Patchwork [U-Boot,v4] sh: i2c: Add support I2C controller of SH7734

login
register
mail settings
Submitter Nobuhiro Iwamatsu
Date March 1, 2012, 2:58 a.m.
Message ID <1330570723-10002-1-git-send-email-nobuhiro.iwamatsu.yj@renesas.com>
Download mbox | patch
Permalink /patch/143891/
State Changes Requested
Delegated to: Heiko Schocher
Headers show

Comments

Nobuhiro Iwamatsu - March 1, 2012, 2:58 a.m.
Renesas SH7734 has two I2C interfaceis.
This supports these I2C.

V4: - Remove sh_i2c_dump_reg function.
    - Use puts() when there's no format.
    - Chnage check for I2C bus number.
    - Remove space before the semi-colon.
V3: - Fix error for whitespace.
V2: - Changed bit control to use the clr|set|clrsetbits_* functions.
    - Fix wrong comment style.
    - Add new line before for loop in i2c_read.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Acked-by: Heiko Schocher <hs@denx.de>
---
 drivers/i2c/Makefile        |    1 +
 drivers/i2c/sh_sh7734_i2c.c |  426 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 427 insertions(+), 0 deletions(-)
 create mode 100644 drivers/i2c/sh_sh7734_i2c.c
Mike Frysinger - March 1, 2012, 3:24 a.m.
On Wednesday 29 February 2012 21:58:42 Nobuhiro Iwamatsu wrote:
> --- /dev/null
> +++ b/drivers/i2c/sh_sh7734_i2c.c
>
> +#include <common.h>
> +#include <asm/io.h>

should include i2c.h too so you know your funcs match the prototypes everyone 
else uses

> +static int check_stop(struct sh_i2c *base)
> +{
> +	int i, ret = 1;
> +
> +	for (i = 0; i < IRQ_WAIT; i++) {
> +		if (SH_I2C_ICSR_STOP & readb(&base->icsr)) {
> +			ret = 0;
> +			break;
> +		}
> +		udelay(10);
> +	}
> +
> +	clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
> +
> +	return ret;
> +}
> +
> +static int check_tend(struct sh_i2c *base, int stop)
> +{
> +	int i, ret = 1;
> +
> +	for (i = 0; i < IRQ_WAIT; i++) {
> +		if (SH_I2C_ICSR_TEND & readb(&base->icsr)) {
> +			ret = 0;
> +			break;
> +		}
> +		udelay(10);
> +	}
> +
> +	if (stop) {
> +		u8 data;
> +
> +		clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
> +
> +		sh_i2c_send_stop(base);
> +	}
> +
> +	clrbits_le8(&base->icsr, SH_I2C_ICSR_TEND);
> +
> +	return ret;
> +}
> +
> +static int check_tdre(struct sh_i2c *base)
> +{
> +	int i;
> +
> +	for (i = 0; i < IRQ_WAIT; i++) {
> +		if (SH_I2C_ICSR_TDRE & readb(&base->icsr))
> +			return 0;
> +		udelay(10);
> +	}
> +
> +	return 1;
> +}
> +
> +static int check_rdrf(struct sh_i2c *base)
> +{
> +	int i;
> +
> +	for (i = 0; i < IRQ_WAIT; i++) {
> +		if (SH_I2C_ICSR_RDRF & readb(&base->icsr))
> +			return 0;
> +		udelay(10);
> +	}
> +
> +	return 1;
> +}

you've got the same icsr bit polling logic here.  probably better to put it 
into a dedicated func which takes the bit flag to check and the rest will call 
that.
	static int check_icsr_bit(struct sh_i2c *base, uint bit)
	{
		int i;

		for (i = 0; i < IRQ_WAIT; i++) {
			if (bit & readb(&base->icsr))
				return 0;
			udelay(10);
		}

		return 1;
	}

	static int check_tdre(struct sh_i2c *base)
	{
		return check_icsr_bit(base, SH_I2C_ICSR_TDRE);
	}

> +static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
> +{
> ...
> +	writeb(id << 1 | 1, &base->icdrt);

shifting and bit ops can lead to unexpected behavior ... might be better:
	writeb((id << 1) | 1, &base->icdrt);

> +/*
> + * 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)
> +{
> +	return 0;
> +}

should implement this.  look at the Blackfin twi driver for an easy one.
-mike
Nobuhiro Iwamatsu - March 2, 2012, 3:40 a.m.
Hi, Mike.

2012/3/1 Mike Frysinger <vapier@gentoo.org>:
> On Wednesday 29 February 2012 21:58:42 Nobuhiro Iwamatsu wrote:
>> --- /dev/null
>> +++ b/drivers/i2c/sh_sh7734_i2c.c
>>
>> +#include <common.h>
>> +#include <asm/io.h>
>
> should include i2c.h too so you know your funcs match the prototypes everyone
> else uses

OK.

>
>> +static int check_stop(struct sh_i2c *base)
>> +{
>> +     int i, ret = 1;
>> +
>> +     for (i = 0; i < IRQ_WAIT; i++) {
>> +             if (SH_I2C_ICSR_STOP & readb(&base->icsr)) {
>> +                     ret = 0;
>> +                     break;
>> +             }
>> +             udelay(10);
>> +     }
>> +
>> +     clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
>> +
>> +     return ret;
>> +}
>> +
>> +static int check_tend(struct sh_i2c *base, int stop)
>> +{
>> +     int i, ret = 1;
>> +
>> +     for (i = 0; i < IRQ_WAIT; i++) {
>> +             if (SH_I2C_ICSR_TEND & readb(&base->icsr)) {
>> +                     ret = 0;
>> +                     break;
>> +             }
>> +             udelay(10);
>> +     }
>> +
>> +     if (stop) {
>> +             u8 data;
>> +
>> +             clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
>> +
>> +             sh_i2c_send_stop(base);
>> +     }
>> +
>> +     clrbits_le8(&base->icsr, SH_I2C_ICSR_TEND);
>> +
>> +     return ret;
>> +}
>> +
>> +static int check_tdre(struct sh_i2c *base)
>> +{
>> +     int i;
>> +
>> +     for (i = 0; i < IRQ_WAIT; i++) {
>> +             if (SH_I2C_ICSR_TDRE & readb(&base->icsr))
>> +                     return 0;
>> +             udelay(10);
>> +     }
>> +
>> +     return 1;
>> +}
>> +
>> +static int check_rdrf(struct sh_i2c *base)
>> +{
>> +     int i;
>> +
>> +     for (i = 0; i < IRQ_WAIT; i++) {
>> +             if (SH_I2C_ICSR_RDRF & readb(&base->icsr))
>> +                     return 0;
>> +             udelay(10);
>> +     }
>> +
>> +     return 1;
>> +}
>
> you've got the same icsr bit polling logic here.  probably better to put it
> into a dedicated func which takes the bit flag to check and the rest will call
> that.
>        static int check_icsr_bit(struct sh_i2c *base, uint bit)
>        {
>                int i;
>
>                for (i = 0; i < IRQ_WAIT; i++) {
>                        if (bit & readb(&base->icsr))
>                                return 0;
>                        udelay(10);
>                }
>
>                return 1;
>        }
>
>        static int check_tdre(struct sh_i2c *base)
>        {
>                return check_icsr_bit(base, SH_I2C_ICSR_TDRE);
>        }

OK, I fixed.
>
>> +static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
>> +{
>> ...
>> +     writeb(id << 1 | 1, &base->icdrt);
>
> shifting and bit ops can lead to unexpected behavior ... might be better:
>        writeb((id << 1) | 1, &base->icdrt);
>

OK, I fixed.

>> +/*
>> + * 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)
>> +{
>> +     return 0;
>> +}
>
> should implement this.  look at the Blackfin twi driver for an easy one.

Thanks for your infomation.
I implemented this.

Thanks,
  Nobuhiro

Patch

diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 504db03..506269d 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -44,6 +44,7 @@  COBJS-$(CONFIG_SPEAR_I2C) += spr_i2c.o
 COBJS-$(CONFIG_TSI108_I2C) += tsi108_i2c.o
 COBJS-$(CONFIG_U8500_I2C) += u8500_i2c.o
 COBJS-$(CONFIG_SH_I2C) += sh_i2c.o
+COBJS-$(CONFIG_SH_SH7734_I2C) += sh_sh7734_i2c.o
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)
diff --git a/drivers/i2c/sh_sh7734_i2c.c b/drivers/i2c/sh_sh7734_i2c.c
new file mode 100644
index 0000000..5cabaca
--- /dev/null
+++ b/drivers/i2c/sh_sh7734_i2c.c
@@ -0,0 +1,426 @@ 
+/*
+ * 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 <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_le8(&base->iccr2, (SH_I2C_ICCR2_BBSY | SH_I2C_ICCR2_SCP));
+}
+
+static int check_stop(struct sh_i2c *base)
+{
+	int i, ret = 1;
+
+	for (i = 0; i < IRQ_WAIT; i++) {
+		if (SH_I2C_ICSR_STOP & readb(&base->icsr)) {
+			ret = 0;
+			break;
+		}
+		udelay(10);
+	}
+
+	clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
+
+	return ret;
+}
+
+static int check_tend(struct sh_i2c *base, int stop)
+{
+	int i, ret = 1;
+
+	for (i = 0; i < IRQ_WAIT; i++) {
+		if (SH_I2C_ICSR_TEND & readb(&base->icsr)) {
+			ret = 0;
+			break;
+		}
+		udelay(10);
+	}
+
+	if (stop) {
+		u8 data;
+
+		clrbits_le8(&base->icsr, SH_I2C_ICSR_STOP);
+
+		sh_i2c_send_stop(base);
+	}
+
+	clrbits_le8(&base->icsr, SH_I2C_ICSR_TEND);
+
+	return ret;
+}
+
+static int check_tdre(struct sh_i2c *base)
+{
+	int i;
+
+	for (i = 0; i < IRQ_WAIT; i++) {
+		if (SH_I2C_ICSR_TDRE & readb(&base->icsr))
+			return 0;
+		udelay(10);
+	}
+
+	return 1;
+}
+
+static int check_rdrf(struct sh_i2c *base)
+{
+	int i;
+
+	for (i = 0; i < IRQ_WAIT; i++) {
+		if (SH_I2C_ICSR_RDRF & readb(&base->icsr))
+			return 0;
+		udelay(10);
+	}
+
+	return 1;
+}
+
+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)
+{
+	u8 data;
+
+	if (check_bbsy(base)) {
+		outs("i2c bus busy\n");
+		goto fail;
+	}
+
+	setbits_8(&base->iccr1, SH_I2C_ICCR1_MTRS)
+
+	clrsetbits_8(&base->iccr1, 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;
+	u8 data;
+
+	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->iccr2, 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)
+{
+	int num, denom, tmp;
+
+#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)
+{
+	int ret;
+
+	ret = i2c_raw_write(base, chip, addr, buffer, len);
+
+	return 0;
+}
+
+/*
+ * 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)
+{
+	return 0;
+}