]> git.kernelconcepts.de Git - karo-tx-uboot.git/commitdiff
SPEAr : i2c driver support added for SPEAr SoCs
authorVipin KUMAR <vipin.kumar@st.com>
Fri, 15 Jan 2010 13:45:44 +0000 (19:15 +0530)
committerTom Rix <Tom.Rix@windriver.com>
Thu, 21 Jan 2010 19:35:16 +0000 (13:35 -0600)
SPEAr SoCs contain a synopsys i2c controller.
This patch adds the driver for this IP.

Signed-off-by: Vipin <vipin.kumar@st.com>
drivers/i2c/Makefile [changed mode: 0644->0755]
drivers/i2c/spr_i2c.c [new file with mode: 0755]
include/asm-arm/arch-spear/spr_i2c.h [new file with mode: 0755]

old mode 100644 (file)
new mode 100755 (executable)
index b860e89..29bda85
@@ -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 (executable)
index 0000000..eabfe84
--- /dev/null
@@ -0,0 +1,331 @@
+/*
+ * (C) Copyright 2009
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar@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/hardware.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 (executable)
index 0000000..7521ebc
--- /dev/null
@@ -0,0 +1,146 @@
+/*
+ * (C) Copyright 2009
+ * Vipin Kumar, ST Micoelectronics, vipin.kumar@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_ */