diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-pxa.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-pxa.c | 94 |
1 files changed, 77 insertions, 17 deletions
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index 44d838410f1..906f9b9d715 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -38,7 +38,44 @@ #include <asm/irq.h> #include <asm/io.h> #include <mach/i2c.h> -#include <mach/pxa-regs.h> + +/* + * I2C registers and bit definitions + */ +#define IBMR (0x00) +#define IDBR (0x08) +#define ICR (0x10) +#define ISR (0x18) +#define ISAR (0x20) + +#define ICR_START (1 << 0) /* start bit */ +#define ICR_STOP (1 << 1) /* stop bit */ +#define ICR_ACKNAK (1 << 2) /* send ACK(0) or NAK(1) */ +#define ICR_TB (1 << 3) /* transfer byte bit */ +#define ICR_MA (1 << 4) /* master abort */ +#define ICR_SCLE (1 << 5) /* master clock enable */ +#define ICR_IUE (1 << 6) /* unit enable */ +#define ICR_GCD (1 << 7) /* general call disable */ +#define ICR_ITEIE (1 << 8) /* enable tx interrupts */ +#define ICR_IRFIE (1 << 9) /* enable rx interrupts */ +#define ICR_BEIE (1 << 10) /* enable bus error ints */ +#define ICR_SSDIE (1 << 11) /* slave STOP detected int enable */ +#define ICR_ALDIE (1 << 12) /* enable arbitration interrupt */ +#define ICR_SADIE (1 << 13) /* slave address detected int enable */ +#define ICR_UR (1 << 14) /* unit reset */ +#define ICR_FM (1 << 15) /* fast mode */ + +#define ISR_RWM (1 << 0) /* read/write mode */ +#define ISR_ACKNAK (1 << 1) /* ack/nak status */ +#define ISR_UB (1 << 2) /* unit busy */ +#define ISR_IBB (1 << 3) /* bus busy */ +#define ISR_SSD (1 << 4) /* slave stop detected */ +#define ISR_ALD (1 << 5) /* arbitration loss detected */ +#define ISR_ITE (1 << 6) /* tx buffer empty */ +#define ISR_IRF (1 << 7) /* rx buffer full */ +#define ISR_GCAD (1 << 8) /* general call address detected */ +#define ISR_SAD (1 << 9) /* slave address detected */ +#define ISR_BED (1 << 10) /* bus error no ACK/NAK */ struct pxa_i2c { spinlock_t lock; @@ -60,19 +97,21 @@ struct pxa_i2c { u32 icrlog[32]; void __iomem *reg_base; + unsigned int reg_shift; unsigned long iobase; unsigned long iosize; int irq; - int use_pio; + unsigned int use_pio :1; + unsigned int fast_mode :1; }; -#define _IBMR(i2c) ((i2c)->reg_base + 0) -#define _IDBR(i2c) ((i2c)->reg_base + 8) -#define _ICR(i2c) ((i2c)->reg_base + 0x10) -#define _ISR(i2c) ((i2c)->reg_base + 0x18) -#define _ISAR(i2c) ((i2c)->reg_base + 0x20) +#define _IBMR(i2c) ((i2c)->reg_base + (0x0 << (i2c)->reg_shift)) +#define _IDBR(i2c) ((i2c)->reg_base + (0x4 << (i2c)->reg_shift)) +#define _ICR(i2c) ((i2c)->reg_base + (0x8 << (i2c)->reg_shift)) +#define _ISR(i2c) ((i2c)->reg_base + (0xc << (i2c)->reg_shift)) +#define _ISAR(i2c) ((i2c)->reg_base + (0x10 << (i2c)->reg_shift)) /* * I2C Slave mode address @@ -188,14 +227,14 @@ static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c) static void i2c_pxa_abort(struct pxa_i2c *i2c) { - unsigned long timeout = jiffies + HZ/4; + int i = 250; if (i2c_pxa_is_slavemode(i2c)) { dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__); return; } - while (time_before(jiffies, timeout) && (readl(_IBMR(i2c)) & 0x1) == 0) { + while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) { unsigned long icr = readl(_ICR(i2c)); icr &= ~ICR_START; @@ -205,7 +244,8 @@ static void i2c_pxa_abort(struct pxa_i2c *i2c) show_state(i2c); - msleep(1); + mdelay(1); + i --; } writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP), @@ -364,7 +404,7 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c) writel(i2c->slave_addr, _ISAR(i2c)); /* set control register values */ - writel(I2C_ICR_INIT, _ICR(i2c)); + writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c)); #ifdef CONFIG_I2C_PXA_SLAVE dev_info(&i2c->adap.dev, "Enabling slave mode\n"); @@ -907,12 +947,6 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num struct pxa_i2c *i2c = adap->algo_data; int ret, i; - /* If the I2C controller is disabled we need to reset it (probably due - to a suspend/resume destroying state). We do this here as we can then - avoid worrying about resuming the controller before its users. */ - if (!(readl(_ICR(i2c)) & ICR_IUE)) - i2c_pxa_reset(i2c); - for (i = adap->retries; i >= 0; i--) { ret = i2c_pxa_do_xfer(i2c, msgs, num); if (ret != I2C_RETRY) @@ -993,6 +1027,7 @@ static int i2c_pxa_probe(struct platform_device *dev) ret = -EIO; goto eremap; } + i2c->reg_shift = (cpu_is_pxa3xx() && (dev->id == 1)) ? 0 : 1; i2c->iobase = res->start; i2c->iosize = res_len(res); @@ -1013,6 +1048,7 @@ static int i2c_pxa_probe(struct platform_device *dev) if (plat) { i2c->adap.class = plat->class; i2c->use_pio = plat->use_pio; + i2c->fast_mode = plat->fast_mode; } if (i2c->use_pio) { @@ -1082,9 +1118,33 @@ static int __exit i2c_pxa_remove(struct platform_device *dev) return 0; } +#ifdef CONFIG_PM +static int i2c_pxa_suspend_late(struct platform_device *dev, pm_message_t state) +{ + struct pxa_i2c *i2c = platform_get_drvdata(dev); + clk_disable(i2c->clk); + return 0; +} + +static int i2c_pxa_resume_early(struct platform_device *dev) +{ + struct pxa_i2c *i2c = platform_get_drvdata(dev); + + clk_enable(i2c->clk); + i2c_pxa_reset(i2c); + + return 0; +} +#else +#define i2c_pxa_suspend_late NULL +#define i2c_pxa_resume_early NULL +#endif + static struct platform_driver i2c_pxa_driver = { .probe = i2c_pxa_probe, .remove = __exit_p(i2c_pxa_remove), + .suspend_late = i2c_pxa_suspend_late, + .resume_early = i2c_pxa_resume_early, .driver = { .name = "pxa2xx-i2c", .owner = THIS_MODULE, |