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Diffstat (limited to 'drivers/i2c/busses/i2c-omap.c')
-rw-r--r--drivers/i2c/busses/i2c-omap.c276
1 files changed, 216 insertions, 60 deletions
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index c7c237537f8..7674efb5537 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -37,6 +37,8 @@
#include <linux/platform_device.h>
#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
@@ -44,29 +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 */
@@ -156,6 +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;
@@ -166,9 +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
@@ -185,17 +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)
@@ -264,7 +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 {
@@ -329,7 +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);
@@ -356,7 +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
@@ -429,6 +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 |
@@ -538,8 +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;
@@ -622,6 +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
@@ -683,6 +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)
{
@@ -732,6 +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;
@@ -746,9 +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--;
@@ -786,9 +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--;
@@ -806,25 +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);
}
@@ -856,6 +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;
@@ -885,10 +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;
@@ -902,14 +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 */
@@ -921,15 +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);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-19 08:33:23 +0000