diff options
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/sh_i2c.c | 135 |
1 files changed, 102 insertions, 33 deletions
diff --git a/drivers/i2c/sh_i2c.c b/drivers/i2c/sh_i2c.c index 3147123bb..44ba90ef5 100644 --- a/drivers/i2c/sh_i2c.c +++ b/drivers/i2c/sh_i2c.c @@ -43,12 +43,18 @@ static struct sh_i2c *base; #define SH_I2C_ICCR_SCP (1 << 0) /* ICSR / ICIC */ -#define SH_IC_BUSY (1 << 3) +#define SH_IC_BUSY (1 << 4) #define SH_IC_TACK (1 << 2) #define SH_IC_WAIT (1 << 1) #define SH_IC_DTE (1 << 0) -static u8 iccl, icch; +#ifdef CONFIG_SH_I2C_8BIT +/* store 8th bit of iccl and icch in ICIC register */ +#define SH_I2C_ICIC_ICCLB8 (1 << 7) +#define SH_I2C_ICIC_ICCHB8 (1 << 6) +#endif + +static u16 iccl, icch; #define IRQ_WAIT 1000 @@ -63,6 +69,20 @@ static void irq_dte(struct sh_i2c *base) } } +static int irq_dte_with_tack(struct sh_i2c *base) +{ + int i; + + for (i = 0 ; i < IRQ_WAIT ; i++) { + if (SH_IC_DTE & readb(&base->icsr)) + break; + if (SH_IC_TACK & readb(&base->icsr)) + return -1; + udelay(10); + } + return 0; +} + static void irq_busy(struct sh_i2c *base) { int i; @@ -74,71 +94,97 @@ static void irq_busy(struct sh_i2c *base) } } -static void i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop) +static int i2c_set_addr(struct sh_i2c *base, u8 id, u8 reg, int stop) { - writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr); - writeb(readb(&base->iccr) | SH_I2C_ICCR_ICE, &base->iccr); + u8 icic = SH_IC_TACK; - writeb(iccl, &base->iccl); - writeb(icch, &base->icch); - writeb(0, &base->icic); + clrbits_8(&base->iccr, SH_I2C_ICCR_ICE); + setbits_8(&base->iccr, SH_I2C_ICCR_ICE); + + writeb(iccl & 0xff, &base->iccl); + writeb(icch & 0xff, &base->icch); +#ifdef CONFIG_SH_I2C_8BIT + if (iccl > 0xff) + icic |= SH_I2C_ICIC_ICCLB8; + if (icch > 0xff) + icic |= SH_I2C_ICIC_ICCHB8; +#endif + writeb(icic, &base->icic); writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS|SH_I2C_ICCR_BUSY), &base->iccr); irq_dte(base); + clrbits_8(&base->icsr, SH_IC_TACK); writeb(id << 1, &base->icdr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + return -1; writeb(reg, &base->icdr); if (stop) writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS), &base->iccr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + return -1; + return 0; } static void i2c_finish(struct sh_i2c *base) { writeb(0, &base->icsr); - writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr); + clrbits_8(&base->iccr, SH_I2C_ICCR_ICE); } -static void i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 val) +static int i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 val) { - i2c_set_addr(base, id, reg, 0); + int ret = -1; + if (i2c_set_addr(base, id, reg, 0) != 0) + goto exit0; udelay(10); writeb(val, &base->icdr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + goto exit0; writeb((SH_I2C_ICCR_ICE | SH_I2C_ICCR_RTS), &base->iccr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + goto exit0; irq_busy(base); - + ret = 0; +exit0: i2c_finish(base); + return ret; } -static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg) +static int i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg) { - u8 ret; + int ret = -1; - i2c_set_addr(base, id, reg, 1); +#if defined(CONFIG_SH73A0) + if (i2c_set_addr(base, id, reg, 0) != 0) + goto exit0; +#else + if (i2c_set_addr(base, id, reg, 1) != 0) + goto exit0; udelay(100); +#endif writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RTS|SH_I2C_ICCR_BUSY), &base->iccr); irq_dte(base); writeb(id << 1 | 0x01, &base->icdr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + goto exit0; writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_SCP), &base->iccr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + goto exit0; - ret = readb(&base->icdr); + ret = readb(&base->icdr) & 0xff; writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RACK), &base->iccr); readb(&base->icdr); /* Dummy read */ irq_busy(base); - +exit0: i2c_finish(base); return ret; @@ -166,6 +212,21 @@ int i2c_set_bus_num(unsigned int bus) case 1: base = (void *)CONFIG_SH_I2C_BASE1; break; +#ifdef CONFIG_SH_I2C_BASE2 + case 2: + base = (void *)CONFIG_SH_I2C_BASE2; + break; +#endif +#ifdef CONFIG_SH_I2C_BASE3 + case 3: + base = (void *)CONFIG_SH_I2C_BASE3; + break; +#endif +#ifdef CONFIG_SH_I2C_BASE4 + case 4: + base = (void *)CONFIG_SH_I2C_BASE4; + break; +#endif default: return -1; } @@ -206,18 +267,18 @@ void i2c_init(int speed, int slaveaddr) denom = speed * (CONFIG_SH_I2C_DATA_HIGH + CONFIG_SH_I2C_DATA_LOW); tmp = num * 10 / denom; if (tmp % 10 >= 5) - iccl = (u8)((num/denom) + 1); + iccl = (u16)((num/denom) + 1); else - iccl = (u8)(num/denom); + iccl = (u16)(num/denom); /* Calculate the value for icch. From the data sheet: icch = (p clock / transfer rate) * (H / (L + H)) */ num = CONFIG_SH_I2C_CLOCK * CONFIG_SH_I2C_DATA_HIGH; tmp = num * 10 / denom; if (tmp % 10 >= 5) - icch = (u8)((num/denom) + 1); + icch = (u16)((num/denom) + 1); else - icch = (u8)(num/denom); + icch = (u16)(num/denom); } /* @@ -235,10 +296,14 @@ void i2c_init(int speed, int slaveaddr) */ int i2c_read(u8 chip, u32 addr, int alen, u8 *buffer, int len) { + int ret; int i = 0; - for (i = 0 ; i < len ; i++) - buffer[i] = i2c_raw_read(base, chip, addr + i); - + for (i = 0 ; i < len ; i++) { + ret = i2c_raw_read(base, chip, addr + i); + if (ret < 0) + return -1; + buffer[i] = ret & 0xff; + } return 0; } @@ -259,8 +324,8 @@ int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len) { int i = 0; for (i = 0; i < len ; i++) - i2c_raw_write(base, chip, addr + i, buffer[i]); - + if (i2c_raw_write(base, chip, addr + i, buffer[i]) != 0) + return -1; return 0; } @@ -272,5 +337,9 @@ int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len) */ int i2c_probe(u8 chip) { - return 0; + int ret; + + ret = i2c_set_addr(base, chip, 0, 1); + i2c_finish(base); + return ret; } |