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path: root/drivers/i2c/sh_sh7734_i2c.c
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Diffstat (limited to 'drivers/i2c/sh_sh7734_i2c.c')
-rw-r--r--drivers/i2c/sh_sh7734_i2c.c387
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/i2c/sh_sh7734_i2c.c b/drivers/i2c/sh_sh7734_i2c.c
new file mode 100644
index 0000000000..9da173d31e
--- /dev/null
+++ b/drivers/i2c/sh_sh7734_i2c.c
@@ -0,0 +1,387 @@
+/*
+ * Copyright (C) 2012 Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ *
+ * 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 <i2c.h>
+#include <asm/io.h>
+
+struct sh_i2c {
+ u8 iccr1;
+ u8 iccr2;
+ u8 icmr;
+ u8 icier;
+ u8 icsr;
+ u8 sar;
+ u8 icdrt;
+ u8 icdrr;
+ u8 nf2cyc;
+ u8 __pad0;
+ u8 __pad1;
+};
+
+static struct sh_i2c *base;
+static u8 iccr1_cks, nf2cyc;
+
+/* ICCR1 */
+#define SH_I2C_ICCR1_ICE (1 << 7)
+#define SH_I2C_ICCR1_RCVD (1 << 6)
+#define SH_I2C_ICCR1_MST (1 << 5)
+#define SH_I2C_ICCR1_TRS (1 << 4)
+#define SH_I2C_ICCR1_MTRS \
+ (SH_I2C_ICCR1_MST | SH_I2C_ICCR1_TRS)
+
+/* ICCR1 */
+#define SH_I2C_ICCR2_BBSY (1 << 7)
+#define SH_I2C_ICCR2_SCP (1 << 6)
+#define SH_I2C_ICCR2_SDAO (1 << 5)
+#define SH_I2C_ICCR2_SDAOP (1 << 4)
+#define SH_I2C_ICCR2_SCLO (1 << 3)
+#define SH_I2C_ICCR2_IICRST (1 << 1)
+
+#define SH_I2C_ICIER_TIE (1 << 7)
+#define SH_I2C_ICIER_TEIE (1 << 6)
+#define SH_I2C_ICIER_RIE (1 << 5)
+#define SH_I2C_ICIER_NAKIE (1 << 4)
+#define SH_I2C_ICIER_STIE (1 << 3)
+#define SH_I2C_ICIER_ACKE (1 << 2)
+#define SH_I2C_ICIER_ACKBR (1 << 1)
+#define SH_I2C_ICIER_ACKBT (1 << 0)
+
+#define SH_I2C_ICSR_TDRE (1 << 7)
+#define SH_I2C_ICSR_TEND (1 << 6)
+#define SH_I2C_ICSR_RDRF (1 << 5)
+#define SH_I2C_ICSR_NACKF (1 << 4)
+#define SH_I2C_ICSR_STOP (1 << 3)
+#define SH_I2C_ICSR_ALOVE (1 << 2)
+#define SH_I2C_ICSR_AAS (1 << 1)
+#define SH_I2C_ICSR_ADZ (1 << 0)
+
+#define IRQ_WAIT 1000
+
+static void sh_i2c_send_stop(struct sh_i2c *base)
+{
+ clrbits_8(&base->iccr2, SH_I2C_ICCR2_BBSY | SH_I2C_ICCR2_SCP);
+}
+
+static int check_icsr_bits(struct sh_i2c *base, u8 bits)
+{
+ int i;
+
+ for (i = 0; i < IRQ_WAIT; i++) {
+ if (bits & readb(&base->icsr))
+ return 0;
+ udelay(10);
+ }
+
+ return 1;
+}
+
+static int check_stop(struct sh_i2c *base)
+{
+ int ret = check_icsr_bits(base, SH_I2C_ICSR_STOP);
+ clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
+
+ return ret;
+}
+
+static int check_tend(struct sh_i2c *base, int stop)
+{
+ int ret = check_icsr_bits(base, SH_I2C_ICSR_TEND);
+
+ if (stop) {
+ clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
+ sh_i2c_send_stop(base);
+ }
+
+ clrbits_8(&base->icsr, SH_I2C_ICSR_TEND);
+ return ret;
+}
+
+static int check_tdre(struct sh_i2c *base)
+{
+ return check_icsr_bits(base, SH_I2C_ICSR_TDRE);
+}
+
+static int check_rdrf(struct sh_i2c *base)
+{
+ return check_icsr_bits(base, SH_I2C_ICSR_RDRF);
+}
+
+static int check_bbsy(struct sh_i2c *base)
+{
+ int i;
+
+ for (i = 0 ; i < IRQ_WAIT ; i++) {
+ if (!(SH_I2C_ICCR2_BBSY & readb(&base->iccr2)))
+ return 0;
+ udelay(10);
+ }
+ return 1;
+}
+
+static int check_ackbr(struct sh_i2c *base)
+{
+ int i;
+
+ for (i = 0 ; i < IRQ_WAIT ; i++) {
+ if (!(SH_I2C_ICIER_ACKBR & readb(&base->icier)))
+ return 0;
+ udelay(10);
+ }
+
+ return 1;
+}
+
+static void sh_i2c_reset(struct sh_i2c *base)
+{
+ setbits_8(&base->iccr2, SH_I2C_ICCR2_IICRST);
+
+ udelay(100);
+
+ clrbits_8(&base->iccr2, SH_I2C_ICCR2_IICRST);
+}
+
+static int i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg)
+{
+ if (check_bbsy(base)) {
+ puts("i2c bus busy\n");
+ goto fail;
+ }
+
+ setbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
+ clrsetbits_8(&base->iccr2, SH_I2C_ICCR2_SCP, SH_I2C_ICCR2_BBSY);
+
+ writeb((id << 1), &base->icdrt);
+
+ if (check_tend(base, 0)) {
+ puts("TEND check fail...\n");
+ goto fail;
+ }
+
+ if (check_ackbr(base)) {
+ check_tend(base, 0);
+ sh_i2c_send_stop(base);
+ goto fail;
+ }
+
+ writeb(reg, &base->icdrt);
+
+ if (check_tdre(base)) {
+ puts("TDRE check fail...\n");
+ goto fail;
+ }
+
+ if (check_tend(base, 0)) {
+ puts("TEND check fail...\n");
+ goto fail;
+ }
+
+ return 0;
+fail:
+
+ return 1;
+}
+
+static int
+i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 *val, int size)
+{
+ int i;
+
+ if (i2c_set_addr(base, id, reg)) {
+ puts("Fail set slave address\n");
+ return 1;
+ }
+
+ for (i = 0; i < size; i++) {
+ writeb(val[i], &base->icdrt);
+ check_tdre(base);
+ }
+
+ check_tend(base, 1);
+ check_stop(base);
+
+ udelay(100);
+
+ clrbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
+ clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
+ sh_i2c_reset(base);
+
+ return 0;
+}
+
+static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
+{
+ u8 ret = 0;
+
+ if (i2c_set_addr(base, id, reg)) {
+ puts("Fail set slave address\n");
+ goto fail;
+ }
+
+ clrsetbits_8(&base->iccr2, SH_I2C_ICCR2_SCP, SH_I2C_ICCR2_BBSY);
+ writeb((id << 1) | 1, &base->icdrt);
+
+ if (check_tend(base, 0))
+ puts("TDRE check fail...\n");
+
+ clrsetbits_8(&base->iccr1, SH_I2C_ICCR1_TRS, SH_I2C_ICCR1_MST);
+ clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
+ setbits_8(&base->icier, SH_I2C_ICIER_ACKBT);
+ setbits_8(&base->iccr1, SH_I2C_ICCR1_RCVD);
+
+ /* read data (dummy) */
+ ret = readb(&base->icdrr);
+
+ if (check_rdrf(base)) {
+ puts("check RDRF error\n");
+ goto fail;
+ }
+
+ clrbits_8(&base->icsr, SH_I2C_ICSR_STOP);
+ udelay(1000);
+
+ sh_i2c_send_stop(base);
+
+ if (check_stop(base)) {
+ puts("check STOP error\n");
+ goto fail;
+ }
+
+ clrbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS);
+ clrbits_8(&base->icsr, SH_I2C_ICSR_TDRE);
+
+ /* data read */
+ ret = readb(&base->icdrr);
+
+fail:
+ clrbits_8(&base->iccr1, SH_I2C_ICCR1_RCVD);
+
+ return ret;
+}
+
+#ifdef CONFIG_I2C_MULTI_BUS
+static unsigned int current_bus;
+
+/**
+ * i2c_set_bus_num - change active I2C bus
+ * @bus: bus index, zero based
+ * @returns: 0 on success, non-0 on failure
+ */
+int i2c_set_bus_num(unsigned int bus)
+{
+ switch (bus) {
+ case 0:
+ base = (void *)CONFIG_SH_I2C_BASE0;
+ break;
+ case 1:
+ base = (void *)CONFIG_SH_I2C_BASE1;
+ break;
+ default:
+ printf("Bad bus: %d\n", bus);
+ return -1;
+ }
+
+ current_bus = bus;
+
+ return 0;
+}
+
+/**
+ * i2c_get_bus_num - returns index of active I2C bus
+ */
+unsigned int i2c_get_bus_num(void)
+{
+ return current_bus;
+}
+#endif
+
+void i2c_init(int speed, int slaveaddr)
+{
+#ifdef CONFIG_I2C_MULTI_BUS
+ current_bus = 0;
+#endif
+ base = (struct sh_i2c *)CONFIG_SH_I2C_BASE0;
+
+ if (speed == 400000)
+ iccr1_cks = 0x07;
+ else
+ iccr1_cks = 0x0F;
+
+ nf2cyc = 1;
+
+ /* Reset */
+ sh_i2c_reset(base);
+
+ /* ICE enable and set clock */
+ writeb(SH_I2C_ICCR1_ICE | iccr1_cks, &base->iccr1);
+ writeb(nf2cyc, &base->nf2cyc);
+}
+
+/*
+ * i2c_read: - Read multiple bytes from an i2c device
+ *
+ * The higher level routines take into account that this function is only
+ * called with len < page length of the device (see configuration file)
+ *
+ * @chip: address of the chip which is to be read
+ * @addr: i2c data address within the chip
+ * @alen: length of the i2c data address (1..2 bytes)
+ * @buffer: where to write the data
+ * @len: how much byte do we want to read
+ * @return: 0 in case of success
+ */
+int i2c_read(u8 chip, u32 addr, int alen, u8 *buffer, int len)
+{
+ int i = 0;
+ for (i = 0; i < len; i++)
+ buffer[i] = i2c_raw_read(base, chip, addr + i);
+
+ return 0;
+}
+
+/*
+ * i2c_write: - Write multiple bytes to an i2c device
+ *
+ * The higher level routines take into account that this function is only
+ * called with len < page length of the device (see configuration file)
+ *
+ * @chip: address of the chip which is to be written
+ * @addr: i2c data address within the chip
+ * @alen: length of the i2c data address (1..2 bytes)
+ * @buffer: where to find the data to be written
+ * @len: how much byte do we want to read
+ * @return: 0 in case of success
+ */
+int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len)
+{
+ return i2c_raw_write(base, chip, addr, buffer, len);
+}
+
+/*
+ * i2c_probe: - Test if a chip answers for a given i2c address
+ *
+ * @chip: address of the chip which is searched for
+ * @return: 0 if a chip was found, -1 otherwhise
+ */
+int i2c_probe(u8 chip)
+{
+ u8 byte;
+ return i2c_read(chip, 0, 0, &byte, 1);
+}