
+ readl(&i2c_regs_p->ic_cmd_data);
+}
+
+/*
+ * i2c_wait_for_bb - Waits for bus busy
+ *
+ * Waits for bus busy
+ */
+static int i2c_wait_for_bb(void)
+{
+ unsigned long start_time_bb = get_timer(0);
+
+ while ((readl(&i2c_regs_p->ic_status) & IC_STATUS_MA) ||
+ !(readl(&i2c_regs_p->ic_status) & IC_STATUS_TFE)) {
+
+ /* Evaluate timeout */
+ if (get_timer(start_time_bb) > (unsigned long)(I2C_BYTE_TO_BB))
+ return 1;
+ }
+
+ return 0;
+}
+
+/* check parameters for i2c_read and i2c_write */
+static int check_params(uint addr, int alen, uchar *buffer, int len)
+{
+ if (buffer == NULL) {
+ printf("Buffer is invalid\n");
+ return 1;
+ }
+
+ if (alen > 1) {
+ printf("addr len %d not supported\n", alen);
+ return 1;
+ }
+
+ if (addr + len > 256) {
+ printf("address out of range\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+static int i2c_xfer_init(uchar chip, uint addr)
+{
+ if (i2c_wait_for_bb()) {
+ printf("Timed out waiting for bus\n");
+ return 1;
+ }
+
+ i2c_setaddress(chip);
+ writel(addr, &i2c_regs_p->ic_cmd_data);
+
+ return 0;
+}
+
+static int i2c_xfer_finish(void)
+{
+ ulong start_stop_det = get_timer(0);
+
+ while (1) {
+ if ((readl(&i2c_regs_p->ic_raw_intr_stat) & IC_STOP_DET)) {
+ readl(&i2c_regs_p->ic_clr_stop_det);
+ break;
+ } else if (get_timer(start_stop_det) > I2C_STOPDET_TO) {
+ break;
+ }
+ }
+
+ if (i2c_wait_for_bb()) {
+ printf("Timed out waiting for bus\n");
+ return 1;
+ }
+
+ i2c_flush_rxfifo();
+
+ /* Wait for read/write operation to complete on actual memory */
+ udelay(10000);
+
+ return 0;
+}
+
+/*
+ * i2c_read - Read from i2c memory
+ * @chip: target i2c address
+ * @addr: address to read from
+ * @alen:
+ * @buffer: buffer for read data
+ * @len: no of bytes to be read
+ *
+ * Read from i2c memory.
+ */
+int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+ unsigned long start_time_rx;
+
+ if (check_params(addr, alen, buffer, len)) {
+ return 1;
+ }
+
+ if (i2c_xfer_init(chip, addr)) {
+ return 1;
+ }
+
+ start_time_rx = get_timer(0);
+ while (len) {
+ writel(IC_CMD, &i2c_regs_p->ic_cmd_data);
+
+ if (readl(&i2c_regs_p->ic_status) & IC_STATUS_RFNE) {
+ *buffer++ = (uchar)readl(&i2c_regs_p->ic_cmd_data);
+ len--;
+ start_time_rx = get_timer(0);
+
+ } else if (get_timer(start_time_rx) > I2C_BYTE_TO) {
+ printf("Timed out. i2c read Failed\n");
+ return 1;
+ }
+ }
+
+ return i2c_xfer_finish();
+}
+
+/*
+ * i2c_write - Write to i2c memory
+ * @chip: target i2c address
+ * @addr: address to read from
+ * @alen:
+ * @buffer: buffer for read data
+ * @len: no of bytes to be read
+ *
+ * Write to i2c memory.
+ */
+int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
+{
+ int nb = len;
+ unsigned long start_time_tx;
+
+ if (check_params(addr, alen, buffer, len)) {
+ return 1;
+ }
+
+ if (i2c_xfer_init(chip, addr)) {
+ return 1;
+ }
+
+ start_time_tx = get_timer(0);
+ while (len) {
+ if (readl(&i2c_regs_p->ic_status) & IC_STATUS_TFNF) {
+ writel(*buffer, &i2c_regs_p->ic_cmd_data);
+ buffer++;
+ len--;
+ start_time_tx = get_timer(0);
+
+ } else if (get_timer(start_time_tx) > (nb * I2C_BYTE_TO)) {
+ printf("Timed out. i2c write Failed\n");
+ return 1;
+ }
+ }
+
+ return i2c_xfer_finish();
+}
+
+/*
+ * i2c_probe - Probe the i2c chip
+ */
+int i2c_probe(uchar chip)
+{
+ u32 tmp;
+
+ /*
+ * Try to read the first location of the chip.
+ */
+ return i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
+}
diff --git a/include/asm-arm/arch-spear/spr_i2c.h b/include/asm-arm/arch-spear/spr_i2c.h
new file mode 100755
index 0000000..7521ebc
--- /dev/null
+++ b/include/asm-arm/arch-spear/spr_i2c.h
@@ -0,0 +1,146 @@
+/*
+ * (C) Copyright 2009
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar at st.com.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef __SPR_I2C_H_
+#define __SPR_I2C_H_
+
+struct i2c_regs {
+ u32 ic_con;
+ u32 ic_tar;
+ u32 ic_sar;
+ u32 ic_hs_maddr;
+ u32 ic_cmd_data;
+ u32 ic_ss_scl_hcnt;
+ u32 ic_ss_scl_lcnt;
+ u32 ic_fs_scl_hcnt;
+ u32 ic_fs_scl_lcnt;
+ u32 ic_hs_scl_hcnt;
+ u32 ic_hs_scl_lcnt;
+ u32 ic_intr_stat;
+ u32 ic_intr_mask;
+ u32 ic_raw_intr_stat;
+ u32 ic_rx_tl;
+ u32 ic_tx_tl;
+ u32 ic_clr_intr;
+ u32 ic_clr_rx_under;
+ u32 ic_clr_rx_over;
+ u32 ic_clr_tx_over;
+ u32 ic_clr_rd_req;
+ u32 ic_clr_tx_abrt;
+ u32 ic_clr_rx_done;
+ u32 ic_clr_activity;
+ u32 ic_clr_stop_det;
+ u32 ic_clr_start_det;
+ u32 ic_clr_gen_call;
+ u32 ic_enable;
+ u32 ic_status;
+ u32 ic_txflr;
+ u32 ix_rxflr;
+ u32 reserved_1;
+ u32 ic_tx_abrt_source;
+};
+
+#define IC_CLK 166
+#define NANO_TO_MICRO 1000
+
+/* High and low times in different speed modes (in ns) */
+#define MIN_SS_SCL_HIGHTIME 4000
+#define MIN_SS_SCL_LOWTIME 5000
+#define MIN_FS_SCL_HIGHTIME 800
+#define MIN_FS_SCL_LOWTIME 1700
+#define MIN_HS_SCL_HIGHTIME 60
+#define MIN_HS_SCL_LOWTIME 160
+
+/* Worst case timeout for 1 byte is kept as 2ms */
+#define I2C_BYTE_TO (CONFIG_SYS_HZ/500)
+#define I2C_STOPDET_TO (CONFIG_SYS_HZ/500)
+#define I2C_BYTE_TO_BB (I2C_BYTE_TO * 16)
+
+/* i2c control register definitions */
+#define IC_CON_SD 0x0040
+#define IC_CON_RE 0x0020
+#define IC_CON_10BITADDRMASTER 0x0010
+#define IC_CON_10BITADDR_SLAVE 0x0008
+#define IC_CON_SPD_MSK 0x0006
+#define IC_CON_SPD_SS 0x0002
+#define IC_CON_SPD_FS 0x0004
+#define IC_CON_SPD_HS 0x0006
+#define IC_CON_MM 0x0001
+
+/* i2c target address register definitions */
+#define TAR_ADDR 0x0050
+
+/* i2c slave address register definitions */
+#define IC_SLAVE_ADDR 0x0002
+
+/* i2c data buffer and command register definitions */
+#define IC_CMD 0x0100
+
+/* i2c interrupt status register definitions */
+#define IC_GEN_CALL 0x0800
+#define IC_START_DET 0x0400
+#define IC_STOP_DET 0x0200
+#define IC_ACTIVITY 0x0100
+#define IC_RX_DONE 0x0080
+#define IC_TX_ABRT 0x0040
+#define IC_RD_REQ 0x0020
+#define IC_TX_EMPTY 0x0010
+#define IC_TX_OVER 0x0008
+#define IC_RX_FULL 0x0004
+#define IC_RX_OVER 0x0002
+#define IC_RX_UNDER 0x0001
+
+/* fifo threshold register definitions */
+#define IC_TL0 0x00
+#define IC_TL1 0x01
+#define IC_TL2 0x02
+#define IC_TL3 0x03
+#define IC_TL4 0x04
+#define IC_TL5 0x05
+#define IC_TL6 0x06
+#define IC_TL7 0x07
+#define IC_RX_TL IC_TL0
+#define IC_TX_TL IC_TL0
+
+/* i2c enable register definitions */
+#define IC_ENABLE_0B 0x0001
+
+/* i2c status register definitions */
+#define IC_STATUS_SA 0x0040
+#define IC_STATUS_MA 0x0020
+#define IC_STATUS_RFF 0x0010
+#define IC_STATUS_RFNE 0x0008
+#define IC_STATUS_TFE 0x0004
+#define IC_STATUS_TFNF 0x0002
+#define IC_STATUS_ACT 0x0001
+
+/* Speed Selection */
+#define IC_SPEED_MODE_STANDARD 1
+#define IC_SPEED_MODE_FAST 2
+#define IC_SPEED_MODE_MAX 3
+
+#define I2C_MAX_SPEED 3400000
+#define I2C_FAST_SPEED 400000
+#define I2C_STANDARD_SPEED 100000
+
+#endif /* __SPR_I2C_H_ */
diff --git a/include/configs/spear.h b/include/configs/spear.h
index 58065f6..c07d5d4 100755
--- a/include/configs/spear.h
+++ b/include/configs/spear.h
@@ -61,7 +61,7 @@
* I2C driver configuration
*/
#define CONFIG_HARD_I2C
-#define CONFIG_SPEARI2C
+#define CONFIG_SPEAR_I2C
#define CONFIG_SYS_I2C_SPEED 400000
#define CONFIG_SYS_I2C_SLAVE 0x02

--
1.6.0.2