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authorMugunthan V N <mugunthanvnm@ti.com>2016-07-18 15:11:00 +0530
committerHeiko Schocher <hs@denx.de>2016-07-26 08:39:57 +0200
commitbe243e4113b6c3c302ee03050726358714f40ffe (patch)
tree3093919d0486d00940f21c3bbae96bf926bb7a41 /drivers/i2c
parenteff6b7731b03f3a387d83a2a5b7b78a3037e74b0 (diff)
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drivers: i2c: omap24xx_i2c: prepare driver for DM conversion
Prepare the driver for DM conversion. Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com> Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/omap24xx_i2c.c308
1 files changed, 175 insertions, 133 deletions
diff --git a/drivers/i2c/omap24xx_i2c.c b/drivers/i2c/omap24xx_i2c.c
index a7f3fb4..8dea5fa 100644
--- a/drivers/i2c/omap24xx_i2c.c
+++ b/drivers/i2c/omap24xx_i2c.c
@@ -53,10 +53,6 @@ DECLARE_GLOBAL_DATA_PTR;
/* Absolutely safe for status update at 100 kHz I2C: */
#define I2C_WAIT 200
-static int wait_for_bb(struct i2c_adapter *adap);
-static struct i2c *omap24_get_base(struct i2c_adapter *adap);
-static u16 wait_for_event(struct i2c_adapter *adap);
-static void flush_fifo(struct i2c_adapter *adap);
static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
{
unsigned int sampleclk, prescaler;
@@ -90,9 +86,96 @@ static int omap24_i2c_findpsc(u32 *pscl, u32 *psch, uint speed)
}
return -1;
}
-static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
+
+/*
+ * Wait for the bus to be free by checking the Bus Busy (BB)
+ * bit to become clear
+ */
+static int wait_for_bb(struct i2c *i2c_base, int waitdelay)
+{
+ int timeout = I2C_TIMEOUT;
+ u16 stat;
+
+ writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+ while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
+#else
+ /* Read RAW status */
+ while ((stat = readw(&i2c_base->irqstatus_raw) &
+ I2C_STAT_BB) && timeout--) {
+#endif
+ writew(stat, &i2c_base->stat);
+ udelay(waitdelay);
+ }
+
+ if (timeout <= 0) {
+ printf("Timed out in wait_for_bb: status=%04x\n",
+ stat);
+ return 1;
+ }
+ writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
+ return 0;
+}
+
+/*
+ * Wait for the I2C controller to complete current action
+ * and update status
+ */
+static u16 wait_for_event(struct i2c *i2c_base, int waitdelay)
+{
+ u16 status;
+ int timeout = I2C_TIMEOUT;
+
+ do {
+ udelay(waitdelay);
+#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
+ status = readw(&i2c_base->stat);
+#else
+ /* Read RAW status */
+ status = readw(&i2c_base->irqstatus_raw);
+#endif
+ } while (!(status &
+ (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
+ I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
+ I2C_STAT_AL)) && timeout--);
+
+ if (timeout <= 0) {
+ printf("Timed out in wait_for_event: status=%04x\n",
+ status);
+ /*
+ * If status is still 0 here, probably the bus pads have
+ * not been configured for I2C, and/or pull-ups are missing.
+ */
+ printf("Check if pads/pull-ups of bus are properly configured\n");
+ writew(0xFFFF, &i2c_base->stat);
+ status = 0;
+ }
+
+ return status;
+}
+
+static void flush_fifo(struct i2c *i2c_base)
+{
+ u16 stat;
+
+ /*
+ * note: if you try and read data when its not there or ready
+ * you get a bus error
+ */
+ while (1) {
+ stat = readw(&i2c_base->stat);
+ if (stat == I2C_STAT_RRDY) {
+ readb(&i2c_base->data);
+ writew(I2C_STAT_RRDY, &i2c_base->stat);
+ udelay(1000);
+ } else
+ break;
+ }
+}
+
+static int __omap24_i2c_setspeed(struct i2c *i2c_base, uint speed,
+ int *waitdelay)
{
- struct i2c *i2c_base = omap24_get_base(adap);
int psc, fsscll = 0, fssclh = 0;
int hsscll = 0, hssclh = 0;
u32 scll = 0, sclh = 0;
@@ -142,8 +225,7 @@ static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
}
}
- adap->speed = speed;
- adap->waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */
+ *waitdelay = (10000000 / speed) * 2; /* wait for 20 clkperiods */
writew(0, &i2c_base->con);
writew(psc, &i2c_base->psc);
writew(scll, &i2c_base->scll);
@@ -154,9 +236,8 @@ static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
return 0;
}
-static void omap24_i2c_deblock(struct i2c_adapter *adap)
+static void omap24_i2c_deblock(struct i2c *i2c_base)
{
- struct i2c *i2c_base = omap24_get_base(adap);
int i;
u16 systest;
u16 orgsystest;
@@ -200,9 +281,9 @@ static void omap24_i2c_deblock(struct i2c_adapter *adap)
writew(orgsystest, &i2c_base->systest);
}
-static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
+static void __omap24_i2c_init(struct i2c *i2c_base, int speed, int slaveadd,
+ int *waitdelay)
{
- struct i2c *i2c_base = omap24_get_base(adap);
int timeout = I2C_TIMEOUT;
int deblock = 1;
@@ -224,7 +305,7 @@ retry:
udelay(1000);
}
- if (0 != omap24_i2c_setspeed(adap, speed)) {
+ if (0 != __omap24_i2c_setspeed(i2c_base, speed, waitdelay)) {
printf("ERROR: failed to setup I2C bus-speed!\n");
return;
}
@@ -241,45 +322,24 @@ retry:
I2C_IE_NACK_IE | I2C_IE_AL_IE, &i2c_base->ie);
#endif
udelay(1000);
- flush_fifo(adap);
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
/* Handle possible failed I2C state */
- if (wait_for_bb(adap))
+ if (wait_for_bb(i2c_base, *waitdelay))
if (deblock == 1) {
- omap24_i2c_deblock(adap);
+ omap24_i2c_deblock(i2c_base);
deblock = 0;
goto retry;
}
}
-static void flush_fifo(struct i2c_adapter *adap)
-{
- struct i2c *i2c_base = omap24_get_base(adap);
- u16 stat;
-
- /*
- * note: if you try and read data when its not there or ready
- * you get a bus error
- */
- while (1) {
- stat = readw(&i2c_base->stat);
- if (stat == I2C_STAT_RRDY) {
- readb(&i2c_base->data);
- writew(I2C_STAT_RRDY, &i2c_base->stat);
- udelay(1000);
- } else
- break;
- }
-}
-
/*
* i2c_probe: Use write access. Allows to identify addresses that are
* write-only (like the config register of dual-port EEPROMs)
*/
-static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
+static int __omap24_i2c_probe(struct i2c *i2c_base, int waitdelay, uchar chip)
{
- struct i2c *i2c_base = omap24_get_base(adap);
u16 status;
int res = 1; /* default = fail */
@@ -287,7 +347,7 @@ static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
return res;
/* Wait until bus is free */
- if (wait_for_bb(adap))
+ if (wait_for_bb(i2c_base, waitdelay))
return res;
/* No data transfer, slave addr only */
@@ -296,7 +356,7 @@ static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
writew(I2C_CON_EN | I2C_CON_MST | I2C_CON_STT | I2C_CON_TRX |
I2C_CON_STP, &i2c_base->con);
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
if ((status & ~I2C_STAT_XRDY) == 0 || (status & I2C_STAT_AL)) {
/*
@@ -306,8 +366,8 @@ static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
* following 'if' section:
*/
if (status == I2C_STAT_XRDY)
- printf("i2c_probe: pads on bus %d probably not configured (status=0x%x)\n",
- adap->hwadapnr, status);
+ printf("i2c_probe: pads on bus probably not configured (status=0x%x)\n",
+ status);
goto pr_exit;
}
@@ -315,7 +375,7 @@ static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
/* Check for ACK (!NAK) */
if (!(status & I2C_STAT_NACK)) {
res = 0; /* Device found */
- udelay(adap->waitdelay);/* Required by AM335X in SPL */
+ udelay(waitdelay);/* Required by AM335X in SPL */
/* Abort transfer (force idle state) */
writew(I2C_CON_MST | I2C_CON_TRX, &i2c_base->con); /* Reset */
udelay(1000);
@@ -323,7 +383,7 @@ static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
I2C_CON_STP, &i2c_base->con); /* STP */
}
pr_exit:
- flush_fifo(adap);
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
return res;
}
@@ -341,10 +401,9 @@ pr_exit:
* or that do not need a register address at all (such as some clock
* distributors).
*/
-static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
- int alen, uchar *buffer, int len)
+static int __omap24_i2c_read(struct i2c *i2c_base, int waitdelay, uchar chip,
+ uint addr, int alen, uchar *buffer, int len)
{
- struct i2c *i2c_base = omap24_get_base(adap);
int i2c_error = 0;
u16 status;
@@ -389,7 +448,7 @@ static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
#endif
/* Wait until bus not busy */
- if (wait_for_bb(adap))
+ if (wait_for_bb(i2c_base, waitdelay))
return 1;
/* Zero, one or two bytes reg address (offset) */
@@ -410,12 +469,12 @@ static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
#endif
/* Send register offset */
while (1) {
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
/* Try to identify bus that is not padconf'd for I2C */
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
- printf("i2c_read (addr phase): pads on bus %d probably not configured (status=0x%x)\n",
- adap->hwadapnr, status);
+ printf("i2c_read (addr phase): pads on bus probably not configured (status=0x%x)\n",
+ status);
goto rd_exit;
}
if (status == 0 || (status & I2C_STAT_NACK)) {
@@ -450,7 +509,7 @@ static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
/* Receive data */
while (1) {
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
/*
* Try to identify bus that is not padconf'd for I2C. This
* state could be left over from previous transactions if
@@ -458,8 +517,8 @@ static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
*/
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
- printf("i2c_read (data phase): pads on bus %d probably not configured (status=0x%x)\n",
- adap->hwadapnr, status);
+ printf("i2c_read (data phase): pads on bus probably not configured (status=0x%x)\n",
+ status);
goto rd_exit;
}
if (status == 0 || (status & I2C_STAT_NACK)) {
@@ -477,16 +536,15 @@ static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
}
rd_exit:
- flush_fifo(adap);
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
return i2c_error;
}
/* i2c_write: Address (reg offset) may be 0, 1 or 2 bytes long. */
-static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
- int alen, uchar *buffer, int len)
+static int __omap24_i2c_write(struct i2c *i2c_base, int waitdelay, uchar chip,
+ uint addr, int alen, uchar *buffer, int len)
{
- struct i2c *i2c_base = omap24_get_base(adap);
int i;
u16 status;
int i2c_error = 0;
@@ -536,7 +594,7 @@ static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
#endif
/* Wait until bus not busy */
- if (wait_for_bb(adap))
+ if (wait_for_bb(i2c_base, waitdelay))
return 1;
/* Start address phase - will write regoffset + len bytes data */
@@ -549,12 +607,12 @@ static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
while (alen) {
/* Must write reg offset (one or two bytes) */
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
/* Try to identify bus that is not padconf'd for I2C */
if (status == I2C_STAT_XRDY) {
i2c_error = 2;
- printf("i2c_write: pads on bus %d probably not configured (status=0x%x)\n",
- adap->hwadapnr, status);
+ printf("i2c_write: pads on bus probably not configured (status=0x%x)\n",
+ status);
goto wr_exit;
}
if (status == 0 || (status & I2C_STAT_NACK)) {
@@ -576,7 +634,7 @@ static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
}
/* Address phase is over, now write data */
for (i = 0; i < len; i++) {
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
if (status == 0 || (status & I2C_STAT_NACK)) {
i2c_error = 1;
printf("i2c_write: error waiting for data ACK (status=0x%x)\n",
@@ -598,87 +656,21 @@ static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
* transferred on the bus.
*/
do {
- status = wait_for_event(adap);
+ status = wait_for_event(i2c_base, waitdelay);
} while (!(status & I2C_STAT_ARDY) && timeout--);
if (timeout <= 0)
printf("i2c_write: timed out writig last byte!\n");
wr_exit:
- flush_fifo(adap);
+ flush_fifo(i2c_base);
writew(0xFFFF, &i2c_base->stat);
return i2c_error;
}
/*
- * Wait for the bus to be free by checking the Bus Busy (BB)
- * bit to become clear
- */
-static int wait_for_bb(struct i2c_adapter *adap)
-{
- struct i2c *i2c_base = omap24_get_base(adap);
- int timeout = I2C_TIMEOUT;
- u16 stat;
-
- writew(0xFFFF, &i2c_base->stat); /* clear current interrupts...*/
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
- while ((stat = readw(&i2c_base->stat) & I2C_STAT_BB) && timeout--) {
-#else
- /* Read RAW status */
- while ((stat = readw(&i2c_base->irqstatus_raw) &
- I2C_STAT_BB) && timeout--) {
-#endif
- writew(stat, &i2c_base->stat);
- udelay(adap->waitdelay);
- }
-
- if (timeout <= 0) {
- printf("Timed out in wait_for_bb: status=%04x\n",
- stat);
- return 1;
- }
- writew(0xFFFF, &i2c_base->stat); /* clear delayed stuff*/
- return 0;
-}
-
-/*
- * Wait for the I2C controller to complete current action
- * and update status
+ * The legacy I2C functions. These need to get removed once
+ * all users of this driver are converted to DM.
*/
-static u16 wait_for_event(struct i2c_adapter *adap)
-{
- struct i2c *i2c_base = omap24_get_base(adap);
- u16 status;
- int timeout = I2C_TIMEOUT;
-
- do {
- udelay(adap->waitdelay);
-#if defined(CONFIG_OMAP243X) || defined(CONFIG_OMAP34XX)
- status = readw(&i2c_base->stat);
-#else
- /* Read RAW status */
- status = readw(&i2c_base->irqstatus_raw);
-#endif
- } while (!(status &
- (I2C_STAT_ROVR | I2C_STAT_XUDF | I2C_STAT_XRDY |
- I2C_STAT_RRDY | I2C_STAT_ARDY | I2C_STAT_NACK |
- I2C_STAT_AL)) && timeout--);
-
- if (timeout <= 0) {
- printf("Timed out in wait_for_event: status=%04x\n",
- status);
- /*
- * If status is still 0 here, probably the bus pads have
- * not been configured for I2C, and/or pull-ups are missing.
- */
- printf("Check if pads/pull-ups of bus %d are properly configured\n",
- adap->hwadapnr);
- writew(0xFFFF, &i2c_base->stat);
- status = 0;
- }
-
- return status;
-}
-
static struct i2c *omap24_get_base(struct i2c_adapter *adap)
{
switch (adap->hwadapnr) {
@@ -710,6 +702,56 @@ static struct i2c *omap24_get_base(struct i2c_adapter *adap)
return NULL;
}
+
+static int omap24_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
+ int alen, uchar *buffer, int len)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+
+ return __omap24_i2c_read(i2c_base, adap->waitdelay, chip, addr,
+ alen, buffer, len);
+}
+
+
+static int omap24_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
+ int alen, uchar *buffer, int len)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+
+ return __omap24_i2c_write(i2c_base, adap->waitdelay, chip, addr,
+ alen, buffer, len);
+}
+
+static uint omap24_i2c_setspeed(struct i2c_adapter *adap, uint speed)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+ int ret;
+
+ ret = __omap24_i2c_setspeed(i2c_base, speed, &adap->waitdelay);
+ if (ret) {
+ error("%s: set i2c speed failed\n", __func__);
+ return ret;
+ }
+
+ adap->speed = speed;
+
+ return 0;
+}
+
+static void omap24_i2c_init(struct i2c_adapter *adap, int speed, int slaveadd)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+
+ return __omap24_i2c_init(i2c_base, speed, slaveadd, &adap->waitdelay);
+}
+
+static int omap24_i2c_probe(struct i2c_adapter *adap, uchar chip)
+{
+ struct i2c *i2c_base = omap24_get_base(adap);
+
+ return __omap24_i2c_probe(i2c_base, adap->waitdelay, chip);
+}
+
#if !defined(CONFIG_SYS_OMAP24_I2C_SPEED1)
#define CONFIG_SYS_OMAP24_I2C_SPEED1 CONFIG_SYS_OMAP24_I2C_SPEED
#endif