diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
-rw-r--r-- | drivers/i2c/busses/i2c-omap.c | 275 |
1 files changed, 215 insertions, 60 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 6bd0f19cd45..7674efb5537 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -38,6 +38,7 @@ #include <linux/clk.h> #include <linux/io.h> #include <linux/slab.h> +#include <linux/i2c-omap.h> /* I2C controller revisions */ #define OMAP_I2C_REV_2 0x20 @@ -45,29 +46,37 @@ /* I2C controller revisions present on specific hardware */ #define OMAP_I2C_REV_ON_2430 0x36 #define OMAP_I2C_REV_ON_3430 0x3C +#define OMAP_I2C_REV_ON_4430 0x40 /* timeout waiting for the controller to respond */ #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000)) -#define OMAP_I2C_REV_REG 0x00 -#define OMAP_I2C_IE_REG 0x01 -#define OMAP_I2C_STAT_REG 0x02 -#define OMAP_I2C_IV_REG 0x03 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */ -#define OMAP_I2C_WE_REG 0x03 -#define OMAP_I2C_SYSS_REG 0x04 -#define OMAP_I2C_BUF_REG 0x05 -#define OMAP_I2C_CNT_REG 0x06 -#define OMAP_I2C_DATA_REG 0x07 -#define OMAP_I2C_SYSC_REG 0x08 -#define OMAP_I2C_CON_REG 0x09 -#define OMAP_I2C_OA_REG 0x0a -#define OMAP_I2C_SA_REG 0x0b -#define OMAP_I2C_PSC_REG 0x0c -#define OMAP_I2C_SCLL_REG 0x0d -#define OMAP_I2C_SCLH_REG 0x0e -#define OMAP_I2C_SYSTEST_REG 0x0f -#define OMAP_I2C_BUFSTAT_REG 0x10 +enum { + OMAP_I2C_REV_REG = 0, + OMAP_I2C_IE_REG, + OMAP_I2C_STAT_REG, + OMAP_I2C_IV_REG, + OMAP_I2C_WE_REG, + OMAP_I2C_SYSS_REG, + OMAP_I2C_BUF_REG, + OMAP_I2C_CNT_REG, + OMAP_I2C_DATA_REG, + OMAP_I2C_SYSC_REG, + OMAP_I2C_CON_REG, + OMAP_I2C_OA_REG, + OMAP_I2C_SA_REG, + OMAP_I2C_PSC_REG, + OMAP_I2C_SCLL_REG, + OMAP_I2C_SCLH_REG, + OMAP_I2C_SYSTEST_REG, + OMAP_I2C_BUFSTAT_REG, + OMAP_I2C_REVNB_LO, + OMAP_I2C_REVNB_HI, + OMAP_I2C_IRQSTATUS_RAW, + OMAP_I2C_IRQENABLE_SET, + OMAP_I2C_IRQENABLE_CLR, +}; /* I2C Interrupt Enable Register (OMAP_I2C_IE): */ #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */ @@ -157,6 +166,9 @@ #define SYSC_IDLEMODE_SMART 0x2 #define SYSC_CLOCKACTIVITY_FCLK 0x2 +/* Errata definitions */ +#define I2C_OMAP_ERRATA_I207 (1 << 0) +#define I2C_OMAP3_1P153 (1 << 1) struct omap_i2c_dev { struct device *dev; @@ -167,9 +179,13 @@ struct omap_i2c_dev { struct clk *fclk; /* Functional clock */ struct completion cmd_complete; struct resource *ioarea; + u32 latency; /* maximum mpu wkup latency */ + void (*set_mpu_wkup_lat)(struct device *dev, + long latency); u32 speed; /* Speed of bus in Khz */ u16 cmd_err; u8 *buf; + u8 *regs; size_t buf_len; struct i2c_adapter adapter; u8 fifo_size; /* use as flag and value @@ -186,17 +202,67 @@ struct omap_i2c_dev { u16 bufstate; u16 syscstate; u16 westate; + u16 errata; +}; + +const static u8 reg_map[] = { + [OMAP_I2C_REV_REG] = 0x00, + [OMAP_I2C_IE_REG] = 0x01, + [OMAP_I2C_STAT_REG] = 0x02, + [OMAP_I2C_IV_REG] = 0x03, + [OMAP_I2C_WE_REG] = 0x03, + [OMAP_I2C_SYSS_REG] = 0x04, + [OMAP_I2C_BUF_REG] = 0x05, + [OMAP_I2C_CNT_REG] = 0x06, + [OMAP_I2C_DATA_REG] = 0x07, + [OMAP_I2C_SYSC_REG] = 0x08, + [OMAP_I2C_CON_REG] = 0x09, + [OMAP_I2C_OA_REG] = 0x0a, + [OMAP_I2C_SA_REG] = 0x0b, + [OMAP_I2C_PSC_REG] = 0x0c, + [OMAP_I2C_SCLL_REG] = 0x0d, + [OMAP_I2C_SCLH_REG] = 0x0e, + [OMAP_I2C_SYSTEST_REG] = 0x0f, + [OMAP_I2C_BUFSTAT_REG] = 0x10, +}; + +const static u8 omap4_reg_map[] = { + [OMAP_I2C_REV_REG] = 0x04, + [OMAP_I2C_IE_REG] = 0x2c, + [OMAP_I2C_STAT_REG] = 0x28, + [OMAP_I2C_IV_REG] = 0x34, + [OMAP_I2C_WE_REG] = 0x34, + [OMAP_I2C_SYSS_REG] = 0x90, + [OMAP_I2C_BUF_REG] = 0x94, + [OMAP_I2C_CNT_REG] = 0x98, + [OMAP_I2C_DATA_REG] = 0x9c, + [OMAP_I2C_SYSC_REG] = 0x20, + [OMAP_I2C_CON_REG] = 0xa4, + [OMAP_I2C_OA_REG] = 0xa8, + [OMAP_I2C_SA_REG] = 0xac, + [OMAP_I2C_PSC_REG] = 0xb0, + [OMAP_I2C_SCLL_REG] = 0xb4, + [OMAP_I2C_SCLH_REG] = 0xb8, + [OMAP_I2C_SYSTEST_REG] = 0xbC, + [OMAP_I2C_BUFSTAT_REG] = 0xc0, + [OMAP_I2C_REVNB_LO] = 0x00, + [OMAP_I2C_REVNB_HI] = 0x04, + [OMAP_I2C_IRQSTATUS_RAW] = 0x24, + [OMAP_I2C_IRQENABLE_SET] = 0x2c, + [OMAP_I2C_IRQENABLE_CLR] = 0x30, }; static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev, int reg, u16 val) { - __raw_writew(val, i2c_dev->base + (reg << i2c_dev->reg_shift)); + __raw_writew(val, i2c_dev->base + + (i2c_dev->regs[reg] << i2c_dev->reg_shift)); } static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg) { - return __raw_readw(i2c_dev->base + (reg << i2c_dev->reg_shift)); + return __raw_readw(i2c_dev->base + + (i2c_dev->regs[reg] << i2c_dev->reg_shift)); } static int __init omap_i2c_get_clocks(struct omap_i2c_dev *dev) @@ -265,7 +331,11 @@ static void omap_i2c_idle(struct omap_i2c_dev *dev) WARN_ON(dev->idle); dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG); - omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0); + if (dev->rev >= OMAP_I2C_REV_ON_4430) + omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 1); + else + omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0); + if (dev->rev < OMAP_I2C_REV_2) { iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */ } else { @@ -330,7 +400,9 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) * REVISIT: Some wkup sources might not be needed. */ dev->westate = OMAP_I2C_WE_ALL; - omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate); + if (dev->rev < OMAP_I2C_REV_ON_4430) + omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, + dev->westate); } } omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0); @@ -357,7 +429,7 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) psc = fclk_rate / 12000000; } - if (cpu_is_omap2430() || cpu_is_omap34xx()) { + if (!(cpu_class_is_omap1() || cpu_is_omap2420())) { /* * HSI2C controller internal clk rate should be 19.2 Mhz for @@ -430,6 +502,11 @@ static int omap_i2c_init(struct omap_i2c_dev *dev) /* Take the I2C module out of reset: */ omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN); + dev->errata = 0; + + if (cpu_is_omap2430() || cpu_is_omap34xx()) + dev->errata |= I2C_OMAP_ERRATA_I207; + /* Enable interrupts */ dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY | OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK | @@ -539,8 +616,12 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, * REVISIT: We should abort the transfer on signals, but the bus goes * into arbitration and we're currently unable to recover from it. */ + if (dev->set_mpu_wkup_lat != NULL) + dev->set_mpu_wkup_lat(dev->dev, dev->latency); r = wait_for_completion_timeout(&dev->cmd_complete, OMAP_I2C_TIMEOUT); + if (dev->set_mpu_wkup_lat != NULL) + dev->set_mpu_wkup_lat(dev->dev, -1); dev->buf_len = 0; if (r < 0) return r; @@ -623,6 +704,34 @@ omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat) omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat); } +static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat) +{ + /* + * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8) + * Not applicable for OMAP4. + * Under certain rare conditions, RDR could be set again + * when the bus is busy, then ignore the interrupt and + * clear the interrupt. + */ + if (stat & OMAP_I2C_STAT_RDR) { + /* Step 1: If RDR is set, clear it */ + omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR); + + /* Step 2: */ + if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) + & OMAP_I2C_STAT_BB)) { + + /* Step 3: */ + if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) + & OMAP_I2C_STAT_RDR) { + omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR); + dev_dbg(dev->dev, "RDR when bus is busy.\n"); + } + + } + } +} + /* rev1 devices are apparently only on some 15xx */ #ifdef CONFIG_ARCH_OMAP15XX @@ -684,6 +793,35 @@ omap_i2c_rev1_isr(int this_irq, void *dev_id) #define omap_i2c_rev1_isr NULL #endif +/* + * OMAP3430 Errata 1.153: When an XRDY/XDR is hit, wait for XUDF before writing + * data to DATA_REG. Otherwise some data bytes can be lost while transferring + * them from the memory to the I2C interface. + */ +static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err) +{ + unsigned long timeout = 10000; + + while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) { + if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { + omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY | + OMAP_I2C_STAT_XDR)); + *err |= OMAP_I2C_STAT_XUDF; + return -ETIMEDOUT; + } + + cpu_relax(); + *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); + } + + if (!timeout) { + dev_err(dev->dev, "timeout waiting on XUDF bit\n"); + return 0; + } + + return 0; +} + static irqreturn_t omap_i2c_isr(int this_irq, void *dev_id) { @@ -733,6 +871,10 @@ complete: } if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) { u8 num_bytes = 1; + + if (dev->errata & I2C_OMAP_ERRATA_I207) + i2c_omap_errata_i207(dev, stat); + if (dev->fifo_size) { if (stat & OMAP_I2C_STAT_RRDY) num_bytes = dev->fifo_size; @@ -747,9 +889,12 @@ complete: if (dev->buf_len) { *dev->buf++ = w; dev->buf_len--; - /* Data reg from 2430 is 8 bit wide */ - if (!cpu_is_omap2430() && - !cpu_is_omap34xx()) { + /* + * Data reg in 2430, omap3 and + * omap4 is 8 bit wide + */ + if (cpu_class_is_omap1() || + cpu_is_omap2420()) { if (dev->buf_len) { *dev->buf++ = w >> 8; dev->buf_len--; @@ -787,9 +932,12 @@ complete: if (dev->buf_len) { w = *dev->buf++; dev->buf_len--; - /* Data reg from 2430 is 8 bit wide */ - if (!cpu_is_omap2430() && - !cpu_is_omap34xx()) { + /* + * Data reg in 2430, omap3 and + * omap4 is 8 bit wide + */ + if (cpu_class_is_omap1() || + cpu_is_omap2420()) { if (dev->buf_len) { w |= *dev->buf++ << 8; dev->buf_len--; @@ -807,25 +955,9 @@ complete: break; } - /* - * OMAP3430 Errata 1.153: When an XRDY/XDR - * is hit, wait for XUDF before writing data - * to DATA_REG. Otherwise some data bytes can - * be lost while transferring them from the - * memory to the I2C interface. - */ - - if (dev->rev <= OMAP_I2C_REV_ON_3430) { - while (!(stat & OMAP_I2C_STAT_XUDF)) { - if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { - omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); - err |= OMAP_I2C_STAT_XUDF; - goto complete; - } - cpu_relax(); - stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); - } - } + if ((dev->errata & I2C_OMAP3_1P153) && + errata_omap3_1p153(dev, &stat, &err)) + goto complete; omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); } @@ -857,6 +989,7 @@ omap_i2c_probe(struct platform_device *pdev) struct omap_i2c_dev *dev; struct i2c_adapter *adap; struct resource *mem, *irq, *ioarea; + struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data; irq_handler_t isr; int r; u32 speed = 0; @@ -886,10 +1019,13 @@ omap_i2c_probe(struct platform_device *pdev) goto err_release_region; } - if (pdev->dev.platform_data != NULL) - speed = *(u32 *)pdev->dev.platform_data; - else - speed = 100; /* Defualt speed */ + if (pdata != NULL) { + speed = pdata->clkrate; + dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat; + } else { + speed = 100; /* Default speed */ + dev->set_mpu_wkup_lat = NULL; + } dev->speed = speed; dev->idle = 1; @@ -903,14 +1039,29 @@ omap_i2c_probe(struct platform_device *pdev) platform_set_drvdata(pdev, dev); + if (cpu_is_omap7xx()) + dev->reg_shift = 1; + else if (cpu_is_omap44xx()) + dev->reg_shift = 0; + else + dev->reg_shift = 2; + if ((r = omap_i2c_get_clocks(dev)) != 0) goto err_iounmap; + if (cpu_is_omap44xx()) + dev->regs = (u8 *) omap4_reg_map; + else + dev->regs = (u8 *) reg_map; + omap_i2c_unidle(dev); dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff; - if (cpu_is_omap2430() || cpu_is_omap34xx()) { + if (dev->rev <= OMAP_I2C_REV_ON_3430) + dev->errata |= I2C_OMAP3_1P153; + + if (!(cpu_class_is_omap1() || cpu_is_omap2420())) { u16 s; /* Set up the fifo size - Get total size */ @@ -922,15 +1073,19 @@ omap_i2c_probe(struct platform_device *pdev) * size. This is to ensure that we can handle the status on int * call back latencies. */ - dev->fifo_size = (dev->fifo_size / 2); - dev->b_hw = 1; /* Enable hardware fixes */ + if (dev->rev >= OMAP_I2C_REV_ON_4430) { + dev->fifo_size = 0; + dev->b_hw = 0; /* Disable hardware fixes */ + } else { + dev->fifo_size = (dev->fifo_size / 2); + dev->b_hw = 1; /* Enable hardware fixes */ + } + /* calculate wakeup latency constraint for MPU */ + if (dev->set_mpu_wkup_lat != NULL) + dev->latency = (1000000 * dev->fifo_size) / + (1000 * speed / 8); } - if (cpu_is_omap7xx()) - dev->reg_shift = 1; - else - dev->reg_shift = 2; - /* reset ASAP, clearing any IRQs */ omap_i2c_init(dev); |