From 2d344a2ab27d8704efd09088ee00be194b3556eb Mon Sep 17 00:00:00 2001 From: Nobuhiro Iwamatsu Date: Thu, 1 Mar 2012 17:56:35 +0000 Subject: [PATCH] sh: i2c: Add support I2C controller of SH7734 Renesas SH7734 has two I2C interfaceis. This supports these I2C. V5: - include i2c.h. - Add check of icsr bit polling logic. - Implement i2c_probe. 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 Acked-by: Heiko Schocher Signed-off-by: Nobuhiro Iwamatsu Acked-by: Mike Frysinger --- drivers/i2c/Makefile | 1 + drivers/i2c/sh_sh7734_i2c.c | 387 ++++++++++++++++++++++++++++++++++++ 2 files changed, 388 insertions(+) create mode 100644 drivers/i2c/sh_sh7734_i2c.c diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile index f86e46c111..42913f7cbb 100644 --- a/drivers/i2c/Makefile +++ b/drivers/i2c/Makefile @@ -45,6 +45,7 @@ COBJS-$(CONFIG_TEGRA_I2C) += tegra_i2c.o COBJS-$(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 0000000000..9da173d31e --- /dev/null +++ b/drivers/i2c/sh_sh7734_i2c.c @@ -0,0 +1,387 @@ +/* + * Copyright (C) 2012 Nobuhiro Iwamatsu + * 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 +#include +#include + +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); +} -- 2.25.1